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Cmyers41

New plugs, Techron, now...right cylinder not firing

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Cmyers41

Put a fresh set of 3923 Plugs in my 99RT and put a bottle of techron in a quarter tank let it warm up, started down the road...now the throttle side cylinder isn't firing. Check by pulling it as it was running.... New to BMWs so I'm not sure where to begin.

 

I did have some low RPM surging prior to the lack of my throttle side cylinder not firing.

 

Thanks!

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dirtrider
32 minutes ago, Cmyers41 said:

Put a fresh set of 3923 Plugs in my 99RT and put a bottle of techron in a quarter tank let it warm up, started down the road...now the throttle side cylinder isn't firing. Check by pulling it as it was running.... New to BMWs so I'm not sure where to begin.

 

I did have some low RPM surging prior to the lack of my throttle side cylinder not firing.

 

Thanks!

Evening Cmyers41

 

Usual cause is the R/H throttle cable out of it's adjuster at the R/H side throttle body (sitting on top of the adjuster) not down in it.

 

If that isn't the problem then is it possible that you damaged the spark plug wire on that side when you removed it from the spark plug. You can measure the entire secondary side resistance by using an ohmmeter & measuring from one spark plug wire (spark plug wire end) to the other side  spark plug wire end. If you show an open then you have a damaged plug wire, or  one plug wire  is pulled loose from the ignition coil.

 

Also, slight chance that putting full bottle of techron in a quarter tank of fuel might have fouled the the dead cylinder spark plug (worth a look anyhow).

 

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Cmyers41
42 minutes ago, dirtrider said:

Evening Cmyers41

 

Usual cause is the R/H throttle cable out of it's adjuster at the R/H side throttle body (sitting on top of the adjuster) not down in it.

 

If that isn't the problem then is it possible that you damaged the spark plug wire on that side when you removed it from the spark plug. You can measure the entire secondary side resistance by using an ohmmeter & measuring from one spark plug wire (spark plug wire end) to the other side  spark plug wire end. If you show an open then you have a damaged plug wire, or  one plug wire  is pulled loose from the ignition coil.

 

Also, slight chance that putting full bottle of techron in a quarter tank of fuel might have fouled the the dead cylinder spark plug (worth a look anyhow).

 

Thanks for the reply!

 

Haven't dug into it yet, but is throttle cable adjustment pretty involved?

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dirtrider
35 minutes ago, Cmyers41 said:

Thanks for the reply!

 

Haven't dug into it yet, but is throttle cable adjustment pretty involved?

Evening Cmyers41

 

No adjustment needed, just make sure that the cable is seated in the throttle body adjuster correctly.

 

If you didn't have the R/H side plastics off the motorcycle  then bumping that cable out of position is much lower (just something that should be checked). 

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Cmyers41
23 minutes ago, dirtrider said:

Evening Cmyers41

 

No adjustment needed, just make sure that the cable is seated in the throttle body adjuster correctly.

 

If you didn't have the R/H side plastics off the motorcycle  then bumping that cable out of position is much lower (just something that should be checked). 

I did get the R/H plastics off but then realized the ignition and, I'm assuming the throttle body adjuster, are underneath the fuel tank. I'll need some more time to dig into it. My children are not allowing for more time tonight 😂.

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dirtrider
11 hours ago, Cmyers41 said:

I did get the R/H plastics off but then realized the ignition and, I'm assuming the throttle body adjuster, are underneath the fuel tank. I'll need some more time to dig into it. My children are not allowing for more time tonight 😂.

Morning  Cmyers41

 

(If),  you have a cable seating problem then it is usually right at the throttle body where the throttle cable attaches.  

 

ruIeIRl.jpg

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Cmyers41
8 hours ago, dirtrider said:

Morning  Cmyers41

 

(If),  you have a cable seating problem then it is usually right at the throttle body where the throttle cable attaches.  

 

ruIeIRl.jpg

So this is what I'm looking at. I started it up and twisted the throttle, RPMs went up. However, I pushed the throttle on the right side cylinder only and got nothing. Not sure if that means anything though.

 

20201013_144531.thumb.jpg.02695d493051fdd6d3cd621f60d341d5.jpg

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dirtrider
23 minutes ago, Cmyers41 said:

So this is what I'm looking at. I started it up and twisted the throttle, RPMs went up. However, I pushed the throttle on the right side cylinder only and got nothing. Not sure if that means anything though.

 

 

Afternoon Cmyers41

 

Cable looks good at adjuster seat so that isn't the problem.

 

You can NOT just open the R/H throttle body alone as it doesn't have a TPS (Throttle Position Sensor) so ALL it gets is air when you open it, with no fuel added.

 

You can open the L/H side alone, or both together, but NOT the R/H side alone.   

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Cmyers41
1 hour ago, dirtrider said:

Afternoon Cmyers41

 

Cable looks good at adjuster seat so that isn't the problem.

 

You can NOT just open the R/H throttle body alone as it doesn't have a TPS (Throttle Position Sensor) so ALL it gets is air when you open it, with no fuel added.

 

You can open the L/H side alone, or both together, but NOT the R/H side alone.   

Ah, ok makes sense. Note sure if it means anything or not, but when I open the R/H side it sounds like the engine is under a load/ bogs down a bit.

 

Next is to check the coils...which looks like I have to take the tank off for.

 

I've also noticed my R/H plug wire seem a little loose compared to my L/H. Hopefully it's as simple as the plug pulled out of the coil.

 

Was able to pull the coil...small crack on the bottom of it. Switched the wires around to see if that changes anything. 

 

It didn't. Pulled the R/H plug as it was running...no change.

 

Bad coil???

 

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dirtrider
1 hour ago, Cmyers41 said:

Ah, ok makes sense. Note sure if it means anything or not, but when I open the R/H side it sounds like the engine is under a load/ bogs down a bit.

 

Next is to check the coils...which looks like I have to take the tank off for.

 

I've also noticed my R/H plug wire seem a little loose compared to my L/H. Hopefully it's as simple as the plug pulled out of the coil.

 

Was able to pull the coil...small crack on the bottom of it. Switched the wires around to see if that changes anything. 

 

It didn't. Pulled the R/H plug as it was running...no change.

 

Bad coil???

 

Afternoon Cmyers41

 

That crack in the coil sure isn't a good sign but possibly not your problem as the same coil sparks both side spark plugs from the same coil at the same time.

 

Take one of your old spark plugs (or any good spark plug from about anything) then open the gap (best you can to about 3/16" electrode gap. Then stick that (special) spark plug in the R/H side plug wire, now lay the plug on the top of the cylinder head, the start the engine.  

 

You need to see a decent snappy bluish colored spark across that 3/16" plug electrode gap  (do you?)

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Cmyers41
23 minutes ago, dirtrider said:

Afternoon Cmyers41

 

That crack in the coil sure isn't a good sign but possibly not your problem as the same coil sparks both side spark plugs from the same coil at the same time.

 

Take one of your old spark plugs (or any good spark plug from about anything) then open the gap (best you can to about 3/16" electrode gap. Then stick that (special) spark plug in the R/H side plug wire, now lay the plug on the top of the cylinder head, the start the engine.  

 

You need to see a decent snappy bluish colored spark across that 3/16" plug electrode gap  (do you?)

I saw the tiniest orange spark when I was able to burry it in the head bolt. Other than that...nothing.

 

 

20201013_170730.jpg

20201013_170719.jpg

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dirtrider
14 minutes ago, Cmyers41 said:

I saw the tiniest orange spark when I was able to burry it in the head bolt. Other than that...nothing.

 

Afternoon Cmyers41

 

OK, that is not the cylinder head that is the valve cover. The valve cover is pretty well rubber isolated from the cylinder head.

 

Re-run your test using the CYLINDER HEAD itself not the valve cover. Or use an exhaust bolt.

 

Do you have an ohm meter?    

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Cmyers41

I'm an idiot...

 

Tried an exhaust bolt...nada.

 

20201013_172902.thumb.jpg.0f43de5c95c4a5606cb8376a2cc29020.jpg

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dirtrider
27 minutes ago, Cmyers41 said:

I'm an idiot...

 

Tried an exhaust bolt...nada.

 

Afternoon Cmyers41

Afternoon Cmyers41

 

OK, that sort of points to either the spark plug wire being pulled out of the coil (it seems that you already addressed that), or you have a damaged plug wire.

 

Again, do you have an ohmmeter?  

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Cmyers41

Pardon my ignorance...

 

I believe I can. I have this multimeter, and judging by the symbol on the bottom left I can...just not sure what the proper settings are.

 

 

20201013_181703.jpg

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dirtrider
36 minutes ago, Cmyers41 said:

Pardon my ignorance...

 

I believe I can. I have this multimeter, and judging by the symbol on the bottom left I can...just not sure what the proper settings are.

 

 

 

Afternoon Cmyers41

 

Put your meter on the 200 ohm scale (ohm sign looks like an upside down horseshoe on your meter)

 

Then measure from the metal on the coil end of your spark plug wire to metal on the spark plug end.

 

If your wire is good you should measure somewhere around  5-6 ohms. (doesn't have to be exact just in that neighborhood) 

 

As a double check also measure the L/H side wire as it seems to be working OK. 

 

I won't be back to this thread until tomorrow so do what you can. 

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Cmyers41

Good evening.

 

Not sure if I did correctly, but on the R/H I was getting between 90 and 132. The bike turned over and it bounced back and forth while it was running.

 

On the R/H I was getting a steady 120 while the bike was cranking.

 

Again, not sure if I went about it correctly. The probes on my multimeter were a little short to get into the coil end of the spark plug wire, but I was touching metal.

 

Thanks!

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Hosstage

Ohms are just measuring the resistance of the wire, from one end to the other, not the power that is being put through it. Disconnect each from the coil and spark plug, measure the ohms of the wire itself, not running.

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Cmyers41
3 minutes ago, Hosstage said:

Hope this helps.

IMG_20201013_201829415.jpg

That's fantastically clear for me... Pictures like that take it down to my 5th grade level

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Cmyers41
15 minutes ago, Hosstage said:

Hope this helps.

IMG_20201013_201829415.jpg

So here's what I got. Please note I switched my meter to the 20k ohms setting to get these numbers. Not that I know what I'm doing, just started switch around the settings to see what I could get.  When I had it set to the 200 ohms setting the meter showed "1." And nothing else.

20201013_213638.jpg

20201013_213711.jpg

20201013_213720.jpg

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Cmyers41

This is what the bottom of my coil looks like...my very uneducated guess is this may be the culprit, just judging by it's looks. Also, is there a special way to pull that connector out of the coil? It seems nearly welded in there, and won't budge.

 

 

Thanks!!

 

 

20201013_215202.jpg

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Hosstage

I'll let DR take it from here.

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dirtrider
9 hours ago, Cmyers41 said:

So here's what I got. Please note I switched my meter to the 20k ohms setting to get these numbers. Not that I know what I'm doing, just started switch around the settings to see what I could get.  When I had it set to the 200 ohms setting the meter showed "1." And nothing else.

20201013_213638.jpg

 

 

Morning  Cmyers41 

 

You did good, I had 20 different things going on at the same time last night so forgot to add the (K) after the numbers that I gave you (I fixed it for future readers to use as reference). 

 

Your spark plug wire resistance numbers are in the ballpark so your problem probably lies in another area. (resistance numbers can prove a bad plug wire but not necessarily prove a good plug wire)

 

That coil looks bad & should be replaced but still might not be the problem as one side IS sparking. 

 

You probably should measure the coil's resistance next__ See below for coil resistance numbers. (note: there were 2 different coil designs used  so if you get  13K ohm for the secondary and 0.5 ohm for the primary you have the other coil) 

 

Just keep in mind that resistance measurements alone will not prove a coil good (it could show good windings resistance but still be arcing internally). Resistance measurements can show a coil BAD but not necessarily prove it a good coil. 

 

 

5vl9YN2.jpg

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Cmyers41
6 hours ago, dirtrider said:

Morning  Cmyers41 

 

You did good, I had 20 different things going on at the same time last night so forgot to add the (K) after the numbers that I gave you (I fixed it for future readers to use as reference). 

 

Your spark plug wire resistance numbers are in the ballpark so your problem probably lies in another area. (resistance numbers can prove a bad plug wire but not necessarily prove a good plug wire)

 

That coil looks bad & should be replaced but still might not be the problem as one side IS sparking. 

 

You probably should measure the coil's resistance next__ See below for coil resistance numbers. (note: there were 2 different coil designs used  so if you get  13K ohm for the secondary and 0.5 ohm for the primary you have the other coil) 

 

Just keep in mind that resistance measurements alone will not prove a coil good (it could show good windings resistance but still be arcing internally). Resistance measurements can show a coil BAD but not necessarily prove it a good coil. 

 

 

5vl9YN2.jpg

 

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Cmyers41

No worries, I greatly appreciate the advice you've give thus far!

 

I'll probably test the coil tomorrow when I'm not at work.

 

It's a little mind boggling to me that one cylinder can be firing, seemingly, just fine and the other not. Which makes me thing it's a fuel problem.  I checked the air box, and besides an old dirty filter, there is nothing blocking air. 

 

Trial and error I suppose. I'll report back with the readings on the coil.

 

Thanks again!

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dirtrider
1 minute ago, Cmyers41 said:

No worries, I greatly appreciate the advice you've give thus far!

 

I'll probably test the coil tomorrow when I'm not at work.

 

It's a little mind boggling to me that one cylinder can be firing, seemingly, just fine and the other not. Which makes me thing it's a fuel problem.  I checked the air box, and besides an old dirty filter, there is nothing blocking air. 

 

Trial and error I suppose. I'll report back with the readings on the coil.

 

Thanks again!

Cmyers41 

 

A couple of quick tests to run__

 

First, try one of your old spark plugs on the bad cyl side (see if that makes a difference). Possibly your new spark plug is defective.

 

Try swapping the plug wires at the coil, if that helps the bad side then probably a coil issue. If it doesn't help then problem probably lies in another area. If problem moves to the other side then again probably a bad coil. 

 

  

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Mrclubike
8 hours ago, Cmyers41 said:

 

 

It's a little mind boggling to me that one cylinder can be firing, seemingly, just fine and the other not. 

 

 

A bad coil can short to ground internally and cause only one side to go dead

 

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dirtrider
10 hours ago, Mrclubike said:

A bad coil can short to ground internally and cause only one side to go dead

 

Morning  Mrclubike

 

Yes, "some" coils can short to ground internally but the coil on  Cmyers41/s 1100 isn't one of those as his coil is a plastic encased coil that sparks as a lost-spark system (so no coil case connection to ground).  The BMW 1100 coil (shown above in Cmyers41,s post)  has an isolated secondary that actually sparks as a continuous loop from one end of the coil's secondary winding through both spark plugs (one side sparks center electrode positive & the other side sparks center electrode negative), then returns to the opposite end of the secondary coil winding.   

 

It could arc internally between the primary & secondary, it could arc internally between the secondary coil windings (usual cause of decreased spark output), it could "short" between adjacent secondary windings (but that would also decrease the available spark to both sides). The only place that plastic cased coil could SHORT to ground is EXTERNALLY on the primary (low) side wire going to the Motronic. But that would kill ALL spark not just one side.

 

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Cmyers41
4 hours ago, dirtrider said:

Morning  Mrclubike

 

Yes, "some" coils can short to ground internally but the coil on  Cmyers41/s 1100 isn't one of those as his coil is a plastic encased coil that sparks as a lost-spark system (so no coil case connection to ground).  The BMW 1100 coil (shown above in Cmyers41,s post)  has an isolated secondary that actually sparks as a continuous loop from one end of the coil's secondary winding through both spark plugs (one side sparks center electrode to side electrode & one side sparks side electrode to center electrode), then returns to the opposite end of the secondary coil winding.   

 

It could arc internally between the primary & secondary, it could arc internally between the secondary coil windings (usual cause of decreased spark output), it could "short" between adjacent secondary windings (but that would also decrease the available spark to both sides). The only place that plastic cased coil could SHORT to ground is EXTERNALLY on the primary (low) side wire going to the Motronic. But that would kill ALL spark not just one side.

 

Dang, a lot going on here. 

 

Haven't had the chance to test the coil yet. Keep getting called into work.

 

Hypothetically, if it is the coil, which appears to need replaced anyway, what should I buy looking for in a used one?

 

I looked through eBay and found several but prices vary wildly. Some also appear to be labeled for GS or RS machines. Are there different models and years that share the same coils that I can look for, that are interchangeable?

 

I'm very used to old Honda's and know what is interchangeable. For example my 1980 CB750F currently has coils and plugs from a 1997 CBR600, but these BMWs are a while new monster to me and my knowledge is limited. 

 

Thanks!!

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dirtrider
10 minutes ago, Cmyers41 said:

Dang, a lot going on here. 

 

Haven't had the chance to test the coil yet. Keep getting called into work.

 

Hypothetically, if it is the coil, which appears to need replaced anyway, what should I buy looking for in a used one?

 

I looked through eBay and found several but prices vary wildly. Some also appear to be labeled for GS or RS machines. Are there different models and years that share the same coils that I can look for, that are interchangeable?

 

I'm very used to old Honda's and know what is interchangeable. For example my 1980 CB750F currently has coils and plugs from a 1997 CBR600, but these BMWs are a while new monster to me and my knowledge is limited. 

 

Thanks!!

Morning  Cmyers41 

 

There are basically 2 coils for your 1100, the early one is  not the one to get so you want the later (all plastic case one) 

 

Look for a black plastic coil with a reddish colored belly (see picture below).  

 

 

late 1100 coil.jpg

1100 coil (bottom view).jpg

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Michaelr11
33 minutes ago, Cmyers41 said:

looked through eBay and found several but prices vary wildly. Some also appear to be labeled for GS or RS machines. Are there different models and years that share the same coils that I can look for, that are interchangeable?


Once you start working on the bike, you should bookmark the Max BMW parts fiche. There is a section for the fiche, which is very helpful. It has extra photos and sometimes install instructions. When you have a part number for your bike, copy that into the Search box and it will give you all of the bikes that the part also fits.

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Cmyers41

Still haven't had the opportunity to check the coil but I just had a thought...

 

Not sure if it's going to be relevant / helpful in this diagnosis...

 

Soon after I put the Techron in, I noticed some pops and backfiring when I started the bike up. I dismissed it as it was the Techron doing its job, or something to that effect. Then I went for a quick test ride down the road. Gave it some throttle and about a quarter mile down the road is when I lost the R/H cylinder...

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dirtrider
12 minutes ago, Cmyers41 said:

Still haven't had the opportunity to check the coil but I just had a thought...

 

Not sure if it's going to be relevant / helpful in this diagnosis...

 

Soon after I put the Techron in, I noticed some pops and backfiring when I started the bike up. I dismissed it as it was the Techron doing its job, or something to that effect. Then I went for a quick test ride down the road. Gave it some throttle and about a quarter mile down the road is when I lost the R/H cylinder...

Afternoon Cmyers41

 

It sort of sounds like you might have fouled the R/H spark plug with all that Techron. Have you tried one of your old spark plugs in that R/H side per my suggestion above? 

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Cmyers41
48 minutes ago, dirtrider said:

Afternoon Cmyers41

 

It sort of sounds like you might have fouled the R/H spark plug with all that Techron. Have you tried one of your old spark plugs in that R/H side per my suggestion above? 

I'm almost certain I did. I'll do it again though just to be sure. The old plugs were Bosch and the new ones were the 3923s, if that matters.

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dirtrider
2 hours ago, Cmyers41 said:

I'm almost certain I did. I'll do it again though just to be sure. The old plugs were Bosch and the new ones were the 3923s, if that matters.

Afternoon Cmyers41

 

Spark plug brand makes no difference as long as you get a KNOWN GOOD spark plug in that side.

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Cmyers41

Finally got a chance to test my coil...here's what I got... nevermind the poor pictures, I had my 5yo take the pictures for me.😂

 

Also...checked the R/H cylinder with both old plugs... no changes.

20201017_143917.jpg

20201017_143851.jpg

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dirtrider
2 hours ago, Cmyers41 said:

Finally got a chance to test my coil...here's what I got... nevermind the poor pictures, I had my 5yo take the pictures for me.😂

 

Also...checked the R/H cylinder with both old plugs... no changes.

20201017_143917.jpg

20201017_143851.jpg

Afternoon Cmyers41

 

Well, your coil tests good, doesn't mean it isn't arcing internally but it does test good (ohm wise) anyhow. So it doesn't show any internal coil winding shorting or opens. 

 

That R/H side spark was poor looking so we can't disregard that but we might have to move on  to something else as fixating on the spark might be overlooking something else. Was the other side plug wire on the spark  plug when you tested the R/H side for spark?? Opposite side plug wire needs to be connected to get full spark intensity.

 

So, first thing is move that large electrode spark plug to the L/H side then see what you get for a spark on that side?  (this will allow us to move on)

 

Do you have any way of doing a compression test (at some point that should be done).

 

You might also try swapping the fuel injectors side to side as test-- If the problem moves with the fuel injectors then that will give us something to work with.  

 

Then possibly do a fuel return flow test as at some point we will have to verify enough fuel pressure at enough fuel flow . 

 

Lastly (for now anyhow) get someone to slowly open & close the twist grip as you (carefully) put one hand on each side throttle body cam. Then see if you can verify that both side TB cams lift off their base idle stop screws & hit wide open throttle at the very same time. (at some point his needs to be verified, might as well be now) 

 

 

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Cmyers41
31 minutes ago, dirtrider said:

Afternoon Cmyers41

 

Well, your coil tests good, doesn't mean it isn't arcing internally but it does test good (ohm wise) anyhow. So it doesn't show any internal coil winding shorting or opens. 

 

That R/H side spark was poor looking so we can't disregard that but we might have to move on  to something else as fixating on the spark might be overlooking something else. Was the other side plug wire on the spark  plug when you tested the R/H side for spark?? Opposite side plug wire needs to be connected to get full spark intensity.

 

So, first thing is move that large electrode spark plug to the L/H side then see what you get for a spark on that side?  (this will allow us to move on)

 

Do you have any way of doing a compression test (at some point that should be done).

 

You might also try swapping the fuel injectors side to side as test-- If the problem moves with the fuel injectors then that will give us something to work with.  

 

Then possibly do a fuel return flow test as at some point we will have to verify enough fuel pressure at enough fuel flow . 

 

Lastly (for now anyhow) get someone to slowly open & close the twist grip as you (carefully) put one hand on each side throttle body cam. Then see if you can verify that both side TB cams lift off their base idle stop screws & hit wide open throttle at the very same time. (at some point his needs to be verified, might as well be now) 

 

 

I tested the L/H spark, it sparked but it wasn't that blueish color you spoke of...more orange, and not what I could call snappy.

 

I have no way to do a compression test.

 

As for the injectors...will I need to replace any seals after I swap them? Or can I just swap them, put them back on and plug and play?

 

No idea how to do a fuel return flow test, but more than willing to learn.

 

I'll get the wife to help me with the TB cams later on when she's not busy.

 

Thanks!!

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dirtrider
23 minutes ago, Cmyers41 said:

 

Afternoon Cmyers41

 

 

I tested the L/H spark, it sparked but it wasn't that blueish color you spoke of...more orange, and not what I could call snappy.-- OK, even with that less than great spark it does run on the other side so possibly your poor spark is just due to lower coil voltage while cranking. If one side runs on orange spark then the other side should do that also. (you do need a new coil but that might not be your current issue) 

 

I have no way to do a compression test.--Eventually you might have to find a way to do this. For now we will work around it.

 

As for the injectors...will I need to replace any seals after I swap them? Or can I just swap them, put them back on and plug and play?-- Usually not, unless your current "O" rings are in real bad shape. 

 

No idea how to do a fuel return flow test, but more than willing to learn.-- I will post a how-to later. 

 

I'll get the wife to help me with the TB cams later on when she's not busy.-- Pay close attention to both sides starting of solidly on their base idle screws. 

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jeffyjeff
9 hours ago, dirtrider said:

Afternoon Cmyers41

 

Well, your coil tests good, doesn't mean it isn't arcing internally but it does test good (ohm wise) anyhow. So it doesn't show any internal coil winding shorting or opens. 

 

 

Respectfully, are you sure about that?  I had a vintage Amprobe meter back in the day that displayed 1. to indicate OL.  Coincidentally, it was also a manual ranging meter, like the Sperry pictured.  Allow me to suggest that the primary side of the coil could be high resistance.  Maybe try taking the reading again with a different meter?  It's not on the appropriate scale if the specification is 1 ohm resistance.  That reading looks wrong to me.

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dirtrider
5 hours ago, jeffyjeff said:

 

Respectfully, are you sure about that?  I had a vintage Amprobe meter back in the day that displayed 1. to indicate OL.  Coincidentally, it was also a manual ranging meter, like the Sperry pictured.  Allow me to suggest that the primary side of the coil could be high resistance.  Maybe try taking the reading again with a different meter?  It's not on the appropriate scale if the specification is 1 ohm resistance.  That reading looks wrong to me.

Morning   jeffyjeff

 

Good catch, now that I take a look closer it looks odd to me also. 

 

The engine wouldn't run if the primary was open (or extremely high resistance)  so I saw the 1. & that is spec. 

 

Cmyers41-- put your meter on the 200 ohm scale (not 200K scale) then re-test it. 

 

Also, show us a picture of meter reading with meter on 200 ohm scale & probes not touching anything, then show us a picture with probe metal tips held together, then show us a picture of a re-measure of the coils primary. 

 

 

 

  

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Cmyers41
2 hours ago, dirtrider said:

Morning   jeffyjeff

 

Good catch, now that I take a look closer it looks odd to me also. 

 

The engine wouldn't run if the primary was open (or extremely high resistance)  so I saw the 1. & that is spec. 

 

Cmyers41-- put your meter on the 200 ohm scale (not 200K scale) then re-test it. 

 

Also, show us a picture of meter reading with meter on 200 ohm scale & probes not touching anything, then show us a picture with probe metal tips held together, then show us a picture of a re-measure of the coils primary. 

 

 

Good morning.

 

Here's what I got on the remeasure...

 

Please note I did switch the probes around on each connection just to be thorough. Not sure if it matters or not but I figured it would hurt.

 

Thanks!

2 hours ago, dirtrider said:

 

  

 

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dirtrider
19 minutes ago, Cmyers41 said:

Good morning.

 

Here's what I got on the remeasure...

 

Please note I did switch the probes around on each connection just to be thorough. Not sure if it matters or not but I figured it would hurt.

 

Thanks!

 

Morning Cmyers41

 

OK, that shows that jeffyjeff was correct in that your original measurement of 1 .  indicated OL not 1 ohm.

 

Still, that  1.5 ohm is in the ball park (probably closer to 1.3 as it looks like you have .2 ohm resistance in your meter leads, would like to see it closer to 1.0  but I have measured perfectly good late coils at 1.3 ohms or even slightly higher. 

 

You might try cleaning your meter lead metal tips as those can get a slight oxidation & add a bit of resistance. (you  would like to see 0.00 when you touch the leads together)

 

No need to re-measure as your above pictures show no open or shorted primary. (engine won't run with an open primary, & a shorted primary would show lower resistance).  

 

Still doesn't prove that you have no internal coil arcing though.   

 

You can maybe do one more test while you have your meter out. Do a quick  voltage measurement between the green wire going to the coil & the battery negative post while cranking engine.  (be nice to know what the coil's supply voltage is during engine cranking)

 

 

 

 

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Cmyers41
1 hour ago, dirtrider said:

Morning Cmyers41

 

OK, that shows that jeffyjeff was correct in that your original measurement of 1 .  indicated OL not 1 ohm.

 

Still, that  1.5 ohm is in the ball park (probably closer to 1.3 as it looks like you have .2 ohm resistance in your meter leads, would like to see it closer to 1.0  but I have measured perfectly good late coils at 1.3 ohms or even slightly higher. 

 

You might try cleaning your meter lead metal tips as those can get a slight oxidation & add a bit of resistance. (you  would like to see 0.00 when you touch the leads together)

 

No need to re-measure as your above pictures show no open or shorted primary. (engine won't run with an open primary, & a shorted primary would show lower resistance).  

 

Still doesn't prove that you have no internal coil arcing though.   

 

You can maybe do one more test while you have your meter out. Do a quick  voltage measurement between the green wire going to the coil & the battery negative post while cranking engine.  (be nice to know what the coil's supply voltage is during engine cranking)

 

 

 

 

The first is while it was cranking.

 

The second is just with the ignition in the on position.

 

Unsure of the battery...it came with the bike and is really small for the battery tray. I put it on a tender as soon as I got the bike last week. A quick Google search showed it's a pretty cheap ($35) battery from Amazon. Not sure if that is playing a role in my problem or not.

 

Thanks!!!

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dirtrider
1 minute ago, Cmyers41 said:

The first is while it was cranking.

 

The second is just with the ignition in the on position.

 

Unsure of the battery...it came with the bike and is really small for the battery tray. I put it on a tender as soon as I got the bike last week. A quick Google search showed it's a pretty cheap ($35) battery from Amazon. Not sure if that is playing a role in my problem or not.

 

Thanks!!!

 

 

Morning Cmyers41

 

OK, thanks, that 9.24 is pretty low for coil primary voltage during engine cranking. Even the 12.09 is low but that is system voltage so isn't true battery voltage. (that could easily explain the orange wimpy spark that you saw in the cranking spark test)

 

That isn't your problem as the low coil voltage only effects engine starting not runability once engine is started.

 

That circles it right back to finding the reason that the R/H cylinder isn't firing. 

 

Have you done the check to see if both side throttle cams start out firmly ON the base idle screws, then open together, then hit the wide open stops at the same time?  (we kind of need to know that before we move on)

 

   

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Cmyers41
1 hour ago, dirtrider said:

Morning Cmyers41

 

OK, thanks, that 9.24 is pretty low for coil primary voltage during engine cranking. Even the 12.09 is low but that is system voltage so isn't true battery voltage. (that could easily explain the orange wimpy spark that you saw in the cranking spark test)

 

That isn't your problem as the low coil voltage only effects engine starting not runability once engine is started.

 

That circles it right back to finding the reason that the R/H cylinder isn't firing. 

 

Have you done the check to see if both side throttle cams start out firmly ON the base idle screws, then open together, then hit the wide open stops at the same time?  (we kind of need to know that before we move on)

 

   

I have a nearly brand new battery on my CB, would it be beneficial to see if swapping the batteries makes any difference?

 

Throttle cams seat firmly and hit the stops at the same time.

 

Working on swapping the injectors now.

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dirtrider
27 minutes ago, Cmyers41 said:

I have a nearly brand new battery on my CB, would it be beneficial to see if swapping the batteries makes any difference?

 

Afternoon Cmyers41

 

I'm not sure that battery swap would tell you much as your dead cylinder happens with the engine running so at that time you are pretty well running on the alternator output not the battery. 

 

As long as it starts OK then your battery isn't the issue with a dead cylinder. 

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Cmyers41
1 hour ago, dirtrider said:

Afternoon Cmyers41

 

I'm not sure that battery swap would tell you much as your dead cylinder happens with the engine running so at that time you are pretty well running on the alternator output not the battery. 

 

As long as it starts OK then your battery isn't the issue with a dead cylinder. 

Swapped the injectors...now it won't start.

 

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dirtrider
2 minutes ago, Cmyers41 said:

Swapped the injectors...now it won't start.

 

Afternoon Cmyers41

 

You don't have the side stand down do you? 

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