Removing cylinder & head together

[RSL]

To remove both the cylnder and head from an oilhad bike, the exhaust header and throttle body must be removed, the timing chain sprocket removed and the chain zip-tied, the spark plug wire unplugged, and the 4 head stud nuts removed.

 

What else is needed to pull the cylinder and head from an oilhead bike? How long should this procedure take?

[RSL]

Surely somebody here has pulled a jug on an Oilhead.

 

How long should it take to remove the jug, and then put correctly put it back on?

[Joe Frickin' Friday]

IIRC, there are a few small bolts that hold the cylinder to the block, even after the large nuts are removed from the top of the long studs.

 

I'd guess an hour and a half to remove a head and cylinder. Installation will take a little longer, since you need to make sure everything's clean. There are small O-rings that seal the oil passages of the cylinder and head with the block (and with each other), but most of the mating surface between cylinder and block is sealed with RTV; you'll need to clean the old stuff off completely before applying new RTV, and that's gonna take a little elbow grease.

 

Curious, why are you pulling a head/cylinder?

[David McClain]

I've just completed that on my 95 RSL and agree that I could do it in an hour and a half provided the fuel tank, exhaust and TB's were removed.

Other than the four cylinder head nuts there are a couple of smaller bolts inside and outside the cam chain tunnel on both of the head and cylinder.

However I did not find the small O-rings that the parts fiche shows on the cylinder small dowel pins. Neither did I see a machined out groove on the engine block or cylinder that the O-ring would "sit in", so I elected not to install them. Of course as soon as I get it fired up (after the clutch spline lube) it may leak worse than the head gasket did before I tore it down

Good luck.....

[RSL]

Thanks Mitch and David.

 

I'm curious about removal of the cylinder & head together for the purpose of gaining efficient access to the head stud mounting holes in the aluminum engine case, to install a Time-Sert thread insert into a stipped stud hole. This on an R1100RSL like David's.

 

Studying the drawings and shop manuals, it seemed the job would be pretty straigtforward: Remove and set aside the fairing panel; Remove the 6 nuts and clamp of the headers, and set them aside; Unclamp the TB and slide it with its tube back into the snorkle housing; Unplug the sparkplug wire; Unscrew the 4 valve cover screws and set it aside; Remove the timing chain access cover, unbolt the sprocket, and zip-tie it to the chain; Slacken the timing chain tensioner; Remove the 4 head stud nuts and pull the head/cylinder assembly out far enough to access & remove the circlip holding the wrist pin on the piston; Withdraw the wrist pin and wrap the connecting rod with Duct tape, and; Pull the assembled head & cylinder (with piston still inside)off the 4 head studs, and set aside.

 

Now (per my suppositions) you have the exposed alu. engine case with 4 studs sticking out. Unscrew studs and repair with Time-Sert as necessary. Re-assemble in reverse order, torquing fasteners to factory specs.

 

What steps have I missed? What faults are there in this procedure? Would replacement of the head gasket be necessary?

 

The piston could be left on its rod, but compressing the rings to slip it back into the cylinder might be a troublesome.

 

Would the fuel tank need to be touched in this procedure?

 

Does ~90 minutes still seem a reasonable time for removal, and perhaps 120 minutes for re-assembly?

[ShovelStrokeEd]

That procedure will likely work but, you should probably go ahead and replace the head gasket anyway. You won't preserve its seal by removing the two together. It will be far easier to handle the assembly without the weight of the head in place. Compressing the piston rings during re-assembly is a non issue. There are commercially availabe ring compressors for this and the bottom of the cylinder has a taper to aid the process. I just use a couple of wide hose clamps with dings on them applied with a chisel to compress the rings. The dings keep the clamps from entering the tapered portion of the cylinder. 90 minutes if you have done this sort of stuff before, 2 hours or a little more if you have not.

[Joe Frickin' Friday]

That procedure will likely work but, you should probably go ahead and replace the head gasket anyway. You won't preserve its seal by removing the two together. It will be far easier to handle the assembly without the weight of the head in place. Compressing the piston rings during re-assembly is a non issue. There are commercially availabe ring compressors for this and the bottom of the cylinder has a taper to aid the process. I just use a couple of wide hose clamps with dings on them applied with a chisel to compress the rings. The dings keep the clamps from entering the tapered portion of the cylinder. 90 minutes if you have done this sort of stuff before, 2 hours or a little more if you have not.

 

Since the piston installs into the bottom end of the cylinder bore, you need a ring compressor that can be fastened/unfastened around the piston, rather than the kind that's a hollow tube you slip the piston into; you need to be able to unfasten/unwrap it after you start sliding the piston into the cylinder. Something like this. Worked great.

[TGarner]

I used to work in an engine rebuilding shop( many moons ago) and I used the ring compressor you show here. It worked great. Thanks for the link, I have been looking for one of these. I have the old school one at home that can not be disassembled.

[Reddog99]

I'm curious about removal of the cylinder & head together for the purpose of gaining efficient access to the head stud mounting holes in the aluminum engine case, to install a Time-Sert thread insert into a stipped stud hole. This on an R1100RSL like David's.

Be sure the insert you use has roughly the same threaded length as the stud threads. If you don't have enough engagement length, the insert could also strip out in the case.

 

Pat

[ShovelStrokeEd]

Hence the hose clamps. Once the rings have entered the bottom of the bore, you just unscrew them. All motorcycle motors with the exception of the flying bricks, the ST and the Goldwing use the same method. It can be fun on a 4 cylinder until you learn to lock up the motor using the transmission and rear brake.

[David McClain]

Of course try to remove the cylinder and head together but I don't think I could have accessed the two cylinder to engine block bolts unless the head was seperated first. The online parts fiche does show an 8mm bolt in the cylinders cam chain tunnel but doesn't show the 6mm bolt! Then again since my head gasket was leaking around tunnel I didn't try to remove them together.

 

There's two head gaskets listed, the parts guy at Hammersley said my bike needed the four piece one.

 

Upon disassembly it was easier to remove the cylinder then the piston, re-assembly was easier with the piston already in the cylinder.

 

During assembly I had to get the piston as low in the cylinder as possible without the oil ring popping out so there would be adequate clearance for the wrist pin to be inserted.

 

Not removing the fuel tank ......hmmmm why didn't I think of that ! Oh yeah....I'm pulling the tranny too! Good Luck

[RSL]

Mitch, wouldn't that piston ring compresser (like an oil filter wrench) be impossible to remove from the piston skirt (if piston still on its rod) once the piston is re-inserted into the bottom of the cylinder? Or, does the ring compresser open up so you can pull it out?

 

With a hose clamp you could compress the piston rings for insertion of piston into cylinder, then completely slacken and open up the hose clamp and pull it out like a piece of string.

 

And, David, I'm told the 3 layer head gasket supercedes the older 4 layer one that came on the early oilheads like ours. Does anybody know for sure? Hammersley charges a lot less for the 3 layer version.

 

Is there a bolt down in the chain tunnel that must be removed in order to take the cylinder off the aluminum engine case?

[Joe Frickin' Friday]

Mitch, wouldn't that piston ring compresser (like an oil filter wrench) be impossible to remove from the piston skirt (if piston still on its rod) once the piston is re-inserted into the bottom of the cylinder? Or, does the ring compresser open up so you can pull it out?

 

Exactly. It's a long strip that you wrap around the piston and fasten to itself to form a loop; once the rings are into the cylinder, you unfasten it from itself and unwrap it from the piston.

[David McClain]

 

 

And, David, I'm told the 3 layer head gasket supercedes the older 4 layer one that came on the early oilheads like ours. Does anybody know for sure? Hammersley charges a lot less for the 3 layer version.

 

Dummy me thought the four piece gasket included the valve cover gasket! I guess someone has to buy the old stock!

 

Is there a bolt down in the chain tunnel that must be removed in order to take the cylinder off the aluminum engine case?

 

Yes. I believe there's an 8mm bolt located high inside the chain tunnel and a 6mm bolt located lower and to the right.

Be careful not to lose the bolts and washers down the cam chain guide into the engine block.

And by the way, there's another bolt from the outside of the cylinder that holds the cam chain guide in place. The tensioner puts pressure on one half (upper or lower depending on which side you're working on) and this bolt holds the other half in a fixed position.

[dj_nj]

If I did this job at 90k, would there be any value in putting new rings in?

[David McClain]

That's the reason I took the pistons out on my RSL. It always used a lot of oil winding up in the airbox (blowby).

I did find one of the compression rings "flaking" or coming apart in layers. The cylinder looked great. Honed the cylinders, new rings and valve guide seals and re-lapped the valve seats. Only 45k miles on the bike but I wanted to reduce it's appetite for oil.

If you plan on keeping the bike another 90k miles and taking the cylinders off anyway......I would!

[RSL]

As simple and cheap as it would be to install new rings once the cylinder is off, I cannot imagine a good reason not to.

[Boffin]

That's the reason I took the pistons out on my RSL. It always used a lot of oil winding up in the airbox (blowby).

I did find one of the compression rings "flaking" or coming apart in layers. The cylinder looked great. Honed the cylinders, new rings and valve guide seals and re-lapped the valve seats. Only 45k miles on the bike but I wanted to reduce it's appetite for oil.

If you plan on keeping the bike another 90k miles and taking the cylinders off anyway......I would!

 

Oil in the airbox is usually a symptom of over-filling the oil. These bikes tend to like the oil at, or slightly below, the mid-point of the sight-glass and will pump out oil at a fair rate if it is a bit high. Remember the boxer engines pistons move in opposite directions and displace the full engine capacity of air under the pistons every stroke. There is a whole lot of air moving around down there.

 

Back on topic, whenever I strip a motor it gets new rings, valve springs and seals. On a BMW boxer I would add exhaust valves to the list because they have been kmown to burn out quite easilly.

 

Andy