Piston ring positions - How critical???

[hampshirehog]

Some guy at Suzuki, Clymer or Haynes layed out the diagram, and it just so happens thats where he pointed them in it.

But don't forget, according to Haynes, the bogeyman will get you if you dare to touch those screws on your carbs

 

[juicydangershow]

Well if I decide to tear it down again, I would have the opportunity to get all the great pics I should have gotten (and posted) along the way in the first place!

The head gasket was rubberized, but I am not sure if it was rubberized metal. It had 4 crush rings for the cylinders, 4 copper crush rings around the corner studs and 4 rubberized washers that sit on top of the copper holes. It was a Vesrah brand. The metal rings around the cylinders where the same size on both sides of the gasket, the copper rings on the corners were wider on one side. I placed the wider side UP and put the little rubberized washers on top of those copper holes. Vesrah should label the gasket TOP side and give some indication about the washer placement and orientation (they were rubberized metal, with more rubber on one side). I placed them rubberized side up. Those washers are a pain to make sure they stay placed when seating the head. I often wonder if they ended up moving on me at the last moment.

If I have to get another head gasket, I would definitely look for a brand that had everything built into the gasket.

 

[TheCafeKid]

Well if I decide to tear it down again, I would have the opportunity to get all the great pics I should have gotten (and posted) along the way in the first place!

The head gasket was rubberized, but I am not sure if it was rubberized metal. It had 4 crush rings for the cylinders, 4 copper crush rings around the corner studs and 4 rubberized washers that sit on top of the copper holes. It was a Vesrah brand. The metal rings around the cylinders where the same size on both sides of the gasket, the copper rings on the corners were wider on one side. I placed the wider side UP and put the little rubberized washers on top of those copper holes. Vesrah should label the gasket TOP side and give some indication about the washer placement and orientation (they were rubberized metal, with more rubber on one side). I placed them rubberized side up. Those washers are a pain to make sure they stay placed when seating the head. I often wonder if they ended up moving on me at the last moment.

If I have to get another head gasket, I would definitely look for a brand that had everything built into the gasket.

Actually i think that this gasket is per OEM design. My 8v motor gaskets are all the same, or similar, to yours. they are Vesrah as well. However the Vesrah headgasket for Mike's 82 1100E that Steve and I have been working on is one peice, with no rubber or copper anythings. I think THAT is part of the 16v design. However, I DO agree with you on them marking top and bottom, since we're talking about specifics on things, the manual CLEARLY notes the gasket is usually marked TOP. None of the ones i have seen have been marked so. But, ive never had a leak from one of them yet either

 

[Guest]

i had the same gasket set

i had the same gasket set

Those washers are a pain to make sure they stay placed when seating the head. I often wonder if they ended up moving on me at the last moment.

yeah, quite a pita

 

[heathen]

i just rebuilt my 750 topend. the rings don't care where they are as long as there not lined up. also had to take mine back apart after running it for about an hour (oring moved in groove causing a oil leak) rebolted every thing but had to torque the head bolts 5 pounds over to seal so as not to have an oil leak. bike runs great so don't worry about where you positioned the rings. this is the first bike i have done but have built many drag race motors and as long as the rings are spaced apart it don't matter. as far as the rubber washers that go on the 4 corners. my original ones (36,000 miles) had droped down the holes and were sitting between the cylinder and the case. no orange rubber left on them. at first i thought that was where they went until i checked them and they fit in the head gasket.

 

[Steve]

IF they do move the likely possibility of the gap landing IN the exhaust port is, at the very least, possible. Now, add to that the exhaust temps on an "open" end of the ring (where there is less material to dissipate the heat) and "is there a chance of melting the end of a ring"?

Just how is it supposed to land in the exhaust port? The exhaust port is downstream of the exhaust valve, and methinks that if you have the ends of your rings landing in the exhaust port, you have some things that are considerably more important to worry about.

For those that did not catch on to the original post, the talk about keeping the rings out of the ports was concerning 2-stroke engines.
Our 4-stroke engines do not have ports in the cylinders.

 

[rustybronco]

where are the oil control ring gaps?
they should be spaced ABOUT 180 degrees from where you placed the 1st and 2nd rings with the gaps (spacer, top, bottom) of the oil ring staggered ABOUT 45 degrees or more.

if the oil control ring gaps are ABOUT 180 degrees from the placement of your top and 2nd rings.
the DAYUM thing will be just fine!!!!!!!!!!!!!!!!!!!

IF you are loosing sleep, take it apart.

 

[flyingace]

You know what, it's easy to say 'I'd take it all apart again', but if it isn't necessary, that's just plain foolish. There's nothing that's going to harm your bike. Run it and see what happens. And don't waste your $ on another head gasket!

Let me tell you a story about my 'top end' rebuild. I had a spare engine, so I took out the pistons. I cross-honed the cylinders and bought a $25 set of rings on Ebay. I had a set of feeler gaugues and took all eight pistons and mixed/matched them so they were the nearest to tolerance of the cylinders I could get. Then I put rings on pistons and pistons on rods and then the block over them. Then I used the old head gasket cause $85 was too much to replace a perfectly good 25 year old gasket. That was 8,000 miles ago and it still runs great.

Rebuild everything because they aren't exactly perfect!? Don't make me laugh.

 

[TheCafeKid]

You know what, it's easy to say 'I'd take it all apart again', but if it isn't necessary, that's just plain foolish. There's nothing that's going to harm your bike. Run it and see what happens. And don't waste your $ on another head gasket!

Let me tell you a story about my 'top end' rebuild. I had a spare engine, so I took out the pistons. I cross-honed the cylinders and bought a $25 set of rings on Ebay. I took a set of feeler gaugues and took all eight pistons and mixed/matched them so they were the nearest to tolerance of the cylinders I could get. Then I put pistons on the rods and then the block over them. Then I used the old head gasket cause $85 was too much to replace a perfectly good 25 year old gasket. That was 8,000 miles ago and it still runs great.

Rebuild everything because they aren't exactly perfect!? Don't make me laugh.

I have to agree. If its not passing oil thru the seals or rings, ride it. I am one that sweats over odd ball noises i hear, but the more and more i get used to working on these things, the less i worry about it. Its going to break something at some point. I dont sweat the top end anymore, because now i can repair it. I plan on crackin a spare motor i have open to teach myself how to rebuild the bottom end on these too. Thats the only part of the bikes I worry about now. If something in the top end blows, oh well, I will fix it. But if its something in the top end that can damage the bottom end, I start worrying...lol

 

[lecroy]

Ah, I loved working on those old scavanged port motors as a kid.... Times were simpler...

I pay close attention to the bore, piston clearance and ring gaps. I also keep close tabs on the deck height. My eyes are getting pretty bad now and so I tripple check that the rings are right side up.

I think I am pretty anal about motor assembly, except I do not use the correct tools when it comes to the rings. I still put them on by hand. A big no-no in anyone's book. Worse, I do not use a ring compressor to put the block on. I do it all by hand and have paid the price many a time when using copper base gaskets... Or as I like to call them, the slice-o-matic. Doing this all by hand, I eyeball the rings but they move as I compress them one by one and slide them in. Ryan showed me his home made PVC pipe compressors. I swore I would try this on my last project, but still did it by hand. This would help keep things in place and make the job much simpler.

I did a little search and read this article. I agree with it for the most part...
http://aircooled.net/gnrlsite/resource/articles/pcrops.htm

I think Ray works for a piston company. He could maybe shine some real data on this.

 

[80GS750]

i just got my 1000 back on the road, new rings installed....

mine are spaced correctly but not at the perfect interval the manual says..

everyone else is correct here in saying that as long as the gaps dont line up you will be fine

i have over 500 miles on mine now and the rings have seated nicely and it runs great!!!

 

[juicydangershow]

As a note:

The rings on this are not new. They are the old rings and only pulled the cylinders to prevent a base gasket leak after taking the head off. New rings, honing and everything else was not really an option at this time (money, time, etc. limits me on how far I can feasibly go with "rebuilding" this).

I have decided that I am not going to go back in at this time. Everyone's advice was helpful and appreciated... and I can see both schools of thought. One is to do it perfect and exactly as outlined by the shop manual, and the other is "get out and ride the damn thing!" I have to go with the latter for now. I'll post updates after it gets running, although I don't own a compression gauge tester, so I won't have hard numbers to report.

To answer a previous question about the oil rings:

The oil ring gaps seemed to be pretty much 180 degrees apart from on the top and bottom of all the oil rings and did not seem to move easily at all in relation to one another, so I didn't mess with them. I did not pay too close attention to their relation to the TOP and 2nd ring when hand pushing the pistons into the cylinders, but the oil ring gaps are so tiny uncompressed it probably wont matter so much anyhow.

 

[TheCafeKid]

As a note:

The rings on this are not new. They are the old rings and only pulled the cylinders to prevent a base gasket leak after taking the head off. New rings, honing and everything else was not really an option at this time (money, time, etc. limits me on how far I can feasibly go with "rebuilding" this).

I have decided that I am not going to go back in at this time. Everyone's advice was helpful and appreciated... and I can see both schools of thought. One is to do it perfect and exactly as outlined by the shop manual, and the other is "get out and ride the damn thing!" I have to go with the latter for now. I'll post updates after it gets running, although I don't own a compression gauge tester, so I won't have hard numbers to report.

To answer a previous question about the oil rings:

The oil ring gaps seemed to be pretty much 180 degrees apart from on the top and bottom of all the oil rings and did not seem to move easily at all in relation to one another, so I didn't mess with them. I did not pay too close attention to their relation to the TOP and 2nd ring when hand pushing the pistons into the cylinders, but the oil ring gaps are so tiny uncompressed it probably wont matter so much anyhow.

In my learning process, I did a top end on one of my 8v 750 motors that went in my cafe project. I didnt realize at the time how important honing was in the rebuild process, but i also didnt change the rings out either. They were in spec according to my caliper and the manual, so i left well enough alone. I did change the gasket cos the one that was on there had god knows how many miles on it, and was pretty much trashed when i removed the jugs. I also did the rings by hand, tho i have found later on when helping with Steves son's 850 motor, the hose clamp method works pretty damn well, and makes things MUCH easier than fighting with the jugs while trying to keep the rings compressed and lined up. I dunno if i got lucky in not honing the bores, or because i didnt change the rings, it didnt seem to change things at all. Put everything back together and she's running just fine (tho a little rich right now cos i havent quite got my needles dialed in) and NO leaks at all. She sounds great, much smoother than the motor that originally came in the bike, which will be getting completely SPLIT and rebuilt with 850 pistons and jugs soon.

 

[flyingace]

I'll also put in a plug for the hose clamp method. It allows you to lock the rings in place before you insert into the cylinder. You don't have to worry about them moving around during insertion. That alone makes it the best method (IMO), besides how easy it makes getting the pistons in.

 

[juicydangershow]

I disagree. I found the hose clamps awkward to use, not nearly a good finish on the inner surface to be clamping against the piston and ring sides and hard to take off after the piston is inserted. You have to unscrew the entire clamp. Most clamps have the screw built in so it wont fall out, but that is a possibility too. Don't want the screw falling in the crank as you remove the clamp in an awkward position. The rings also can get wedged into the cylinder tapered area as the pistons move up and the jugs start moving down. If you must use a clamping method... go out and get a real ring compressor with a nice inner surface and a better release method than screw clamps.

At least with my 850, I just oiled the pistons, rings, cylinders and finger pressed them up in there. The rings didn't seem to squirm around on me (although as noted I positioned them incorrectly before inserting them!). I thought that worked easier than anything else would have.

 

[GavinJuice]

At least with my 850, I just oiled the pistons, rings, cylinders and finger pressed them up in there. The rings didn't seem to squirm around on me (although as noted I positioned them incorrectly before inserting them!). I thought that worked easier than anything else would have.

Well now that you said THIS, you should pull it apart again. Install everything DRY, wipe the cylinder walls down with a clean terry cloth / WD40 and reinstall everything DRY. Also i would re-hone, but thats your choice. When you install everything all oiled up there is a very good chance the cylinder walls will glaze up.
I just thought i would mix everything up again ~Gavin

 

[TheCafeKid]

Well now that you said THIS, you should pull it apart again. Install everything DRY, wipe the cylinder walls down with a clean terry cloth / WD40 and reinstall everything DRY. Also i would re-hone, but thats your choice. When you install everything all oiled up there is a very good chance the cylinder walls will glaze up.
I just thought i would mix everything up again ~Gavin

Eh?? where did you get this info from? It says right in the manual to oil the rings when installing them. They wont glaze. Oil will burn right off in the first couple strokes.

 

[GavinJuice]

I'm sure the manual says during a break in to pus$y-foot it for at least a thousand miles too? Get some mojo brewing cauz your in for a read.... www.mototuneusa.com

 

[tkent02]

Eh?? where did you get this info from? It says right in the manual to oil the rings when installing them. They wont glaze. Oil will burn right off in the first couple strokes.

Every engine I've ever seen put together has been oiled.
Works fine, lasts a long time.
How silly.

Let's just fill the cylinders with sand to prevent glazing.
Or dead bugs. Grasshoppers and crickets.
Maybe use some marbles.
Yeah, that'll work.

 

[tkent02]

I'm sure the manual says during a break in to pus$y-foot it for at least a thousand miles too?
Nobody does that, get real.