Compression Woes 2: The Revenge

[Tofuball]

I promise this isn't the same as the previous thread called "Compression Woes" :P

OK, I have an 82 GS850. I just rebuilt the engine (worn rings on cyl 3 (had a nice rusty ring inside, yum), had 25K on it but sat for a while before I drove it, I never checked valve clearance before)

I was getting ready to set the valve clearances for the very first time . . . so I've got the lobe pointing at 9:00 and I cannot get even one of my feeler gauges to fit on any of them! (Well, except the #1 cylinder intake valve, where I can fit only the .01 feeler in!)

Just for fun I tried turning the lobe to pointing straight up and it still wont fit any of my feelers in.

Now I was super careful and used a calibrated torque wrench when I put the engine together, what could be causing this?

I'm hoping it is something simple and stupid that I did so I can be up and running again soon!

Thank you in advance for your time!

[robertbarr]

... then they're too tight.

Start pulling shims and noting their thicknesses. Stay organized. Odds are, you can swap a few and at least get in the ballpark. If not, you'll know roughly how much thinner you need to go to get to the point where you have SOME clearance to measure.

It's not that tough. It's harder to explain than it is to do.

[Nessism]

Now I was super careful and used a calibrated torque wrench when I put the engine together, what could be causing this?

I'm hoping it is something simple and stupid that I did so I can be up and running again soon!

Time for a valve adjustment. Basic maintenance that should be performed every 3000 miles or so. If you don't know how, do a search and find BassCliff's excellent pictorial.

[Tofuball]

... then they're too tight.

Start pulling shims and noting their thicknesses. Stay organized. Odds are, you can swap a few and at least get in the ballpark. If not, you'll know roughly how much thinner you need to go to get to the point where you have SOME clearance to measure.

It's not that tough. It's harder to explain than it is to do.

Yeah, thats what I was sitting down to do when I found this out I thought it odd though that all of them would be too tight after this amount of time, as things usually loosen up with age. So, I was wondering if there was something else I did wrong that made them this tight.

All of them are the same thickness except for one on the #3 cyl, intake side.

I'm guessing then I'll have to buy a wad of them that have to be way too small and then buy a whole other set.

Thanks for your reply!

Time for a valve adjustment. Basic maintenance that should be performed every 3000 miles or so. If you don't know how, do a search and find BassCliff's excellent pictorial.

Thanks!

[Nessism]

Yeah, thats what I was sitting down to do when I found this out I thought it odd though that all of them would be too tight after this amount of time, as things usually loosen up with age. So, I was wondering if there was something else I did wrong that made them this tight.

All of them are the same thickness except for one on the #3 cyl, intake side.

I'm guessing then I'll have to buy a wad of them that have to be way too small and then buy a whole other set.

Thanks for your reply!

Thanks!

Two valve GS engines have a lot of surface area on the cam and tappet surface thus they do not wear very much. The valve tends to sink into the head thus the clearance decreases with time. Because the valves require shims to adjust many people never do the job and the engines die with burned valves.

[Tofuball]

Two valve GS engines have a lot of surface area on the cam and tappet surface thus they do not wear very much. The valve tends to sink into the head thus the clearance decreases with time. Because the valves require shims to adjust many people never do the job and the engines die with burned valves.

Ahh, that makes sense, makes me glad I checked to make sure the valves were sealing before reassembly.

I'm off to buy some shims, thanks for your help!