Adjusting cam timing on GS550E

[scott]

Maybe the valves are hitting the piston. Might be best to remove the cams now, hold up the cam chain, and then carefully turn the crank where it needs to be then.

Ok - I removed the exhaust cam caps and pulled out the whole exhaust cam assembly. I put the cam slipper block back in. I tried rotating the camshaft and holding the chain up (note - the intake cam caps and assembly is still in) but it just seems to tighten the chain.

Can I turn the crankshaft counter-clockwise to loosen it?

Also, what the heck is in the cam caps? I noticed an odor as soon as the bolts broke loose but when I got them out and smelled them (bad idea), it was rancid - I actually had to get a drink of water.

[MisterCinders]

Yeah, the engine is hard to turn when the chain bunches up, so lifting the cam chain to lightly pull out the slack will allow you to line up the timing mark.

[Nessism]

Just pull both cams out. You can then rotate the engine as long as you hold up the cam chain.

Pull cams
Rotate engine to align 1-4 T
Install exhaust cam
Install intake cam
Install tensioner

[tom203]

"Also, what the heck is in the cam caps? I noticed an odor as soon as the bolts broke loose but when I got them out and smelled them (bad idea), it was rancid - I actually had to get a drink of water. "

Probably, a water-based coolant used during machining operations- trapped in the bottom of those holes ,I bet it smells real good after 31 years . Bon appetit!

[hampshirehog]

If you pull the cams to turn the engine over make sure that you don't let the cam chain drop down in to the tunnel (fiddly to get it back out) plus keep it tight in your hand to stop it bunching up at the bottom when you turn the engine.

[2BRacing]

Just my 2 cents worth on the "to use or not to use a vice grip" issue:

When my son bought a Suzuki 400 16 valve last year, we went through all the maintenance items. On this motor, the valve cover retaining bolts turn into small "towers" on the cam caps. As the thread in one of these "towers" had stripped, we removed that cap and obtained a replacement cap from the local bike breaker.

While tightening the cap in criss-cross pattern, it cracked at one end just before being fully tight. This was caused by the cam being lifted a little by the force of the valve springs, despite the other caps on that cam being tight. I had not ensured that the lobes on that part of the cam were not pressing down on the valve. If I had used a vice grip to hold the cam down (or if I had used my head to first check that the lobes were not down on the valves), there would not have been a problem!

[rollingroland]

The exhaust cam is most likely one tooth off, and the intake cam is three off since there are 23 pins between the 2 and 3 marks, and there should be 20.

I am thinking, if you correct the exhaust cam position, would'nt that change the situation for the intake cam,the number of pins between 2 and 3 would not be 23 anymore.

[scott]

Thanks for all the tips. I took both cams out and was able to get the chain moving (it must have bundled up somewhere). I managed to keep it from falling into the engine - so far at least.

Here is my latest attempt at setting the exhaust cam. I clamped it down with vice grips because it looks different than when it's sitting "up" with the lobe resting on the valve shim. I thought it looked to be pointing a little low after clamping it down but in this pic, it doesn't look too bad. Am I ready to install the cam caps or is another attempt required?



Should I take another pic? Maybe this has an odd angle to it.

Regarding the clamping: I wasn't able to fit the vice grips to clamp the intake cam down. That seems less important for setting the timing but could still cause an issue with stripping bolts.

[Nessism]

That exhaust cam looks good. Just double check the crank 1-4 T mark and as long as it's aligned, slam on those cam caps.

[scott]

I have both cams installed and capped. The cam chain tensioner is not installed yet (haven't even received the shipping confirmation for the seals/o-rings so I plan to install it as is and address the seals later).

Here is what it looks like with the exhaust cam capped - still looks reasonable to me:


And here is with the intake cam added. It's 20 pins but the chain looks too loose. I didn't clamp the intake cam down (no room to fit vice grips) so it may have shifted when I was bolting down the caps. Should I take off the intake and try again?

[Nessism]

The 2 to 3 phasing looks good, as does the -1 mark on the exhaust cam. As long as the crank is still on 1-4 T you are good to bolt on the tensioner. Don't forget to check the valve clearances before you put the valve cover back on.

[hampshirehog]

I count 20 pins so it looks good. The chain will be loose as you haven't got the tensioner on there yet. That's what it does - tensions the chain!

[scott]

I installed the tensioner - it seemed to pull the Ex cam up a bit. Hopefully not enough to be an issue. After rotating the crankshaft several times to 1-4 T:

Don't forget to check the valve clearances before you put the valve cover back on.

Since I just did that a month ago, I never would have thought to do this. I did find some odd things though. Is the best way to do this to find the size where you can't fit the feeler at all and then say it's one size lower? My intake valve clearances are higher than before using this method. I'm not saying it changed - I think previously I was going up in feeler gauge size until I felt some drag but I think that may be a less precise way to do it. For example, on one of my intake valves I could put a .08 + .06 gauges in (with a decent amount of drag). A .08 + .07 would not go through at all.

[tom203]

I installed the tensioner - it seemed to pull the Ex cam up a bit. Hopefully not enough to be an issue. After rotating the crankshaft several times to 1-4 T:



Since I just did that a month ago, I never would have thought to do this. I did find some odd things though. Is the best way to do this to find the size where you can't fit the feeler at all and then say it's one size lower? My intake valve clearances are higher than before using this method. I'm not saying it changed - I think previously I was going up in feeler gauge size until I felt some drag but I think that may be a less precise way to do it. For example, on one of my intake valves I could put a .08 + .06 gauges in (with a decent amount of drag). A .08 + .07 would not go through at all.

Fantastic! I bet you even used a torque wrench on those cam cap bolts. Personally, I like a little extra valve clearance, but at 8k, this motor hasn't done much and , you'll be doing it again soon to satisfy your curiosity.Play with that tensioner, till you grasp how it works inside the motor when unlocked.

[Suzuki_Don]

I installed the tensioner - it seemed to pull the Ex cam up a bit. Hopefully not enough to be an issue. After rotating the crankshaft several times to 1-4 T:



Since I just did that a month ago, I never would have thought to do this. I did find some odd things though. Is the best way to do this to find the size where you can't fit the feeler at all and then say it's one size lower? My intake valve clearances are higher than before using this method. I'm not saying it changed - I think previously I was going up in feeler gauge size until I felt some drag but I think that may be a less precise way to do it. For example, on one of my intake valves I could put a .08 + .06 gauges in (with a decent amount of drag). A .08 + .07 would not go through at all.

Scott do I understand correctly that you are placing two feeler gauges, a .08 & .06mm together and sliding them between the lobe base circle and the shim to do your measurements?

The valve clearance for your motor should be .03 to .08, if you are inserting both feeler blades under the cam then that totals .14mm which is way too wide for valve clearance.

I repeat the clearance is .03 to .08mm or .001" to .003".