Noise in engine

[Guest]

Getting more noise in engine than in past (see unlucky and lucky thread). So reset cam chain tensinor, no change. Took valve cover off and snugged down cam cap bolts (broke one, why there is another thread). Got it fixed and then adjusted valves, only needed to change three and all only down one shim size. Checked cam timing it was fine. Put back together and noise still pretty noticeable (more than normal gs ticking). Decided to spray some water on the heads, and on three water sizzled away immediately, but not #2, water just rolled down for a while and finally after minute or two would evaporate. Tapped on #2 float bowl in case it was stuck. Changed plugs, switched coil wires, no change. Pulled plug wires one at a time and bike died everytime except on#2. Used my cheap ebay compression tester and got hardly anything. Checked another cylinder with tool and got above 110, so seems it is working. Plan to try to borrow good one tomorrow and retest. Guess this explains the small amount of smoke from exhaust at times and having to add oil more than in the past. Looks like time to tear it apart and see what going on in there. I'm thinking piston noise might be what I'm hearing. If have to tear apart will do new valve seals, lap valves, new piston rings( and whatever damage there may be). Leaving for family reunion tomorrow so wouldn't get anything do till next week.

[BIG_brother]

Is it a clickity clickity sound at low idle?
If so that is normal and will not hurt anything
Its cam walk

[Big T]

Bad petcock is flooding #2

Is your oil level high?

The noise is because one cylinder isn't running

[terrylee]

Petcock is oem and not more than 2 yrs. old, but I will check it But it is doing it with my auxillary tank hooked up. I did a search and doing carb sync. was suggested for this same problem. I have a morgan so will try to do one in morning. Noise is much more than cam walk. Oil level is alittle low, and not long ago I did oil change and not ridden more than 100 miles since, do have very small oil leak, but nothing to much. terrylee

[terrylee]

Ok synced carbs this morning,they were off some, especially #2. Got them almost perfectly lined up with each other (have no cross over pipe). Bike starts right up and runs very smooth and engine was quieter than it was before. But #2 is still not getting very hot, can touch header quickly without getting burned, water still doesn't sizzle off header. No change in engine when pulling plug wire. Checked and gas is coming out of float bowl when remove nut on bottom. So next week I plan to take carbs off open them up and see what might be a problem, double checking #2. And do a good cleaning. Think I'll order new float needle valves just in case. Been about 2 riding season since total rebuild. At least my fears of internal problem may have be premature.

[terrylee]

Still not firing right

Took carbs apart and cleaned all jets, blew through everything with carb. cleaner and air compressor (carbs rebuilt completely less than 2 seasons ago), everything looks good and clean and nothing blocked. Checked valves again (#2 exhaust at .09, #2 intake at .08). Got new carb. boots from engine to carbs (O-rings replaced not long ago, and still nice and round and soft), resynced carbs. Replaced coil for #2 and 3 with new one I already had. Checked coils volts, getting 11.7 and 12 volts, coil relay done long ago. New plugs. Pull #2 plug wire and bike doesn't die but does run rougher. Checked temp. of head with meter and #2 is only about 500 deg. while 3 and 4 are at 950-1000 deg. But now #1 is not has hot as it was before (around 650-700 deg.) Any ideas would be greatly appreciated, at his point since it runs pretty well, I'm tempted to pour in some seafoam and ride it! terrylee

[chef1366]

Why are you messing with your carbs when you have no compression on that cylinder?
Check for a burnt valve or broken ring.
Put some oil in the cylinder and see is the compression rises. If it does your rings are shot. If not it's a valve.

[terrylee]

Had had been reading some of the threads about the same problem and some suggested carb. might be blocked up and so not working properly and that might cause the noise and less hot head. I was afraid it might be something inside the engine, but wanted to be sure I tried everything before I tore into the engine and lose most of my riding season. Will try to do what you said tomorrow and see what happens. I was hoping to wait till winter to redo stuff on inside of engine. I've already been buying some of the oem gaskets. But sounds like I be spending some bucks, while I'm in there I want to do it right. terrylee

[chef1366]

Just a thought. Have a friend who's GS750 was making noises similar to what you describe. More importantly, with carbs and valve clearances checked and verified ok, had a 'cold cylinder' as well. Turned out that a cam lobe had gone flat.

That's very likely too! But the compression would still rise.

[terrylee]

Thanks guys will recheck compression today, drop in alittle oil if low and see what happens. Just adjusted valves, didn't notice any problems with the cams, but will look. terrylee

[terrylee]

Well, checked compression, getting 115-125 in every cylinder but #2, barely 40. Put in alittle oil and didn't change. So looks like a valve problem. terrylee

[chef1366]

Are you sure one of your shims is not too big?
Did it run ok before the valve adjustment?

[earlfor]

Pulled plug wires one at a time and bike died everytime except on#2. Used my cheap ebay compression tester and got hardly anything. Checked another cylinder with tool and got above 110, so seems it is working.

Yep, the compression tester is working and it is telling you there is no compression on the #2 cylinder. Cleaning the carbs again is not going to change that.

[koolaid_kid]

I suggest checking the valve clearance on #2 again before pulling everything apart, as chef1366 suggests. Just to double-check.

[terrylee]

I will double check the valves on #2 before anything else is done. I don't think I made a mistake on them, but I'm not ruling it out. Again only did carbs. because other gs folks on other threads had suggested to people with this type of problem that a blocked carb. could cause noise issue and the cylinder not getting as hot as the others. And did have this problem before latest valve adjustment. Will try to check valves tonight and see what I get. Thanks for all the advice. terrylee