Valve adjustment problem gsx550

[frosti2k2]

Hi all, I seem to be having a problem with valve adjustment on my 1985 gsx550(58,000 miles).

Since buying it I noticed the tappets were getting quite loud, so I checked and adjusted my valve clearances. some of them were as much as 0.22mm. I set them all back to a 0.08mm sliding fit and have also double checked them since.

Since doing that adjustment I have hard starting, poor/uneven idle, and vibrations throught the mirror at idle/off-idle. I have tried a carb sync multiple times to no avail. It seems still unbalanced. I can also hear engine noises like my carbs are still unbalanced.

Performance midrange and upwards seems fine, but idle is not now. After bike warms up, the idle rpm creeps up but also sometiimes it goes down and dies. If I blip throttle I have a bit of hanging before returning to idle.

I have also had problems with brown/yellow jelly substance in petrol tank that also keeps sticking my float valve closed, perhaps this is causing something at the same time as valve adjustment?


Any ideas why setting my valves into spec could be causing me problems?

[gustovh]

Drain and clean the tank, gas valve, lines and carbs. Valve gap closes with wear not open up.
V

[frosti2k2]

I have drained tank twice and lots of this jelly came out, what/how would you suggest I clean it with?

Whichever way valves change during use, I checked and adjusted them and they were set too loose so I set them back to 0.08mm.

I wonder if my choke is stuck open at all, or perhaps are there any problems that can be made worse by setting the valves correctly? For example would the effects of an air/vacuum leak or leaking exhaust gaskets be made worse by setting valves correctly?

Does correct valve clearances make the bike more fussy to carb setup/tuning?

It seems setting the valves too loose makes my bike start easy and able to balance my carbs properly.

[DimitriT]

You did check them on a cold motor right?

Be aware that clearance increases as the motor warms up
so if you checked them on a warm motor you are way too
tight when the motor is cold. That would explain the hard
starting.

[frosti2k2]

Checked cold, as per the suzuki shop manual/haynes procedure.

I have also double checked them and there is definetly clearance there at cold.

Checked spark plugs this lunchtime and they are all white, with the faintest brown marks on insulator, hardly noticeable. So indicating that I certainly dont have idle/stalling due to richness.


Have been reading about the intake o ring replacement, as I dont know the history of the bike, it might be my next step. Certainly bike seems lean. I changed the exhaust-head gaskets yesterday and the middle two pipes had white deposits looking down into the pipe, and also what I could see into the head looking at the valve stems, these all had white deposits on them, perhaps another sign of too lean??

[Nessism]

The problem is almost certainly that crap in the gas tank, not the valve adjustment. As Gustov already mentioned, drain the tank and clean it out. Sounds like you may need to seal the inside, not sure. The archives is full of info about tanking sealing so do a search if you need help with what to do.

[Larry D]

Certainly sounds like it's lean. If the rubber boots/clamps and airbox are sealed well it's more than likely an air leak at the intake o-rings. This should be addressed quickly before something worse happens. A ongoing lean condition can cause some catastrophic failures.

Lining a tank is an easy, although time consuming project, follow the directions to the "T". Putting a splash of Seafoam every other tankful will help in keeping the carb from gumming up. You may consider getting your gas from another station.

[frosti2k2]

Thanks for all the help.

The jelly in the tank seems to be a problem that was there when I bought the bike already. It was left unused for two years and someone most probably didnt store the bike properly, and left petrol in the tank. Its liquified enough to pass through tank filter, through in-line filter, and through float needle seat filter. But then it turns hard and blocks my carb up.

I forgot to mention, when I am draining the tank out as I get towards the bottom this jelly stuff starts continously streaming out. It always easily settles to the bottom, and the petrol stays on top. The more I drain it the more it seems to come back.

Will try to get some pictures ?

Hoping that valves are not burnt already as the stems looked very white and had some black colouring around the point it meets the seal

[twiggy2cents]

a hot engine has less clearance than cold

[TheCafeKid]

a hot engine has less clearance than cold

Ideally, probably so. But the problem is that the expansion rates at different temps are not KNOWN constant, especially considering the different alloys used within the parts. As such, the only PROPER and semi-consistant and accurate way of checking and adjusting clearances is on a stone cold motor.

[twiggy2cents]

You did check them on a cold motor right?

Be aware that clearance increases as the motor warms up
so if you checked them on a warm motor you are way too
tight when the motor is cold. That would explain the hard
starting.

sorry i was stating this for correction

[twiggy2cents]

also the problem with adjusting them hot is that when you started you had a 190* motor and when you get to cyl 3 it could be at 150* or lower

[Roger P.]

You also burn your fingers.

[twiggy2cents]

yes that is an important part too

[DimitriT]

sorry i was stating this for correction

np. I thought it was the other way around.