hot cylinder york comp

[jase in space]

hi guys any help/suggestions would be great
I have a york JG843-T46/50S style compressor with 8 cylinders running on R22. head one is constant loaded with other 3 heads loading heads. on the top of head 2 the paint is blackened and burnt with the cylinder on the motor side the obvious culprit. the comp which is stage 2 of 3 sits atop a YorkYCWJ999XX. I have just put comp back together after doing a top end haul changing all springs (old style- not wave spring) and rings and now said cylinder is running hot (40*c more than other cylinders) the said cylinder was not running any hotter than the others on average before spring/ring change. opened head back up today and nothing obvious stood out, rings springs and cages all set ok and torque set. the cylinder wall wasnt even darkend. am stuck for ideas please help before I use my extra big hammer on stage two

[Grizzly]

Did you check the operation of the unloading pins, whilst you had the head off?
Also when re-stripping the Valve assy. Did you notice whether you had pinched the Suction valve plate.
Because that would be the most obvious cause.
And yes even experienced guys do this from time to time.
Grizzly

[GHAZ]

hi check your discharge plate seat and suction plate seat were the ring valve sits ,and make sure they are flat and scratch free ,and discharge carrier is not worn i.e the ring valve is not loose in it, it also could be possibile that the unloader is passing hot gas through, because the jg compressors work on suction gas cut off by using the discharge pressure to press the suction cut off valve to shut the crankcase off to the cyclinder .and the unloader valve it self might be worn,so when it loads up the the solnoid valve might pass hot gas down the chamber. to check it its pretty straight forward , take the solnoid plate off on top just pass the head ,and the unloader valve should pop out on its own with the spring pressure underneath it ,if it doesnt then clean it up inspect it ,or replace it ,

[RANGER1]

Did you check the operation of the unloading pins, whilst you had the head off?
Also when re-stripping the Valve assy. Did you notice whether you had pinched the Suction valve plate.
Because that would be the most obvious cause.
And yes even experienced guys do this from time to time.
Grizzly

Grizzly your to nice .

Also I have said it before & I'II say it again , you have to manually jack unloader pins down after checking all above before assy of suction valves .
After assy use a mirror & torch to check function & seating of valves .
If it has had pinched valves in the past you will have to check for damage as it may inhibit valve function .

[Grizzly]

Hi Ranger.
There speaks the voice of experience I believe?
It's always nice to bring people down gently, is it not?
Ghaz your comments would be valid, only Jase does state that the high head temps only arose after his first rebuild.
(that is assuming only a top end overhaul was carried out?)
So logically as ranger states.
The issue is likely to relate to the suction or discharge assemblies!

Grizzly

[jase in space]

thanks guys lots of good ideas for me to check today, how ever the suction and discharge valves are set correct but will deff look at unloader. grizz the top haul was the only thing done to the comp except a new oil pump was put on and one piston was changed ( NOT the cylinder that is now hot) and of course new york C oil.

[jivan]

hi jasee i think there is problem with discharge bypass saftey valve.generly york comp. has dich pressure safty problem.

[GHAZ]

Hi guys the JG compressor doesnt have any unloading pins around the cyclinder,it only has a solonoid valve and a large piston past the heads close to the motor end , to do a top end on an ordinary york compressor with lifting pins is you pull the liner about 5mm up and the pins drop down and then put your plates on and tighned it down as you torqued it down the pins help to keep the ring valve in position.

[Grizzly]

Hi guys the JG compressor doesnt have any unloading pins around the cyclinder,it only has a solonoid valve and a large piston past the heads close to the motor end , to do a top end on an ordinary york compressor with lifting pins is you pull the liner about 5mm up and the pins drop down and then put your plates on and tighned it down as you torqued it down the pins help to keep the ring valve in position.

I stand corrected Ghaz.
You are indeed correct, I have just checked my J comp details.
I thought i had worked upon all types of J comp?
Obviously not a G style.

Please disegard my comment about the loading pins
Jase!
And tell us how you get on?
Grizzly

[RANGER1]

Sorry , looks like I'm a one string banjo .

[Grizzly]

Sorry , looks like I'm a one string banjo .

Everyone hits a bad note occasionally.
Except those that never do anything in the first place!

Grizzly

[al]

A piston was replaced, obviously faulty? is it possible you now have a good functioning compressor short of gas? just a thought..

alec

[yorkman_gr]

your constant load cylinders on this compressor is above the carter cover looking the compressor form the oil pump.
to me seem that u have trouble with the internal relief valve, typical York J compressor trouble, and i suppose your end compression temperature is above 95C and your oil too, if everything else is correct i advise to chance the relief valve, if u don't have that spare part u can try this.
Just get 1inc plug remove the relief valve and place this plug, run the compressor watching very close your discharge pressure and check the temperatures on the cylinder heads
If the compressor have two relief valves take both out and place the plugs. this test is only if u have done the rest correctly and u still facing high discharge temperatures.
good luck

[yorkman_gr]

your constant load cylinders on this compressor is above the left carter cover looking the compressor form the oil pump.
to me seem that u have trouble with the internal relief valve, typical York J compressor trouble, and i suppose your end compression temperature is above 95C and your oil too, if everything else is correct i advise to chance the relief valve, if u don't have that spare part u can try this.
Just get 1inc plug remove the relief valve and place this plug, run the compressor watching very close your discharge pressure and check the temperatures on the cylinder heads
If the compressor have two relief valves take both out and place the plugs. this test is only if u have done the rest correctly and u still facing high discharge temperatures.
good luck

looking the compressor for the pump left carter cover