350b dozer

[jon dere]

hi i put new reverser clutch discs in my dozer i put it back together and i have no pressure on the clutch side but good pressure on the cooler and relief valve side. help i had it before

 

[JDemaris]

I assume you did more then just put new clutches in? There are many parts inside there that can be worn, missing, or broken to cause no clutch pressure. Piston seals, collector assembly, delvery tubes that connect the control valve to the internals of the clutch packs, pump, oil restrictor in the input shaft, etc. Are you saying you went through all the work of pulling the engine, then the reverser, and didn't replace anything else?

Did you stick a pressure gauge in the main clutch-pressure test port and check it?

 

[jon dere]

pressure in all ports was fine before replaced all seals and bearings along with discs

 

[JDemaris]

Yes, and what is it now? There are two test ports under the floor-board. One is lube-pressure an should be 20-30 PSI. The other is clutch pressure and should be at least 120 PSI. If a later wet steering clutch machine (350C or newer) it should be 150 PSI. It should be there in neutral, forward, and/or reverse as long as the clutch pedal is up.

 

[Roy Suomi]

The 2 test ports on the control valve are as follows; drilled straight down is main pressure port....The one drilled at an angle is the lube port..I also made an adapter to power up a reverser with a STRONG 1/2" drill..I took a spline from a clutch center that fits the reverser spline , welded a stepdown to fit a drill motor attached to a short section of pipe welded to the clutch center..Loop the cooler lines and hold the clutch pedal back against it's stop..Find a fleshy friend to run the drill while you work the forward , reverse lever on the control valve..Drill will spin it up fast enough to get full pressure readings..It will also give you a chance to check for leaks before installing the reverser into the machine..

 

[jon dere]

i have lube pressure and cooler pressure but zero clutch pressure WHY?/?/?

 

[jon dere]

very good idea.i have no pressure on clutch side

 

[JDemaris]

I can only guess and need more info.

Do you have no pressure in either forward or reverse?

Before you took it apart, you DID have clutch pressure, correct?

If so, I assume you did not take apart anything in the control valve assembly, and just removed it in one piece, and put it back on without touching anthing inside?

If that is correct also, then it has to be assumed you did something along the way to cause no pressure.

Are you sure you put the devliery tubes back in correctly with o-rings - that connect that control valve assembly to the clutch packs collector inside the reverser case?

Pressure comes from the pump - which is pretty hard to put in wrong.

Goes from that pump to the control valve assembly that I assume you did not touch internally.

Then pressure leaves that control valve assembly, down one of those steel delivery tubes and into the reverser case.

From there, it enters the collector and clutch packs that you said you DID have apart.

Somewhere in all that, you've got something wrong. Without knowing exactly what you did, or did NOT do, it's pretty hard to tell from here.

I've never put one together had a no-pressure situation. Low when hot, yes. Leaks, yes. Probably the most problematic part of the job (and most gotten wrong) is getting the bearing adjustment correct on the input/output shafts.

About your clutch packs - were they cast-iron ringed at first, and did you replace any with rubber rings?

Now, if you DID pull anything apart inside that control valve - there are many things to cause a no-pressure situation.

 

[jon dere]

thank you no I did not replace any of the pressure rings nor did I take the vavle body apart just off in one piece put the tubes back in o ring ones on top and bottom steel one with the ring in the middle yes I had pressure before on all sides but now just no pressure on clutch port I thank you in advance for your help.