So this is how this form works someone asked a legitimate question people with knowledge try to help troubleshoot and answer questions. Then you have someone that doesn’t even know what a 46 a machine is and they gladly give their opinion it just confuses everything why? No response Necessary thank you.

"Skinner" wrote:

So this is how this form works someone asked a legitimate question people with knowledge try to help troubleshoot and answer questions. Then you have someone that doesn’t even know what a 46 a machine is and they gladly give their opinion it just confuses everything why? No response Necessary thank you.

I am guessing you are talking about me?

I am pretty sure I made it clear what my knowledge was in my post and what a person does with what I said is their own business.

However, I also saw lots of people suggesting to change the fuel filters when it was never established that the engine was bogging down or beginning to stall. Unless the fuel filters somehow tie into the clutch/transmission?

Everyone that gets information from this site or anywhere has to be careful how they use it and they have to be sure it applies to their particular tractor.

Being knowledgeable or not, I have to question the fuel filter advice people are giving because it sounded, to me, that it would be a waste of time and money to replace the fuel filters to fix what sounds like a clutch/transmission issue.

Hopefully the advice people have been giving will help solve the problem.

i think the problem is that the clutches in the powershift are slipping because of low transmission pressure. could be internal leakage.

This Tractor has a diesel torque converter, hence why it was suggested to change fuel filters as flow of diesel to the converter may have been restricted and caused it to slip more than usual. The supply is the same fuel tank etc as to the engine.

It does appear to be a low transmission charge pressure issue that the pressure gauge is indicating low pressure, can be a number of factors as already mentioned such as blocked oil filters, blown O ring, fractured pipe, stuck relief valve, worn pump etc. Due to mechanical advantage maybe 1st gear is not slipping at all or as much and the other two speed clutches are. I would follow with the suggestion of changing filters, cutting open the old filters to see what may be in them, checking the magnetic screen(s).

To start pressure testing to try and isolate loss of pressure you would be best to obtain a service manual so that you can follow the test directions etc from it.

Wombat

The D8H is power shift and should have a oil torque hydrolic

Do you have some pics? Machine could of been upgraded to a hyd torque ,pictures would show what you have.Its a guessing game at this point.You have to get some manuals, they are not expensive, I can,t understand people not to have information on their particular piece of equipment. There are people on here that are here to help you out ! But you need to give them as much help as you can.Pictures are worth a thousand words

"Wombat" wrote:

The series tractor you have has a diesel 3 stage converter followed by a 3 speed powershift transmission. I suggest that you lift the floor plates so that you can watch the driveshaft between the converter and the transmission. If when in gear under full revs the shaft comes to a stop when held with the brakes then that transmission clutch is ok, so systematically go through the gears and forward and reverse to identify if you have slipping transmission clutches or a torque converter problem. This is the most basic test for troubleshooting the issues you are having, will narrow the window of what could be the problem. The transmission only has 5 clutches, 3 speed clutches and forward and reverse clutches.

Wombat

Hi Team,
until we hear back as to the T/C to Trans. drive shaft status we can offer no more meaningful help.
This will help us decide as to whether we are dealing with a Transmission problem or a Torque Converter problem, or both.

If it turns out to be simply bleeding air from the T/C to get it working properly again then I will post scans on the procedure here --I posted them for a D8 35A 3 stage Fuel T/C tractor in the last week for any who wish to check it out.

Troubleshooting has to be done in a logical sequence or you can end up pulling out a big component when it was only requiring a service of the trans pump suction line filter screens down in the front of the Powershift Trans. case on these early units.
Clogged Trans. pump suction screens can be caused by crumbling steering brake band linings on a machine this old--a not unknown problem as I have done a few machines that had this occur.

Troubleshooting scans below are from the Cat Of Australia Powershift Transmission 1, School hand out notes I did in Oct. 1965. Sorry they are photocopied notes.
Cheers,
Eddie B.

So tracing lines reveals there are 2 pumps attached to the transmission housing. One on the right hand side of the machine, one on the left hand side of the machine. Each has there own suction line and filter housing. I removed both filters. One on the right hand side of the machine looks really good. One on the left hand side of the machine had a hole right through it that kinda resembled like a 22 bullet hole appearance. I am assuming that hole must of been caused by something letting go in the pump it is attached to? I pulled both suction screens on the bottom of the transmission. The one on the left was spotless, the one on the right hand side was completely clogged with what appeared to be clutch plate or brake lining material. So from what I can take from this is the reason I had low pressure on my transmission is that one pump was struggling to get oil due to a plugged intake screen. The other pump likely has something wrong with it due to the bullet size hole it put in the filter? I am trying to attach photos to try and help with my description. Thankyou

Not out of the woods yet, The suction screen on the right is for the steering clutch and brake circuit only. The suction screen on the left is for the transmission circuit. Need to get a pressure check on the transmission pump. Should be in the 300 to 330 psi range.

could be you have two problems. low oil pressure ...assuming the gauge is good and reading accurately. and possible your steering clutches have failed?