Tram issue on 422

[SwampmanLA]

Update from Terry: the tram pump has to be pulled and sent to PT for repair. Swapping the control lines tested the treadle valve and he knows it is something in the pump. Well looks like I have a project for the weekend.

 

[MossRoad]

My condolences to your knuckles in advance.

 

[cqaigy2]

Be sure to plug your lines cause you don't want one to fall down below the level of you tank and drain 10 gallons of oil onto the floor.

 

[ponytug]

Besides, you want to keep sand and dirt out of the lines...
All the best,
Peter

 

[SwampmanLA]

Cleaned the tub out very well so dirt is not an issue. Numbered all lines and took pictures as I took it apart. Actually taking it out was easy. The prep took all the time. Tram pump gets shipped in the morning.

 

[Poorman1234]

As anyone had a 4xx with hydraulic tram pedals just keep moving when you let off the pedals? My 2008 vintage 422 just started doing this, when I release the foot pedals it keeps rolling and slowly comes to a stop. Some opposite pedal pressure will stop the PT with no problem but the run on is new. I cleaned the muck out from under the floor boards, lubed the pedals up real good, but it still has run on. Tram still has plenty of power so I do not think it is a pump issue but a tram value issue. Ever heard of the tram valve failing on a 4xx PT?

My vintage PT-422 has two return springs in the pump control cable that runs between the treddle and pump. It is encloded in a black platic housing about 2" in diameter and 4" long. It povides a spring return force in both directions.

As with all springs,,,,they weaken with use. Further, as the inevitable decay with time, the cable moves less freely as the lubrication escapes or wears. Weeker spring and harder cable pull both work to make it harder for the pump to center.

Check cable lubrication as well as the springs in this assembly.

 

[MossRoad]

As was mentioned earlier, the OP's PT doesn't have a hydroback cable. It has the newer hydraulic valve treadle instead.

 

[SwampmanLA]

Well Terry called with the results of my tram pump post mortem. Seems that a spec of something got in the closed loop system of the tram circuit and scratched a plate in the pump. It is all fixed, boxed up, and hopefully on the way back to me. I have no real idea of what they changed in the pump bug all I really know is it cost a grand to fix. Ouch! I love my PT so I would have paid more to get her back running. I just hope she stays fixed for a long time.

 

[PTWannaHave]

Ouch indeed...! I have to wonder how much a local hydraulic shop would've charged to service that pump...

 

[SwampmanLA]

And the saga continues. Got my repaired pump back and installed. Found that I had reverse but no forward motion. A few calls to Terry and all he could say was to send the pump back to him for additional inspection. So I pulled it and boxed it up today.I hate being without my PT but right now I have no choice.