JD 450 Loosing power and then stalling

[BlackDog]

I have been chasing this issue for several months. The machine would run fine for a little while and then loose power no matter what I did with the throttle. I would have to crack the lines on the injection pump to get it started again. Well my thinking was that it is a fuel problem. I drained the tank and cleaned it. Checked all the fuel lines. Replaced the filters and fuel pump. After all that it still did the same thing. So I bought a rebuild kit, and me and my buddy who has rebuilt many pumps. We rebuilt the pump and reinstalled it. Got it running again but sounded like it was missing and was getting a lot of white and blue smoke. Also had several leaks from the pump that never had before. We had replaced all the gaskets and seals. I have no idea why they would be leaking. I am thinking about taking the pump off again and sending it out for a rebuild. Was looking at getting some opinions on this or maybe there is something that I am missing. Any suggestions on who to send the pump out to?

 

[lantraxco]

Check the return fitting with the glass check ball and spring does not have debris packed in blocking the return.

Double check your pump timing.

 

[thepumpguysc]

Depending on the pump model.. Remove the return connector, top of the pump and blow it out..
That's not going to help w/ the leaks tho.. Post the pump # off the name plate..
Did you time the pump/engine before taking it off??
Did you remove and clean out the fitting in the bottom of the tank?? you know the one w/ the screen in it..??
I"m available if your going to send it out..

 

[Don k]

Did you actually remove the fuel tank and pressure wash it? To me it sounds like you had something floating around on the bottom of it and would release itself when the engine quit. I would either send your injector pump out or get a rebuilt one. I would remove the fuel tank and pressure wash the inside. I would remove the small screen in the tank and install a inline fuel filter at the tank. I would remove the JD fuel filter and blow out all the lines after disconnecting the lines to the fuel pump. Then install a new JD fuel filter. You had some trash in somewhere and if even a small speck of it gets into the injector pump it is toast. How do I know? I screwed up one time and did not do what I told you to do.

 

[mred]

I had a problem like this. It was the vent in the fuel cap. By checking the drain at the fuel filter, I could hear air being pull back in. Agree send the pump to be rebuilt.

 

[BlackDog]

lantraxco, Where is the glass check valve located?

 

[BlackDog]

Don k, I drained the fuel tank and pressure washed the entire tank. I then blew out all of the lines and changed the filters again. I also installed a new fuel pump.

 

[BlackDog]

thepumpguysc, The pump is a Mesa Roosa model JDB435AL2442, we did time it before removing it. What do you think it would cost to get it rebuilt?

 

[thepumpguysc]

PM sent.

 

[lantraxco]

lantraxco, Where is the glass check valve located?

It's in the return connector fitting screwed into the top cover, as The Pump Guy mentioned. Disconnect the return line and then unscrew the brass fitting from the top of the pump.

 

[thepumpguysc]

Yup.. its the very 1st fitting coming out of the top cover of the pump.

 

[thepumpguysc]

Theres acouple of things that could be causing the white smoke..
Is it hard to start.?? REAL HARD.. then tons of white smoke.??
If you put the drive shaft in 180* out of time.. that'll do it..
JD engines WILL RUN 180* out of time..
Just because the lines were in the window DOESNT MEAN you put the weight cage on right.
TO BE SURE.. Tie the throttle to wide open..remove the pump. put it on a table.. looking at the back of the pump.. put constant air pressure in the port at 5:00 on the pump.. now using a long, wide blade screwdriver, {WITH AIR STILL BLOWING IN THE PORT AT 5:00,** where the drive shaft would go, spin the guts slowly in a CLOCKWISE direction until the guts stop moving..
The lines SHOULD BE in the window BY THE NAME PLATE..
IF NOT.. the weight retainer w/ the line on it, is on wrong..

If you assembled the advance mechanism wrong.. that'll do it..
The adjuster screw on the advance mechanism, should be on the name plate side, not on the engine side.

 

[BlackDog]

Had some time and the weather was nice so I decided to play with the dozer and see if I could get it running. I had removed the check value and cleaned it. Thanks thepumpguysc and lantraxco. I cracked a injector line and it fired right up. Ran for about a minute and died out. So I removed the hard return lines and the soft lines and clean them up. I then removed the soft line returning to the tank to see if I was getting fuel through the system. I fired it and it ran great, well I thought. I had it running at idle for a good 45 minutes with no issues. So I reconnected the lines and moved the dozer around the yard a little bit. I have a couple issues now. It will stay running and starts fine. But when I throttled it up I can only get it up to 1100 RPMS? I played with the throttle arm and tighten the screw but it did not seem to have any positive effect. The other issue is I still have a small leak out of the bottom of the pump where that round electrical connector is. I tried replacing the seals with no luck.

 

[thepumpguysc]

Sounds to me like the flex ring inside the pump has broken and is getting into the return lines.. low to no power, white smoke..
You better not run it like that or you wont be able to control the engine rpm's and it wont shut down..
From your picture, it looks like the pump has never been rebuilt?? they haven't used a wire ground strap since the 70's..
BUT you said, you & your buddy took it apart & overhauled it.. God only knows what it could be??
Seeing its only running 1/2 speed, right off the bat I'd lean towards the cam ring inside the pump being in backwards..??
Seeing the pumps been apart its anybodys guess..

 

[BlackDog]

So it looks like it needs to be taken apart again? Thepumpguysc I think you might be receiving a package very soon. :Banghead

 

[dillon45]

This could be a long shot, however, it could be electrical (most likely in the key switch) such as a ground, or a wire shorting out. I had a similar problem with a JD tractor several years ago and thought it had to be a fuel problem. It turned out to be a ground on the key switch which caused the symptoms you're experiencing. By pass the key switch directly to the injection pump. I spent days and many dollars, and all it needed was the ground wire cleaned from rust.

 

[DMiller]

Been down this road on almost every engine with a Stanadyne or Roosa Master style pump, Always the coupler failing in the pump putting trash in the return fitting. Overpressures the pump housing and forces a fuel shutoff. Get the engine up on number one TDC, timing marks in the window and take the pump to a rebuilder. My Allis 180 has the same style pump was around the $600 mark to go completely thru.