Bronco TECH for my 4 Bt

[Pa PITT]

So any one have any diesel advise.
My 4BT Ran great for 10 years . But I had issues & I've got it running much better now But IT still has some issues.
Now I've driven it about 5 times for say 45 minutes at a time .
1ST TIME it ran good for maybe 30 minutes then it started rumble or a rolling idle for maybe 2 minutes . Riving it up & down it cleared up .. But bad Idle came back ..
.2 ND TIME IT ran for a while maybe 25 minutes surging or rolling idle
...3 & 4 th times it ran for about 30 minutes & Idles gets rough almost llike it has a cam in it .
Next time I started it in sho & left it running in shop at only about 900 rpms & It was really rolling & LOPING. rIVING IT UP SEVERAL TIMES & it cleared up & I drove it for another 30 minutes & it =had a bad idle about 2 more times .
.. Only thing I CAN THINK OF IS TO ADD some 2 cycle oil & see if that helps
we added it when I worked at Chrysler .
..........................
.... One older tech says it a bad Injection pump . But this one
has been rebuilt & I installed it during the time this it's been having issues .
& Now I have a new set of issues with this new injection pump.

 

[73azbronco]

I'd try another diesel type forum maybe, not sure more than 3 or 4 of you high compression guys living here:0

 

[savage]

Take a temperature gun and aim it at each exhaust port to see if you have a cylinder going bad or a injector not working properly. Have you changed the fuel filter?

 

[Pa PITT]

EVERY THING IS NEW I just got it running again. It stopped running about a year ago. Some one came to my place & pUT SAND INTO MY fuel tank.
I've put a new fuel tank on it .. A member here sent me his old tank after he'd put on a 23 gallon tank.
...I took the new tank to radiator shop & had it boiled out.
... I put in 40 new injectors .
... I put on a new injection pump .
... BLEW OUT FueL LINES.
... PULLED LINES FROM INJECTION Pump to injectors & blew them out .
.. Put some new line on .
... & Put on new filters twice ..
... & I believe this is 99% of what I've done .
... This has really been a problem .
.. & I can't imagine who did this . I guess they stole a stereo out of my motor home .
But I have 7 roll around tool boxes setting in my shop. & nothing else seems to be missing . Had to be kids & just meaningness .

 

[savage]

Did you discover the sand in the tank before attempting to start it? I would still take a temperature gun and check each cylinder, to see if you have a cylinder going bad. Even new parts can go bad. Good luck.

 

[Rustytruck]

need some bear traps just don't forget where you put them. once the scum come they keep coming. they don't travel very far so easy to find them. set out your game cameras. what the hell are they going to do with a 20 year old stereo when their cell phone does a better job? sound more like a 40 year old tweeker. its tacos fault get on his ass or get a doberman. will need a bigger Lair on the door though.

 

[73azbronco]

sand and dirt should have all been stopped by the filter. Unless they put sugar or something in it.

 

[Boss Hugg]

Did you check the filler tube while you were cleaning all the sand out?

It's also possible that a new or rebuilt injector pump is not quite right. Sounds like something may be loose inside it? I'm going to tear into a pump on a 4500 ford backhoe soon with the help of YouTube. Tractor had a stuck clutch so it was pretty much parked until we could split it open and rebuild all that. Recently I came on to the idea of drilling a hole in the bell housing and using a screwdriver to crack the clutch loose. But the tractor needs to crank first and it sat so long it's not passing fuel thru the pump.

 

[bigmuddy]

Pa, I sent you a friends number via PM. He works on the 4bt and who is a fellow bronco nut.

 

[brewchief]

Do you have an air leak in the fuel lines from the tank to the engine? I'm thinking that it uses a mechanical lift pump on the engine, it's possible to have an air leak that will leak air in under vacuum but doesn't leak fuel. A rubber line that's failing internally could do the same thing.

Sent from my SM-T510 using Tapatalk

 

[Pa PITT]

When we replace the tank we clean every thing .. I poured out about 2 qt's of sand .
None of the ones around me at that time thought I had any sugar ..
That was my 1st thought .
... Funny thing was for the last 40 years I've been told these motors could run on any trash . Well that's B/S . But we did a lot of cleaning & one of the members here sent me his old tank & I cleaned it twice now . ...
One of the cyl could be going down ...But I believe this new fuel leak on the no. 3 injector . & I may order a new injector but I'm also on the hunt for a new Injector line .

 

[savage]

What injector pump do you have ? Vp44, p7100 or other. I would think it's a P7100, if that's the case, you should be able to use a injector line from it's big 6 brother, only difference is yours has two less cylinders.

 

[Pa PITT]

No mine is the VP44 Rotary pump .
...........
.... i WAS told by a tech in town that the Rotary pump is worse at developing the rolling idle.