Andyinchville

HI Guys,

I recently went to michigan to buy a step van (ex bakery truck)with a 4 BT cummins to use in my business in VA.

I have since been broken down twice and have had to be towed twice since getting the truck (I am now in a motel in Monroe Michiogan).

The truck is a 1981 chevy p 30 chassis w/ a 16' grumman olsen body. It has the 4 BT cummins engine and auto tranny. Per the owner the truck was repowered about 40000 miles ago (with the 4BT by the bakery that previously owned the truck)....I am not sure of the rear end ratio but the truck has a 10000 factory GVW rating so it is probably geared low but not as low as it would be if it were a higher GVW vehicle).

The previous owner had the truck 5 years but never titled it and only ran it some here and there.

The engine starts fine and accelerates OK until about 45 MPH (occasionally it does feel like the engine begins defueling and sometimes it can break into the 50 MPH range.....

I purchased the truck and was going to go back home to VA when all of a sudded the truck died....no stumbling or smoke...just died like somebody turned off the key (in all fairness it may have felt like it was defueling before it dies but I was only at about 45 or so mph).

I pulled over and got towed to a cummins dealer where they bled the lines and replaced the fuel filter and sent me on my way (I did mention to them that the truck did not shut off immediatelty a couple of times when I turned off the key....they said it may be a faulty shut off solenoid and I ended up buying one "just in case" but they did not install it because they figured I mught be OK since it was running fine (at least idling)

I got the truck back and started my trip back home....the truck died again and I was towed a second time (I was only a mile or two from the cummins dealer but did not want top go back there since they charged so much and did not solve the problem)....As a side note the truck only made it to about 45 mph or so before dying the second time.

I had the truck towed to another shop. They checked for fuel in the fuel filter and saw it was OK (filled but not leaking when they unscrewed the filter). They tried rehooked the line (wire) to ther fuel shut off solenoid (it appears to have fallen off....they did mention that there looked like there were some other unhooked wires but they did not know what they were for....is there some wire to let the IP know the engine is warm to allow for more fueling and or allowing the engine to reach higher speedes once warmed un?)...

Anyways, they bled the back two injectors and the engine fired up (should they have bled the front two cylinders also?....the engine runs smoothly tho....is it possible or safe to bleed the front 2 injectors by cracking the line a bit while the engine is running?....I saw how to loosen the fittings so I could do that but a friend (not necessarily a guru) said it may be dangerous to crack the lines while the engine is running because of the high pressures involved).....also, I wonder if there may be a little air in the system because sometimes the engine will start warm with just one quick bump of the starter....other times it takes a little while (engine warm).

My dilemma is the truck now runs BUT it maxes out about 40 to 45 on the highway whereas it used to max higher....sometimes on the highway I was only doing 35 MPH.

I filled the tank and used 20 OZ of diesel kleen (or was it Diesel power)...in any event it was cleaner for the fuel system (it has not helped alot yet but I have only driven it 7 or so miles with the cleaner in it before calling it a night at this hotel....maybe overnight the cleaner will work its magic?).....oh the filter the cummins dealer pulled out looked clean per the tech but they changed it as a matter of course)....As a side thought is there a filter sock in the tank that could be gummed up not allowing full fuel flow to the engine?

Is there an easy adjustment that can be done to get her to run more strongly and at a higher speed?....I worry because I am on the flats and going about 40 to 45 and have yet tro hit the hills in West VA....

I am typing from the hotel computer and I will check back here later tonight or if anybody can call me on my cell phone that would greatly appreciated....
My cell is 434-760-6924.

Thanks for looking at my long post and thanks for any and all help in advance.

Andrew

wannadiesel

I would guess bad lift pump or if there is a some kind of restriction (suction strainer, primary filter, kinked fuel line).

Nothing wrong with cracking lines while the engine is running, just don't let the fuel spray you.

This is a VE or inline pump?

Andyinchville

Hi Dave,

Thanks for calling me BUT I tried calling you but the nimber I got (or at least wrote down does not seem to work....Could you please try calling again?....

I tried to look on my list of recently received calls but I guess reception was not the best so you must have gone directly to voice mail and not in the log of received calls.

Thanks!

Andrew

Andyinchville

HI Wannadiesel,

The pump is a rotary pump not the P Pump.

Andrew

Andyinchville

Thanks for calling me again Dave....I will try your suggestions this morning.

Andrew

j-fox

Make sure that wire on the shut off solinoid is tight.
If it has been sitting for much time, change those fuel filters--again!

find the screw that adjusts high idle--max throttle, no load, and turn it out one turn or so. This is your top speed adjustment.

Andyinchville

HI Guys,

Just thought I'd day thanks for all the help.

I did manage to get back home today around 1 AM and 3 tows later!

The tow truck driver during my last bout of tows was even so nice as to follow me ( his wheel lift was broken but he came out anyways to help)....he seemed to think it was a plugged filter sock / screen inside the tank itself....he went so far as to disconnect the fuel line and blow back into the tank to try to free it up but alas it did not work and I ended up on the side of the road 3 times as he tried different things)...

We ultimately got home by calling a tow truck from my home town to rescue us about 70 miles from home.....fortunately through the efforts to of second to the last tow truck driver we got within the 100 mile service limit of my AAA plus RV towing service.

I will take a few days now to thoroughly fix up the ol truck....I plan on dropping the gas tank (err diesel tank) and thoroughly cleaning it out, I will remove the fuel sock if present and add another external filter to eliminate the need to check out the inside of the tank for potential problems....Alot of the fuel lines look old so I will replace all the lines with new rubber lines.

Thanks for the tips on needing to replace the filters again and the top speed adjustment....I think I will do that just in case and check the other....it would be nice to be able to hit 55 mph on a sustained basis.

I have a new fuel shut off solenoid just in case but I may end up converting to a manual fuel shut off (I will use something more HD and durable than a simple choke cable like on my other truck....That should help eliminate another possible problem.....I need hard core reliable since the truck will be a daily driver.

Thanks again.

Andrew