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Discussion Starter #1
I bought a food truck with a 4BT and plenty of heavy equipment to slow it down. Zero experience with 4BT or diesel engines prior to this.

Is this normal? ...Uphill expressway on ramp - 30-35 mph top speed. only reaches 50mph+ downhill. (I probably have atleast 10k lbs in this truck.) Drives like a tractor more than a truck.

The past week:
-Squeaky belt
-Loss of power while driving - engine stays on for 10 seconds then stalls after I lose throttle.
-Had to jump start this morning - battery is new. No apparent draws. good voltage.
-Coolant is gone.

Do these symptoms sound familiar to anyone? I'm not sure where to start, but would like to try fixing this myself before sending to a shop.


1,530 Posts
"Coolant is gone." - Need to find out where it went :

1. Leak in radiator, heater, water pump, hose, etc
2. Into the engine - Check your dip stick, is the oil the normal black color and consistency (good news) or does you dip stick look like a chocolate milk shake (bad news).
3. Out the exhaust pipe - not quite sure how to diagnose this on in a diesel

So many possibilities on not running right - Maybe give us more info, such as the year , make and type - for instance 1986 Ford Grumman bread van. Does the 4bt have a VE injection pump (rotary) or a P type injection pump (inline)?

Some of the cheaper stull that can go wrong:
Bad or partially plugged electric fuel shutoff solenoid - Mine had an intermittent wire that powered it
Plugged up fuel filter
Water in fuel filter
Worn out fuel pump

Getting much more expensive:
Blown head gasket (likely if the lack of coolant overheated the engine)
Worn out (or rusted up) fuel injection pump
4bt at the end of it's service life
and a whole bunch more

Did this truck ever run right while you owned it?

Lots of good minds here, we can only guess with the data you have provided

11,353 Posts
Russ has covered a lot of possible issues. These vehicles are not speed demons. Top speed on the highway is only about 50-55 MPH. They were mostly delivery trucks that spent most of their time running 35-45 MPH. 10,000 lbs in the truck is probably got it's load limit maxed out. Is it automatic or manual transmission? Lack of power can come from a lot of sources. A bad turbo, bad injectors, bad injection pump, or a combination of several of those plus a generally worn engine in need of rebuilding. Loss of coolant is never a good sign. Simple causes like leaky hoses, freeze plugs, water pump, heater core, etc are the first to check. Blown head gasket can certainly be an issue. Like Russ mentioned, the cutting off issue can be electrical or it could be a bad lift pump rearing its head. Which injection pump do you have on the engine? VE or P? Clogged fuel filter can be part of the fault too. You mentioned a jump start. What size battery is in the van. It takes a big one to spin a Cummins. These engines will generally start OK down to around 20 deg F. Any lower and you probably need a starting aid like plug up the bock heater, add an intake heater if it doesn't have one, or use a little starting fluid. Don't overdo that last one. One small squirt should be enough to fire it.
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