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Robert, RV Mechanic
Category: RV
Satisfied Customers: 13518
Experience:  18 yrs. RV experience including Cummins North West, Country Coach, Monaco Coach - vendor certified.
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Motor home..diesel..The fuel tank was almost empty, so I put 40 gal

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I just bought a 1982 Foretravel motorhome (diesel) that a lady had lived in for 2 years. I don't know how much it had been moved. The fuel tank was almost empty, so I put 40 gal in, and started to drive it home. I went about 35 miles, and it started to lug down off and on for another 20 miles, and then it gradually lost power altogether. I put 2 bottles of diesel heet in the fuel tank, but it didn't help. Eventually I was driving maybe 2 miles an hour, and it felt like it was moving on idle. Can you tell me what the problem might be? Thank you.

Hi There!!!


Thanks for Choosing Just Answer..


Do you know what kind of engine it is? Cat, Cummins? Also when this was occurring did any dash warning lights come on?


Thanks, Robert

Customer: replied 8 years ago.
From what I could find out it's a caterpillar engine. No, no warning lights. It just gradually lost power.



Yeah if it's Yellow engine it's a cat. The first thing I would do is change the fuel filters. This would cause the issue if they were plugged up, it has been sitting so this very well could be the issue. Next inspect all the fluid levels, low coolant or oil would cause the engine to go into limp mode, meaning the engine is going to perform poorly. Next I would inspect the turbo and Charge air Cooler. Make sure the Charge Air Cooler is not plugged with leaves and debris. You can also inspect the piping for the Charge Air Cooler, there should be some rubber boots with clamps on the piping going to the cooler. make sure they are not ripped or did not come off. IF one came off you would loose boost and the RV would loose power. I would suggest if you get it running to get it to a shop that deals with the RV application and have a chassis inspection done.. Also make sure no belts have come off. Another concern is if the unit sat for a long time some small rodents could have made nests or a home in the RV, I have seen this before so when you are inspecting everything look for any chewed wires etc. I would first start with the fuel filters..

IF you have any other questions or concerns please feel free to contact me!!!


Thank You!!! Please hit ACCEPT for my efforts, Positive feedback and BONUS welcomed!!!

Customer: replied 8 years ago.

We got the fuel filter off and flushed it out with diesel, checked the wiring, checked the fluids, and now we can't get it to start. I found out that it's a Detroit 8.2 remanufactured engine. I've heard that temperature makes a big difference with diesel, and the temp here has been running 25 or so at night and 30 to 35 during the day. Would that be a factor? Can you tell me if this might have an electric fuel pump and where it would be located? When we try to start it, it turns over and fires, but won't keep going.

Thank you for your help.

Hi Again,


I was hoping this was a Cat or Cummins engine. I have limited experience on the Detroit engines, they have become a rare breed in the RV's over the years. I am going to opt out hoping another expert has some information on this engine. You are correct most diesels have a block heater you plug in for cold starting. IF I do find out anything I will contact you, IF not I do not know when another expert will be able to assist you.


Thanks, Robert

Customer: replied 8 years ago.

Hi, Robert. Thank you for everything so far. I don't know if you'll get my response if I click accept, so I'll click reply now and accept later. I just wanted to be sure you know I appreciate your help. We'll work on it again today and hope we can get it home.

Thank you. Shirley



Thank you for appreciating my effort. One thing I have noticed is that you have flushed the fuel filter, I would really try to get a new one. Also when you put it on it is very important that it is filled to the top, if it is not filled you can get an air pocket and the coach would be very difficult to start.. Also if you had an electric fuel pump when you turn the key on you would hear it energize. Something this old might have a fuel cut out solenoid, when you turn the key this solenoid is energized pulling a plunger up. When the coach starts another coil in the solenoid energizes and it should remain up. Also this may have a manual prime pump for the fuel system, these are very difficult to operate and it takes allot of pumps to bleed the air out.... I hope this information is a little helpful, I actually talked to another expert about getting a print for you on Monday...


Thank You!! Please hit ACCEPT for my efforts, Positive feedback and BONUS welcomed!!

Robert and other RV Specialists are ready to help you
Customer: replied 8 years ago.

Hi. We tried to get a new fuel filter Friday, but we live in a very small town, and they didn't have one in stock. That's why we tried to flush the old one. We can order one tomorrow. In the meantime, I guess we'll probably have to have it towed up here where we work on it easier. Right now it's about 15 miles from here parked in someone's driveway. I'm looking forward to seeing what you're talking about on Monday.

Thank you. Shirley