Well I did it. I bought a 2001 Dodge Dakota extended cab with a 617 Mercedes turbo diesel. Here's the risky part, it wouldn't start when I bought it. PO said the injection pump was out and that was it. Included in the price was a working used one. The conversion looked like it was quite well done so it didn't take me long to buy and have it on a tow truck.

Got to my mechanics shop and the new IP was put in, nothing... Ugh the new (used) pump was a dud. I bought a rebuilt one and we got it in yesterday and the truck came to life! Engine sounds great when it runs. Was blowing heck of a smoke though, I'm sure that will go away it had been sitting for months.

Now the problem. Once it get's warm it doesn't want to start again. And when it's running it gets too hot and shuts off. We figured out the electric fan (no mechanical one there) wasn't working. So I have ordered a thermostat wiring control for the fan. We did jump the fan but still couldn't get the engine running again until long time and it was cool

I'm going to replace the glow plug controller with the updated one as there was something wrong with the old one and we had the jump the plugs too. Anyone have any ideas on why the engine runs great but won't start when really hot?

Also, any ideas on the fuel pump. Because there is a working one in the original dodge tank, but it's not hooked up to run. We jumped it to get the fuel flowing and the MB mechanical pump seemed to work thereafter. Does that sound right?

I'm going to replace all the rubber fuel lines next in case there is air leaking in when warm... Thanks for any help! The truck is at my mechanics shop, when it's fixed I'll get pics taken and upload!

 

Why did the PO sell it? How many miles on the conversion? was it running WVO, or some such? If a benz won't run check for fuel issues air leaks or fuel restriction. From what you described, I would start with the fuel filter. Then some folks have had aerated fuel enter the system from the return line causing air bubbles in the fuel tank, but most likely you are getting air in there somewhere
I think most people don't run the in tank fuel pump, and you can check for restrictions from the tank fuel pump still being in line.

 

The story was his friend did the conversion, owned 12 cars, when he finished it he decided he didn't want it anymore and wanted another project. His friend got it from him for a deal. He drove it daily for several months (about 5,000 miles) and then the injector gave out. He said he never ran WVO or WMO through the engine...

I think you are right with fuel restriction and or air leaking in. I have all new fuel lines coming in.

We hooked up a new line to the gas tank and were blowing and sucking on it, nothing... We got that problem fixed by jumping the in tank pump. My question is does the in tank pump only allow one way flow? or do we likely have an issue in the tank? Should we drop and drain the tank?

 

My mechanic just called and he thinks we need to ditch the in tank pump setup and create a new outlet for the fuel to flow at the bottom of the tank. Dakota draws from the top of tank unlike Mercedes which draws from the bottom. Does this sound like a good plan to you guys? I'll report back more later...

 

have you read the numerous MB conversion threads. and looked at Peachparts forum, and superturbodiesel? All the issues you are going through have been discussed on quite a few other threads.
The intank fuel pump has been discussed a lot. several threads have pictures of the mods. most folks have bypassed the intank pump, and re-engineered the fuel system to accept some sort of fuel return, that eliminates aerated fuel from coming back into the tank

 

dieselxj is correct, you can check out what I did about the fuel pickup and return on my build. I would also suspect the rebuilt pump and the pump timing. The pump can be timed incorrectly and still run the engine with symptoms similar to what you are describing.

 

Thank you dieselxj and Evenglass! Evenglass I looked at your XJ and that is awesome! I have an 01 XJ and an 86MJ. The MJ I was actually going to do the 617 conversion myself, but then I stumbled into this Dakota.

Great advice. Here's my question, wouldn't it just be easier for me to add a fuel outlet port on the bottom of the stock Dakota gas tank? That way it would be exactly how the MB tank was. I'm not quite sure how to do that though, any ideas? I'm trying to find a bolt on fuel tank out/in that can be mounted on the bottom of the tank just like MB.

 

ok it is time for some pictures of your truck. I have a ext cab Dakota, and I would think that the MB would be a pretty tight fit in the Dakota.
Why would you want to molest a perfectly good fuel tank by putting a whole in the bottom? You might not even have to drop the tank to pull the submersible pump for the mods. just my opinion, for me it would be much much easier to work with the pump/sending unit while out of the tank, than it would be to try and drill install and SEAL a fitting into the bottom of the tank.
PLUS most fuel systems don't pull fuel from the very bottom of the tank, there is usually some sort of a stand off from the bottom. The bottom of the fuel tank is where the water and all the stuff you don't want in your engine collects

 

I will take pics as soon as possible, it's still at the mechanic's shop. I should be able to get some up on Monday when I go back there.

Well I don't want to mess with that fuel tank it's just that it seemed to me gravity fed the way the original 617 was setup is the best way to go. Instead of sucking up and over the fuel flows just down.

I've had my 300TD for 10 years and put 150k on it, never one issue while on the road. I change my fuel filters every once in a while, but never had an issue with that gravity fed fuel system.

 

Thank you. Hope you get the issues worked out soon. Keep us posted.