Hello new forum lurker here with a couple issues that I hope you can help me with. I have searched the web and found some help in diagnosing these issues but I want to be sure.

I have a 1989 e350 7.3 idi diesel van pickup conversion. It has new batteries and glow plugs. Over the weekend I was running to lowes for remodel materials and I was having a incredibly hard time starting. It had a real slow crank and wouldnt start. So I went and bought two new batteries. Then it took a lot of slow cranking to finally get it started. Then I when highway driving it was really a dog. No throttle response except at the low rpms and I could barely get it above 55 mph. The gas mileage went to crap also. I know its no gas sipper normally but I have hauled things in the past and it has had guts on the top end and got reasonable gas mileage.
I am thinking I need to replace fuel lines and injectors. It seems to be missing when driving highway speeds. Today I made sure the battery cables are clean and they are. Batteries are new so no problem there. But when I went to start it was an incredibly slow crank then it screeched once or twice then stopped trying to turn over altogether.

Am I looking at a new starter motor and solenoid? Along with fuel lines and injectors?

When running down the highway my father in law who was driving behind me mentioned it smelled like unburnt diesel fuel. The truck had white smoke coming out the exhaust when I initially got it going but it goes away pretty quickly. I figured that is the nature of the beast.

Any help would be appreciated. I have scoured the threads trying to find a solution to diagnosing my issues but I finally came here because it seems I can find a more personalized response to the problems at hand. Thanks.

 

welcome to FTE.
the starting issue sounds like a bad starter.
here are two short videos. the first one is of a bad starter at 70 degrees
the second is with a new starter at 40 degrees.
click on the picture to play the video.
old bad starter:

new good starter:

 

as for the lack of power, i would start with an air filter and fuel filter if you do not know the age of them.

when you change the fuel filter, fill the new one up with clean fuel, diesel kleen, or the like to help purge the air from it. another trick is to fill the fuel filter with diesel kleen and start the engine. let it idle for 30 seconds then shut it off and let it sit overnite. this will help clean the injector pump. and toss a quart of ATF in the fuel tank for the next 2-3 tanks befor you start changing injectors. they may just be sticking a bit. the ATF will help clean the nozzles.

 

More info would help, how many miles on the engine, is it auto trans, what does the engine oil look like, and do you know the actual oil press? I'm no expert, I'd first see how easy it is to turn the engine over by hand, if it's easy (normal), it could be multiple issues, starter, injectors, fuel pump. If you can't turn it over, you probably have major issues. Either way, I would take it to a REPUTABLE diesel mechanic to have it diagnosed. It will be cheaper to find what the problem is, than to just start throwing parts at it.
Good luck!

 

No telling how many miles it has on it. It shows 059xx miles. I have changed the oil and it is quite black which bothers me. It is an auto transmission.

I havent tried to hand crank it just yet. I am afraid that I might be nearing the end of this engine. If I did try to hand crank and it was difficult I assume were talking serious issues.

I havent had this vehicle long. I bought it for the semi sleeper and flatbed setup that I could haul my backhoe and trailers. Luckily got a deal on it.

In that case I might be better off swapping to a ford 460 gasser in the future.

 

mileage is not an issue if it was properly maintained. my 88 has 494,000 miles on it, and still runs like new.
and i can not turn it over by hand. these things have 21:1 compression ratio.
i would say if you can turn it over by hand you have serious problems, not the other way around.

 

Right.hard to hand crank equals good compression ... the proper compression I believe is there. And the oil will naturally be dark from some residual oil that is left when changing oils.

Im thinking starter and injectors would be the first culprit to check out. It wont even try to crank anymore. And the batteries are good.

 

look closely at the ground connection on the block, and the positive battery cable.
if the coating on the cables are cracked, look inside at the copper wire itself. it could be severely corroded. corroded cables equal no or very little power passing through. but i doubt that is your problem, i really think the starter is toast.
and you are correct on the dirty oil. i can change mine, and 5 minutes later the fresh new oil is black as the frame paint.