Since I had only driven the car around town, and never more than 20 miles or so at a time since I owned the car (it is just a "beater with a heater"), he changed them on the road because they got clogged from running so much fuel through the system. I checked today, and the fuel in the pre-filter looks fine. The new style primer pump works good as well.



I pulled the glow plugs today and did a compression check. The results:


(1) 250
(2) 240
(3) 320
(4) 100


I now know what the problem is. I even did #4 over again, and it still only got up to 100. I could see a mist of fuel coming out of the other glow plug holes when cranking, so I know it is getting fuel.
I got my pump oiler, and pumped about a pint of MMO in each cylinder. I will probably do another round tomorrow, and may even pump a bunch in #4 before putting in the glow plug and soon after trying to start it. If all else fails, I will sell it as-is or part it out.......Rich

my first line of thinking would be to hook up some fresh fuel with fresh filters in a bottle and try and run it off that after priming the system. That way you can easily trouble shoot the fuel tank, fuel IN the tank, and any of the lines.

EDIT never mind, just read your response! sorry to hear that ;(

Yea, since I saw fuel mist exiting the other three cylinders, I pretty much knew it does not have a fuel problem.

that’s awful. I hate it when people do this to me. My wife borrows my 300sd and it always comes back with something broken. I love her but that is pushing it! :D

For what it’s worth, I drove my 240D with over 300k for 2 years on used motor oil from my wife’s Honda. I knew the car was going to get donated so I figured heck, just top it off with old oil. One quart a week. It leaked but had great compression. Long story but I had to dump the aging car due to a move to the hill country and too many worn parts. But that engine just took it. It started and ran well till they drove it away. Shame.

Not an oil problem if it was not knocking since it ran after being returned.

This is a fuel delivery / starvation issue. Unless it is locking up and barely turns, the entire engine won't suddenly suffer all injectors failing or all piston rings failing or all intake / exhaust valves not sealing.

My 70's International backhoe ( with a German built Neuss engine ) was run at 1/4 or lower tank before I bought it and for a while I did the same. For a big job I filled it full. Soon after ( like at 1/4 tank ) It started clogging fuel filters that were a few hours old ( RE when I was running at 1/4 tank ).\

With a full tank, sludge was washed off the area above 1/4 tank. I'm betting that you usually ran the car with less that a full tank and the recent guy filled up.

So the engine is running now?

Do a leak down test before going any farther, we need to see where the compression leak is.

What was the compression in the past? It is sounding that the engine was pretty worn out before your guy used it.

I do have a leak down tester, so yes, that is next. I have never checked the compression before today. It usually started without issue in the three seasons other than winter. It did start in winter using the block heater and glowing at least two cycles.

Just sounds like a tired engine to me. If a diesel has a hard time starting in cold it has poor compression or bad glow plugs. The trip and hauling the trailer might have accelerated the wear even more.

The more I think about it, I tend to agree with you. However, why would one cylinder be so much lower than the rest?

Perform the leak down test - you don't know if it is a top end or bottom end issue yet. There are a lot of possible reasons for poor compression - a single bent valve would only affect one cylinder, for example.

Sometimes some cylinders wear more than others. I’ve seen some cylinders fail completely or have significantly lower compression than the rest.

Here is an example of an engine that allegedly had 300+ psi on cylinders 2-5 and 0 psi on cylinder 1.

https://i.imgur.com/fxUqndD.jpg

I'm with Jake12 on this. Performing the leak down test is a waste of time. If only one or two adjacent cylinders were low then it would be useful. All four low? Fuggedaboudit! Source another engine and move on.

A leak down test doesn't take very long. Diagnose, don't guess.

Reminds me of when I loaned a nice (almost NEW) 2stroke leaf blower to a neighbor (along with some gas). He ran it all afternoon, used up the fuel we provided, then ran a full tank (or two) of gas with no oil mix through it. Engine was toast. Hands it back saying "it stopped running".

:glare:

It was then I essentially swore off loaning people most things...especially cars or power tools. (I do make a few exceptions for specific friends or family who treat tools/things nicely)