81 300TD All of a Sudden Won't Run Right - Page 2 - PeachParts Mercedes-Benz Forum

tfrain · #16 02-15-2007, 06:27 AM

by the way, these pictures are from when I purchased it. That isn't my for sale sign or anything in it and the carpets were dirty. It was back in the summer (hence all the green in the trees/grass). The pictures show the condition of the body. It isn't too bad. The drivers side rear quarter has some bondo in it, but obviously not a lot or the dent in it now (that was done after the prior repair) would have crackled and crumbled all out. it is a very solid car, and like I said I love the utility. I can ge sooo much stuff in the back with the seats folded down and it gets great mileage and cruises so smooth, stops very well with the 4 wheel disk brakes. Love it. Problem is I am inheriting my wife's civic and I can't get rid of that car. She has had it since new and I know it has been well maintained, so I just can't get rid of it because I wouldn't get what it is worth, so I'm selling this one. I paid $1500 for it back in the summer and will take the loss on it, unless of course I can get it fixed, then I'll probably want maybe $1300.

Anyway, I would still like to fix it. I enjoy wrenching!

Thanks,
Tom

vstech · #17 02-15-2007, 08:32 AM

I will be following this, as my 83TD is exibiting similar behavior, I hope you get it running smooth again.
John

tfrain · #18 02-17-2007, 07:18 AM

Today is Saturday, GLORIOUS SATURDAY, so I am going to take a look at the wagon. My concern now, however, is that it might be severe engine damage instead of just a fuel issue.

If I had severe damage (say a melted piston or something broken) I'm guessing the engine wouldn't run, right? I'm concerned because the ALDA was bypassed when I bought it and I haven't had a chance to correct that yet.

Before this happened, the engine ran fine with very little smoke and had what I consider pretty good power for a tired diesel engine. The motor has 380K miles on it, but because of the little bit of smoke, I figured it surely had a rebuild on it. Not to mention the engine was so clean, the interior in such good shape, etc, that I figured it had been at least decently maintained.

Any opinions on whether it could be shot? It will run, just really poorly like it is going to die at any minute and smokes really bad. It drove itself into the garage and I plan on moving to the backyard to work on it and hope it will make it back there by itself.

thanks,
Tom

barry123400 · #19 02-17-2007, 02:27 PM

Nothing you have described up to this point has to be a terminal situation. In fact it probably is nothing too bad. Anyways any conclusion has to wait until you find whatever it is.

tfrain · #20 03-07-2007, 04:26 PM

I cracked open the injectors and found out it is the #2 injector/cylinder causing the problem (if going from the front of the car, the 2nd one back) - cracking the line at the injector on any of the other cylinders caused it to die, cracking the 2nd injector line didn't cause any difference in the way it ran... which tells me there is something up with this injector. I'm going to pull it out today and see if I can clean it out perhaps.

It is blowing some greyish/whitish smoke which I assume is because the injector is probably allowing fuel to get in, but it is probably dripping in the cylinder, not atomizing and causing a rich burn.

Please let me know:
1. If my troubleshooting assumptions are correct so far
2. What do to now - should I just buy a new injector?

Also, I tried running from a 2 gal container of diesel beforehand to make sure it wasn't a clogged strainer in the tank before I started this. I still haven't run and diesel purge through the car.

Thanks much!!!

Tom

tfrain · #21 03-07-2007, 04:27 PM

oh yeah, what size socket do I need? I'm guessing 30MM deep well - will that fit over the injector return nozzles??

vstech · #22 03-07-2007, 04:50 PM

27mm or 1-1/16 deep socket will remove the injector
swap it to one of the good cylinders to verify it's the injector, not the prechamber, or piston/valves... John

tfrain · #23 03-07-2007, 05:30 PM

I think I grabbed an 1 1/8 from a buddy - i'll see if he has a 1 1/16 deep well - that is what I guessed as well but we couldn't find it!!

Thanks for the suggestion about putting it into another cylinder to make sure it is the injector. I sure hope it is. If it is the prechamber, don't they make a tool for removing it? I've heard something about the prechamber ball - this is a high mileage engine.

barry123400 · #24 03-07-2007, 07:38 PM

If it's not the injector the next step is to do a compression check on the #2 cylinder. Also do a check on the cylinder you remove the test injector from. That will indicate the probable condition of the rest of the engine a little.
If your compression is low can you inject some air in to determine if you have lost a valve or whatever? Needless to say I hope it is just a bad injector.

toomany MBZ · #25 03-07-2007, 11:40 PM

Quote:

Originally Posted by tfrain

That is a good suggestion. How would I do that without spraying diesel all over everything and would I disconnect the line at the injector or at the IP itself?

#2 is your problem, make SURE it's getting fuel, looking up prechamber tool, if necessary, unable to locate, sorry. Possible problem there, air leak, maybe something else. Pull injector, test. Star magazine suggests a leakdown test better at determining problems, a compression test will tell you it's too far gone. Keep smiling!

tfrain · #26 03-08-2007, 04:41 PM

Quote:

Originally Posted by toomany MBZ

#2 is your problem, make SURE it's getting fuel, looking up prechamber tool, if necessary, unable to locate, sorry. Possible problem there, air leak, maybe something else. Pull injector, test. Star magazine suggests a leakdown test better at determining problems, a compression test will tell you it's too far gone. Keep smiling!

Thanks to everyone- hoping to be able to do it this weekend - REALLY REALLY looking forward to the early daylight savings time.

bgkast · #27 03-08-2007, 04:53 PM

Mine was doing the same thing, missing on #2, roughly running, smoking. Check the valves. My exhaust valve had tightened up and was hanging open. Adjusting it back to spec fixed the problem (hopefully before I damaged the valve or seat).

Any rust on that wagon? $1000 is a steal.

tfrain · #28 03-08-2007, 05:05 PM

Quote:

Originally Posted by bgkast

Mine was doing the same thing, missing on #2, roughly running, smoking. Check the valves. My exhaust valve had tightened up and was hanging open. Adjusting it back to spec fixed the problem (hopefully before I damaged the valve or seat).

Any rust on that wagon? $1000 is a steal.

Thanks for the info - it might be that as well. I was just about to do a valve adj on it when this happened so who knows - I've never looked at the valves at all in the short time I have owned it.

The only rust on it is the left drivers rear fender where the damage is that I spoke about before. It is rusted along the edge of the wheel opening but is still very solid - all in all it is a good solid car with no rot whatsoever - it appears to be original paint as well except the repaired fender - there are touch up paint spots all over the hood and stuff- interior is great - even the glass is good. I really like it alot. Maybe I can get it fixed up this weekend.

tfrain · #29 03-13-2007, 03:17 PM

I removed the number 2 injector, took it apart and cleaned it all off in a bath of mineral spirits. I couldn't really find anything wrong with it - there wasn't any trash or anything in the injector that I could see, but it was dirty. I removed the injector pin and noticed there was some black gunk around the tip that I removed by spinning it between my fingernails (if that makes any sense) - there was a lot of dirt in the container holding the mineral spirits - anyway, put it all back together, put it back in the cylinder, started it and did an italian tune up on it and now it runs like it did before. I'm thinking of cleaning all the injectors in this manner to see if it will improve the whole engine - it is a little more rough running at idle when in gear than I like. I may change the rack bolt as well - the engine mounts look good. I didn't do a compression check as I didn't have the adapter and I needed to get it running.
I'm now thinking about fixing the few minor body problems and repainting the car and either keeping it or selling it for more than I could get for it in its current condition. The engine really seems to be in good shape to me and it is a solid car. Maybe I'll keep it and get rid of the civic instead!! I love my wagon ,just can't afford to have extra cars right now.
But of course, if anyone is interested in it let me know. I appreciate the help in getting this issue resolved.

vstech · #30 03-13-2007, 03:28 PM

you disassembled the actual injector? and removed the pintle pin? wow. I thought that was unwise. did you take any pictures?
John