At the end of my patience-1984 300D issue - PeachParts Mercedes-Benz Forum

ytr1903 · #1 03-04-2013, 07:02 AM

Hi all,

My son is still driving his 1984 300D, or at least he was until a week or so ago.
Here is the situation. He doesn't drive it that much, maybe twice a week and even then doesn't drive it very far. In any case, a couple of weeks ago he went to start it and the battery was dead. He took it to get checked and found that it was a goner. It was about 8 years old or so. He installed the new battery, the car started right up, but had no power. He can sit in the driver's seat in neutral and floor it, the engine will only rev to around 2200 rpm. He called me for some of my sage, fatherly advice, so the first thing I told him was to change the primary and secondary fuel filters. He did that, tested it and no difference. I told him to check the Alda connection for blockage, he did that, no difference. Alda line was open. I live about 50 miles from him, so it is difficult to get really involved with the problem, but yesterday we were near his house so I we stopped in. I had him start it, while I cracked each injector open. Each time the engine would falter, as if that particular injector was performing correctly. I then did a diesel purge, (thereby, eliminating the tank strainer, and cleaning up the system at the same time). No difference. It idles just fine, but when revved, it puts out way too much black smoke. I have run out of ideas. Help!!

Tom

cho · #2 03-04-2013, 07:12 AM

.

is the throttle linkage free moving all the way to the stop button on IP?

black smoke (unburned fuel) might be lack of air issue...air filter new?

alda settings have no effect on idle IMHO.....

edit; strike the alda opinion...what about EGR..disconnected?...he is not frequent driver so it
may be plagued,...nice italian might do the trick

cheers
.

ytr1903 · #3 03-04-2013, 07:18 AM

Thanks for the quick reply. I failed to mention that the air filter was pulled off for the test. Yes, the throttle linkage is working perfectly.

Tom

vstech · #4 03-04-2013, 07:24 AM

Hmm... no revs past 2200 rpm... any chance the car hit a dip? oil level? valves adjusted? seized a/c compressor? alternator?

JimFreeh · #5 03-04-2013, 07:45 AM

Blocked exhaust?

Jim

ytr1903 · #6 03-04-2013, 08:07 AM

Jim,

The exhaust has to be open, the engine is throwing massive amounts of smoke out of the tailpipe as it is revved.

Vstech,

The oil level is right on, the a/c compressor has not been attached for years. The alternator may be frozen but I doubt it. I don't remember the charge light coming on during all of this, nor did I hear any squeeling or smell any rubber burning. I will have him check the alternator real quick, though. What would hitting a dip have to do with the way it is running? I will have him check that also, if you give me a direction.

Tom

ytr1903 · #7 03-04-2013, 08:08 AM

The Don,

I bypassed the strainer and fuel cap when I did the purge. No difference.

Tom

barry12345 · #8 03-04-2013, 08:23 AM

Quote:

Originally Posted by ytr1903

Jim,

The exhaust has to be open, the engine is throwing massive amounts of smoke out of the tailpipe as it is revved.

Vstech,

The oil level is right on, the a/c compressor has not been attached for years. The alternator may be frozen but I doubt it. I don't remember the charge light coming on during all of this drama, nor did I hear any squeeling or smell any rubber burning. I will have him check the alternator real quick, though. What would hitting a dip have to do with the way it is running? I will have him check that also, if you give me a direction.

Tom

Hitting a dip is a refferance to another current post. A guy apparently hit a dip and has been unable to get the revs up past 1800 since the episode it appears. I was not sure if the comment was tounge in cheek or not.

cho · #9 03-04-2013, 08:36 AM

.

what about long overdue + winter on valve adjustment ?

.

vstech · #10 03-04-2013, 08:40 AM

Quote:

Originally Posted by ytr1903

Jim,

The exhaust has to be open, the engine is throwing massive amounts of smoke out of the tailpipe as it is revved.

Vstech,

The oil level is right on, the a/c compressor has not been attached for years. The alternator may be frozen but I doubt it. I don't remember the charge light coming on during all of this drama, nor did I hear any squeeling or smell any rubber burning. I will have him check the alternator real quick, though. What would hitting a dip have to do with the way it is running? I will have him check that also, if you give me a direction.

Tom

Brace yourself for a big read... similar problems with the car running only to a certain RPM...
Little or NO power after bottoming out suspension- 1981 300SD

ytr1903 · #11 03-04-2013, 08:49 AM

cho,

Although I have not actually checked the valve adjustment for this issue, my records show that we adjusted the valves less than 4000 miles ago.

vstech,

I will read the thread that you referenced.

Tom

JimFreeh · #12 03-05-2013, 07:21 AM

Quote:

Originally Posted by ytr1903

Jim,

The exhaust has to be open, the engine is throwing massive amounts of smoke out of the tailpipe as it is revved.

Tom

Not necessarily, my 87 300TD had massive amounts of black smoke when the oxidation catylist plugged up. I dropped the exhaust just behind the turbo, and found the lost power. I subsequently broke out and removed the matrix from the OC, just leaving the hollow shell.

Jim

TheDon · #13 03-04-2013, 08:02 AM

blocked fuel tank strainer, blocked tank vent?

daw_two · #14 03-04-2013, 08:12 AM

All good options and I'm just glad this has never happen to me. But then again, I'm a big believer in treating my tank of any newly acquired diesel with some biocide.

I've never had a clogged fuel tank strainer --- there have been some very gross pics shared on this forum in the past.

cho · #15 03-04-2013, 08:22 AM

Quote:

Originally Posted by TheDon

blocked fuel tank strainer, blocked tank vent?

my thoughts at first,but he stated diesel purge and same error,so it leaves
maybe overflow valve...maybe ...but he has loads of black smoke...mmmm?

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