Car idles rough then dies ('83 240D) - Page 3 - PeachParts Mercedes-Benz Forum

barry12345 · #31 09-24-2014, 06:06 PM

If the engine was acting well just prior to your relatively fairly short period of storing the car. My guess is that all of a sudden the engine is not worn out. Especially so if it was running great and started up very fast with little cranking required in cooler weather.

Now something new mechanically happening is also a possibility but not that likely. What exactly is the mechanic basing his decision on? The quick discoloration noticed of the primary filter you mentioned on replacement to me sounds like like junk in the tank is processing.

cooljjay · #32 09-25-2014, 01:43 AM

WOW the engine is shot...

That is code talk for, I don't know what is wrong and I don't feel like finding out what is wrong....so smash it and buy a new one...

Can't wait to hear his proof to back this up...

cho · #33 09-25-2014, 05:57 AM

.

try to idle/run from separate can/bottle of diesel
just override tank and lines,prime the lift pump
and cranck... similar to procedure of dieselpurge
but with diesel only in can/bottle

the results will lead your actions easily after....

you will be sure what side of car to examine/repair after....

cheers

ChO

.

vstech · #34 09-25-2014, 06:49 AM

I agree.
If he is not showing you compression numbers below 200 on all cylinders or one cylinder more than 25% lower than the others I would ignore his evaluation.

Start with a bottle of fuel sitting in the engine compartment. Dieselgiant. Com diesel purge tutorial. ..

vstech · #35 09-25-2014, 06:50 AM

Valve adjustment can cause this also...

Yumeko-chan · #36 09-25-2014, 11:57 AM

Went and got my car this morning. Told me compression was below 350 on all cylinders but would not give me specific numbers.

barry12345 · #37 09-25-2014, 02:45 PM

Quote:

Originally Posted by Yumeko-chan

Went and got my car this morning. Told me compression was below 350 on all cylinders but would not give me specific numbers.

Even if he is telling the truth below three fifty is still very well workable. As long as it is not down around two hundred. Get the bottle of clean diesel fuel set up in place as a test. Also if you have not adjusted the valve clearances in a long time and it is unlikely this mechanic did. This if not done can negatively tweak a compression test to some degree. Right now you can pass this step if the engine ran well just before the car was stored. .

Once again other than the rings maybe sticking a little from storage and a year is not really that long. If it was running well previously before storage it can do so again. This is incidentally almost a certainty.

I would not bet much on two of the four diesel Mercedes 123 engines I have would make 350 pounds pressure on a compression test. Yet they run very well with adequate power. True lower compression engines are usually very, hard to start as the temperature gets below say 40-45 degrees.

If the engine was not consuming a lot of oil before is another good sign in general. On the 616 four cylinder cars I figure that getting more than a thousand miles on a quart of oil consumption with no obvious engine oil leaks to defeat the test.. The engine is still probably okay. Certainly still useable normally.

At todays highway speeds the four cylinder 616 seems to burn a little more oil as the revs are higher than the five cylinder engines experience. Perhaps some 616 engines do not have this trait but my two examples do. One to a greater extent than the other and one 616 engine is a pretty much very low milage factory rebuilt.

My message is basically just do not give up yet. I see no issue of it being a dead end so far. Plus several members are singing pretty much exactly same tune from personal experience. A couple of them have far more experience than myself as well. So they are not to be ignored in my opinion.

Look I purchased a decent looking 123 diesel road kill car from a foreign car specialist. That in my definition is a car that broke down on the road. He told the customer after a flatbed tow in the injection pump and starter where finished.

Actually it was just the strap or wire burnt off from the starter solenoid to the starter and the tank vent was just obstructed. The mechanic actually believed what he told the customer.

He seemed a little upset I was told when he heard I had the car up and running well in about an hours time for less than two dollars in parts.

In his case I think he was an honest mechanic basically and the symptoms just fooled him. The car was just placed on vegetable oil and besides it being very cold. He had just finished changing a few injection pumps out as the local biodiesel was destroying them.

It was so bad an epidemic the local biodiesel fuel was removed from the marketplace. My own guess is most if not all those injection pumps that got changed out where just gummed up and might have been cleanable.

Back then the common knowledge of injection pumps even by working mechanics may have been far less than has evolved on this site over the interm period . Especially since the time I purchased that car. Incidentally I am not trying to mislead you.

You want a bottle of fresh diesel fuel with the pickup from the lift pump input hose installed. As others have suggested. Plus a line from the return of the injection pump installed to the bottle as well. You can eliminate doing the return to the bottle initially if the engine fires right up. Look up the procedure on the injection pump cleaning flush.

That return line would allow you to also watch for any air in the return line coming out with the surplus fuel. Plus some test verification the lift pump is working well.

When you start to do this if you do let us know. There are some minor additions in the test that will be required if the engine does not just fire up well. You have a better than fifty percent chance it will.

The clue Is you saw a new primary filter get dirty internally right after installation. This is not normal. This can indicate a probable partial obstruction in the fuel supply. Or a lot of garbage in the lift pump and supply system.

You have been typically describing fuel starvation or a lot of air getting in the system right along. It is what one could call a fairly common issue with these cars. The beauty is usually it is very cheap to self rectify. Perhaps you have an aquaintence or friend with some car repair knowledge to assist you? They usually are happy to help if asked. This is not that complex.

vstech · #38 09-25-2014, 02:52 PM

cold compression will ALWAYS be below 350... 250 is even fine... the problem is if ONE cylinder is 25% lower than others...

specifics are important, but if the valves were not adjusted for the test, the numbers are useless....

take it home, and lets work out what's wrong with it.

Yumeko-chan · #39 09-25-2014, 04:30 PM

I've never had the car stored. This is my daily car, and I've been having to drive it a lot more since the job I got in April is across town from me (15-20 minute drive).

Aside from what I mentioned in the beginning, there was something else going on that I figured was unrelated: the car has been going through a quart of oil every other week. Very unusual, and even more unusual, no puddle under the car to suggest any type of leak. Also, a few other things started happening since my last post in July: the car started to get a little more difficult to start in the morning (and no, it's not that cold here yet), and upon backing it out of its parking spot, it would die, every time. Rinse and repeat several times until I'm backed out enough to go forward and get along on my way. Once at speed the car is perfectly fine.

As I think I mentioned before, the oil cap started leaking, but it's gotten worse. Not leaking a whole lot, but still.

Vacuum issue appeared, where the engine won't stop running even after I turn off the ignition. I have to press the STOP button on the engine to kill it. Shortly thereafter, the lock on the front driver's-side door stopped working, so I can't lock that door anymore.

Also recently: my car's never been a big smoker, but now I am definitely getting blue smoke. More upon startup than there is once the car's warmed-up.

Oh yes, and blowby. Plenty of blowby. Engine still shakes too.

Car's never been run on veggie oil or biodiesel, only regular diesel.

I asked Salim like five times to give me numbers other than "lower than 350," but he would not/could not give them to me. I got the call about the engine being "shot" about four hours after I dropped off the car with him, so I'm not sure if the compression test was done hot or cold. Asked him if he could name anything else going on with the car, but he just kept repeating the stuff about the low numbers and how it wasn't worth fixing.

barry12345 · #40 09-25-2014, 04:42 PM

My errors on prior postings on your thread.. I thought this was a car coming out of storage. Some confusion of the basis of reading other peoples threads on my part was unfortunate. I am sorry about that. I just re read your whole thread.

If you loosen the oil filler cap when the engine is running what is happening? If you rest the cap on the hole will it stay there when not screwed down at idle?

The sudden appearance of oil present at the closed cap you mentioned very early started me wondering about high base engine pressure developing. Or perhaps an obstructed crankcase breather hose even causing it.

Either could be an issue.. How many miles a quart of oil has the engine been getting if any ideal? The car could have other than fuel issues is not an impossibility.

Excess crankcase pressure present in the engine can create a situation where the injection pump tries to shut down. Or partially shut down. Or can actually shut it down. . This last suggestion about excess base engine pressure only takes a minute to check out. If you post what the oil cap does might help with the engine at warm idle.

If it does other than just basically sit there or jiggle when loose it may be important. If it wants to launch into orbit I hope it is just an obstructed sludged up crankcase breather hose. If not it may be really serious. If you can figure out a way to contain the mess. Starting up the car and trying it with the oil cap off would be a pretty conclusive test if it returned to normal. I would remove and clean the crankcase breather hose or at least check it out before that though. Oil cap off could be really messy yet a very conclusive test.

I do not think we as members have examined the issue on site of what if any oil consumption is increased by increasingly high crankcase pressure in one of these engines. Oil in the engine will be driven towards anything at atmospheric pressure or less by it in a more aggressive fashion I suspect. So things like the condition of the valve seal rubbers become more important.

leathermang · #41 09-25-2014, 04:53 PM

Quote:

Originally Posted by Yumeko-chan

........ smoke. More upon startup than there is once the car's warmed-up.......

I asked Salim like five times to give me numbers other than "lower than 350," but he would not/could not give them to me.......

More smoke at start up is classic worn ' valve stem seal ' ...
cheap parts... but some labor....
I also recommend replacing the valve rotators and the springs while you have it opened up that far... those parts are cheap... at the heart of the engine working correctly....and are no extra labor ... just put in instead of the old ones...

Yumeko-chan · #42 09-25-2014, 05:07 PM

The issue with the oil at the cap appeared at the same time as the original issue that prompted me to start this thread. I don't think that's entirely coincidental.

barry12345 · #43 09-25-2014, 06:04 PM

Quote:

Originally Posted by Yumeko-chan

The issue with the oil at the cap appeared at the same time as the original issue that prompted me to start this thread. I don't think that's entirely coincidental.

Nor did I but I got lost in thinking it was just another car out of a year or mores storage episode.. Fuel supply issues are almost endemic with those cars.

Just not as signifigant then with an older engine that had been in storage . It would have in all probability stopped weeping soon after going back into service. . Now it may be important unfortunately.

I can only hope that breather hose is partially obstructed. Otherwise things may not be good. A lot is riding on the oil filler cap test. Or the breather hose obstruction. Sometimes I like or actually preffer being wrong.

There is hope in that direction as usually high crankcase pressure situations are more prevalent at higher rpms than you seem to be having issues with. Normally the higher base pressure would make the key shutoff function better not worse is another one. Excess pressure inside the engine acts to turn the injection pump off.

I have always wondered if this was a purpose designed safety feature or just an unintentional result or byproduct of design. If you are in a position where you are strapped for a car. If the crankcase pressure turned out to be a culprit. If the breather hose is clear. I may be able to suggest a way to increase the breathing ability. This would still just be to prolong the innevatable perhaps. Oddly enough I might even expect the oil consumption to drop somewhat though.

cooljjay · #44 09-26-2014, 10:23 PM

This sounds like the typical non maintained diesel. It sounds like a lot of things need to be done, and daily driving a car shows you how much it needs to be done. I see a lot of problems that are very normal on these cars that needs to be addressed. It sounds like you are not able to do any of the stuff your self, and then no other shop will want to do it.....hints to why they say you need a new engine, they no for a fact you want cough up the change....and then we see it at the junk yard or on CL for cheap...

Yumeko-chan · #45 09-27-2014, 08:05 AM

I filmed it yesterday to give you guys a better idea of things.

https://www.youtube.com/watch?v=HkIPNAWVy3I&feature=youtu.be