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Comments
Should I start with changing the thermostat. I can imagine that it is a quick and cheap switch, or something else. Are there other things I can do to dignose the problem with my lovely old benz?
thank you so much for all your help. I appreciate your time and knowledge.
I am just looking to do stuff like valve adjustments, etc.
question 2: we are also getting a lot of oil leakage which is also going into the air filter. How do I know when that is something bad opposed to the typical 330d oil leakage?
- I also know we need to replace the vacuum hoses because we are having to turn off the car manually a lot and the door locks don't work correctly.
Thanks for any help!!
I have a 1982 300D turbo. Last 3-4 days, transmission is not shifting into higher gear as it used to. Starts fine, shifts into 2nd. but then engine rpm goes way up- 4500 to 5000 until speed of 45 mph, and then shifts with a jerk.
Checked transmission fluid level- it is ok.
The fuel filter has black stuff in it- I am going to change both filters tomorrow (haven't been changed in a while- slap on my hand!!).
Door locks don't work, so there is a vaccum problem somewhere- they haven't worked for 6-9 months now. Could this be a problem for shifting?
Any other suggestions? I am not driving the car now- afraid to damage the tranny.
Thanks.....
As for black stuff you may want to add a biocide to your tank---sounds like diesel algae is growing in there.
Black stuff- 2 weeks back I had the oil changed, and they added some stuff in the tank to clean up the lines and injectors- that may have "loosened" up some stuff. Do you recommend any biocide? Is it better to just add stuff in the tank, or do a diesel purge with the kit? Thanks again...
I am interested in purchasing a Mercedes, not for the usual reasons, but because they are the car of choice for biodiesel conversions. I have a contact who performs these conversions and sells the converted cars. They are also beautiful cars with good reputations as being made well. However, the parts are pricey.
He has a 1979 300SD with 260K (transmission has been replaced) that he is selling for 3400$. Each front seat has a small tear and the paint on the surface of the trunk has oxidized. Otherwise, the car looks good in the photos.
The thing is, he has to drive it up from LA for me to take a look at it and therefore would like me to commit to a purchase prior. I can understand his point of view, but am not eager to take this risk. Based on the posts in this forum, it would appear that I was correct in this reaction. I have learned a number of different things to look for during a test drive. I am not sure where else I could get a converted car, though, except from this guy and really think it would be so cool to run on free used veggie oil.
Thanks,
Z.
P.S. The other question I had was about the "turbo" feature. My boyfriend said under no circumstances to buy a "turbo" diesel because I would have nothing but problems with the turbo portion of the diesel.
If by "purge" you mean an injector cleaner...yeah, I've seen a good dose of injector cleaner + new filters + a valve adjustment totally revive ailing old Benz diesels.
RE: Modulator --- I don't think it requires adjustment, although the mechanical throttle linkage might but I wouldn't mess with that without careful study of the manuals....you can test the modulator if you had one of those vacuum test pumps that sucks on it and that way you can tell if it leaks. I suppose you could take it off and put a piece of hose on it and suck on it yourself, and then stick your tonque in the tube to see if your tongue sticks (this tells you it is holding vacuum). A disgusting kind of thing but hopefully when you suck there isn't some foul tasting debris in there. Well whatever doesn't kill you will make you stronger as we say.
So it's not so simple. You are saving money on fuel but you are putting in considerable labor.
If you want to just buy pump biodiesel (B100) you don't need to "convert" a normal Benz Diesel at all. Just change the filters after your first tank of biodiesel B100 runs through.
Of course B100 is quite expensive, even more than regular diesel fuel.
I wouldn't commit to buying any used car prior to driving it and having it checked out.
And I agree, a turbo diesel is a much better car than a regular 300D--- a 300D will freak you out on highway on-ramps. It was a car built for 1980 and things moved a lot slower.
Tell you what---get in a normal car, and from a stop, take exactly 21 seconds to get to 60 miles per hour. If you can live with that, you can live with a 300D non-turbo.
300Ds without a turbo are best in heavy urban situations. If you are going on the highway you should have a turbo model.
As for the "biodiesel" craze, I think you need a more sober view of what's involved in hauling, processing and using veggie oil as a fuel. It can be fun and I think it's a great idea, but it ain't easy.
I started the car, fired up fine and then stopped- probably because it used up the existing fuel in the system.
Now it won't start- probably because the filter is empty, and fuel cannot get to the injectors. In retrospect, I probably should have filled the main filter before screwing it on.
How much trouble am I in now? Have I sucked air into the engine? How can I fix this?
Can I just unscre the filter again, fill it with diesel and screw it back on?
Help!- thanks.
If you can't prime the injectors with this built-in pump, you have to have a friend crank the engine whle you just loosen NOT REMOVE each injection line (at the cylinder) until fuel flows out, then tighten it and do the next one. That should get you started.
Thanks for your help.
Unfortunately, changing the fuel filters did not fix the transmission shifting problem I had written earlier. Tomorrow morning I will look for the moderator valve like you suggested.
My question is- if I have to take the car to my mechanic, will I damage the tranny by driving about 20 miles? It shifts jerkily from 1st/. to 2nd. but then it goes upto 45mph and 4500-5000 rpm before shifting higher.
If I cannot find some obvious vaccuum leak, I'll have to take it in.
Thanks.
Yep, looking for a loose vacuum line or loose T-fitting is a great idea...it doesn't take much of a leak. Sometimes these lines are dislodged when people change the oil filters, as they are close by.
Glad to hear the plunger worked---now you know!
1) I found the vaccum line that runs from near the oil filter down to the tranny, and did the "tongue test" - it holds vaccum fine. I unplugged the end from the 3-way fitting and sucked on it and held my tongue.
2) I removed the green small round thing just before the 3-way fitting (I think it's called the surge damper?) and blew air thru' it- it blows fine; no restriction.
3) I started the engine, and removed this green damper along with the vaccuum line, and felt for suction from the white plastic part- could not feel any on my finger.
What is that white plastic part? Is it the vaccuum valve, or is it part of the vaccuum pump? Can that white part be bad and needs to be replaced?
Picture shows what I am talking about.
My door locks stopped working about a year ago.
Last 2-3 months, the hot air does not blow (cold air blows fine- i.e. not a/c; just regular cold).
Could all these be related to vaccuum? First the door locks, then the hot air, now the tranny shifting? Where is the vaccuum pump that lots of people have talked about?
Thanks,
and what are the four buttons for above the climate controle.
Thank you
The four buttons direct air flow to various places as I recall.
Thanks
If you have ZERO or close to zero oil pressure AT freeway speeds, you have a serious problem I think.
Perhaps you could have a very worn oil pump--not sure how much of a hassle it is to extract it and measure the wear in the gear teeth.
Maybe if you posted your readings we could say more:
cold idle reading
hot idle reading
hot freeway reading
PS: if oil pressure is near zero, don't do the freeway test.
The car is very nice but GUTLESS. When the turbo finally kicks in at about 2500 RPM, it does eventually move.
The engine was pretty dirty and like every other car I've ever purchased used, I took it to the car wash and washed it. I wasn't too concerned because there isn't a distributer to get wet. After the wash however, it was very sluggish. Hard to believe because it was pretty bad before and getting worse is actually an amazing feat.
I went ahead and did a 0-60 time and got about 20 seconds. I am at 6000 feet elevation. I got the car because it is obviously well made, but its slow enough to be borderline dangerous. Very poor acceleration until the turbo kicks in.
After I got the car home, I noticed that I had some leaking around the fuel injectors/plugs (4 of them to be exact). I am assuming I need to tighten?
Any suggestions regarding first steps to a tune up would be much appreciated.
Thanks,
Sam
So this gives you a power to weight ratio of 1:33. This would be the equivalent performance of a brand new Corvette (500HP) weighing 8 tons.
Best thing you can do is have a compression test done (needs a special tester) to see if you are dealing with a full deck. Also you can adjust the valves and dope the tank with some injector cleaner (like BGK44, not off the shelf $2 stuff).
But I have driven a normally aspirated 300D up to 8,000 feet and I could have walked faster I think.
If your compression is good, I'd suggest another type of car for your needs.
I am not after a fast car for my daughter. I am after a safe and slow. Right now the car accelerates so poorly that it is simply unsafe. It isn't just slow, it's a serious slug. I seriously doubt that this is normal. Even for a slug, it is bad.
I assumed the car was actually heavier that you posted. If it is 3300 pounds, that's relatively light. I would guess more like 3800-4000.
In any case, I did spot some leaking around the injectors. Surely this is both abnormal and is causing a compression loss. Is there a special tool used to tighten these fittings?
Can you point me in a direction where I can get my feet wet working on this diesel?
Speaking of a Corvette power...
How about this one?
http://www.sammichael.net/ftp/painted/jlofront.JPG
http://www.sammichael.net/ftp/Engine%20bay/ebay2.JPG
I eat the Corvette Z06 for breakfast and Vipers for lunch. World's first NA Miata with an LS6 in it. I have all the speed that I want. I want safety for my kid. Just need a bit more pull off the line for her so that she isn't harrassed and flipped off by everyone and their brother.
I have extensive experience with gasoline, but no diesel experience. However, I learn very quickly and just need a direction.
Thanks,
Sam.
I own a '79 300D (non-turbo). To assess the soundness of your engine there are a few things to note. When starting cold how long does it crank before starting? When it starts what color is the smoke? How "noisy" is the motor on cold startup? When fully warmed up is there black, blue, or white smoke at idle? Any smoke during acceleration?
Try removing the oil fill cap with a warmed up engine idling. If there is excessive wear on the piston rings the blow-by through the oil fill port will be intense. Blue smoke out the tailpipe means valve problems.
Don't forget the obvious like all new fuel filters, new air filter, and the right oil for the temperature. Good luck.
I think the car is probably performing normally under the circumstances. They ARE serious slugs, especially at high altitude. But it's worth checking the compression; after all, it's an old car and probably has a gazillion miles on it, right? And the valve clearance, too!
As for turbo boost, I presume the gauge is reading normally?
Yes your calculations at 114 HP with turbo boost would be about right but I was figuring less at lowest rpm.
You might also be able to live with the car if you shifted it manually, from low on up through the gears.
But even brand new out of the box this car is going to be a bit of a slug without more oxygen. At 7800 feet my 300D would barely move--I had to go up a friend's driveway in reverse-- but was quite okay at sea level and I drove it 1,000 miles home.
So...compression, valve clearance, boost levels.