Mercedes 300 turbo diesel

[diesel smoke]

Hey, OM617. You seem to know quite a bit about these old cars. I found one relatively close to me for a pretty darn good price. This one: http://edmonton.kijiji.ca/c-cars-vehicles-cars-Mercedes-Benz-300-Series-300d-Sedan-W0QQAdIdZ156979275 Now, is there anything that I should really know about it before I buy it? Stuff like known problems that will arise? Stuff to check specifically? I would ask to do a compression check first. I know it has 300 000Km on it, but that doesn't really scare me much.

[OM617]

Its a good car, 300000km is not much. The only major thing to watch out for is a cracked cylinder head.

[diesel smoke]

Right on. That's what I wanted to hear.  I'm guessing that checking for a cracked cylinder head would be about the same as a VW in looking for oil in the coolant, coolant in oil, excessive blow-by, and low compression. I just hope they let me do a compression check first. I got one that goes through the glow plug on older Mercedes. About what PSI should I be getting?

[OM617]

300psi+ is good, 400psi+ is fantastic.

[diesel smoke]

Thanks. 

[Rabbit on Roids]

really? only from 86 and 87 cars? thats kinda a small window.

[dennis]

Its a good car, 300000km is not much. The only major thing to watch out for is a cracked cylinder head.

I would also have the glow plugs checked on that engine. They have a bad habit of breaking off in the head. Mercedes dealerships are about the only ones that have the tools to extrack the broken off part. If you ever have to change the glow plugs be very careful.
Dennis

[drrtybyl]

Out of curiosity, how much do these engines/cars weigh?  They seem like tanks -- maybe the drivetrain would yield better mileage swapped into a lighter vehicle?

[diesel smoke]

Well, I did go look at that car yesterday, and I think I'm gonna pass on it. There is more rust on the lower rocker panels than what is in the pics in the ad; and when I drove it, when it shifted from 1st to 2nd and 2nd to 3rd it was really rough. More like a hard shift with a thud and a jerk through the whole car. Any ideas as to what that would be?

[8v-of-fury]

To the OP, a DODGE will never hold it's value like a Benz

82 was a good year.

[maxfax]

Well, I did go look at that car yesterday, and I think I'm gonna pass on it. There is more rust on the lower rocker panels than what is in the pics in the ad; and when I drove it, when it shifted from 1st to 2nd and 2nd to 3rd it was really rough. More like a hard shift with a thud and a jerk through the whole car. Any ideas as to what that would be?

Kind of sounds like a vacuum control problem..  That is if they still used vaccum for the shifting in '87..

[dennis]

Well, I did go look at that car yesterday, and I think I'm gonna pass on it. There is more rust on the lower rocker panels than what is in the pics in the ad; and when I drove it, when it shifted from 1st to 2nd and 2nd to 3rd it was really rough. More like a hard shift with a thud and a jerk through the whole car. Any ideas as to what that would be?

 
Check modulator valve vac hose first to see if there is vacumm. If not, trace it back up to the engine. It is likley off somewhere.

[diesel smoke]

Ok, I'll check the vac line. Just so there isn't any confusion, where abouts do I have to look to find the line? Also, how is the turbo controlled? Is it vacuum controlled? When I drove it it seemed really slow for a inline 6. So maybe there is something else to be looking for.

[maxfax]

Here's the vac diagram for an '87 300D.. Maybe this'll help you out...

[diesel smoke]

Yeah, that does help. I'll call up the guy tomorrow and see if he is willing to try checking the hose himself. If we/he can get the transmission shifting smooth again, and I do a compression check that turns up good, I would reconsider buying the car and saving to repair the rust. The interior is near mint.