Mercedes 300D

autojunkyjosh

Hi my name is Joshua, I own a 1981 MBZ 300D. I have a couple of questions.First of all how many speeds is the AT it only has DSL but I count 4 sometimes others only 3.It also shifts kind of hard is this normal?It has 135000 when the odometer died in 1999 and I am constantly adding oil.The body and interior is in perfect condition except for a few flaws in the paint, and I only paid $2400 fort it.I love the car, but am thinking about switching to the wagon counterpart 300TD, I also like the Volvo substitue and don't know which one is better, but I do prefer the diesel engine.(mine is non-turbo)What are some things to do to it except for changing the oil, I am not sure where the two fuel filters are. I need a referral for brake pads also.Finally, I was told that the secondary electric fan should not stay on all the time but mine does. I also have automatic climate control which is very ornery a/c works sometimes and the heat only works after a long distance of driving.Any suggestions or comments would be appreciated. Thanks

Mr_Shiftright

Okay,

You have 4 speeds on the automatic.

Hard shifting is normal

Climate controls are troublesome but can be fixed or rebuilt to work right

Volvo diesels are not good in the cars they sent over here. Forget that. TD wagons are great, that would be a good choice.

Oil consumption could be leaks (the oil filler cap is one suspect) or just engine wear. Diesels run on very high compression and so if they weren't cared for they will blow oil past the rings.

The filter system is very important. You should buy a book that tells you the location of the filters. Also be sure to use a diesel fuel additive at every fill up, and if you can find it a "cetane booster" (like an octane booster for gasoline).

lancerfixer

I love old Volvos myself, but avoid diesels like the plague. Their 8-valve four cylinder gas engine, though, is a great, reliable motor, either with turbo or without (more so without, of course.)

burdawg

Your 4 speed auto probably starts out in 2nd under most cases. To start in 1st you have to manually shift or push the accelerator pedal down all the way when pulling away, as long as it's adjusted right.
Hard shifting is normal but you should notice a definite difference under different driving habits, i.e. harder shifting under hard acceleration.
Not surprising to use lots of oil in a diesel.
A good rule of thumb with this engine is if it starts easily once the glow plugs are hot the compression is probably OK. If it's hard starting it MAY be a sign of low compression.
Don't ever let it run out of fuel, it can be hard to get it re-started.

autojunkyjosh

I have no trouble starting it, although it was surprising that the glow plug indicator stays on for maybe only two seconds.
The most noticeable jerk in the trans is under hard acceleration, it also takes it a few seconds to go from D to Reverse. When I come to a stop sign it is like it switches to neutral and when I start on the accelerator it kicks back in.
I was also told that there may be a valve? switch? to adjust for elevation being that I bought it from Florida which is very flat. I live in a higher elevation.

So stay away from Volvo diesels but the gas engines are good.
I just can't decide whether I like the Volvo or the Merc. I am in EMS and I need something that can take a little abuse (acceleration, brakes, etc) that is my only scare now cold engine starts on calls.

Mr_Shiftright

Diesel fuel additives will help diesel cold starts. Also, if the weather is severe, you can add a small amount of gasoline to the fuel, but really, not much more than 10% would be my recommendation.

These cars just shift hard and I think you'll have to learn to live with it.

As for altitude, diesels do suffer from altitude...this is probably why turbo diesels are preferred in the mountains....although I've driven my 300D up to 11,000 feet and as long as you stay moving, it's not bad.

lancerfixer

Whaddya think? Either way sounds good to me. I really don't think you can lose, josh. Check out http://www.brickboard.com for more info on Volvos than you ever knew existed.