Back again for help from the experienced diesel owners. I have changed all filters , fuel lines, drained tank, put in additive and adjusted valves. This helped some but the engine surges moderatly at 1500 rpm, lacks power and top speed is 65-68 mph.
The 1983 300d [236k] starts extremly well even on cold mornings.
Thanks for any help, Paul

P.S. The turbo is o.k but I'm not sure about the EGR. Could this cause this much of a problem?

Pull the vaccuum line to the EGR and see if that helps -- usually an EGR sticking open will give low power and lots of smoke at low speed, but high speed will be nearly normal.

Your alititude adjuster (ALDA) may be out of adjustment or bad, too.

Check the little pressure lines from the intake manifold to the ALDA, too -- you may have a plug at the manifold or a bad overpressure valve -- this vents the boost pressure off, so that it doesn't reack the ALDA, preventing the addition of extra fuel. These go bad with age, resulting in low power. Ditto for boost lines -- the rubber either gets mushy or rock hard and leaks in either condition.

If you don't have smoke, you have a fuel delivery problem, hence low power! If you have clouds of black smoke, you have low compression or bad injectors.

There is a faint possibility the IP is bad, too, although I doubt that, they usually don't go bad on all cylinders at once!

There is one IP problem you need to check, though -- there is either a pressure valve or bleed hole in the banjo bolt on the return side of the pump -- if this is plugged you can get running problems, although not usually restricted power.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Thanks Peter for your response. I replaced most of the vacuum hoses [short rubber] and the over pressure valve [borrowed from another car]. also found that the EGR valve is functioning ok.
There is no smoke at anytime. The ALDA still had the plastic cover intact. I removed it but have not made any adjustments yet.
The car starts very good and idles smooth for a diesel. . I bought the car a few months ago. It had goog maintaince until about 2 years ago when the owner said it began to lose power biut he didn't realize the flex pipe on the exhaust was gone and fuel filters had [algae ?] He lives on a mountain so it wasn't driven much after lately.
I saw a post on adjusting the ALDA. Should I try that ?As I said earlier, it has no power,slow to respond even in neutral it revs so slow.
I appreciate any help I can get .
Thanks,
Paul

Paul:

If there was an algae problem you have a plugged tank screen, most likely, and the only thing wrong is no fuel at the IP.

The "cheap and cheerful" fix is to blow some compressed air down the fuel supply line -- gently, please, with the tank cap off so you don't pressurize it and blow fuel everywhere! This will hopefully get all the algae off the screen on the tank pickup. If it does, you will have normal power until it clogs up again. If you don't get bubbling in the tank, you also have a plugged fuel line and will need to clear it.

The real fix, especially if you do get proper power after blowing the line out, is to replace the tank screen after having the tank removed and cleaned.

Big pain in the butt. Use RedLine or other diesel additive, or a marine algicide regularly for a while after cleaning to prevent this problem from re-occuring.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Thanks for your help Peter. I did most of the things you suggested and decided to tear the plastic off the ALDA. It worked!! Compared to before it's a "hot rod". Ran it 80 mph today for the 1st time in it's life.
THANKS TO EVERYONE FOR YOUR HELP. I AM SURE I'LL BE BACK FOR MORE. I'm excited about my 300d again. eady to look for those vacuum leaks now. Thanks Again
Paul