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My 1986 300SDL Turbo was running well until Cylinder head cracked and pressurized the reservoir. It did not overheat...even when pressure cap was burping. I have had the head repaired and all new valve guides and seats and valve job, While apart I put new timing chain , oil pump chain all chain rails and tensioner. Sent Turbocharger out for rebuild , sent injection pump and injectors out for inspection. I have installed all new glow plugs and replaced the fuel lines and filters , including replacing the fuel strainer screen in the bottom of the tank. Now the car will not go above 30 mph on a long grade. I have checked for linkage going to Full throttle. I installed a new EGR valve , but even disconnected it as I have been told it is a POWER robber. When I sent the pump out for inspection , I got broken in the return Shipping. My pump re builder was very accommodating and said he had some extra parts and would assemble / repair my broken pump with the donor pump he had. ( The damage was 1 of the 3 mounting ears broke off ). I have been so frustrated with all that has been done and the car is not road worthy. ( It will run up to about 60 mph on the freeway ). It also does not start nicely on the first try as it should , especially with all new glow plugs. My daughter has virtually the same engine ( OM603 ) in her 1987 300 TD wagon, her car starts GREAT and runs Strong with 390,000 miles. I tried to be pretty accurate with the pump timing , using the special tool that inserts into the side of the pump. I also verified Exact CRANK PULLEY Markings with a dial indicator when head was off. I have done an engine compression test and have 400 psi in every cylinder. I am suspicious of the pump ?? I have not done a turbo boost test nor have I removed the exhaust system to check to clog., but it does blow smoke out the tailpipe when rev-ved up.
Can anyone shed some light or a direction to go next ? If the pump was incorrect would it behave this way ? Thanks for any feedback
 

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My 1986 300SDL Turbo.......... Now the car will not go above 30 mph on a long grade. .................
Can anyone shed some light or a direction to go next ? If the pump was incorrect would it behave this way ? Thanks for any feedback
Crossover pipe on OM603 gets packed w/goo, reducing effective air passage (internal diameter). Requires removal and thorough cleansing w/Kerosine (Diesel #1). Same goo accumulates further inside. So, for a more thorough cleansing, spray lots of Kero while crossover pipe is off. Since the spayed kero (to soften and wash goo) will eventually drain into oil pan and dilute the oil, good idea to let car sit overnight. Then, change oil. Engine at rest is assumed during entire cleansing operation!

Sock in fuel tank filters only large pieces of crap. Over time, junk accumulates and sits at tank bottom. good idea to have it PROFESSIONALLY washed; professionals are aware of, and watch out for delicate/intricate tubing inside OEM tank. Depending on your location and ambient temps, not a bad idea to double-glow: 30 secs, don't crank, another 30 secs, then crank. Ability to interpret diagnostics built into dash glow-plug indicator is helpful.

The only two ingredients to reliable startup and power are AIR and FUEL. Now that air intake is taken care of, focus on "No air" in fuel lines. Fuel circuit of SDL (actually, all diesels) is designed to self bleed after (2X) fuel filter service, unlike older 240D with manual prime pump. However, loose connections wipe out that built-in blessing. Lastly, ensure glow plug cavity is de-carbonized. Special tool for reaming OM603 is required. Follow instructions; grease at end of reamer prevents carbon from falling back into cylinder. Carbon build-up leads to weakened glow.

Recommend highly that you upgrade oil pan to 1987 version design. Nothing but an add-on cap; bolts on 1986 OEM pan's side. You'll be using 8.5 oil qts instead of current 7.5 qts. Advantages are obvious.

If interested, watch buy/sell section here. I intend advertising a bunch of Bosch glow plugs for 603 eng, including updated, fast warming replacements.
 
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