Injector Overhaul
 

I just completed an injector overhaul using Tomasspin's web site manual. The engine is a OM 617.910 in a 1976 W115. I must say the difference is awe inspiring. Quieter operation, smoother idle, smoother acceleration. Still not a dragster, but what can you expect from 80 HP? If any of you are planning on doing something such as this, check out his web site first. The guy knows his stuff. Incidently, for the tune up, (injector cleaning, vavle adjustment, and checking the IP timing), I have a total of around $30.00 invested in a cam cover gasket and some return line tubing. I shudder to think of how much the shop would charge for all that.

Happy Dieselling!!

Hawk,

You almost have me convinced to clean my injectors. Maybe when the 300SD hits 250,000 miles which should happen this year.

But it runs so good now, I hate to touch anything, you know if it ain't broke, don't fix it.

It starts so eazy when warm, its almost like the starter isn't used. The engine just seems to start running when the key is turned.

P E H

What did you do to consider them "rebuilt"

Did you check pop pressures? Did you clean them? Inspect spray patterns? replace seats?




Michael

PEH My 300sd also starts real easy. I got the car in march this year, and have not checked valves or timing chain yet. The motor just runs so good, I don't want to touch anything. steve

Mostly it was a good thorough cleaning, and inspection. Then I had a friend who is a diesel mechanic with his own shop check the popoff pressures. You have to be sure and lube the parts with a good lightweight oil such as WD-40 or Mouse Milk when assembling them and for gosh sakes keep everything CLEAN!!. By doing this I just assumed the spray patterns would be good and judging by the way the car now runs I lucked out. I replaced the heat shields and return lines. The only problem I ran into was #'s 2 and 3 injector line B-nuts leaking at the delivery valve end. I solved that with an aviation product called "Fuel Lube". (See Post).

I'm sorry if my tone yesterday was wrong(?)


FYI, if you decide to rebuild the injectors by replacing the seats and needle. It's the same job again. The one thing the hd bosch guys told me-most of the tolerance is the machining of the body. Ie a matched set should remain matched with a rebuild.

Spray pattern can be a huge problem as is leaking. Can kill an engine-that's why I asked if you did test the injectors.

For being quite, actually a rebuild injector should have a definate noise. Quite is a possible indicator of them needing overhaul. But, since your friend has the tools, I'm sure he's giving you advice.

Michael