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Starting 300D engine on the Stand

2386 Views 14 Replies 4 Participants Last post by  Brobrad
I had a guy from wisconsin ship me a 300D Engine. Once i got it the story on the engine, to the best of my recolection, had changed. None-the-less, with apprehension i have proceded to mate it up to my transmission. I put a new intake/exhaust gasket and a valve cover gasket on. I poured a little fluid in tranny and a couple of quarts of oil in just for good measure. I'm just wanting to see if i can get fire. I made make shift tank (like diesel purge) and primed it up. There was a lot of drag on the starter. I pulled it and took it to a parts house. they said it is fine. I then installed and used jumpers from my F-250, still dragging. I doulbed the cables and used a marine battery along with the F-250 cranked. It turned over a little faster, but no pop. I sprayed a little starting fluid but no fire as it was still dragging. I connected a hot wire to a few of the glow plugs one at time to heat it up. I heard the starting fluid fire off in one cylinder. Anyway. I'm not going to let it run, i just want fire before i lower her in. Any suggestions on getting enough juice to her would be great. I have just been giving a little throttle from the injector linkage. There may be something else keeping combustion down. Any help would be greatly appreicated.
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Pre Glow

I have not connected anything except the starter. I'm not sure what is meant by the Pre-glow system.

Have you connected the pre glow system at all?
When i "ordered" from they guy he said it was an 84 but in later conversations he indicated 83. It has the pencil tip glow plugs. I had hooked direct 12v to it from battery just to see if it got warm. The external portion never felt warm, but i heard the starting fluid ignited with a little pop when i energized one of them. I still am getting a great amount of drag when i go direct from battery with the jumper cables.

Glow plugs. If they are not operating the engine will not start. What year is the engine? There are two styles of plugs which are handled differently.
Be careful just whacking 12 volts onto these glow plugs - you could kill 'em. It is best to run them through the relay as that not only cycles through the glow plugs but it cuts out if they get too hot.

As for using glow plugs - well a good engine will start without them so long as the ambient air temperature isn't too cold - it will just take a bit longer => a few more cranks - not hours and hours!

You can replicate the effect of glow plugs by blowing hot air into the intake manifold.

If you have a block heater you could use that too to get some warmth in there => but only use it if you've got coolant in there...

If I were you I'd change the engine oil - that will help it crank faster.

If you're cranking it on the stand - I'd be more inclined to do a compression test...

...and if there are problems move straight to a leak down test...

I made a make shift harness and energize the glowplugs for about 5 seconds and disconnect and cycle again. I hit it with starting fluid and start cranking. I still can't get the starter to really spin her. I'm not sure what the deal is. I have it hooked to my f250 with one set of cables and to a marine battery with another set. So, i'm hitting it with two batteries and the alternator charge. Anyway, i put the marine battering on charge to make sure it is hot.

I got it to act like it wanted to crank about the time my starter got hot. I don't have the tools for a compression check or i would. I feel like it is good, but i don't have a lot of confidence in my "supplier" since several things were inconsistent. Again, all help is appreciated.
May be answers to some of these questions will help =>

Have you checked the valve clearances yet?

Does is crank over more easily with the glow plugs removed? (I hope so!)

What does the air filter look like (dirt wise)?
I'm just trying to get fire right now. I am not starting it per say. It does not have the filter in place. I have not removed the glow plugs to see if ti makes a difference. No, i have not checked the clearance.

Would the tranny being bolted up to it make that much difference? I wanted to start it without it, but the tranny housing is what bolts the starter on. I could get shorter bolts and see if that is the issue. I first tried to line it all up and the transmission would not mate fully. I pulled it back apart and messed around with the torque converter until it popped a little further down. It mated right up and there was no clearance left to be closed by pulling it up with bolts. I knew that would bust pump and possibly ruin torque converter. Still at a loss here:mad:
Pulled Glow Plugs

I pulled the glow plug at the flywheel end and the engine turned over much faster. I pulled two more glow plugs and it spun pretty good, but still slower than my other 300d when starter is engaged. It doesn't sound like it is fast enough for start speed. I did get white smoke from the exhaust so that looked promising. I only have a couple of quarts of oil in it, but it is pumping it out of the filter houseing when the engine turns over. I have poured a bit down the head to lube the cam etc. I can not imagine the valve being tight enough to cause it to drag as it does. This is very puzzling.

In consideration of my last post, i am wondering if i can put 24volts to the starter to see if it would crank over better.
I think you need to check your valve clearances - they tend to tighten on these engines not loosen.

Do you have access to another starter?

A user called funola on the peach parts forum was testing starter speeds and he found quite a difference in old and new

An OM617 starter motor is for LIFE not just for Christmas! - Page 2 - PeachParts Mercedes ShopForum
I got a larger diameter battery cable and went straight from the battery. It turned over really well. It still was a little slow, but i think it should have started. Any ideas on how i might get ti to bust off. I'm afaid i may have slight air leak on the hand primer. I pumps full and i see fuel coming out of the return at a really good rate, but it doesn't take much air to keep a diesel from cranking. Any suggestions on making sure i'm not pulling air.
Could the shut off valve be causing my problem

I have no vacuum lines hooked up and i am not sure if any of that makes a difference with the injector pump and shutting off the engine. I'm grabbing at straws here.

Further, is there any adjustment i should make to the injector pump. I have moved the throttle up and down during the start attempts, but have seen no change.
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