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Starting 300D engine on the Stand

2383 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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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...
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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 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
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