Deutz MAH 916 Black smoke but not running

[iff7378]

I've been working on this engine on and off for about 4 years now!

Backstory for those interested - I bought this at an farm auction partially disassembled. Most things were rusty, the piston was badly scored, the crank needed regrinding, and the cylinder liner was pretty worn. I wanted it badly because you rarely come across something like this in the USA.

The list of repairs and replacements ive done for this engine is quite extensive - everything was disassembled and cleaned thoroughly.
I had the crank big end reground and new big end bearings made. I bought a replacement oversized piston and rings from Germany (I spent the same on this piston as I spent on the whole engine at auction!)
The cylinder liner was bored and honed for the new piston, the injector and injection pump was cleaned and rebuilt.
I made new gaskets all around, brazed up new fuel lines for everything, and had the cylinder head machined flat as well.

Everything is looking pretty good! Lately, its time to start getting this engine to run!
I couldn't buy Zundfix diesel starters so i ended up making my own (tissue paper and potassium nitrate).
Unfortunately the most I get out of the engine is a puff of black smoke out the exhaust but its not taking off and running. I know it's getting fuel, it has loads of compression (perhaps I should measure the pressure) and I think the issue is related to injection timing.

Which brings me to the confusion as I have tried every combination of shims behind the injection pump and nothing seems to change the timing of the fuel injection. Right now it seems to inject right at TDC, not ideal as we should be 20 degrees BTDC. I shimmed the pump with 1.6 mm of shims, same time of fuel injection. Tried no shims at all, same time of fuel injection. I'm kind of at a loss now.

Hopefully someone with experience with these old diesels can weigh in and help!!
I am so close to a running engine but not quite there yet.

I'm not the best at consistently taking pictures of the progress, but I've attached a bunch from over the years.

[cobbadog]

nice project to keep you out of trouble for a while

[sirpedrosa]

Ian, Gentles

Lets start. I think I saw one of those pics sometime ago, but....

The hopper stud is 5/8 unc straightforward, to put a new one, just buy a 5/8 bolt.

Zünfix go here: https://www.oldtimer-kuepper.de/epages/61009898.sf/de_DE/?ObjectPath=/Shops/61009898/Categories/Z%C3%BCndfix
or here: https://histoparts.com/accessoires/toebehoren/startlonten

And yes, all parts from Germany are expensive, very expensive.

The selly question: Is it perfectely timed? (My thread was clear enough?). If so, take a look at my Lister thread here: https://listerengine.com/smf/index.php?topic=8320.msg102965#msg102965

Is your injector certified at 120ATM? This is an low compression engine - thats why it needs starter!

Is you IP element and plunger ok? If all checked now las thing is the quantity of shims. The more, the late! the few the knoking. CASPICI?

Just my 10 cents... for now.

Cheers
VP

[iff7378]

I enjoy that parts of these engines are metric thread but there are some random inch bolts. The head bolts really threw me off being a metric diameter with an inch pitch. I ended up having to machine my own nut as my engine was missing one.

I did order zunfix for the engine but they were out of stock for a very long time. Presumably COVID related. Finally I was able to place an order. In the meantime, they are not hard to make at home.

I have not pressure tested the injector, perhaps that would be a good idea to do. I wonder what funny looks I'll get at a test shop in the USA with an antique German injector.

I'm planning to do some more work to the timing this weekend and I'll post an update in a few days.

Much appreciate your help!

-Ian

[sirpedrosa]

Ian, Gentles

You are trully wellcome!

Your engine got the scars of WW2, US occupied Köln and all German industry had been destroyed.

Injector has 1/2UNC studs, and governor lever has 1/2 19TPI AKA japanese gas.

Injector is set by shims.

Cheers
VP

[iff7378]

I worked on this some more last night and determined with no shims the injector seems to be popping at about 12 degrees BTDC. I'm still only getting black smoke out the exhaust but I would think the engine should run.

I think I'm going to pull the injector and have it pressure tested to rule that out as an issue. Although, I think even if the injection pressure was low, the engine would still run. It is definitely injecting fuel into the cylinder.

More investigation to come!

[cobbadog]

From my failing memory 1/2" x 19 TPIK was British Gas pitch. It was used on my David Brown Cropmaster big end bolts.