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Mercedes 616/617 turbo diesel Astro build

42719 Views 237 Replies 30 Participants Last post by  tinworm
NOTE- This is an old thread where all the images were lost due to broken links to photobucket in 2017. I have attempted to go through and upload images again, but some images may not necessarily apply to posts due to lack of availability years later

I been talking about this project, and after finally finding a "decent condition" Astro, time to start working on it!

The plan is to rip the OM616 65hp MB diesel out of my old Mercedes, adapt it to a NV3500 5-speed tranny, and put it in the astro van. The engine is also being mildly turbo charged. Its not built for it heat wise, but I should be able to get away with it, and a little extra oomph on hills would be much appreciated. Searching around, I discovered that the generation 2 passenger astro is only 600 lbs heavier than the 123 chassis MB I was previously using this engine in. I figure the generation 1 astro in the cargo version is closer to the 2 ton mark. The MB is around 3700 lbs.

Ultimately, for a fun swap project i am trying to build decent MPG manual tranny diesel work van. This engine was capable of 35 mpg in the MB with a .8 overdrive, the NV3500 I think is a .78, and I have to find a GM rear end that is close to 3.46, which was the MB rear end I had ready for my car. Stock, the 240 MB came with a 3.69, but with the turbo, a 3.46 would be better. Im not sure what the 1994 Astro has for a rear end, any ideas? If its not close, I will be grabbing another rear end from somewhere, or changing the gears.

Images of what the donor sedan looks like from wikipedia, the 207D that also was fitted with these motors (about the size of a express van), and a 1989 shorty recipient van-


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Hey, you're getting there. If it were easy everyone would be doing it. Good job.
Geez. put in a PowerGlide and at least drive it. :p
To spend thousands of dollars to build something that is only marginally useful to save $163 per 5,000 miles seems the perfect definition of pointless to me BUT, thank goodness in at the 49 states we can still build whatever we want and the hell with whatever somebody we don't even know on a forum thinks. I enjoyed your build thread and all the solutions you were able to make during it but wondered about it the whole time... Stan
That working can be a real PITA. I tried it but didn't like it. Did 30 years and 20 seconds at GM and have been retired since Dec '89.
Wow, That thing is sure putting you through the wringer. Progress is the cause of a lot of our trouble but it's usually well worth it when one finally comes out the other side. Hang in there, you will have a rare piece that fits your needs to a "T" at some point... Stan M
whats most irritating is that 100% of my drivability issues with this conversion have to do with trusting the provided parts of a purchased adapter kit, vs making one.

Im on 5 different removals and reinstallations of this T5, all related to what I now am aware is an incorrectly depthed pilot bearing adapter. Its just not designed properly, its much too shallow a mounting point for a stock GM pilot bearing. Had I just figured it out for myself and made my own adapter using a GM flywheel, I wouldnt have been in the position of redoing it so many times.

Now that im in the mindset that every part of the adapter kit might not be designed perfectly, im much more likely to get this figured out for good, but in the process may have damaged a gearbox that only has 8k on it since being rebuilt. Oh well.

Just goes to show, anything worth doing, is worth doing yourself.
Amen to that brother,,,
I think we tend to judge people by ourselves and assume (there's that word again) that people will design something that will do what they say it will do before marketing it to us.
How do "They" know where to put the flywheel on the assembly line? It would seem that say, if the engine is at TDC on #1 cylinder, the flywheel weight should be in "this" position. This mess is just too weird for my miniature mind.
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