Open Source Plug-In Hybrid Super-Truck

[bennelson]

I replaced the glow plugs and the fuel primer pump.

https://www.youtube.com/watch?v=gTtq_Pa16ko

https://www.youtube.com/watch?v=U1dhIT5Wb-U

I dug up a Mercedes 4-speed manual transmission at a junk yard. I took the bell-housing off of it and fit it up to the engine.

I think I can use the bell-housing from the Mercedes transmission on the Chevy transmission and get it all to work. I'll have to make some sort of custom plate to connect the two, but the Mercedes bell is an inch shorter than the Chevy bell housing, so I think I have an inch to work with for an adapter and spacers.

[arcosine]

There a guy that put a Mercedes diesel in an Astro van, the thread is on this site. I think he went with a 5 cyl turbo engine after using the 240. Go with the 95 or 94, s-10 and don't worry about emission testing. The same laws are here in Illinois, they test only ODB2, 96 or later. I was just looking at s-10 rear axle ratios yesterday using an 2.14 axle ratio and a .73 5th gear the engine would turn at 1300 rpm at 65, a little slow, maybe a 2.53 ratio or 2.73 would be better.

http://www.sierragear.com/gm-rpo-axl...ation-codes-3/


http://ecomodder.com/forum/showthrea...sel-26437.html

[Daox]

Woohoo, nice to see an update on this project!

[bennelson]

Arcosine, thanks for the link to those GM codes.

Here's the inside of the glovebox on my truck.



One of the codes is GT5, which indicates rear gearing of 4.10. I believe this was the lowest stock gearing available on S-10s. That would make sense, since it's the 2.2l 4-cylinder (less powerful engine) AND extended cab, which makes it heavier.

I believe that the low gearing would be a disadvantage to the diesel engine, but an advantage to the electric motor. Likely, I'd have a relatively low top cruising speed on the diesel. If it were somebody else, that might be a problem, but I don't mind keeping my speed reasonable on the freeway.

I think the 4.10 gearing should be fine.

EDIT: I also looked in the junk truck. That one says GT4 on it, which would be 3.73 gears. That truck really is junk. I only have it as something to test-fit and experiment on. I wouldn't want to use it's whole rear differential, but if I really wanted to, I'm sure I could take it apart and get that gear out.

[bennelson]

I did a little work looking at the differences between the Chevy 5-speed and the Mercedes 4-speed. I'm planning to use the bell-housing off the Mercedes manual transmission and install it on the Chevy 5-speed.

https://www.youtube.com/watch?v=Kcf_tyY23dc

SuperTruck: Mercedes Manual Transmission

[arcosine]

There is a wide range and narrow range chevy 5 speed. The wide rage has a lower first gear:

The T5 page

[bennelson]

I did a little more work with the transmissions.

I got the bell-housing off the Chevy T5. It was pretty easy, just four bolts from the outside, then pry. It came right off.

One thing I discovered is that the tip of the transmission shaft on BOTH the transmissions is 15mm. That means that I SHOULD be able to use a stock Mercedes pilot bearing in the crankshaft, instead of finding/making something custom.

The length of the shaft on both transmissions is pretty close too. The T5 is just a little over 7 inches. When I measured the depth of the Mercedes bell housing on the engine, it was just under 7 inches to the mating surface. I think that I just need a 3/8" or 1/2" adapter plate and I will be all set.

At this point, I'm leaning towards using the Mercedes bell housing on the T5 transmission, with an adapter plate between the two. The bell housing will fit stock on the engine without having to move the starter and will have perfect alignment. I won't be able to use the original slave cylinder position, because the T5 transmission is too big compared to the little Mercedes 4-speed. I'll need to cut into the bell somewhere on the left and add a slave cylinder there.

Also, I've been sick of staring at the 6 flywheel bolts that have been holding the flywheel to the crankshaft. The bolts used for the torque converter are LONGER than those used for a manual transmission flywheel. They can't be threaded all the way in without hitting the engine! So, for the moment, I used washers and oversized nuts as spacers, which worked fine to hold the flywheel on. A friend dropped off some diesel related stuff a while back, including an assortment of flywheel bolts. (I think they are off old VWs.) They were all the right thread pitch, and I found enough matching ones to hold the flywheel on. When I looked up the bolts, I was surprised that they are $8 each, and 12 are required. Yowza! I just saved myself $100 if I can use these other ones!

https://www.youtube.com/watch?v=-APqMk6umqs

PS: Here's more about it on my blog: SuperTruck: Bell-Housing

[Daox]

Sounds like you have a plan. Are you going to make the adapter plate yourself, or have it made at a shop?

[bennelson]

I'd prefer to make it myself, both to save money and for the experience, but I do need it to be properly aligned.

When I did the plate for the Electro-Metro, I did all the measurements and figured it all out, and then took it to "Hot Rod Jim", who is a machinist by day and hot-rodder on nights and weekends. He basically CNC'ed an adapter plate for me on his lunch hour. He was also a great source of advice and helped me out with a few other things.

I'm hoping to get a chance to visit with him and pick his brain on making the bell adapter plate.

[bennelson]

Here goes with a mock-up of the transmission adapter plate.

I had some 5/8th" plywood handy, so I thought I'd give that a try. I flopped the bell housing onto it, traced that, and marked the holes.

Next, I tried putting the entire transmission on the plywood, before I realized how much lighter and easier it would be just to trace the Chevy bell-housing instead, as that is the exact size and shape of the transmission anyways!

I traced that and marked the holes. I drilled out all the holes, then jig-sawed out a five-inch center circle for the raised area in the center of the transmission.

With that, I was able to mount the plywood to the transmission, then the bell to the plywood. It's not perfect. I quickly saw where I will have to counter-sink some bolt heads or tap and thread the plate, but that's kind of thing I want to learn by making a mock-up!

I got the engine, bell-housing, plywood adapter plate, and transmission all together. Suddenly, it started feeling like this project was really going somewhere.

https://www.youtube.com/watch?v=ACELZl9Oabs

More blog and photos at:
Plywood Transmission Adapter Plate