Mer-Chevy Project: Biofuel 40mpg Pickup

[bennelson]

Nah, the S10 flywheel wouldn't work on there. totally different weight very different bolt pattern. With all the bolts the Mercedes crank takes, there wouldn't have been any flywheel left to the S10 one.

I am planning on using the S10 transmission.

In the photo two above, you can see the "adapter ring" to the right of the mercedes engine and flywheel. That is a transitional piece between the engine and transmission, which should be handy to figure out how to mount the new tranny.


Actually, you got me. I am just making this all up as I go!

I have never done anything like this before.

Built an electric car - yes, that wasn't that tough.

[Christ]

Originally Posted by Christ

I may have asked before, but was there any way you could have had the flywheel redrilled to match the crank pattern of the Mercedes engine?

It might have been easier that way, unless the S10's clutch disc fits inside the pressure plate for the Mercedes flywheel.

(I presume, here, that you're still using the S10 transmission, right?)

Excuse me while I get a beer and think...

Ok.

There are two things you need to do at this point, to ensure that things will work out for you:

1 - Make sure the flywheel for the OM617 fits in the S10's bell housing.

2 - See if the clutch disk for the S10 will fit in the flywheel for the OM617, and that the pressure plate for the OM617 will apply pressure on the clutch plate.

If the S10's clutch plate will fit in there, and the pressure plate will apply sufficient pressure to you, you're golden as long as you can get the transmission lined up and the input shaft at the correct depth.

Another option is to see if, by chance, the OM617's clutch plate fits the input shaft of the S10's transmission. If the hole is entirely too big for the input shaft, consider having a machinist make an adapter for you (that will make parts easier for you in the future, because you can then buy just one clutch kit for the vehicle.) to bring the S10's input shaft up to the correct size/spline count.

To mount the S10's transmission to the adapter plate, do the same thing many do with EV conversions, lay the transmission centered in the plate, and spray paint around it, making sure to fill the holes. Drill the adapter plate, then install fasteners of your choice.

Both flywheels look to be close to the same diameter, so fitment may not be an issue in that respect.

You'll want to line the engine and transmission up at some point to make sure that the transmission's input shaft is the correct depth into the flywheel to engage the clutch properly.

This weekend, I can check a few things on my OM616 and report back for you. I have an S10 transmission laying around, as well, to check the sizing for you.

The 616 and 617 share backends and transmissions, so the measurements will be the same.

[Christ]

OH, and I envy you for having built an electric car. I also support you in this project, as well.

I'll be doing something similar very shortly, only in a more modded way, and with a Ranger. (I'm going to slam it and put a single stack on it, with slab sides, etc... I don't intend for it to haul anything, except groceries... LOL.)

[bennelson]

Thanks Christ!

[Christ]

NP, I'll grab those measurements when I'm at my Father's house, Saturday or Sunday, for you.

[bennelson]

(As to Christ's comments above...
1: The diesel flywheel does fit the S10 bell housing.
2: See if the clutch disk for the S10 will NOT fit in the diesel flywheel.)




The second and third Sundays of the month are usually “EV Build Days” – but the friend who usually hosts them was out of town. Instead, I invited EV club members over to my house to help figure out the next steps in the “MerChevy” diesel truck conversion.

Rich was the first to show up, and the main guy I really wanted to talk to. We looked at the flywheels and started kicking around ideas. A couple other guys showed up as well, enough to get the ideas flowing, but few enough that we weren’t just tripping over each other.

The goal – figure out how to mate the Chevy transmission to the Mercedes engine.

The problem(s)? The Chevy clutch disc is too big to fit in the Mercedes flywheel. The Chevy flywheel can not be redrilled to fit the diesel engine. The Mercedes flywheel can not be drilled to fit the Chevy clutch cover.

We also pulled the bell housing off the automatic transmission from the Mercedes to take a closer look at that as well. Then I called up Hot Rod Jim, who lives just up the road from me and helped with machining on my Electro-Metro project. We decided to visit, so the guys and I hopped in the Rich’s truck, with flywheels et al in the back and zipped up the road.

We spent the next 20 minutes to half hour standing around the tailgate throwing around ideas. Here’s the two main things we came up with.

Option A: Find a clutch plate that will match the 26 spines of the Chevy transmission, but only be about 8″ diameter, (instead of the typical 9″) that will fit into the Mercedes flywheel. Buy a new Mercedes pressure plate and mount it on there. Done. (after that, a custom shaft bearing and engine to tranny adapter plate are still needed, but that’s the easy stuff.)

Option B: I know this one sounds crazy, but….. Sandwich the two flywheels together. Trim all that extra weight off the Mercedes flywheel (yipes! machining!) but carve a step into it. Put the S10 flywheel over the top of it, and press it down into the step in the other flywheel. Bolt the two together. I would now have a flywheel that fits the crankshaft of the Mercedes, and the clutch, pressure plate, and transmission of the Chevy. I would be able to use all (cheap and easily available) Chevy parts in the future. The weight should also be very close to the weight of the existing Mercedes manual tranny flywheel. Two machinists and a diesel mechanic were in on this conversation. They didn’t think it was crazy. I did, but that’s beside the point.

So now Rich is going to see if he can locate a clutch that will fit both the Mercedes flywheel and the Chevy tranny. If he can, this project starts to sound fairly doable. If not, it just got a whole lot more fun/interesting.

[Christ]

I like option B.

The problems for me never end, I had to tow my Father's S10 elsewhere to get it fixed, and the power to the barn (where my parts are) is down right now. I wasn't able to get back in the daylight to get any measurements for you this weekend, but I will strive for them this upcoming weekend, if you haven't managed to get them already.

You must remember that if you have to use an adapter that is thicker than the existing one, you'll also need to space the flywheel so that the clutch is sitting at the proper depth on the input shaft. It may be best to machine the existing flywheel, so that depth can be properly considered when mounting the transmission to the engine.

My $0.02.

[bennelson]

I finally got somebody to buy a few Mercedes parts off me - including one door.

Since I am on a corner property, I now need to get rid of the Mercedes, or the place is going to start looking like a junk yard. I wanted to at least move the car up next to my garage, where a tree blocks the view from the main road, but couldn't do that yesterday in the rain.

So, today, with a little time and some nice weather, I shuffled around the Mercedes and the S10 in my driveway. It doesn't look it, but my driveway has a slope to it. Easy to push cars down my driveway. Very hard to push them up.

So, I threw an old rubber tire on the front of the Metro and put the forklift motor to good use - pushing cars! It's been a while since I had any reason to use first gear in that car. Low gearing, and no clutch to slip made it a cinch to shove cars around!

http://www.youtube.com/watch?v=00J9SXkoO-A

[texanidiot25]

You know what's funny? They made a turbo diesel version of this generation S10, for south america.

http://www.youtube.com/watch?v=yHO8MbMYZ3g

The front clip and bed are different, but that cab, and chassis is the same as our US S10. Quad-cab S10s are just uncommon, which is why most don't even recognize our little truck. I'd have to guess it's an Isuzu diesel, no less.

[orange4boy]

GASP! You used the teeny tiny Elec-trak tires. You brute!

I used my Elec-trak to move my dead Prius into the garage for the tranny swap. Electric drive rawks!