My 1956 Cletrac OC-3

[Anthony]

Well it has been quite a while but i am finnaly getting close to getting this beast done.

Blake...i will send you some pictures in an email so if you want to put them in the album you can. I only have ones of it without the hood now but i hope to get the hydraulic pump and alternator mounted as well as my anderson blade. I will send more once its all done.


I took a nice '67 mercedes benz OM621 engine and put it in my cletrac. The gas was frustrating because even though it started beautifully, it is a gasser and the governor spring was never set right and i was tired of trying to get it right. I am a diesel person myself Good old 7.3 idi ford. The hercules pushed dirt just fine but i had to use 1st in the model a aux trans and 1st in the cletrac trans to really do much.


Just thought it would be neat to share what i have been doing lately.

See Below for pictures. The radiator is going to be straightened later.

http://good-times.webshots.com/album/561881412ptCzFD

[550DarrinWI]

Thanks for posting the link to the pictures.  It looks like a lot of hard work is finally coming together for you.  I hope to be where you are at in May.  No, engine conversion for me, just a bottom up rebuild and restore. . .Make sure you post some pictures of the final product.  I'd love to hear about the work that was done to get the Mercedes to fit properly.

[Orangeman]

Anthony: Can you explain a few of the details about how you adatped the Diesel engine to the bell housing.  Sure is interesting and looks like it would be economical to run. Thanks for posting.  

[John Schwiebert]

Is that engine out of a reefer unit? Remember that transmission is only rated for 75 pound feet of torque. If you are also using the aux. transmission torque will be multiplied.!

[kp bullard]

I'm in the process of installing a Nissan gas pickup motor and transmission in my HG42.

I've kept only the tracks, transmission, and final drives.

How did you connect the diesel to the aux. transmission?

I intend to simply weld a yoke onto the Nissan output shaft. Anyone who has experience with this?

Thanks  KP

[Anthony]

John..yes i know that the torque can be a problem especially with the gearing. I am going to run her slow for a while see what happens. I saw a v8 flathead ford with 60hp but this is a diesel at 50? hp and much more torque.

The engine is from a 1967 mercedes benz 200d. I used the mercedes benz tranny as well.

The reason im not worried about the torque problem...max power is 50 hp at 4000RPM. Torque cant possibly be much above that...my ford IDI has 180hp and 330 torque. Dont know how that translates with this engine. Anyways i plan at running it at WOT then taking it to what i think is half and marking it. At idle you can let out the clutch and it wont bog the engine so i wont need higher RPM;s im thinking.

Sadly i havent got very far with it since i last posted pics....im lazzy and had to work on truck a lot and also couldnt find right size drill bits. I got myself some confidence now and am starting to work on her again.


The benz had a flex disk on it. I took it apart and welded an old cletrac ujoint on and it fit perfectly. all custom motor mounts and hydraulic pump for blade is underneath rad just barely clearing stuff. it is a belt driven one off a cherry picker. I hope it will have enough power to move the blade.....

[Blake Malkamaki]

We have the experimental tractor that was used to develop the OC-6 - it's an HG-68 with an Oliver 77 engine. It held up fine to that power. My mom used to run it and pull a 3-bottom plow.

Blake

[Anthony]

3 bottom? wow. A tractor like a farmall m is supposed to pull that. I still dont know whether the torque is ging to be a problem or not.I am leaning towards not. I dont do a lot of lugging with it and i have never had it run out of power before with the gas. It ran out of traction before power.

[Blake Malkamaki]

3 bottom? wow. A tractor like a farmall m is supposed to pull that. I still dont know whether the torque is ging to be a problem or not.I am leaning towards not. I dont do a lot of lugging with it and i have never had it run out of power before with the gas. It ran out of traction before power.

Anthony, I'm pretty sure than Benz engine does not have any more torque at the same rpms as the IXB that came out of the OC-3. It's very close in displacement and has a shorter stroke than the IXB. And unless you're running the Benz transmission in low gear with the engine screaming, I doubt you can hurt it.

These are my opinions...

Blake

[Anthony]

My thoughts echo that Blake.  Thanks for the input! The cummins has the longer stroke correct? I was always under the impression that this is what gave it all the torque it puts out.


My uncle was concerned about it going too fast. It goes slower than the ixb. A nice little puff of smoke if i rev while moving forward

Will update as progress permits. Found some old hydraulic hoses in barn so i can replace my old cracked ones. I might work on it tomorrow if its not 15* out...cold metal does wicked things to hands.

[Blake Malkamaki]

Are you running any kind of governor Anthony? I know the Benz has a speed-limiting governor and it also advances the injection timing like a gas engine does with spark, but there is no speed regulating governor as a tractor would normally have.

Anyway, I would suggest getting a belt-driven centrifugal governor such as those available as an option on a Gravely tractor. I'm sure other guys on here will have suggestions on this.

Blake

[John Schwiebert]

Well it may be feaseable to put a Bosch variable speed governor on the pump. Check with Anderson over in Grove or International in Findlay. There will be a price difference between those two. Do you have a pump and governor model? Does it have pneumatic governor? Alot of those 50 year old little imported diesel tractors did. Also that soil in your neighborhood is not that poor otherwise you not have all those speciality crop growers. Not like in western Putnam county

[Anthony]

I meant ground speed is slower but i can answer the governor questions too.

The vacuum pump sucks from 2 ways...sorta like an internal tee with the fittings on the outside of the vac. pump.


The engine has a vacuum governor i was told by a MB guru in europe.. its not pulling a vacuum on anything as it is now (besides intake manifold). It is supposed to pull a vacuum on the braking system of the old car. It does seem to rev a little high. I will fix that before i run it again. I dont know what ill do to that open port, it runs a little better if i put my finger over the vacuum line that used to go the the brakes. I might just block it off so it has good vacuum. It pulled vacuum from the brakes as well as the intake manifold. Yes John, its official name in the  pdf's i got is a pnuematic governor...am i set to go? There IS a vacuum line coming from the intake manifold to the IP itself. So I think that theres an internal governor in the ip.

I didnt know it advanced the timing by itself.  The fuel shuttof is on the pmup, it also acts as a starting aid. You pull it all the way back and it moves the rack to full load position, delivering more fuel for easier starts. BLAKE- this lever is the one that when you pull the starter switch in the cab, it lights glowplugs and pulls the lever backwards. When you push the lever in the cab "in", it moves the lever to the of position. You knew this i think.

Why do i need a governor? To adjust for loads on the engine when pushing/pulling? I always thought the only reason you have a governor is to protect against overspeed.

I didnt know you were in Putnam, John...cool! I am barely in putnam. Across our road is allen county and down the road a few miles is hancock.

[Blake Malkamaki]

Anthony,
The vacuum line that went to the brake booster can just be blocked off since you don't need vacuum for brakes. The way that is set up - the vacuum pump provides vacuum for the power brakes, since diesels don't typically develop vacuum as a gasoline engine does. However, since this engine has a butterfly in the intake manifold, it will make some vacuum while decelerating (butterfly closed). You can actually remove that vacuum pump altogether if you want. I had a plate floating around here from an older car with no power brakes that just covers the front of the governor. If I find it, I will let you know. But I may never find it as it is probably buried in junk!

The idle speed is adjusted with that cable that went into the cab. You probably know that.

I am not exactly sure how that throttle works, but I know if you open the butterfly in the manifold it will transmit a signal (either vacuum or pressure) - down that tube from the intake manifold to the injection pump - and increase engine speed. There is also linkage that goes from the throttle pedal to the manifold to the pump.

The governor on that engine is for over-reving. What would be better is a variable speed governor that will hold your rpms to whatever you want and will change the throttle position to compensate for the load - just like a typical tractor governor.

There may be an easy way to do that with this engine. John may know.

I am very happy things are going so well for you and this project.

Blake

[John Schwiebert]

If you keep the vacuum (pneumatic) governor make sure you put a drop of oil once or twice a year in the breather of the governor cover. That will help to keep the diaphram soft. Also make sure your butterfly in the intake is free to move. A drop of oil on the pivot shaft when servicing the engine is a good idea. Also get me the model of the pump. Is the pump pressure lubed or do you need to keep oil in the lower end?