The GMC CCKW

Lord, I am going to get lynched for this. I have a CCKW that I want to replace the 270 gasser with a multi fuel. Has anyone heard of this? I have a line on the motor, but I don't know if it will bolt up or not. Any suggestions would be appreciated.

The "lynchin' party" already left the barn

Seriously if you want a multifuel in a 6x6 get an M35A1 or A2
If you try to put it into a CCKW your gonna have..... weight issues...,width issues,.... lenght issues,.... cooling issues,.. oh and don't forget gear cases and drive line issues....and IF you get it going ...remember you're gonna have to "stop "it sooner or later

Hope this helps
John

Why not seeking out an already converted GMC? After the war Henschel in Germany took many surplus GMC trucks and replaced the engine with its own manufactured Diesel engines.



The advert reads:

GMC-TRUCKS
for 3 1/2 to and 5 to payload
economical with
HENSCHEL
DIESEL-ENGINES


Regards,

Chris

The multifuel is Waaaay too long for the bonnet of the CCKW. Do you remember seeing the pix of the post-war prototype with the 302 gasser and the auto tranny where they had to push the radiator out the front...?

Chris,

I was thinking about the Henschel repowers. That is a very cool postwar ad. Does anyone have a picture of an actual installation or Henschel engine? It would be fun to see one.

As for repowering a stock CCKW. BAD IDEA.

The local Cummins dealer here tried it in the Wisconsin Dells Duck Tour DUKWs with a 6B or C6 model Cummins. The transmissions, transfer box and drive shafts all parted company when asked to accept the higher torque of the modern diesel. The DUKW's are now back to swiming with the stock 270 gas engine as God and GM intended.

Cat Man

Unfortunately I was not able to find any picture of these engines. The only facts I found out, they were called Henschel Lanova. Already developed in the early 30ies. There were 4, 6 and 8 Cylinder Variants.

Well, That answeres my question. Maybe a full teardown on the 270 would be appropriate. I just need the extra torque for snow plowing. I dont take it very far from the house, so speed isnt my concern. Just pushing power. But then again, I dont have the money to replace the entire drivetrain, so the multifuel is out.

How fast are you trying to plow?

You have all the torque you need with all those gears behind that motor.

I plow snow with my 42 Chev Army truck with a 9 ft plow and 7.5 ft wing. It has all the power I need and torque I need with the 235 six in it. I don't plow at break neck speeds, usually using 1st or 2nd in high range so that I have time to react instead of getting stuck or maybe breaking something.

If you are trying to plow at highway speeds, get something different....

I am just trying to plow my 1.5 mile driveway and parking area. Its not the speed, it is the pushing power. I get a lot of snow, and it piles up quick. (It is laying at about 4.5 ft right now) the 270 just runs out of power, but since it is smoking terribly, I think a rebuild is in order. I imagine that the 270 will have the power I need if it was running at 100%. I just hate working on it during winter, so I guess I know what my summer project is And the plow weighs about 2100 lbs and is a 10 footer. Do you know of any full rebuild kits for that 270? Main bearings and gaskets and the whole works? Thanks very much. It is really enjoyable talking to everyone about these cool old rigs.

The short answer is No one has a complete overhaul set.
The long answer is most items are out there but some leg work may be involved
Joel Gopan on this site probably still has a fair amount of power train stuff
Frank von Rosenstiel in Ontario has also ( he adverts in MVM and Supply line)
Sam Winer advrts gasket sets
NAPA has been pretty good also for some stuff.
Hemmings motor news in the parts sections may help you with pistons and stuff including Bearings
EGGE Machine in Ca can and will custom make most anything you can't locate. ( at a price ) including sizing bearings
But until you have torn it down and checked all you journals and bores for condition and SIZE you won't know what you need.
This would be a good time to do the head with new valves and hardened seats also.
Hope this helps
John

Very helpful. I have been able to locate some of the rebuild parts already, so it doesn't appear to be too difficult. All it takes is money I suppose. With the hardened valve guides, do I have to run leaded gas or can I just run pump gas? Also is 87 octane fine or should I upgrade to a higher octane. Also, I am running an aftermarket electric fuel pump, and that doesn't seem to work very well, so can I rebuild the fuel pump, or should I just replace it? Thanks again.

It isn't hardened valve guides, it's hardened valve seats.you can run pump gas.But given your intended use of little to no highway use the risk of burning valves will be less anyway.These engines are LOW compression so the lower octane will be fine ( you will tune the engine to the fuel your using anyway)
Be careful with the electric pump some will over power the needle and seat ass. in the carb.
Frank von R has rebuild kits for both the 2 valve and the 6 valve fuel pumps It is a simple and straight forward rebuild
Do you have a pump with the original priming lever?
Time to get Manuals also

Cheers
John

Another option to get the original fuel pump redone to spec is to contact John Bizal at Midwest Military, Inc. www.midwestmil.com. He is in Minnesota.

John does lots of Dodge stuff. High quality. The internal check valves and diaphram on the late CCKW 6 valve pumps are similar to the Dodge. John has the correct pump parts and a special set of fixtures to disassemble and CORRECTLY reassemble the rebuilt pump.

He rebuilt my CCKW pump while I watched. Showed me the difference in the poor quality import kits. He does not use them. He really knows how and can do it faster and with better parts than I could fool around with it myself.

You will definatly want the original style pump with the hand primer. That primer makes a world of difference when starting up after the truck sits for a week or two.

Cat Man

Not sure what your pump problem is. All mine have electrics with no problems. Make sure you have a filter BEFORE the pump. If you will be letting the truck sit for long periods of time, the electric is the way to go.

Patrick's in AZ also has engine parts along with Jim Carter

Bill Wolf: We should have a more up to date and complete page off of the HOME page for vendors who have parts for GMC's and Chevys and what they carry

dr deuce wrote: We should have a more up to date and complete page off of the HOME page for vendors who have parts for GMC's and Chevys and what they carry

Good idea!

That would be fine.... everyone send me a list of who they are (with their email address) and what they carry.

No posting of any businesses without specifics and part numbers

Sorry to add to this but as Dr Deuce says its all about reliability and long runs on motorways towing with the 270 when it is nearly at max revs is not so desirable. So what is the thoughts on a Diesel Cummins 4BT engine how would this compare to the standard gas 270 or the common 302 conversions, the reason I say I would consider a Diesel in my GMC is that over here in the U.K. petrol ( gas ) is now up at £5.36 for a UK Gallon ( 4.5 Litres ) so as I travel quite alot with my truck with it loaded and towing a 105 Howitzer 2.25 tons this might be a consideration.

I´m installing diesel to my G506 project...... Because fuel prices are high in Finland too ( 95 is 1.4€/L and Diesel 1.10€/L)

I just made adapter plate for Chevy bellhousing and Toyota H-motor (3.6L Diesel)
Same adapter plate should fit to Toyota 2H and 12HT motors too.
I still need to machine an adapter to match Chevy flywheel to Toyota crankshaft.

Hi, the engine looks like a good fit, nice that the exhaust comes out the same side as the original one, have you been on the www.HMVF.co.uk good active forum in the UK lots of helpful people on there and on here.
Does the engine fit at the front of the chassis, is it about the same length as the original engine. Keep us posted on the progress.

Engine is 2 inches longer than Chevy 235, But there is still enough room for radiator. Stock front engine mount won´t work in this swap, oil pan is too close to it. I´ll make new side mounts which are bolted to frame or front crossmember.
I´m not yet registered to HMVF....... maybe someday i will

Good thing in those 6 cyl Toyota engines are that they make max power in 3500 rpm, So 80 km/h with stock gearing is possible.....with ear plugs
http://en.wikipedia.org/wiki/Toyota_H_engine

Flywheel adapter is now ready........ Here is video from starting with 6 volt starter and 12v battery:

http://www.youtube.com/watch?v=B-I0cLAMFDw