Oh NO! Engine Problems

[Bill_Wolf]

Just before winter found no compression in #3 cylinder.





I finally got the head off in this nicer weather and found a burned valve.

I also found what looks like woodstove cement on the valve surface under the pictured carbon residue. This actually explains a lot.

When I bought my CCKW I purchased it sight unseen (BIG MISTAKE!). The agreement was that I would hold back some of the total until I was satisfied with the condition.

When it arrived it would not run as the fuel was crappy and the tank was loaded with crud.

To check the engine condition I was able to check compression, spark, dwell, etc and did so. Compression in all cylinders was between 125 and 130 psi.

I got the engine running and was able to run it and extended idle it. I could not drive the truck or stress test the motor as there were no brakes and it could be driven on the road.

While going to put it on the road last fall a miss developed. An infrared thermometer indicated substandard temperature from the #3 cylinder. A compression check revealed 0 compression and a leak down test sent air directly to the exhaust system.

Strange that it would be fine for so many years and then have valve problems so quickly...but it happens.

Upon disassembly I also found that the manifold gasket was for a 302 and not a 270. I also now have a valve here whose surface is covered in woodstove cement. Did the previous owner "patch" the valve to quick close the burn so he could quickly sell the truck with a bad motor to an unsuspecting buyer. One will never know.

Where can valves be purchased.

Bill

[Hammerhead]

Hey Bill,
Sorry about your bad findings. Have you checked with Kevin Kronlund? Perhaps he would have what you need or know of someone who did. Good luck.

[Degsy]

Hi Bill, sorry to hear of your problems, if you can't source the parts you need in the US they are available from Rex Ward in England www.dukwparts.com orWildenberg Holland www.wildenbergparts.com
Be careful with the manifold gasket, make sure you get one of the copper 'sandwich' type, there is a lot of cheap rubbish available.

[42cckw]

Hi BILL
Sorry to hear about your misfortune , looks like you may have been hoodwinked The last catalogue I have from Frank von Rosenstiel shows he had Intake and Exhaust valves, you may want to give him a call good luck !
JIM.

[Cat Man]

Hi Bill,

This is were the engine guy has to jump in!

A couple of ideas before you complete the cylinder head repair. In today's work of high service labor rates, mechanics don't get paid to diagnose much, but rather to quickly replace damaged components with a factory remanufactured or rebuilt assembly. The result is the technician and the customer / owner never really know what caused the failure.

The 1940's and 50's era shop manuals have lots of good information about diagnosing the cause of valve failures. The broken parts always tell you a story if you read the parts.

I went back and looked up a couple sources on gasoline engine valves (I'm a diesel guy remember)

Valve failures similar to your photo are usually the result of one of three conditions

Insufficient valve clearance - can't check that since the head is already off. A likely cause in this case since only the # 3 Exhaust valve has failed.
That reinforces the need to check and adjust valve clearance more often.

Valve overheating - If there is a blocked or obstructed coolant passage near the vavle, it will run to higher temperature and result in a failure. IN the photo, the coolant passage nearest the damaged valve is about 75% blocked. Cooling system maintanence required and use of the correct gaskets.

Third item to inspect is valve stem condition. A valve sticking in the guide results from gum build up. That can be cold operation and long storage peroids (Winter), resulting in rust on the guides. The valve doesn't close correctly and will fail. You would expect to see evidence of that on more than one valve stem.

Those areas should be inspected and corrected to avoid a repeat failure after the cylinder head is repaired.

That's the short version, but it should help you with the "inspect'in and detect'in.

Valve adjustment, coolings system maintanence, better modern lube oil formulas are all important. I don't thint anyone tried to "patch" anything, it was just time under the operating conditions.

My 2 cents.

Cat Man

[John V Cliche]

I agree with Cat Man
Lack of PM ( aka proper service WITH proper parts ) is most likely the culprit
Pull the engine, and do a complete overhaul while your at it, and know you will be problem free

Hope this helps
John

[Bill_Wolf]

Thanks for the tips guys...

On another site Joel has stated that he was aware of this truck and its problems through 3 previous owners confirming that I got deliberately suckered by the previous owner.

I have asked him to kindly provide me with what he knows as additional diagnostic input.

As far as pulling the motor. I don't have the money to do that. It will just have to wait for the budget to stabilize. I know it is short sighted but a band aid is all that is going to happen now.

Don't the crooks in this hobby just suck!

[John V Cliche]

What about the head from the 352 ?
Is it servicable ?

John

[Bill_Wolf]

John,

The condition of that engine is unknown.

That one will stay the way it is.

Bill

[Cat Man]

Bill,

Repairing the cylinder head with a new exhaust seat and exhaust valve is certainly what's required. I'd spend the money to at least disassemble the other valves and inspect them. They will benifit from grinding valve faces and seats. Then put it back together and drive it!

Complete overhaul doesn't seem to be necessary if the goal to to get it to a few shows a year.

In our engine busness, when we do planned service on undamaged running engines, we often do what is refered to as a "Top End" overhaul which is valves, seats, head gaskets and turbos, then at the second "Top End" we install new Main and Conn Rod bearing s awell as a Lower End Overhaul. A true "Major" overhaul is done on the third time around.

Just fix what's broke and drive it.

Cat Man

[Gordon_M]

I've seen engines in this condition, and while it all may repair properly given time and budget I'd certainly go with fitting another head, having given it a good check over first.

The army wouldn't fix that, just swap on another one and put the old unit in the rebuild pile. I remember one CCKW owner here that took a spare built up head with him every time he took the truck out, and had a complete spare 270 at home.

I wouldn't put that one back unless it had been stripped and checked for cracks, especially in the valve seating areas, and I'd be crack-checking the top face of the cylinder block too.

A crack, even a big one, isn't the end of the world, but it does need fixed properly. One of my 270s had a crack all the way from the bottom centre left of the water jacket back through to the bellhousing, and after a proper keyed reapir it is still around four owners later.