Ok, The Mystery Continues

[dabtl]

I am going to have to whip you sonny!

 

[oddshot]

Any luck with this one yet?

Please let us know what finally fixed it.

oddshot

 

[dabtl]

I put a new head from TNJ Murray on it. It has run a couple of hours. No blown gasket and it does not appear to be making AF in the cylinders.

We will work it another couple of hours tomorrow and know more.

 

[dabtl]

I am bringing the deuce home. We THINK we may have solved the problem. We DO NOT KNOW.

I will fire it off and let it run each day next week to check it out.

Any developments will be posted.

 

[dabtl]

The truck is home. Ran it fairly hard on the way. The oil does not appear to have more AF in it. There must, of course, be some residue. The rear cylinder is not pumping AF. Maybe a cracked head was the cause.

I will keep starting and observing daily. We will figure it out.

The new head sure looks good, however.

 

[197thhhc]

Did you have the old head tested or did you just replace it. I am curious as to where the crack is.

 

[dabtl]

It was nearly as cheap to buy a new head as to test the old one.

The crack would be in the ports. We checked carefully the deck side of the head. Carefully.

 

[dabtl]

The engine has been idling for half an hour. I will turn it off at the hour mark. The oil looks good and the engine is running fine.

It may be just a cracked head. I hope.

 

[dabtl]

Cracked head it seems. All else seems OK.

I will make a pressure plate this month to detect cracked heads. If you need it, tell me.

 

[197thhhc]

I'm glad it worked out for you.

 

[jatonka]

The cost of magna fluxing can'tbe as much as a head, if it is I am going to buy a portable magnaflux tool. My boss had one at the airport when I was a teenager and we checked every head we worked on, $5 each head. for the steel powder. JT out

 

[dabtl]

The crack, if that is what it was, would have to be in the ports. After taking the head off three times, it was cheaper to just put on a new head. The problem is either the head or something in the block. I checked every post that came up on this problem. Uniformly, it was a gasket or a cracked head.

I have edited this to make some sense of my thinking. It is cheaper to put on a new head to see if it cured the problem than buying another engine and installing that if the problem is fixed. If this does not cure the problem, another engine will.

So, it either is fixed or not.

 

[Robo McDuff]

Those are the problems I really hate. Not the actual problem but not being 100% sure what it was, knowing that it was a problem that can lay low and then suddenly jump up in a few secs, ruining your engine - and your day - pretty darn quick. Logic says cracked head, but it would give me a nagging feeling not actually having seen the crack. Changing the head was a good call, I would say.

 

[dabtl]

Either it cured the problem or a new engine is in the offing. But, at least I do not have to sit around wondering any longer. Or, pulling the head off.

 

[dabtl]

The cost of magna fluxing can'tbe as much as a head, if it is I am going to buy a portable magnaflux tool. My boss had one at the airport when I was a teenager and we checked every head we worked on, $5 each head. for the steel powder. JT out

After I communicated with you and a couple of others, we went over what we had done so far.

The sequence went in this order. The oil showed a lot of AF. We had changed out the oil cooler gaskets in the Summer so it appeared to be a blown head gasket.

On removing the heads the number five piston had the metal ring blown slightly inward. I posted a pic of that gasket. We checked visually for cracks and none appeared on the surface of the head. There was no sign of cracks that we could see in the ports.

We decked the heads and reassembled the motor. Drove it a bit and had some starting problems due to a loose ground. Fixed the ground started the engine without a problem and suddenly blew the head gasket out the rear of the engine.

Removed the heads again, to make certain we had torqued properly. The number six piston gasket was entirely blown out of the back of the engine.

We then put on new head gaskets, carefully torqued them and started the engine for a short time. It did not sound good. We then removed the number six injector, turned the engine over and AF spurted out. When the head was removed the gasket was intact.

At that point the problem seemed to be at the number six piston. That is when I began wondering about the cylinder liner possibly being the source. Checked that idea out with you and it seemed remote.

Either the head was cracked internally or we had a fatal problem with the engine was our analysis. If the head was cracked, a new head would solve the problem. If not, we would need another motor. So, it was initially a lower cost to replace the head, I hope.

 

[dabtl]

I have a much higher level of confidence tonight. The engine is idling. No dripping from the radiator cap. No steam from the slobber tube. It has been idling about 15 minutes.

The oil shows signs of AF, but that is to be expected I think. The next oil change will tell the story. I will let it idle another half hour or so.

Maybe, just maybe, I guessed correctly. We shall see.

 

[hoop]

My question is, While you are getting satisfied running the engine with signs of AF in it.....what is it doing to your bearings? And why would you do that?

 

[dabtl]

I run the engine because you have to remove the AF residue. I have changed it twice. I will probably change the oil again Wednesday. Changing the oil and filters runs about $80.

I can think of no other way than to disassemble the entire engine for cleaning.

But, if you have another way, speak up.

 

[hoop]

Flush with Diesel.

 

[dabtl]

Flush with Diesel.

Thought about that. But, then you have diesel in the oil passages just as you do AF. Same result, if there is enough of either.

When I said trace I meant that there was discoloration of the oil. In the last change there was no accumulation of AF.

I am letting it sit till Wednesday to allow any AF to accumulate in the pan. If there is no accumulation the immediate problem will have been solved.