Leaky Head

[LTD1963]

I have read a lot of posts about bad head gaskets and coolant consumption. Many of them involved cracked cylinders and other bad things.
I was wondering if that is where I might be headed. Here is the symptom. On the drivers side,
OIL seems to be leaking from the rear of the head. I think it is the head gasket because I do not feel any oil above the gastet but alot below.
I dont seem to be looseing coolant though or if I am not very fast like the other posts seem to. I was wondering if anyone noticed a OIL leak from there head gasket before the coolant loss? I am going to do the phaser gears in a couple of months and plan on replacing the head gastet at that time. Anyone see a problem with this idea or should I just take the head off now and see what I find?

[AndyL]

There are no oil passages from the head to the block or between the head gasket. If you are leaking oil I would check the valve cover or possibly the oil pressure sender if it is leaking on the back side.

Replacing the head gaskets is a big job, I don't think I would do it unless necessary.

[charliepeterson]

Sometimes if you have a small fuel leak at the filter housing or Injection pump it leaks into the valley between the heads. From the heat or dirt in the valley by the time it makes its way to the back of the heads it looks like an oil leak in color. This will drip towards the transmission bell housing or the back of the heads. You might not notice the fuel smell but the consistency will be light like fuel oil.

If the oil level in the crankcase doesn't drop and the truck is running good I wouldn't go looking for extra work yet. Don't worry, we all seem to have our turn spinning wrenches at one time or another.

[LTD1963]

I like both of your suggestions. I guess it could be diesel from under the filter or oil from the pressure sender. I will look into these ASAP. I do have a question though. If there are no oil passages from the block to the head, how do the springs and rockers get oiled under the valve cover? Ive tried my best to figure out where the oil starts and stops with the intake and fuel filter and stuff still on but I guess Ill need to take them off to make sure. Not much room back there. Im pretty sure though that the oil is not comming from the valve cover as the oil seems to be on the block just under where the head attaches and not on the head. As for the loss of oil I can not be sure because part of the reason I am doing the phazer gears is because I have another leak comming from the front oil seal. Thanks

[AndyL]

The oil gets to the top of the engine via the pushrods, same as a gasser.

[TAG]

Don't these engines have the oil pump drive where the distributor would be on a gas engine? If it does & the o-ring is leaking i think you would see the leak path around the rear of the head gaskets.

[AndyL]

Originally posted by TAG:
Don't these engines have the oil pump drive where the distributor would be on a gas engine? If it does & the o-ring is leaking i think you would see the leak path around the rear of the head gaskets. These "plugs" almost never leak on the 6.5s, but possible I suppose!

[LTD1963]

You guys are great. Saved me alot of worry.
I took off the bolts to the fuel filter so I could get my hand back there to find where the leak started. I found out that the oil pressure sending unit threads into a fitting that goes into the block. I believe that the oil was coming from where the fitting threads into the block. Took it off and put some thread sealant on it. We will see in a few days if that was the culprit. Thanks again.