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Oil in the antifreeze

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WJN

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I have a 67 Austin Healey BJ8. I discovered oil in the antifreeze several years back. Last fall we pulled the head, checked both the head and block for warpage and replaced the head gasket. Everthing looked fine. Several times this spring I drained and flushed the radiator to get any remaining oil residue in the cooling system out. As you would expect there were traces of oil. I thought the problem was solved until a few weeks ago. I drained and checked the antifreeze and this time there was was a fair amount of oil. My oil pressure is consistently 40psi during operation and my engine temp runs arount 185-190. Also, there is no antifreeze in the oil. Any idea what could be causing this problem?
 
Although someone more knowledgeable than me will be along shortly to answer this question, I am taking the opportunity to officially lament the fact that Keoke and Dave Russell are no longer sorting through this forum everyday and dispensing their wisdom with the wit and humor we know and appreciate...
 
Have you retorqued the head since you replaced the head gasket?

Are you getting any water in your crankcase?

If the answer is both yes, you may have a cracked head...

But then again I have the same problem with my cranium.

:crazyeyes:

Anyone in touch with Keoke? It would be nice to see him back here. I hope Dave Russel is doing ok.
 
oil in the water is generally indicative of head gasket woes, was the head torqued down properly?, and was the sequence of head bolt torqueing done, and was this rechecked after say 500 miles of run in?
 
My BN6 engine has got the same problem. I've changed the head gasket twice and fitted a reconditioned cylinder head to no avail. Chances are with Big Healey engines that the oil passage to the head and some waterpassages - being too close together - could crack or corrode. As a result oil would get into the water as the pressure in the oilways is higher than in the cooling system.
However, repairkits are specially designed for that. But that is a job best entrusted to a machine shop.
 
The problem you desribe is most likely "block porosity". Moss motors sells an 'oilway relair kit' that, as I understand it, was originally developed by Southern Carburetor. What they determined is that some oilways are very close to water jackets and as these motors get older and some rust/scale comes off the water jackets the natural porosity of the cast iron allows oil to seep into the water passages - oil at 40+psi vs water at 7psi = oil wins. One way of confirming is to see if you have any water in the oil, this will usually be the case with a bad gasket or crack but if it's the block porosity then it is a one way deal and you should have no water in the oil, just oil in the water.

I had this happen to a motor of mine about 6-8 years ago and I had a machine shop install an oilway repair kit. This consists of drilling out the oil galleries a bit and inserting stainless steel tubes along with a sealant. Tremendous amount of work because it requires stripping the motor down to a bare block for the machining and cleaning. Sounds good in theory but in my case it had no effect and I eventually scrapped the block.

For the last 3 years I have been dealing with it again in another block and I am unwilling to try the oilway repair again - it is very dependant on quality machining and trusting the sealant to seal. What I have found in my case is that I can go 500 miles or more without a problem and then I drain and flush with detergent a couple of times and am good to go. Cooling has not been a problem because oil will transfer heat almost as well as water. The one plus is you don't need water pump lube. Other than the mess and hassle of flushing the system, I can tell you that I have driven around 10k miles with my current motor and it runs fine. I also should note that I vintage race mine and therfore don't run antifreeze so I don't have the environmental issues of dealing with contaminated antifreeze

My suggestion is to find another block and build another motor. However, the one problem with this is I haven't found a good way to pressure test a block prior to machining and assembling so you may end up with the same problem. Pressure testing is difficult because this is a very slow seepage not an open crack.

The DMD Australia website has some pictures of a sawn open block and head and you can see how close the passages are to each other. SC Parts also has soome info in this I think, as well as Moss Motors.

Good luck
Dave Phillips
 
One of the oil passage coatings that has been around "forever" is Glyptal. It has to be applied when the engine is disassembled, but it might be a thought instead of/in addition to the Moss kit.
 
I lern sump'n new everah day! very cool.
 
Bob_Spidell said:
I was browsing a Summit Racing catalog and happened to notice they have some engine sealants, for example: https://tinyurl.com/6map9d

I have no experience at all with this type of product, but thought I'd pass this along.
Click to expand...
They do a job on your radiator too, as the particles attach to everything. I would only recommend that kind of fix to limp the car back to the barn prior to a rebuild, as it clogs up everything.
 
I've also found oil in the radiator of my BJ8. Had the head skimmed and twice retorqued. Oil still getting in there. I've been considering getting the Moss inserts, but Dave Phillips' response above makes me wonder if they're worth it. Have any other folks used them and with what results?
 
Today I was discussing the "block porosity" of my Healey engine with a reputable engine rebuilder and the best way to deal with it. According to him its either fitting an insert like the Moss kit, or to block off the oilway to the cylinderhead completely and fit an external feed to the rockershaft. Wich ever way, the engine must be stripped to bare block to deal with it.
 
Johnea:

Interesting! Hadn't thought of an external fix.

I've also been talking to a knowledgeable source. Seems the first thing to do is to confirm where the problem is. In my car, though the head was skimmed flat, the block was not - possible issue there with oil leaking past the gasket. Then, with the head skimmed, slightly higher compression results and may actually aggravate the problem. Might be addressed by using two head gaskets or going with a thicker gasket. Taking it in for compression and trickle down tests.

Question to All:

I went to the DMD Australia site Red57 mentioned above. WOW! Does anyone out there have any experience with their products? Would really like to hear more about them!
 
DMD - several Australian racers use their stuff and generally their equipment seems to result in the fastest healeys you can put on the road.

The only (very small) downside of it all are their heads and blocks are close, but not 100% original, and thus have slightly different set ups on how everything goes together.

It's all custom! When I win the lotto, I'm giving them a call.
 
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