Head Gasket Holes

[hey_kramer]

Hey All. Would anyone be so kind as to label which holes in the Europa TCS head gasket are for oil and which ones are for coolant? I've included a picture, which I've already labeled with B's for Bolts. Please label O for Oil and C for Coolant and then repost the picture. THANKS so much!

[BDA]

I don't have a TC engine so without looking at the head, I would guess that the small holes are oil and the big ones are water. In fact, I feel pretty sure that's right but I can't confirm that.

If you have a head, maybe you could push a pipe cleaner or wire through the oil ports to the deck of the head and tell for sure.

Good luck!

[hey_kramer]

If you have a head, maybe you could push a pipe cleaner or wire through the oil ports to the deck of the head and tell for sure.

My engine is fully assembled, so I can't try the pipe cleaner trick. I just installed the gasket and had the afterthought today about which holes are which. Simply trying to satisfying my curiosity

[BDA]

I assume you haven't tried to start it yet. I would also imagine that it would only fit/look right one way but it might be worth a call to somebody who builds TCs or knows parts - Dave Bean and Ray at r.d. enterprises.

Good luck!

[LotusJoe]

I went through Miles Wilkins' book, but no luck 

[BDA]

Looking at the Parts manual, it's pretty clear that the gasket only goes one way. There are two holes that go with each cylinder that should be for pushrods when the Pinto or Cortina head is used. Those would be the ones that are part of a "bulge" at the top of the gasket in your picture. Putting that gasket on incorrectly should be pretty obvious as the pushrod part would stick out on the exhaust side of engine.

I've crudely drawn arrows on the first picture to point to where the pushrods would go if they were used.

And then I drew even more crudely drawn lines to the pushrod locations in the block. The snippet of the picture came from the parts manual.

If it doesn't look obviously wrong, it is right.

[LotusJoe]

I did find some information on a modified head gasket that relates to oil passages.


More detailed information can be found here.

http://faiauto.com/lotus-twin-cam-evolution/

[LotusJoe]

I think I stumbled onto some more information. Here is what I've been able to figure out.


Again there are a lot of pictures and information here.

http://www.wilcoxengines.co.uk/twincam%20gallery%20page/twin_cam_gallerypage.htm

[hey_kramer]

WOW LotusJoe and BDA! Thanks for the great posts! My 73 TCS is up and running fantastically after being torn apart for over 1 year. Last summer I had previously installed a new synthetic-type head gasket from RD Enterprises, but found it leaked oil and coolant profusely from, literally, everywhere. I diagnosed the problem as improper gasket sealant, but to be safe I ordered the typical "copper sandwich" style head gasket from RD Enterprises instead of the new style one again. I also used the proper sealant this time. The oil leak from the head gasket persists, from a section above the starter. The head may be warped. It runs now, quite well actually, so part of me just says to ignore the oil leak, BUT the better part of me says I should tear down again and get the head measured for warp and remachined if necessary. If I do go that route, I'm going to buy one of the FAI gaskets you posted LotusJoe.

[BDA]

Are you sure the leak isn't coming from the cylinder block breather - the rubber tube that runs from the block to the underside of the head behind the fuel pump? They can leak, be deformed during installation, etc. On the other hand, I'm not sure if you can change it without taking the head off. I think I'd heard that it can be done, but I've never built a TC and from what it looks like, it doesn't look like it.

[Bainford]

Thank you for your post, Mr Kramer. Just this past weekend I was doing a little cleaning up of the mess caused by the persistent oil leaks on my Twin Cam. As I began a cursory inspection to figure out where the oil is coming from, I wondered exactly where the oil ports were on the mating surface of the head. The worst offender seems to be the head gasket joint just above the starter. Perhaps this is an inherent problem with these engines.

As BDA mentioned, the breather tube can be an issue. I seem to have slight oil leakage here, but it doesn't seem to be the main source.

Does anyone elas have oil leaking from their Twin Cam in this area?

[Grumblebuns]

Are you sure the leak isn't coming from the cylinder block breather - the rubber tube that runs from the block to the underside of the head behind the fuel pump? They can leak, be deformed during installation, etc. On the other hand, I'm not sure if you can change it without taking the head off. I think I'd heard that it can be done, but I've never built a TC and from what it looks like, it doesn't look like it.

The head to block breather tube can be installed with the head in place. The ease of installation also depends on the hardness of the rubber tube. My replacement was relatively soft and could be bent rather easily. The super stiff ones may have to be softened in hot water.

I also installed my head gasket dry. Wilkins specifies using Wellseal for the head gasket sealant if available, dry if not. I don't have enough miles on the car to detect any oil leaks just yet.

Joji Tokumoto   


. I found that out when I replaced the head gasket on my TCS and forgot to install it before setting the head. 

[hey_kramer]

I actually have a very small bit of antifreeze leaking from the bottom seal of the breather tube. Only of minor concern to me. I checked to see if there was oil floating in the coolant reservoir, but thankfully there is no oil in there. I can say with 100% certainty that the oil leak above the starter is coming from the head gasket, as I can actually watch it slowly trickle out from about a 3-inch long section of the gasket. I'm not "glad", but rather "relieved" to see that I'm not the only one with a leak in that same area. If the block and head are indeed machine true and level, I wonder what could be at fault for causing a leak there. I think it may be due to the relatively thin amount of head gasket in that area. That oil port only has a small section of gasket between it and the outside of the engine, so sealing it adequately there may be a tricky task.

[BDA]

I'm a little surprised that a dry gasket would be advised. The MG race engines I built (when dinosaurs roamed the earth) used a similar gasket to the one in your picture - copper covered asbestos in my case, I think. That's how long ago it was! I used a Permatex spray gasket sealer that doesn't appear to be available anymore. It looks like they replaced it with "Copper Spray-a-Gasket". Of course, there are lots of other brands that do the same thing.

A three inch section that leaks sounds serious to me, but then you have to weigh the annoyance and price of oil against the bother of trying to fix it. Assuming the head and block deck were flat when the motor was assembled, could the torque sequence and values have been incorrect? How long has the engine been running? You should retorque the head after 600 to 1000 miles. The head is short enough that I don't think warping is not generally a problem. At least I don't think I've heard of it.

[jbcollier]

You mean this stuff ?:

http://www.permatex.com/products-2/product-categories/gasketing/gasket-sealants/permatex-high-tack-spray-a-gasket-sealant-detail