PDA

View Full Version : TR2/3/3A TR3 Head Gasket



martx-5
02-08-2008, 12:49 PM
So, I'm ready to plop the head onto my TR3 engine rebuild. I have a Payen copper composite head gasket. Two questions...

1. There is no idicator as to which way is UP. Does it matter?
2. What is the general concensus of using any type of sealant (such as Wellseal) on the head gasket surfaces.

DNK
02-08-2008, 02:11 PM
I like to use copper sray ,but, is that redundant in your case?

Geo Hahn
02-08-2008, 02:52 PM
I do not think metallic spray is redundant as it gives a sort of soft filler layer to the copper. I just used plain old aluminum spray paint. Can't swear it helps but have not had a problem.

Also, I do not know that it matters which side is up. I suspect not as I recall they are punched to work either way. That said, I always put the side that has the folded-over edge facing down.

Moseso
02-08-2008, 05:18 PM
When I took mine apart -- head gasket leakage was not the problem -- I could detect no sealants at all and the folded-over-edge side was down. I intend to put the new one in the same way.

PeterK
02-08-2008, 06:57 PM
I think originally, they were fitted bare.

But I used the copper spray meant for head gaskets. You have to let it sit before putting the gasket on otherwise it just squirts out. Its purpose is to seal up any small imperfections between the surfaces so I think it's a good idea to get a good seal.

Banjo
02-08-2008, 10:26 PM
I use coppercoat spray. follow the directions carefully. folded side down (not sure if it matters) And be sure to re-torque the headbolts after a good warmup/cooldown cycle or two.

TR3driver
02-12-2008, 08:52 PM
Book says to use Wellseal "or equivalent".

My experience has been that if everything else is right, it will seal just fine with or without your choice of sealant. But if something else is wrong, like distorted studs or (as in my case), not enough liner protrusion, then NOTHING is going to make it seal. Copper stuff, silver stuff, genuine Wellseal (brought in from the UK at great expense), Permatex #3, none of them made any difference whatsoever. Best I can tell, the block was improperly machined at the factory, because the liner protrusion is within spec on one side (the side I checked over and over again, naturally) but they are low on the other side.

Head gasket will fit & work either way (some very early gaskets didn't have the redundant oil hole but I think everything since about 1960 has had it). However I've read a line somewhere to put the smooth side down, which makes sense to me. Otherwise, one of the crimped seams hangs out into the water jacket and seems to open up slightly when the head is torqued down.

TFR
02-14-2008, 08:40 AM
Cooper head gasket spray from Loctite works very well. Use it on my very high compression (18-1) motorcycle race engines.

Moseso
02-14-2008, 02:10 PM
Has anyone here tried the solid copper head gasket like the one from Gasket Works (https://www.headgasket.com/)?

Any comments?

sp53
02-14-2008, 05:33 PM
I never used to use any gasket treatment on a head gasket, but on last tr3 engine I rebuilt there was a problem on the lifter side of the engine. It stated to leak oil right above where the coil bolts on. The head gasket sealed ok for compression and water separation. This oil leak is just oil pressure and something I have never experienced. I purchased the vehicle as a non-runner so I was unfamiliar with its condition. I used new pistons and liners and everything stuck up fine, but this little oil leak is really disappointing. My machinist friend said I should have painted the gasket with silver spray paint, but I put it together dry. If I had it to do over again, I would have looked over the surfaces better on that little strip of cast iron in the lifter gallery, and painted the gasket with something specially designed for head gaskets if there is such a thing. I am going to retoque the head, but the same machinist did not have much hope for me there. He suggested cleaning the seam between the two squeaky clean and to try sealing that section from the outside, but he did not have a lot of hope for that either, but maybe. I have not ran the engine much (maybe an hour or two) and the leak is very slight. The cause is perhaps a small scratch on that thin edge of the casing on the outside of the lifter gallery. The right fix is probably pulling the head off and taking a look, butttttt
Sp53

Geo Hahn
02-14-2008, 06:03 PM
...It stated to leak oil right above where the coil bolts on...

Are you sure that is where the leak is coming from? You probably know the but in case you do not... the bolts for the coil bracket go directly into the oil galley and can leak if they do not seal well.

TR3driver
02-14-2008, 08:05 PM
If that is where the leak is coming from, there is no pressure at all behind it. So IMO you have a good chance of sealing it by cleaning very well and buttering the outside with RTV. Let it cure for several days before starting.

However, I doubt a "small scratch" would cause a problem. Since there is no pressure against it and the head gasket does have a considerable amount of 'crush', it would have to be a pretty major gouge to leak there.

Another possibility is a pushrod tube leaking ... a relatively common problem and irritating to fix.

sp53
02-16-2008, 07:50 PM
Thanks for your comment Geo and yes I am familiar with the coil bracket holes and I looked at that first. The leak appears more like oil dampness and not a drip. It appears on that little edge where the block and the head meet. But Randall why would there not be any oil pressure in there? I hope you right because it would perhaps offer some hope for a seal, but isnít the whole oil system under the same pressure? I have not worked on the engine all winter and I plan to start soon and then I will get some pics. I spent my winter car time getting a Saab running for my son. And thanks again gentlemen for you help; I respect your opinions very much.
Thanks
Sp53

TR3driver
02-16-2008, 08:17 PM
But Randall why would there not be any oil pressure in there? The headgasket above the coil is only sealing the space where the pushrods run; which communicates with the crankcase. The oil from the rockers runs down through that space, but there should be essentially no pressure (less than 1 psi) unless your crankcase breather is blocked.

The only place the head gasket sees oil under pressure is a small (like 3/16") passage near the back, where the oil from the rear cam bearing goes up to the rocker shaft. And even there, the pressure is far lower than what's shown on the gauge, only a few psi at most. The high pressure oil runs only through the cylinder block (and crankshaft, filter head, bearings, etc.)

Randall

sp53
02-17-2008, 06:48 PM
I guess I see what you mean Randall. I never thought of it that way and that helps explain the open crank chase ventilation system better. I often wondered how such a large hole in the block with a breather would not let more oil out. Do you think the new rebuild could have more crank case pressure also?
Steve

TR3driver
02-18-2008, 12:31 PM
Do you think the new rebuild could have more crank case pressure also? It's possible, but usually a freshly rebuilt engine will have less pressure rather than more. The pressure comes from combustion gases leaking past the rings and a fresh engine should have minimal leakage. The stock TR3 engine had a generous open breather tube, so pressure is minimal even with significant blowby. However the later TR4 and 4A configurations had much smaller breathers and so were more apt to build crankcase pressure (mostly with a well-worn engine being operated at full throttle).

Are you sure the oil isn't running down from a leaking pushrod tube, and then back along the edge of the headgasket ?

Bill
02-19-2008, 11:44 AM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:] The stock TR3 engine had a generous open breather tube [/QUOTE]
This is a nice way of saying that a TR3 is going to leak oil in your garage after you drive it, but you shouldn't need to worry about rust on the driver side floor pan comming up from the bottom side because it is liberaly coated with oil from that breather tube. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif