Timing Chain Cover Gasket

[LAW75]

Hi friends. Have a '66 AH 3000 BJ8 Phase 2. I need to try to correct my perceived cause of an oil leak, coming from the gasket seal on the timing chain cover. From a look, it appears ? that to make this repair, I have to remove the radiator, fan and pulley connects to get to all the nuts on the cover. Is that so? Any short cut tips (to avoid all the other disconnects) on the process? Thanks, as usual, for your help.

 

[Bob_Spidell]

I've done this on my BJ8. Yes, you have to pull the radiator, fan, etc. The big nut on the crank pulley can (will) be a bear to get off, I bought a HF 3/4" air impact wrench to do it (my DeWalt 18V 1/2" battery impact wrench is probably just as powerful, if not more so, but I didn't have it back in the day). Anything else will just rotate the engine, but others on this forum have reported techniques for locking the flywheel). I don't recall the nut size--1&11/16" comes to mind, but I'm not sure--but it's a big, usually hard-to-find one (I've never seen an impact socket in the size, but that was before Amazon). To get an impact wrench on the nut you'll probably need to raise the engine a couple inches to clear the chassis cross rail (Note: You might be able to get a socket and breaker bar on the nut without raising the engine, but I'm sure if I could I would have done so; I think the pulley might not clear anyway). It's easiest--easiest being a relative term--to unbolt the mounts at the frame; if possible, get some really long bolts--IIRC they're 3/8" fine/24 used everywhere on Healeys--and replace the 'stock' bolts one at a time with the long ones else getting the mount lined-up again can be a, well, bear (but doable). Two on each side should do it. You'll need to disconnect the tie rod on the tail end of O/D to raise the engine, and the throttle linkage lest you break or bend something. Be careful not to raise the engine so high it bends the throttle cross-shaft in the scuttle/firewall where the gearbox passes through. Put wood or other platform on your jack to spread the load on your pan; I've replaced it since, but for a while my car's pan had a perfect imprint of a 2x4 on the pan.

You'll want to replace the seal on the cover, of course, and when you get ready to bolt it up be sure to center it properly--let it find its 'home'--on the nose of the crank, there's enough slop in the bolt holes, then tighten the bolts carefully (don't overtighten lest you bend the sheet metal). Put a little grease on the seal lip so it doesn't wear on startup. BCS sells a 'strap' that connects all the bolts that should, in theory--I haven't used one--spread the tension around the edge of the cover and mitigate leaking. I usually use a thin smear of Permatex Aviation Form-A-Gasket on paper gaskets, it stays somewhat pliable and on occasion I've been able to peel a gasket off whole (theoretically, you could reuse it, but I don't). Lately, a lot of paper gaskets I've bought don't fit perfectly, so modify it if necessary and I usually buy at least two since the cost isn't as great as the time wasted ordering another.

 

[gonzo]

Also, check for a wear-groove on the Harmonic Balancer pulley shaft. This is from many years of the shaft spinning in the cover seal. A stainless steel "Ready-sleeve" or Spedi-Sleeve will repair the groove and provide a smooth and leak-free seal once installed.

 

[LAW75]

Thanks Bob for the "wonderful" news. Sounds like a $10 gasket to replace will cost (if sent to a mechanic) $500+! Eeek. Maybe I'll just put some bubble gum around the union of the cover...

 

[roscoe]

I have removed a crankshaft nut by putting thin rope into a cylinder through the spark plug hole with the piston at BDC and raising it until the piston is locked on a compression stroke and then used a smooth jawed Ford wrench with a bodacious long breaker bar. All for want of an impact gun. The Ford wrench conveniently avoided any clearance issues.

 

[gonzo]

So that's what they're called: Ford Wrench. I have two of them same size. I like to use them for the oil drain plug. Now I'll train Bowser "Get Ford Wrench, Bowser" "No, No, the other Ford Wrench...good boy, sit."

 

[steveg]

Bowser rings a bell: Jack Warden to Toby the Beagle in Used Cars: "No Toby, the Phillips screwdriver."

 

[steveg]

I installed the BCS timing housing reinforcement plate. It was still pretty thin, so I used it as a template to make an additional plate from 1/8" flat steel from the hardware store. Stacked them both on for additional strength. The lower bolts are widely spaced. Russ Thompson told me he inserts additional bolts between them if he has the front engine plate off.

 

[Bob_Spidell]

What would be ideal would be a cast aluminum timing chain cover, similar to the cast sump pans. I think there'd be enough clearance behind the pulley and/or damper. I know, I know 'not a big market,' but one for 4-cyls and one for 6-cyls might be enough (we can get cast valve covers after all).

 

[Healey Nut]

Why not have someone manufacture a large washer say 1/8” thick in the shape of the timing cover that would fit into the recessed area where the bolts are so it would act as a compression plate on the cover and subsequently the gasket . These could be easily water jetted by someone ?

 

[Healey Nut]

I think most timing cover leaks occur because people over tighten the bolts and deform the cover . They are only 1/4” fasteners and it’s not like the timing cover is under great pressure when running .
All I ever use is a paper gasket and Hylomar (blue) if it’s good enough for Rolls Royce then that’s good for me .

 

[tahoe healey]

British Car Specialist sells a reinforcing plate that fits on to the cover and aids in a better seal and uses the bolts to tighten the timing cover and prevents the over tightening warping. I did it with out removing anything but the bolts on the cover. Not fun or easy but is seems to have eliminated the leak almost completely ( so far) from that area.

 

[dougie]

I think most timing cover leaks occur because people over tighten the bolts and deform the cover . They are only 1/4” fasteners and it’s not like the timing cover is under great pressure when running .
All I ever use is a paper gasket and Hylomar (blue) if it’s good enough for Rolls Royce then that’s good for me .

Ditto -

I've had my race motor torn down and re-build more times they I'like to count and never a leak from the timing cover. When I saw this "new" timing housing timing housing reinforcement plate I had to laugh.....Just more weight I didn't want on the front of my car.