Intake Manifold

[Scrubcadet10]

I'd sue you but the Texas Hammer isn't returning my calls.?

 

[djg618]

Well I did it! I took the head off the cylinder and found I did drill a small 1/16" pilot hole through to the cylinder. Yes I will clean up all the metal shavings first (Thanks). I'll clean the hole as well as the threaded hole with hexane and then acetone. Supposedly they make a JB Weld Extreme Heat that will work to patch the hole. May have to order it. I'll pack it into the hole on the cylinder side until it flares a little on the threaded side of the hole. Once cured, it should act as a plug even if it fails to adhere to the hole walls on the cylinder side. The flair should keep it from drifting into the cylinder.

Does anyone have any other ideas of products they like?

Thanks

 

[Richard Milhous]

I tried that JB Weld extreme heat stuff on an exhaust pipe and it burned right off.

 

[Richard Milhous]

and I thought this hole would be plugged with a bolt?

 

[djg618]

and I thought this hole would be plugged with a bolt?

From the outside, yes. But I thought I should fill in the hole on the cylinder side.

 

[Richard Milhous]

From the outside, yes. But I thought I should fill in the hole on the cylinder side.

What for? That space will lower your compression by like 0.00001%.

 

[djg618]

What for? That space will lower your compression by like 0.00001%.

I just thought I had to. I didn't know any better. Good to know. I'll clean up any burrs and put it back together. Thanks

 

[Richard Milhous]

Remember that when you put a bolt through there, it may push more metal particles into the combustion chamber. Also, if you can get to the rim of the hole with a rat tail file and chamfer it round, it will reduce stress and future carbon buildup. What I would worry about is, will combustion pressure pop the bolt out? I don't know what the pressure is at TDC, or how much a helicoil can hold, but that hole looks to be nearly at TDC. What's the diameter of the bolt?

 

[Scrubcadet10]

I believe the bolts are 5/16 in diameter.

 

[Richard Milhous]

Aye, there's the rub. I don't know what the compression ratio or combustion chamber pressure is, but that hole is close to the top where it will see the max pressure. At a rough guess, it will be subject to about 1000 lbs expulsive force.

A 1/4" bolt would cut this by a third. A 3/16" bolt would cut it by 2/3. Is it feasible to use a smaller bolt? If not, I think you can still get lead wool. If it's worth the price to you, pack a little lead wool into the bottom of the hole from the outside. This will reduce the pressure exposure to the diameter of the breakthrough hole.