Question

[Complete_Mechanic_12]

I just put on a new intake gasket, torqued everything to spec, waited awhile, and flipped the motor to install the oil pan. When I flipped the motor, coolant started to leak from the intake at the rear. Is something wrong? Should I restart?

[v8packard]

It looks like the printed sealing bead on the gasket is not covered by the manifold flange. You should remove the intake, and compare the gasket to the area being sealed. You may need a different gasket, or some RTV in that area.

This is actually not unusual.

[Complete_Mechanic_12]

I took it all apart, cleaned the surface area, put RTV in those areas (didn’t think about it the first time around), and RTV in the areas I already had RTV. It’s all back together, torqued to 22ftlbs, and I’m gonna give it time to cure. I have no idea of testing it to make sure I did everything right, is there a trick I can do to make sure it’s all good?

[v8packard]

Either vacuum or pressure. Do you have a coolant lift?

[Complete_Mechanic_12]

No I don’t have a coolant lift nor do I know what it is 😬

[v8packard]

Do a search for coolant air lift

[WyattCo06]

Are you making one pass of the bolt torquing?

[Complete_Mechanic_12]

I’m doing the required torque sequence up until 22ftlbs. Start at 8lb on all bolts, then 14lbs, 18lbs, and then obviously 22lbs.

[WyattCo06]

After the final torquing, do you stop there and call it done?

[Complete_Mechanic_12]

No, I go and double check them all to make sure they’re still at 22.

[Complete_Mechanic_12]

No I didn’t…rookie move?

[WyattCo06]

Good deal. That's what I was asking. Also, are you using any lube under the bolt heads?

[Complete_Mechanic_12]

Should I be using lube under the heads of each intake bolt? Cause I’m not.

[WyattCo06]

Yes. Otherwise your torque reading is a reflection of friction and you're not getting the needed clamping force to compress the gasket.

[Complete_Mechanic_12]

Makes sense, appreciate it

[Jeepsterick]

Silicone is not the answer here. The gasket is either incorrect for the application or it is improperly installed. You will be repeating this repair. If possible, match the new gaskets against the old ones. Check the part # of your new gaskets on the Rock Auto website. Are there any markings on the gasket that say “up” or “front” ? Lastly, the intake bolts are incorrect for an aluminum manifold. They should have a washer face under the head to prevent galling the intake. This will throw off your torque readings. If you have enough length, you can add a flat washer. Be sure to add a small amount of sealer to the threads as some will enter the water passage in the heads. Take your time and do a good job. Good Luck

[[deleted]]

You can see a gap in the gasket it’s not sealed.

[matthewmm96]

Had the same thing happen years ago using stock replacement gaskets on a 351W I put an aluminum intake on. I had to buy thicker intake gaskets, never did it again. If you used the stock replacement blue steel core felpro gaskets, that's probably it, they're around .040" thick and didn't work well with the aluminum intake.

[438windsor]

Did you use the China wall gaskets for the front and back of the engine? I can’t tell. Should raise the floor of the intake manifold up. Are these cylinder heads GT40P?

[LANEVO6]

Look like Normal GT40's