Engine and Transmission Tech

To assemble my new Edelbrock 2198 intake manifold to my old Rover 3.5L aluminum engine, I am using stainless hex head bolts and flat washers. Should I also use lock washers? If yes, what kind? Star, split or bellville? Also what kind of thread sealant is recommended?

I would NOT use any sort of lock washers.

I use more stainless steel fasteners than I used to, but I don't like their tendency to gall.

I wouldn't use thread sealant. Instead, I would generously apply anti-seize to the bolt threads.

IMHO, the intake manifold bolts should be tightened by hand, with a torque wrench, incrementally, in a pattern that evenly clamps the gasket and evenly stresses the intake manifold flanges. In my youth, I did this wrong and I cracked my Buick 215 4bbl intake manifold. (I had to have the crack repaired by a welder.)

Cadillac 4.5/4.9 used conical washers and low torque because of iron heads and aluminum intake. The difference in expansion when hot is about twice as much for aluminum. Under 200 degrees it is about the same. What happens is the intake gasket compresses and then leaks when cooled down. The conical washers work kind of like springs. The 2.8/3.4 GM V6 guys or actually any iron head with aluminum intake that runs hot(emissions) should do the same or recheck the intake torque frequently to prevent intake gasket leaks.

Curtis,

Great insight and thanks for sharing the cracked intake experience from "your youth". So I'll stick with flat washers and my own 63 years of persistent youth. Then I'll find some anti-seize that likes both aluminum and stainless and use my torque wrench to sequentially tighten to the 28 foot pounds in the Rover spec.

Springs tend to go flat when subjected to high temperatures. If you've ever run lockwashers on the exhaust you've seen that. On the I-H SV engines I went as far as fitting long bolts, alternating flat and lock washers in a stack to create a finned radiator and followed with a high temperature heavy exhaust flange spring to maintain clamping pressure. It worked but the stack was about 2-1/2" long.

Rover has some very nice MLS exhaust gaskets made from stainless with a double beaded seal around the port. They cost about $40 each (x4) but the bead does not collapse and they are reusable indefinitely. This is the proper solution. However, they do not match the 300 port. I have found a solution, however it requires some trickery.

First is to find some steel or stainless wire of a proper size to re-form the bead around and make a box of the proper size to fit the port and seal properly. Welding the ends together and smoothing the joint is helpful. Next slip that inside the layers of the gasket and position it correctly. Then press the gasket between two rounds of hard plastic such as nylon with a hydraulic press to reshape the bead. Then if you feel it is necessary you can trim the inside edge to match the port. I didn't. This gives you a MLS stainless gasket to match the 300 port and should end your difficulties.

Jim

I thought we were bolting down an Intake manifold? ;)

I used these on my Camaro. Came with stainless washers. Add a dab of anti-seize & torque down by hand evenly in proper sequence. Y'all really use a torque wrench for 28 ft-lbs?

[www.amazon.com]

Wrong thread I guess.

Good info. I hope you find where you meant to post it.

Yep,
I use a torque wrench for everything!
You get canned in my shop if you don't.

I confess,I even have a little one that reads in inch lbs! Stops me from breaking the smaller fasteners.

Always wanted a smaller torque wrench for inch-lbs. Just torque by hand til I feel the stretch. :)

Impossible to use a torque wrench on the exhaust header bolts on my installation. Most of the bolts can only be accessed with an open end wrench. According to Sanderson Headers installation instructions, you pull on the wrench until your knuckles turn white - at that point you've reached the correct torque. My question is - is that my knuckles or "Bubba's" knuckles.

[www.sandersonheaders.com]

This is why the "crows' foot",is useful. Under Bubas redneck solutions: "I never use (inch/lbs),jus' grab the tork wrench 12" shorter". roverman.

I find my own sense of torque alarmingly precise so I use my torque wrench only annually to calibrate myself.