intake manifold gasket

[ryansmachone]

Is it ok to reuse the old intake manifold gasket if ita in good shape I'm putting on an aluminum manifold. Is there any epoxy I should use with this gasket. Thanks

[Mustangmike]

Personally, I would not reuse the old intake manifold gasket. Why take the chance doing the job twice. RTV silicone is what I used on my intake.

[1969jimmach]

In my opinion i would agree intake gaskets are NOT designed to be reused.

[Steven Harris]

Using an old gasket would be a stop-gap measure if you were "stuck" somewhere.

Using new gaskets and RTV will keep frustrations from leaking vacuum out of your life.

[jholmes217]

I wouldn't risk a leak by re-using a intake manifold. The gaskets don't cost that much, and it isn't that hard to do. FE 390 and 428 are just heavier and part of the intake manifold is also part of the head, so they require a little more work. Here's the steps to install an intake manifold:

1. Replace your thermostat and temperature sending units now. Use Teflon tape or paste on the threads of the sending unit. Use a 180-195 degree Robert Shaw thermostat, or get one that is made to stay open if it fails. Boil it in water with a thermometer to see what temperature it opens at to ensure it works properly. Make sure the little hole is on top. If your are changing intakes, you should use sealer on all fittings and plugs also. Also, cover the distributor hole to keep things from falling into the engine, and it may be easier if you remove the valve covers. On a big block FE engine, you have to remove the valve covers and rocker assemblies.

2. Run a tap through all the threads and make sure all your bolts are in good shape.

3. Run a couple studs down into the front and back bolt holes to act as guides for the intake manifold as you lower it. This can be done with small block Ford 260-351W, but not sure on Clevelands. This won't work on an FE, and also not sure on 385 series big block Ford. I've never built a Cleveland or 385. Test fit before putting any sealers on and start all the bolts, especially if it is a new intake and/or heads. If something isn't going to fit or tighten down correctly, find out before you put sealant/RTV on and think you are going final on assembly and then when it doesn't work, you have to buy another set of gaskets (ask me how I know!) If your heads and/or intake have never been milled (also called shaved by some,) you can probably use the cork gaskets on the front and rear of the intake if you want a factory look. If there is any doubt about them being milled, or you don't want to worry about possible leaks, use some stuff call The Right Stuff instead of the cork. Also put some RTV sealant around the coolant ports on both side of the gasket. Some like to put RTV around all ports, but that is a matter of personal preference IMO. Also, if you are going to block the exhaust heat crossover in the intake, now is the time to do that. If you don't drive the car in weather below 60 degrees, you don't need it. It hurts performance. If you drive in cold weather, leave it. Also, if it is an aluminum intake, be advised that it will eventually fail and need welded. The aluminum doesn't like the heat. Many newer aluminum performance intakes don't even have them.

4. After the test fit if everything went OK, put a very thin layer of RTV around the coolant ports, and set your gaskets down. Put more RTV on the gasket coolant port. Put your cork or Right Stuff down. Place the intake in position lightly. Use another person if its an original iron intake so you don't hurt your back (don't even think of doing it yourself with an FE iron intake without a cherry picker!) Once it is in place, start all the intake bolts (don't forget to oil them for accurate torque reading.) Once all bolts are started, take up the slack and then go through the torque sequence until you get to the proper torque on all intake bolts. Hook everything back up, but let it dry for 24 hours before you add your fluids back in.

5. This is a good time to change your oil and filter as you probably got some coolant in the oil when you took the intake off.

6. Leave the heater hose off the fitting on the intake. Add your antifreeze until it leaks out the fitting, then put your heater hose on. This helps ensure there isn't air trapped in the intake, possibly causing overheating problems. Turn your heater on, and fire it up with the radiator cap off. Watch for the thermostat to open, then add coolant as needed.

7. Tune your carb and timing, especially if this is a new combination. If you took the distributor out, check your timing anyway. For a 302, you can do an intake change or gasket change with the dizzy left in. Then drive it around to get it to operating temperature for a while.

8. Let cool overnight, then re torque all bolts again through the proper sequence. After a week, re torque them again. Keep checking for fluid and vacuum leaks.

I miss anything guys?

[noroz]

I am also about to do a manifold gasket myself and I see every one uses RTV which i know is great for doing these manifold gaskets when you just chuck out the cork peices.
But there is on thing that concerns me a little, I did my trade some 20 odd years ago in an engine machine shop, and saw way too many v8 pick up pipe screens chock full of silastic as it made its way into the oil. Thats the reason to this day I only use permatex and hylomar.
Are these silicones much more resistant than in the past or is it just a necesarry evil with these manifolds

[JTS71 Mach1]

Silicone sealants Should be used at the corners and to replace the rubber end pieces. Do not use where you have to spread them thinly otherwise as Noroz said you will have little strings of silicone finding its way into the oil, pump etc. and it will cause horrible damage if it gets any further, you simply pray to God the oil filter catches it. In my honest opinion Other then the use at places such as I stated, or an emergency. Silicone is the sign of a Lazy Mechanic! Clean the parts correctly wipe down with alcohol or carb cleaner, something that removes oil and dries quickly and a lint free towel. Then use the correct gaskets. Do the job right the first time and you won't have to do it again. JTS 71 Mach1

PS "Chevy" lovers use silicone us "Ford" boys know how to clean gasket surfaces.

[Mustangmike]

Great point and 100% accurate and very true. Silicone is very effective alternative to the manifold end gaskets which have historically been known for oil leaks. Apply it as described above and you will be fine. That is the only area on my engine that has silicone.

Great point about the Chevy guys too!!

[ryansmachone]

Thanks I will install my manifold that way and clean all surfaces. I wanna do it right I'm just broke and am so anxious to see if this thing starts....patients is a vertue haha