waterzap

Ok. So I installed a new intake manifold gasket on my 67 Toronado. However I used the little rubber ends. And of course they came out. And of course now the car runs like crap. Runs ok, idles terrible. Need to do it again, this time use RTV, but for the life of me I just cannot, cannot get the manifold loose again. Its stuck. Last time I just tapped underneath the manifold a bit with a socket extension and hammer, and off it came. Coolant is drained, distributor is out, bolts are out. Manifold just sits there.

oldcutlass

Just gently pry it up. Have your heads been milled?

rjohnson442

long block of wood and a "BFH" Tap harder

waterzap

Tap harder. I guess thats what will have to do. Was also thinking of getting long block of wood, see if I can catch the lip of the manifold, and put a jack under the block. Tried lifting it up by using the timing cover as a fulcrum point. Didnt try VERY hard, but didnt work.

NDERISE

make sure all 12 bolts arte out try to push the front rubber between the bock and intake inward at a corner were u can insert a screwdriver and pull up with a slow gradual continues force
ray

waterzap

You know what. That just gave me an idea. I did get the rubber out. How about a thin wooden wedge? Long flat wedge? That should not hurt anything?

cjsdad

Did you put gasket sealer on it last time? That is a lot of surface area sealer to overcome if you did. Is it the cast iron intake or aluminum? If you have verified all the bolts are out, the wooden wedge sounds like a good idea. Just be sure to clean out any shavings that may come off.

waterzap

I did a very good job last time. Except the rubber pieces that came off in the corners. Yes, I put gasket sealer on. Oh well.....
Its all cast iron. Block. Manifold. Probably weights 60 lbs or more. Will just put a wedge in, in the corner. If the one side lifts, thats all I need.

cjsdad

Like I said, that is a lot of surface area that is glued together to overcome. you will basically be pulling the intake gaskets apart so go slow and steady with the wedge. It should work. Once you start with the wedge you may need to start the gasket separating by poking a scraper along the upper edge of the manifold. Once the gasket starts splitting you will be golden, except for the clean-up.

Fun71

Yeah, those heavy iron intakes are hard enough to get off without them being glued on.

MDchanic

Pry bar (preferably one of the fancy ones that's like a giant screwdriver with a bent end, but a crowbar will do).
Stick it in where the rubber gasket was and just pry it off.

- Eric

Professur

Check your local auto ***** store for a brass scraper. You can give it a more than firm hit and no worries about it damaging the faces ... or causing a spark for that matter. No good for prying, but you can dig into the sealant and cut it loose without worry.

tecar442

I would use The Right Stuff. IMO superior to regular RTV. It should be in the same place as the RTV in your auto parts store.

MDchanic

No need to worry about the sealing surfaces on the front and back - in fact, many people intentionally "texturize" these with a sledge and a punch before sealing with RTV.

- Eric

seansolds

I used a chisel on both corners, between intake and block where the rubber used to be closest to the cylinder head..use the chisel as a wedge and tapped on it with a hammer until it is loose.. Mine is aluminum..you won't hurt the cast.

waterzap

Got the stupid thing off. Managed to get the rubber edge pieces out. Then with a small screwdriver, on the edges, tapped the screwdriver in enough to get lift on the edges.
So my question is now. How do I do this correctly for the next time? I don’t want to do this again? I guess all the ports were fine and sealed. Just the rubber on the edges moved away.

MDchanic

Clean and degrease the sealing surfaces well, apply a bead of black RTV sealant where the rubber strips were, and do your best to lower the manifold straight down when reinstalling.
Allow to dry overnight.

- Eric

rjohnson442

In other words DON'T USE THE SEALS! if you want to be fancy you can use a punch to dimple the front and back so the sealer has something to bite into.

seansolds

If you are doing it yourself or have help, clean everything up set the manifold on the engine dry make sure you line it up exactly where you want it then use a marker, grease pencil or I use masking tape and mark the manifold front and back both sides so when you reinstall it drop it straight down on your marks then you won't have to move it.. I like to use permatex rtv black gasket maker in a pressurized can..cut a V notch in the dispenser. I cut a 1/4 inch width on bottom at least 1/2 inch tall to make a upside down V.. So when you place manifold on it squashes the V into a perfect square...like it was said before dimple the metal on the block every inch so the permatex has the dimple to grab on too..if you can remove oil fill tube for less obstacles and practice laying down a nice bead on a piece of cardboard first...torque per specs for the manifold run the car and retorque manifold after 3 cooling cycles after driving to make sure you have proper seal.. Work this method and you will be g2g..Good luck.. Sean

NDERISE

spray the surfaces where the r t v will go with brake clean so as to remove all oil from the surfaces to help the r t v to stick

Joeolds71

Those heavy iron intakes are a PITA. If your engine hoist is still available you can put a couple of bolts through a chain where the carb bolts on and use the hoist to lift it. Also works good for re-setting the intake. I knew a guy that actually made a plate that he could bolt to the carb area for this purpose. Of course you need to have the hood off to use the hoist, so it may not be practical.

BILL DEMMER

also, let the rtv set up for about 15 minutes before you drop the manifold on it. it'll seal better that way.


bill

MDchanic

In my experience, by the time you've applied RTV carefully to all of the right surfaces, avoiding smearing any excess anywhere it shouldn't be, at least 15 minutes will have passed anyway.

- Eric

NDERISE

I as an auto tech for 42+ years have done 100s of intakes on olds, Pontiac, buicks , chevys, cadillacs, fords and have always installed the intake wright after putting the r t v. and have had no problems with leaks. if there is a slotted hole in one of the intake bolt holes install a stud in it to help u guide the intake were it needs to be. letting it set causes it to skin over and it may not stick.
hope this help ray

BILL DEMMER

just going by my experience, i expect it to not seep/leak after many years. the way i do it-it doesn't.
rtv tends to shrink over time, keeping that in mind, by letting it form a light skin, the rtv remains under a little bit of tension as you assemble. this compensates for some of that shrinkage, and fresh(unskinned) rtv squeezes out, leaving no tension. all due respect to the previous posters, but my way works better and lasts longer.


bill

NDERISE

o. k. I,am finish with that

jpc647

What do you mean? People intentionally put dimples/grooves in the thin front and back mating surfaces of the intakes(where the rubber end seals would go)? Is this on the aftermarket intakes as well?

MDchanic

That's what I mean. On any kind of intake. I don't think it's strictly necessary, though.

- Eric

jpc647

Interesting. I was having problems with end seals on my new Edelbrock intake last summer, has to change them 3 times, no one ever suggested that. If it leaks again, I'll have to try that. Just small dimples like with a punch and small sledge hammer? In a line or randomly on the lip?

MDchanic

I've seen them both ways. Probably doesn't matter.

As I say, that RTV is a pretty good adhesive. If you've got the surfaces good and clean, it should stick whether it's dinged up or not.

- Eric

Allan R

The issue of dimpling/hatching was discussed on Steve's thread when he build his 455. (ah64pilot) I believe on his block he used a cross hatch pattern with a small straight chisel. If you want to PM him, he could address it first hand.