# o-ring leaking



## Mav (Mar 5, 2017)

Am sure o-ring between timing cover and intake manifold is leaking. Anybody know best way to replace? Can it be changed by pulling water pump or do you have to pull intake manifold? Have 69 400 RA3. 69 service manual is no help.....


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## PontiacJim (Dec 29, 2012)

Mav said:


> Am sure o-ring between timing cover and intake manifold is leaking. Anybody know best way to replace? Can it be changed by pulling water pump or do you have to pull intake manifold? Have 69 400 RA3. 69 service manual is no help.....


Pull the intake. If you pull the timing cover, you may simply repeat the leak. The intake bolts must be loose to correctly get the o-ring to seat. You want to tighten up on the long bolt on the timing cover so it draws the intake tight onto the rubber o-ring. If you tighten the intake first, the intake cannot move forward to be drawn tight up against the o-ring as you tighten the timing cover bolt to make a good seal. Once tight, then you tighten/torque down your intake manifold bolts. Lotta leaks because the correct tightening procedure is not done.


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## Mav (Mar 5, 2017)

Hey, thanks a lot Jim. I probably created leak myself, I pulled water pump and decided this time I would follow the torque specs....thought 30# was a lot on the 5/16 bolt to the manifold and sure nuf I broke it. Had a spare so just snugged it up, but then it started leaking big time at the manifold seal. What was surprising was how little info is contained in the 69 service manual, and my Motors manual is even worse, almost nothing on it. Have a new seal coming from Ames on Monday, so will proceed as you said. Again, thanks, really appreciate the reply. Mav


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## Goat Roper (Oct 28, 2014)

Do as PJ explained but start all the manifold bolts first then start tightening with the long horizontal bolt.
You want to pull it forward with the long bolt against the manifold bolts otherwise you may not be able to start some.
12 foot pounds on on the long bolt. 
You will also need the two manifold gaskets.
I used a very thin coat of Ultra Blue gasket sealant just on the two water ports on the front on the manifold gaskets.
Also check the inset where the O-ring goes on the manifold, mine had severe pitting and I filled the pits with JB weld and used the back side of a socket sprayed with dry lube to smooth it.


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## Mav (Mar 5, 2017)

Appreciate the help, yeah 12# on the bolt sounds more like it, maybe I misread the manual, but it sure looked like 30# on the long bolt...thought it strange the 2 bolts on each side (3/8) were 30# and the long bolt (5/16) was too. Ok, you guys have been great help, thanks, mav


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## Mav (Mar 5, 2017)

Just so I get this right did you put Ultra blue on both sides of gasket? Thanks mav


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## Goat Roper (Oct 28, 2014)

Mav said:


> Just so I get this right did you put Ultra blue on both sides of gasket? Thanks mav


Yes.


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## Mav (Mar 5, 2017)

I know what you are thinking, "is Mav ever going to run out of questions", but here goes, got intake off and cleaned up, looked for pits like you said you filled, and cant decide if its pits or just part of the casting. No bigger or deeper than a grain of salt, wondering how yours compared before I get out the JB weld? thanks, mav


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## PontiacJim (Dec 29, 2012)

Cripes amighty, is Mav ever going to run out of questions? Who knows at this point. But its why we are here. :thumbsup:

Yep, sounds like pitting to me. As small as the pits are, easier to take care of the minor blems not than later and it's one less problem area. 

I would tru to wire brush the surface first to get any of the corrosion out of the pits. Maybe a small battery post brush would do it or a fine wire brush. Then just put a light layer of J-B Weld on it and let it set up. Then with a good smooth tooth flat file, or something like 100-120 grit sandpaper wrapped around a course flat file, sand it down smooth giving you a nice even surface to seal up against. Won't take you any time at all. 

I had to do this on the inside of the timing chain cover that mates to the block and it had some deep pitting. Worked perfect and I did not have to purchase a new one


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## Goat Roper (Oct 28, 2014)

Better safe than to have to do it again, also check the male side and strike it flat with a file.
Tin Indian sells one that is a bit thicker and this is the one I used.

Pontiac Intake water crossover to Timing cover seal.

Tin Indian Performance Pontiac Intake Gaskets


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## Mav (Mar 5, 2017)

Sat and thought about it after I posted, and decided to go ahead w/the JB weld, seemed like cheap insurance and cant hurt. I smoothed it with the dry lubed socket (1/2 in. 13/16 fit it perfectly). Been on a couple hours, debating whether to smooth again or leave till tomorrow, yeah I cleaned up male side finished w/emery cloth, its very smooth. Found a real weak spot in the molded heater hose when I took it off so will be a few days before it gets here. Cant wait to get it back together, start it up and watch the water come out of the heater core! Thanks for puttin up w/me you guys, till next time, Mav


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## gtoearl (Dec 21, 2009)

*Goat Roper*



Mav said:


> Am sure o-ring between timing cover and intake manifold is leaking. Anybody know best way to replace? Can it be changed by pulling water pump or do you have to pull intake manifold? Have 69 400 RA3. 69 service manual is no help.....


 What gasket kit would you buy from tin Indian that would be for a standard 389 with number 16 heads. I Saw also they have block off plates. I think I will purchase those also. But I’m confused about what gasket kit to buy for a standard application and an RA application. I believe the ports are taller on those.


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## Goat Roper (Oct 28, 2014)

gtoearl said:


> What gasket kit would you buy from tin Indian that would be for a standard 389 with number 16 heads. I Saw also they have block off plates. I think I will purchase those also. But I’m confused about what gasket kit to buy for a standard application and an RA application. I believe the ports are taller on those.


I would call and ask.
Check your intake to see if the crossover is square or rectangular.
I made the mistake of looking at the heads instead of the intake and had to redo.
Used square when I needed rectangular.
The upside is now I can R&R the intake in about 30 minutes.
:grin2:


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## gtoearl (Dec 21, 2009)

I tried to call tin Indian. They only except emails. Can anyone including yourself recommend a gasket kit for my try power, 66. As I said I have 68 Heads #16 . I’ve been looking at the Fel-Pro line. 1233 seems to be for taller ports. The standard kit, which is what I think I need does not include block off plates. Getting very frustrated and confused. I just want to fix this thing so I can put it back on the road.


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## gtoearl (Dec 21, 2009)

Forgot to ask. Would heads do you have on yours.? What year manifold are you running and is it a try power?


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## BearGFR (Aug 25, 2008)

You might try giving Butler a call and talking with them. I've had reasonable luck talking to a live, knowledgeable person there - not GREAT luck, but reasonable luck.

Bear


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## gtoearl (Dec 21, 2009)

Thanks. What gasket set have you used on your intakes


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## PontiacJim (Dec 29, 2012)

If you have an exhaust leak between the intake manifold and head you will not fix it with a block-off plate. You simply have a problem with the mating surfaces or the old gasket just burned off, or the intake bolt loosened up allowing the gasket to leak. 

There is no trick to this. Simply go to the local auto parts store and get a set of intake gaskets for a 1968 Pontiac GTO (or any 400CI) and install them. You should not normally get the taller Ram Air gaskets, but even they will work. If you want to make sure, the standard intake opening will measure 2.05" tall and 1.13" wide. The RA IV gaskets will measure 2.18" tall and 1.16" wide.

While the intake is off, let a machine shop check the mating surfaces to make sure they are true and not warped or damaged. Inspect the intake surface on the heads to make sure there are no problems.

If all is good, make sure you tighten/torque up the long front bolt/rubber O-ring at the water pump/intake before you torque down the intake bolts to prevent any water leaks at the rubber O-ring. Some like to use a light coating of sealant on each side of the rubber O-ring to make sure it does not leak. Once you run the engine a little, go back and re-torque the intake bolts as they usually will loosen up a little.


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## PontiacJim (Dec 29, 2012)

Here is an article on fitting an intake/head combo when the exhaust ports do not match. It is a PDF file and should open if you click on it. Worked for me in opening it up.


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## gtoearl (Dec 21, 2009)

Thanks so much for your response Jim . Will follow all of your recommendations. One question though, what is your opinion of using block off plates. I didn’t think using them was going to fix my problem I just thought the car would run better with them and I wouldn’t get the constant burn off of paint across the exhaust crossover. One thought though, I suppose my manual choke probably won’t work very well.


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## Goat Roper (Oct 28, 2014)

gtoearl said:


> Thanks so much for your response Jim . Will follow all of your recommendations. One question though, what is your opinion of using block off plates. I didn’t think using them was going to fix my problem I just thought the car would run better with them and I wouldn’t get the constant burn off of paint across the exhaust crossover. One thought though, I suppose my manual choke probably won’t work very well.


Manual choke is activated by a pull out knob on the dash.
Divorced choke is a coil spring housed in the manifold connected to the carb by a rod.
Electric choke is mounted directly on the carb with wire attached.
If you have a divorced choke blocking the crossover will extend the time the choke is on.


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## PontiacJim (Dec 29, 2012)

gtoearl said:


> Thanks so much for your response Jim . Will follow all of your recommendations. One question though, what is your opinion of using block off plates. I didn’t think using them was going to fix my problem I just thought the car would run better with them and I wouldn’t get the constant burn off of paint across the exhaust crossover. One thought though, I suppose my manual choke probably won’t work very well.


I would not block off the exhaust crossover. Burned paint is kinda normal, although there is a thread on this if you do a search for it. Now if you were experiencing gas percolation, vapor lock, or a problem with the heat from the intake effecting the ethanol laced gasoline, I would suggest getting the phenolic spacers which will help: https://www.dashman.net/product.html?id=167 A 1/4" return line will also help if you don't already have one.


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## gtoearl (Dec 21, 2009)

Thanks.... not sure if I have an issue. What symptoms would I look for? Also not familiar with the 1/4” return line ad. Thanks


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## yeagergasfireplace (9 mo ago)

PontiacJim said:


> Pull the intake. If you pull the timing cover, you may simply repeat the leak. The intake bolts must be loose to correctly get the o-ring to seat. You want to tighten up on the long bolt on the timing cover so it draws the intake tight onto the rubber o-ring. If you tighten the intake first, the intake cannot move forward to be drawn tight up against the o-ring as you tighten the timing cover bolt to make a good seal. Once tight, then you tighten/torque down your intake manifold bolts. Lotta leaks because the correct tightening procedure is not done.


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## yeagergasfireplace (9 mo ago)

Looks like Ive got same problem


PontiacJim said:


> Pull the intake. If you pull the timing cover, you may simply repeat the leak. The intake bolts must be loose to correctly get the o-ring to seat. You want to tighten up on the long bolt on the timing cover so it draws the intake tight onto the rubber o-ring. If you tighten the intake first, the intake cannot move forward to be drawn tight up against the o-ring as you tighten the timing cover bolt to make a good seal. Once tight, then you tighten/torque down your intake manifold bolts. Lotta leaks because the correct tightening procedure is not done.


Hi, ive got same problem...I need the same water pump O ring gasket for my 1968 GTO (400 engine).
What part # is that? None of these auto parts places can find it.
Thanks!


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## Sick467 (Oct 29, 2019)

Ames has them...










Here's a link...



Search Parts



Here's what the pdf catalog says about the seal....

"This new design is slightly thicker than original or most aftermarket replacements
found in gasket sets putting an end to coolant leaks that are
common in this area."

Download your catalog here (just know that prices are going up and the catalog may not be up to date)...






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