Intake manifold is it stock..which gaskets to use

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Originalowner73 340duster

Originalowner73 340duster

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Ok maybe dumb questions..i got my car almost ready to go on the road an noticed the intake manifold is leaking very lightly out the front also getting few bubbles from thermostat surface of intake
1522444147929816498273.jpg
..must need to be resurface flat.have new thermostat housing..want to know if I have a stock one or aftermarket and how to tell..and which gaskets are the best to use also any tech tips for the installation would be appreciated..sorry if seems simple stupid..but im new to the cars and would just like information instead of doing it trial and error
 
Originalowner73 340duster said:
Ok maybe dumb questions..i got my car almost ready to go on the road an noticed the intake manifold is leaking very lightly out the front also getting few bubbles from thermostat surface of intakeView attachment 1715159171 ..must need to be resurface flat.have new thermostat housing..want to know if I have a stock one or aftermarket and how to tell..and which gaskets are the best to use also any tech tips for the installation would be appreciated..sorry if seems simple stupid..but im new to the cars and would just like information instead of doing it trial and error
Click to expand...
Looks like a factory iron intake
 
Originalowner73 340duster said:
I know it wouldn't be much..but nice to play a little if I got time.. recommend any specific gasket..and any technical tricks besides sealeant in the corners and front and back??
Click to expand...
Yeah. Go get a random junk iron intake and practice on. It's very easy to screw up a runner/port. Port it wrong and you can actually kill power. Make the port too big and it won't seal. Practice is key.
 
Use the Felpro print O seal gaskets (blue with the waxy looking coating) with a thin film of RTV on both sides around all the coolant ports.
RTV or Right Stuff the corners and both ends instead of the cork, and also use sealer on the intake bolt threads.
Most feel that sealing the threads is good enough, but I like to use sealer between the bolt shaft and heads as well, as it keeps oil from weeping between the gaskets and intake allowing oil to come up around the bolts even though the threads are sealed.

It also helps to set the intake on dry first, and find out what the front and rear gap is going to be so you don't undershoot the height of the sealant and have a leak.

Also note that left front corner (passenger side) of the intake where it mates with the China wall, as they come together a little strangely in that corner.

I try to do the sealer and get the intake on as quickly as possible after the China wall beads so the sealer actually sticks to the intake when it sets down.
The chances of it leaking is much higher if you let the sealer skin over before the intake goes on.

I have only done about 50 of them, so take my opinion with a grain of salt.:D

Also my opinion is to practice porting on something that doesn't have to be used as dukeboy mentioned.
It's just WAY too easy to trash a head when beginning.

BTW, I only EVER use red RTV on thermostat housings with no gasket and never have leaks there either.
Put it together with the sealer wet, and wipe off any that seeps out the edges, and it should be ready to go as soon as it's assembled and filled.

Also, on the thermostat, do yourself a favor while it's out and drill a 1/8 hole in the plate of the stat and you will never have air bubbles in the engine when refilling with coolant.
The hole lets the air circulate out before the engine ever warms up, removing the possible burping out of the coolant before the stat opens.



Here's an example when done and running.

MagnumswapLA.jpg


Thermostat.jpg
 
I'm not claiming I've done 50 manifolds and never ever had a leak, but I pretty much don't do anything previous poster does other than drilling the hole in the thermostat.
I don't understand what the "left front corner (passenger side)" even means.
And I don't understand the fascination with those Chinese chrome thermostat housings. It seems I'm always reading about them not sealing properly. Myself, I just get a cast iron one from NAPA, and paint it to match the engine. They are more rigid, flatter, and don't distort like the aluminum ones. I'll live with the extra 5 ounces of weight.
 
TrailBeast said:
Use the Felpro print O seal gaskets (blue with the waxy looking coating) with a thin film of RTV on both sides around all the coolant ports.
RTV or Right Stuff the corners and both ends instead of the cork, and also use sealer on the intake bolt threads.
Most feel that sealing the threads is good enough, but I like to use sealer between the bolt shaft and heads as well, as it keeps oil from weeping between the gaskets and intake allowing oil to come up around the bolts even though the threads are sealed.

It also helps to set the intake on dry first, and find out what the front and rear gap is going to be so you don't undershoot the height of the sealant and have a leak.

Also note that left front corner (passenger side) of the intake where it mates with the China wall, as they come together a little strangely in that corner.

I try to do the sealer and get the intake on as quickly as possible after the China wall beads so the sealer actually sticks to the intake when it sets down.
The chances of it leaking is much higher if you let the sealer skin over before the intake goes on.

I have only done about 50 of them, so take my opinion with a grain of salt.:D

Also my opinion is to practice porting on something that doesn't have to be used as dukeboy mentioned.
It's just WAY too easy to trash a head when beginning.

BTW, I only EVER use red RTV on thermostat housings with no gasket and never have leaks there either.
Put it together with the sealer wet, and wipe off any that seeps out the edges, and it should be ready to go as soon as it's assembled and filled.

Also, on the thermostat, do yourself a favor while it's out and drill a 1/8 hole in the plate of the stat and you will never have air bubbles in the engine when refilling with coolant.
The hole lets the air circulate out before the engine ever warms up, removing the possible burping out of the coolant before the stat opens.



Here's an example when done and running.

View attachment 1715159237

View attachment 1715159238
Click to expand...
That's nice looking girl for sure!!
 
rustycowll69 said:
I'm not claiming I've done 50 manifolds and never ever had a leak, but I pretty much don't do anything previous poster does other than drilling the hole in the thermostat.
I don't understand what the "left front corner (passenger side)" even means.
And I don't understand the fascination with those Chinese chrome thermostat housings. It seems I'm always reading about them not sealing properly. Myself, I just get a cast iron one from NAPA, and paint it to match the engine. They are more rigid, flatter, and don't distort like the aluminum ones. I'll live with the extra 5 ounces of weight.
Click to expand...
I needed one and that's what they had in stock or would have went cast..oh well was only 11 bucks..
 
TrailBeast said:
Use the Felpro print O seal gaskets (blue with the waxy looking coating) with a thin film of RTV on both sides around all the coolant ports.
RTV or Right Stuff the corners and both ends instead of the cork, and also use sealer on the intake bolt threads.
Most feel that sealing the threads is good enough, but I like to use sealer between the bolt shaft and heads as well, as it keeps oil from weeping between the gaskets and intake allowing oil to come up around the bolts even though the threads are sealed.

It also helps to set the intake on dry first, and find out what the front and rear gap is going to be so you don't undershoot the height of the sealant and have a leak.

Also note that left front corner (passenger side) of the intake where it mates with the China wall, as they come together a little strangely in that corner.

I try to do the sealer and get the intake on as quickly as possible after the China wall beads so the sealer actually sticks to the intake when it sets down.
The chances of it leaking is much higher if you let the sealer skin over before the intake goes on.

I have only done about 50 of them, so take my opinion with a grain of salt.:D

Also my opinion is to practice porting on something that doesn't have to be used as dukeboy mentioned.
It's just WAY too easy to trash a head when beginning.

BTW, I only EVER use red RTV on thermostat housings with no gasket and never have leaks there either.
Put it together with the sealer wet, and wipe off any that seeps out the edges, and it should be ready to go as soon as it's assembled and filled.

Also, on the thermostat, do yourself a favor while it's out and drill a 1/8 hole in the plate of the stat and you will never have air bubbles in the engine when refilling with coolant.
The hole lets the air circulate out before the engine ever warms up, removing the possible burping out of the coolant before the stat opens.



Here's an example when done and running.

View attachment 1715159237

View attachment 1715159238
Click to expand...
And which size stat you running..I think mine is a 195 is a 185 better??
 
Originalowner73 340duster said:
And which size stat you running..I think mine is a 195 is a 185 better??
Click to expand...

I run a 195 because I have a newer Magnum motor made to run in that range.
The pic I posted is a Magnum motor dressed as an LA.
Could be off base on it, but I feel 195 is a bit on the hot side for the older motors with larger bearing clearances, and some feel that the hotter they run the cleaner they run.

Obviously just one person's opinion.:D
 
Ok in my Chilton's manual it sayd the torque of the intake manifold is 37- 47 ft lbs...is that correct seems little high to me but what do I know..wanted to chk with you guys before I get up to it..
 
Originalowner73 340duster said:
Ok in my Chilton's manual it sayd the torque of the intake manifold is 37- 47 ft lbs...is that correct seems little high to me but what do I know..wanted to chk with you guys before I get up to it..
Click to expand...

That's about right, but it's almost more important that they be fairly evenly torqued than how much.
Use the recommended sequence and do about 40, but you will also notice intake bolts can't all be torqued anyway. (things in the way of getting on the bolts)
Personally, I just use a box end wrench and use the tightening sequence and get them all good and snug in three tightening steps.

Once they are down snug you can use your torque wrench on some you can get to, and then feel what it takes to tighten it just a hair more with a box end wrench.
Then you can estimate that same feel on all of them with the wrench.
 
TrailBeast said:
That's about right, but it's almost more important that they be fairly evenly torqued than how much.
Use the recommended sequence and do about 40, but you will also notice intake bolts can't all be torqued anyway. (things in the way of getting on the bolts)
Personally, I just use a box end wrench and use the tightening sequence and get them all good and snug in three tightening steps.

Once they are down snug you can use your torque wrench on some you can get to, and then feel what it takes to tighten it just a hair more with a box end wrench.
Then you can estimate that same feel on all of them with the wrench.
Click to expand...
I always do the 3step torque method..and thanks man!!
 
TrailBeast said:
Use the Felpro print O seal gaskets (blue with the waxy looking coating) with a thin film of RTV on both sides around all the coolant ports.
RTV or Right Stuff the corners and both ends instead of the cork, and also use sealer on the intake bolt threads.
Most feel that sealing the threads is good enough, but I like to use sealer between the bolt shaft and heads as well, as it keeps oil from weeping between the gaskets and intake allowing oil to come up around the bolts even though the threads are sealed.

It also helps to set the intake on dry first, and find out what the front and rear gap is going to be so you don't undershoot the height of the sealant and have a leak.

Also note that left front corner (passenger side) of the intake where it mates with the China wall, as they come together a little strangely in that corner.

I try to do the sealer and get the intake on as quickly as possible after the China wall beads so the sealer actually sticks to the intake when it sets down.
The chances of it leaking is much higher if you let the sealer skin over before the intake goes on.

I have only done about 50 of them, so take my opinion with a grain of salt.:D

Also my opinion is to practice porting on something that doesn't have to be used as dukeboy mentioned.
It's just WAY too easy to trash a head when beginning.

BTW, I only EVER use red RTV on thermostat housings with no gasket and never have leaks there either.
Put it together with the sealer wet, and wipe off any that seeps out the edges, and it should be ready to go as soon as it's assembled and filled.

Also, on the thermostat, do yourself a favor while it's out and drill a 1/8 hole in the plate of the stat and you will never have air bubbles in the engine when refilling with coolant.
The hole lets the air circulate out before the engine ever warms up, removing the possible burping out of the coolant before the stat opens.



Here's an example when done and running.

View attachment 1715159237

View attachment 1715159238
Click to expand...
My felpro pro gaskets came with red plugs they said to put in second whole on every side. What it that for??
 
rustycowll69 said:
you may notice that those particular bolt holes are counterbored or spot-faced to make a slight recess to allow for those plugs to hold the gaskets in place for assembly purposes.
Click to expand...
Ok but if I install them and it obviously doesn't look right don't use them? And if I do use them should I rtv/ right stuff them in?
 
Ok wanna do this intake manifold tomorrow.but I'm thinking now..is it worth it to get a aftermarket one now since I'm taking it off?? If yes I could use some recommendations..not sure what is done to motor ..has headers and definitely a cam..
 
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