Mopar 340 intake gasket replacement

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gavins1daddy

gavins1daddy

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Hi guys, I have a 340 that I’m replacing the intake gasket on. I’m wondering if I should use the front and back corked gaskets that come with or just use RTV. Also as this is my first time doing this I was wondering if someone has a link to a video I can watch on how to do this. I’m a very visual person, I learn better from watching than reading.

Thanks
 
I wonder if most people know why the ends of the intake manifold are called China Walls? Yes I know the answer.
 
I just replaced the intake gaskets on my 318 a couple of weeks ago. I didn’t use the cork gaskets but Permatex Ultra Black instead on the China walls. Depending on the intake manifold you’ll be putting on, you might need to cut off the dowels (one on front wall and one on back wall) so the intake manifold sits properly. Also used a small amount of Ultra Black around the 4 coolant ports between the gasket and intake. On the rest of the intake gasket (both sides) I used gasgacinch.

The 4 intake manifold bolts around the base of the carb will be difficult to take out and retorque properly if you don’t have a 3/8” drive 9/16” torque adaptor. If you don’t plan on removing your distributor, that torque adaptor will also come in handy on the two intake manifold bolts that also support the throttle bracket.
 
Pretty straight forward. I have done it twice in the last 3 months. First time with rtv, second with cork on the walls. I like the cork better... cleaner and easier to make sure that it is sealed. Had a small leak with RTV. With the cork I was able seal it up better. This is a great couple pics from @krazykuda right here. Intake/Head Gasket Question
 
Ok. I read that you put some etc around coolant ports. How much? Stumblinhorse, did you do this. Also if you use the cork gaskets on the front and back do you still apply rtv in the corners?
 
I usually put a small bead around the coolant ports on the gasket on both sides and yes you need to put RTV in the corners when using the cork gaskets.
 
gavins1daddy said:
Ok. I read that you put some etc around coolant ports. How much? Stumblinhorse, did you do this. Also if you use the cork gaskets on the front and back do you still apply rtv in the corners?
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I just used rtv in the corners, no where else and not much. I used hi-tack on both sides of the intake gasket and cork. Stuck all gaskets in place and then put the manifold down and finger tighten the bolts overnight, torque to 35 the next morning.
 
Weather using gasket sealant or gasket maker the directions need to be followed, some need to set for a certain amount of time before torquing. Others just need to be tacky before assembly, most gasket maker is supposed to be cured before returning to service
 
Probably not the proper way of doing things, but when I changed mine I used the cork gaskets and some rtv, and used a wrench to snug the intake bolts nice and tight, after a test drive or two I made sure they hadn't loosened up any, and here we are 6 months later with no leaks.
 
I used Mopar black RTV on my 273 but I milled the heads and the intake to match. There wasn't much gap between the intake and china wall for a gasket. I cleaned everything, applied a bead, waited for it to set up a bit (10-15 min.), installed the intake and torqued to spec. After curing overnight, I came back and trimmed with a razor blade. The engine wasn't in the car so letting it cure before running wasn't a issue. If it was in the car I would be comfortable with letting it set overnight before running the engine.
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When I replace an intake manifold I use right stuff or RTV instead of cork gasket on aluminum intakes. For cast iron usually use the cork. Just my two cents. Dustin
 
It's called the China wall because it's curved like the great wall of China. True fact!
 
Dartsun said:
When I replace an intake manifold I use right stuff or RTV instead of cork gasket on aluminum intakes. For cast iron usually use the cork. Just my two cents. Dustin
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And don't forget to pull the alignment pins if you are installing a aluminum intake.
 
There is a video of IMM Engines (Brians dad in the video) installing intake gaskets and installing the intake. I can't seem to find it. It was in a HotRod or Carcraft article.
Show in detail how it needs to be done with aluminum intake.
 
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Funny how I've been working on this stuff for 59 years and that China Wall deal just came out of no where... never heard of it until a few years ago. We used to call that area the engine block... those cork gaskets the "manifold end gaskets"...
 
Here's the guys (David Freiburger and Steve Dulcich) from Roadkill garage installing an intake. An if you haven't seen it, they have a whole series on how to build your 1st engine.

 
None2Slow said:
Here's the guys (David Freiburger and Steve Dulcich) from Roadkill garage installing an intake. An if you haven't seen it, they have a whole series on how to build your 1st engine.

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I would like to meet those guys someday just for fun. Dulcich is a Mopar guy at heart.
 
Did you ever see the "tour" of his engine room? Have to be a Motor Trend on demand subscriber and its on the Roadkill Extra. First 30 days free.
 
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