Hey everybody, here's my story/question right now. Well I did the whole emission system delete and when it came to blocking off the ACV plate I completely screwed up the bolt holes for the plate, and I think I have a coolant leak from the intake manifold, so When I saw a new manifold on ebay for 18 bucks, I figured I might as well buy it and block all the holes while it isn't on the car. I bought a new intake manifold gasket as well and the mazdatrix blockoff plate and acv gasket so I dont have to make my own. Now I hear there's a way to block off the coolant passages with freeze plugs, what exactly will i need to do that? And should I also remove the shutter valve and block off the shutter valve linkage holes while I'm at it? Any special tips for that?

 

Yep, I just did the freezeplug mod a few weeks ago. I got a couple of (I think) 14mm freezeplugs from autozone and put a little RTV on them and installed them. It was easy. As far as the other stuff, you should probably get someone else's opinion as my car hasn't worked right since the manifold and carb swap.

 

the engine coolant passages are 12mm. I recommend removing and blocking off the shutter valve with the manifold off the car, the screws typically need to be drilled out.

 

You want to put the freeze plugs into the engine, not the intake manifold. You CAN put them in the manifold if you want, but then you will still have coolant spilling everywhere every time you need to remove the manifold for servicing. If you put freeze plugs into the coolant passages on the engine, then you can take off the intake manifold without having coolant gushing all over the place. See this link for more info...

https://www.rx7club.com/showthread.p...ht=freeze+plug

I would also recommend removing the shutter valve when the manifold is off of the car. The butterfly in the manifold runner is very stubborn, and you will probably have to drill out the two screws that hold it in. After 25+ years those things are pretty much locked in place, and a screwdriver simply rounds them off. If you take the manifold off the engine then you can easily drill them out, and you don't have to worry about the shavings going into your engine. I use JB Weld putty to plug the hole that is left over from the shaft. Cut off a piece, knead it in your hands to activate it, and then smash it into the hole. Smoothe out the putty on both sides of the hole and you should be good to go!