I have been loosing coolant from my 84 12a and I found where it is going. It is "pooling" on the top of the manifold. I can't detect any leaks from the water pump/hose connection on top. Is the motor done? Oil is clean but I am used to piston power and am rather new to the rotory.

Please Help!

 

Needs coolant o-rings in between manifold and engine. No big deal, just pull it off and replace them.

 

Thanks!

 

What stins is I just put everything on. New carb and such.....Oh well

 

At least it's always easier the second time around. You may also want to replace the intake manifold gasket along with the O rings when you do the job, it usually gets pretty warped.

 

Good Idea......May also be a good time to remove the rats nest.

 

plug them up. then its never an issue again

https://www.rx7club.com/1st-gen-archive-71/cooling-intake-how-install-freeze-plugs-532565/

 

That sounds like the way to go. Expecially since I am removing the nest!

Thanks

 

While I have everything torn down. Does anyone have any other suggestions of components I should change while accessible? Or better asked….What else breaks under all that. Motor has 140.000.

Thanks

 

Just the gasket and O rings, I'm pretty sure. If it were me, I'd be taking the time to do a thorough degreasing and cleaning and check on all the hoses and connections (at least those you have left after deleted the nest, but warning on removing the nest, you will probably loose a few mpg's on gas mileage).

About blocking off the coolant ports, I think the reason they are there is to warm the intake manifold so the carb will warm up faster. This seems like a good idea if want to shorten that stumble time in the morning, get a little better fuel economy and lessen emissions caused by having to drive with the choke longer than necessary.

Those O rings really are a low maintenance item, new ones (about $10 as I recall for the parts) should be good for the lifetime of the car.

Good luck with the project!

 

Ray, what happens when you block the coolant ports but don't block the ACV port? Heated exhaust air constantly pulses into the manifold. Even if you've blocked the ACV port on the outside of the manifold with a cover plate, there is still an open active ACV port on the engine right below the primary ports that no one seems to remember is there.

If you don't fill this port in with some sort of putty (I like quicksteel but a JB weld might work) what do you suppose will happen when you block the coolant ports only? Will the manifold run cooler or will it actually run hotter? Something I'd like everyone to think about so I don't have to repeat myself every time this subject comes up.