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-   -   Intake Manifold Coolant(?) Leak - Help Needed (https://www.rx7club.com/1st-generation-specific-1979-1985-18/intake-manifold-coolant-leak-help-needed-1128696/)

lordcupkake 07-31-18 08:20 PM

Intake Manifold Coolant(?) Leak - Help Needed
 
Okay, so this may be as obvious as I think it is or I may be missing something.

I took my 1983 Rx7 to a Mazda Dealership recently after I noticed a decent amount of thick white smoke upon startup (more than I thought could be contributed go an air/fuel mixture issue). I told the head mechanic, whom I spoke with directly, that I thought the issue was the engine was leaking coolant into the combustion chamber. He said based on my symptoms (which included a small amount of that burning smell from coolant) that he agreed with my preliminary diagnosis and would run some tests to be sure. I got called a couple times over the week they had the car and they told me that after running a couple tests (including a coolant system pressure test) that the issue was in fact that I had too large a carburetor (an aftermarket Holley which also happened to be somewhat malfunctional) on the vehicle and that it was, in fact, an issue of too much gas being entered into the chamber. I was glad to hear the news and conveniently I had an extra Nikki sitting around to replace the bum carb. Now, however, I went and removed the old Holley intake manifold and low and behold about 2-ish liters of what I am pretty sure is mostly coolant with a little gas mixed in (but I'm not entirely sure) came flowing right out.

Now I am sitting here and cursing myself for not trusting my gut and believing that the issue was a coolant seal leak and instead wasting extra time and money (which went toward ordering new interior pieces, etc.) on a car that is likely going to need an engine rebuild.

Am I missing something? Am I wrong in my diagnosis? Why would there be coolant(?) coming out of the intake ports if not? Can anybody straighten this out based on my description?
P.S. I believe the fluid to be coolant because it is greenish-yellow in color, does not smell like gas (except very slightly), and pretty much smells like coolant when compared to fresh coolant.

KansasCityREPU 07-31-18 08:26 PM

The two smaller ports on the intake are in fact for coolant.

Did you use the Racing Beat intake manifold with the Holley? The coolant ports are closed of with that manifold. On the factory manifold, the coolant is used to heat up the fuel.

Get a new intake gasket with two new coolant o-rings, use the factory intake manifold and Nikki carb.

racerx01 07-31-18 08:30 PM

Check the block offs for the intake manifold, maybe it is leaking from there. Or if not blocked off the little seals could be leaking. Pictures can help with the problem solving.

lordcupkake 08-01-18 06:35 PM

Thank you both! I found the source of the leak - it was leaking from one of the coolant ports on the engine, which were previously blocked. I have fixed the issue.

Jeff20B 08-01-18 11:23 PM

The coolant is used to keep the manifold from getting too hot due to exhaust gasses passing through it by way of the ACV.

No ACV? No need for coolant.

rxtasy3 08-02-18 06:34 AM

even with the coolant passage being blocked off, i would still use the O-rings.

Jeff20B 08-02-18 09:00 AM

Agreed about the o-rings still being a good idea.


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