Hey guys, after finally sorting out my driveline vibrations I now have a new issue. I noticed that I have some coolant dripping down the rear of the engine. Appears to be dripping off the intake manifold. It also appears to be pooling on top of the manifold as well. Others have said that It is caused by worn out manifold o-rings, Is that true? I already have a new gasket/o-ring set, but just wanted to confirm that it is coming from those o-rings. Also, are the 20mm freeze plugs worth putting in?

 

Yes - this is true. You hope it's the intake water gaskets and not the housing seals. 99% it's the intake.

When taking off the intake/carb, do it as one assembly. Remove the 6 bolts/nuts from the intake, disconnect the three cables from the carb, fuel lines, electrical connections, and the bolts (3) that bolts hold the vacuum rats nest in place, No need to disconnect all the vacuum hoses.

 

Good advice for the carb removal! Also a good time to inspect the feed and return hoses and replace if necessary.

I use a bit of Hylomar in either side of gaskets like this one.

I would recommend draining your coolant somewhat, from drain plug on drivers side of center iron at the bottom. If you don't do this, it will drain out all over the place once the manifold comes off anyway. Ensure to refill and bleed the system properly after.

Freeze plugs I would say are not worth putting in, not on a stock car at least. The coolant loop and your Nikki will give you proper warmup and drivability.

Also inspect your housings where the o-rings seat. Could be pitted and corroded, new o-rings could go in with a bit of coolant specific RTV to help seal.

 

awesome. I've decided that I'll combine this replacement with a full coolant refresh. Is there any special way to bleed the air? I'm relatively new to rotaries. So anything helps. I'm also picking up one of those prestone coolant flush kits as well.

 

You could try a Vacuum Purge Tool, Cooling System Vacuum Purge & Coolant Refill Kit

Your local Canadian Tire or Princess Auto may have something similar.

 

I found I was able to get all the air out of the system just by having the front end of the car raised and very frequently squeezing both upper and lower rad hoses as you add coolant.

Fill rad almost all the way, squeeze a hose, add more coolant, repeat.

 

It helps to have to front end lifted so the radiator fill is the highest point of the cooling system, and running the engine with the heater on will make sure all the air is out of the heater circuit as well.