Hows it going everyone? I recently replaced my radiator for an aluminum one and was wondering if any regular coolant would work? Im also trying to run a mechanical temp gauge but I don't know how or where to install it. Im also wanting to reground the car but I don't where where the grounds are. Any help would be really appreciated.

 

Any regular coolant should work. Usually yellow in color.

Water or oil temp? Makes a difference.

Ground are on the driver side inner lower fender, just follow the negative battery lead to it. That also goes to the starter bolt as an engine ground. Theres a ground strap from the muffler to the hanger bracket thats usually missing. Theres a ground on the dash up underneath right behind the cluster. You have to be upside down right under the area to see it. Philips head screw with a black lead onto it. It doesn't hurt to add an extra ground to the front of the engine off that inner fender ground as well.

 

considering the question is concerning coolant, i think it's safe to say he's referring to coolant temp. i run a mechanical gauge and have it plumbed into the rear of the W/P housing.

as for grounds, i'm only aware of two places of ground wire off the battery. one is attached down low inside the drivers fender well and the other one attaches directly to one of the engine to trans bolts.

 

There is a factory water temp sensor on the back of the water pump housing. This is used to control the automatic choke. It keeps it pulled out until it reaches a certain temp.

I converted my water pump housing to an aluminum one form the second gen S4 (1986-1988). I also added an early water neck so I could add a sensor there. This gives a sensor before and after the t-stat.

 

>>>I converted my water pump housing to an aluminum one form the second gen S4 (1986-1988). <<<

how did you do this?

when I was swapping out a blown engine with a rebuilt one, things were going fast and furious, it was late at night, I was puttng the thermostat in, and I heard a little >>>PING !<<< The cast iron thermostat bolt hole cracked. So I had to wait 3 weeks for an e bay one the reach the end of bidding. And now I'm scared to replace the currently 16 year old thermostat because finding a OEM cast iron water pump housing will be astronomically harder now.

 

This thread explains what I did. https://www.rx7club.com/1st-generati...-12-a-1116674/

Parts:
1. S4 1986-1988 Water Pump Housing
2. S4 Water Pump and Gasket
3. S4 Water Pump Pulley
4. S4 Air pump bracket – if an air pump is installed
5. 12A Water Pump Neck