Lex_GTX

Recently bought an 86 951 and I am dealing with all the issues the PO neglected.

The coolant level was a little low when I picked up the car so I topped it off with green off the shelf Prestone antifreeze in the overflow tank. Here's what it looks like once I did this.

I know these cars suffer from headgasket issues and oil cooler seals. I do see some small oil slick bubbles in there. For you guys with more experience what does this coolant tell you?

dillon410021

It kinda looks like dexcool antifreeze

Lex_GTX

What is recommended by Porsche in these cars? Green or the GM dexcool orange?

They should not be mixed or sludge will form.

dillon410021

Clarks garage says:


7.1 What anti-freeze should I use? The bottle says "safe for aluminum engines".
Although several list members use it, it is not recommended by Porsche. The bottles labeled "safe for aluminum engines" still contain phosphates. The only approved anti-freeze are ones that specifically state "Phosphate Free". There are several available products, including:

-Zerex Extreme 450 Phosphate Free
-Mercedes Benz anti-freeze, p/n Q.1.03.0002
-VW/Audi Autobahn anti-freeze, p/n ZVW.237.104

Lex_GTX

Thanks for the info. Does the coolant look like I have oil/coolant mixing? The small grease bubbles concern me but there is no obvious milkshake. The oil cap is also milkshake and coolant free.

The car is stock motor wise.

dillon410021

I would do a leak down test and compression test to see if the headgasket is leaking. I am not sure how to test the oil filter housing for leaks.

PorscheDoc

I would flush the entire system out a couple times with water, then refill with coolant/water mix and see what you have. Either way, that nasty coolant needs to come out of there. Drain the radiator, remove the coolant tank and flush that out best you can, fill back up with water, get to operating temp after bleeding the system (make sure the heater is on full hot to flush the heater core) to get everything circulating, then let cool, drain, and repeat. Do that a couple of times until everything starts to look clean, then fill up with a 50/50 mix.

supes6

also it should be around the minimum mark when the engine's cold... it will rise to the max mark when the engine warms up. if you put any more in, it just gets spit out the overflow hose when the engine is up to temp (at least on my car it does).

Darwantae951

Just want to clear something up that I heard, is there any truth to coagulation when you mix dexcool with the standard green stuff?

Lex_GTX

Yes there is. Orange and green stuff should not be mixed together. I will be flushing the system and filling with water before running the car.

I am still unclear on something. Are those small, round, oil slick bubbles in the coolant what you guys see when you have an oil housing seal leak?

Voith

use castrol nf, its nitrite, phosphate and amine free and so gentle to engine that I am tempted to drink it when having stomach trouble :>