Porsche Enthusiasts Club Forum

You're correct on the different t-stat ratings but I think a post 1999 928 is a rare beast <g>. The 1990 onwards t-stat opened 83C, earlier opened at 75C. Porsche will supply the later one which is fine (p/n of later one ends 17, earlier 16 so you can check when it comes.

Install it with relief valve pointing up (there's a cast arrow to show this on the housing).

When I poured in new coolant today was miffed to find I could only get in about 12-13L. Full capacity is 16L and I thought I'd completely drained the block (btw I found the block drains hadn't been tightened when coolant changed for previous owner - service records point finger at OPC...)

Asking on Rennlist seems even when people have engine out, all hoses off and water pump off they can never drain the block completely and the record first fill is about 13.5L. I'll check over next few days to see if level drops a bit so I can put in some more fresh coolant. It is dropping gradually.

At least I have a lot of spare coolant for top-ups as I bought 17L.

Hi Adrian

Last time I drained mine I got a fraction UNDER 14 ltrs in.....but I did drain it over night....which may have helped..... I then put in 8 ltrs of A/F and just under 6 ltrs of water.....

I ran it for a couple of days then added maybe 1/4 ltr of water tops....then after another couple of days I measured the specific gravity with my Snap-On A/F hydrometer and it read just under 60%, which was fine.

I seriously doubt anyone could get more than 14 ltrs in, unless the engine is stripped.

All the best Brett

Thanks for info Brett, and I declare you holder of world record for squeezing coolant into 928 at 14L!

What threw me was that with my previous 1988 S4 I couldn't ever drain one side of block, as access to plug is blocked by exhaust test pipe, so I never gave second thought to not being able to refill coolant to stated capacity.

The 91 doesn't have the test pipes, so access to the plugs is easy (but you still have to wear swimming trunks when you remove them).

Cheers,

Adrian