I just read all the threads on the using the correct coolant and since I am not sure what the PO had used. I am also in the process of replacing the radiator that I purchased from 928 International. Currently the block is full of the old green coolant
Also I replaced the thermostat with a new rubber gasket.
I am not happy with the bottom bolt to the neck in front of the thermostat. It appears to be a longer bolt on the bottom than the top. It feel that if I turn to hard it will strip. When I removed it the bottom bolt was not all that tight compared to the top shorter bolt.

I want to flush the system so the question is...do I finish the radiator install, fill with distilled water, run the engine, heater on then drain. and replace the distilled water with proper coolant. Thinking of using either Porsche coolant per Greg Brown
or VW/Audi.
Will one flush be Ok or should I do it more than once?

Van

 

head to the store and grab a few gallons of distilled water. flush it a few times to be sure. once it drains clear, drain a measured amount and replace with the proper amount of coolant to get the right mix.

Did you try swapping the bolts? One hole might be shorter than the other, I can't recall....

 

Thanks
Yes I did swap the bolts and the longer one goes on the bottom. Only Porsche can come up with engineering like this. My Alpine, one bolt fits all
When tightening, I can get that awful feeling that the bolt is going to strip out as I tighten it. It's snug now. If it leaks I may have to put a helicoil or something to correct it. At least I can get to it

I will follow your advice on the flush
Thanks
van

 

Van--

If you are at all concerned avout the flush (and I would be...) to get ALL the old coolant out, I'd think about pouring a few ounces of Tide liquid laundry detergent in there with hose water, and running the engine a bit. The detergent will grab any stray old coolant along with any stray petro fluids that might be iin there. Then flush with hose water again thoroughtly, with block drains out. Close everything up, and put in the coolant, Water Wetter, then distilled water.

On the thermostat bolt, I have the same symptom of it just not feeling tight in the threads. But mine is holding fine. Next time it's apart, I may put a stud in there with a little LokTite, and secure the housing with a Nylok nut. On my S4, unless you break the fuel line that runs across there, getting the factory bolt lined up perfectly can be a chore. So it's easy to get the bolt started a bit crooked if you shortcut the fuel line removal. Aluminum could be damaged a bit and it's downhill from there.

 

Thanks Dr Bob
Where are the block drains?
Why Tide? Just curious and I will use it.

v

 

Check out Dwayne's garage coolant drain. In addition to what Dr. Bob said, this has some pictures of where the drain plugs are, plus lots of other good tips.
It is an S4 patient, but the relevant stuff is the same: http://www.dwaynesgarage.norcal928.o...0Procedure.htm

 

Thanks Michael
Just how cool is Dwayne for doing this?
Hope all is well with you

Not sure if I will make it to LA on the 19th, my younger daughter is about to have a baby, due on the 20th.

 

Dwayne is cooler than a freshly flushed 928 .

I am well. Thank you

Here's to a healthy birth and hoping to see you soon,

Michael

 

Block drains are on either side of the block, a couple inches above the girdle. 13mm Heads on the bolts, needs a 6pt socket and a 1/2" breaker bar to get them loose. Put some teflon thread sealing paste on the threads and the aluminum washers when you reassemble. You can go with maybe 15 lbs/ft on them and get a great seal, and give yourself a chance to get them out again in the future.

The Tide is a pretty good grease remover and flushes/rinses pretty completely in cold water. Same features you look for in your laundry detergent. Others probably work as well. Get one with the color-safe bleach alternative if you have a bright-colored car... Tide is a common recommendation for removing oil from coolant if you have an oil or trans cooler leak into the cooling system.

 

I have been thinking of the advice to add tide to the coolant system,
Frankly I dont think its a good idea, here is why,

The cleaning material may damage and or remove parts of the head gasket that coolant wont touch ,
this can lead to a weakened HG seal somewhere in the coolant system,
Thus creating a failed HG,

NOTE the results of cleaning the system may not be seen for a while however.

The only time I would suggest to add any type of cleaner,
is to remove oil from the system,
IE from a failed cooler,
other than that simply draining the block and flushing with water,
then draining again will be sufficient.
Use distilled water found at the supermarket.

When doing a coolant change its a good idea to swap out
the thermostat
the rear seal,
the front O ring ,
the coolant bottle cap,
the heater control valve,
the short hose.
NOTE use new bolts for the thermostat housing you can get these at ACE hardware. use some antiseize on the bolts and Dow Corning 111 on the front O ring
I like the Zerex G 05 coolant.

NOTE the 928 uses about 4 gallons of coolant to fill the system so 2 gal of water and 2 gal of coolant are needed.

Note its a self bleeding system so just fill the bottle with the car sitting flat , run the engine with cap off,
open the heater control
and run the engine till the fans come on.
Install the cap then drive for 5 miles with the heater on,
park the car, let it cool off then top up as necessary

 

Stan, I respectfully disagree. The 'old' coolant is glycol-based, and can use the help of a pH-neutral emulsifier. The detergent does nothing to the headgasket material, everything to getting as much of the old coolant out as possible. I worry a lot more about supposedly-AL-friendly flush chems that are part TSP, where there's a risk of hideout around the o-ring seals on the end tanks for instance, or where gaskets may have already deteriorated some. Or at the seal on the thermostat housing the water bridge, etc. Since the emulsifiers in the Tide are much more soluble in water, they are much more likely to exit with the rinse water.

I spent more than a few years working for P&G early in my first career. I've watched more liquid Tide in five minutes than a flock of washer-women will use in a lifetime. Trust Me...

 

I would not use any tap water, only distilled. Tap water is going to damage your old, aged head gaskets and your water pump impeller assembly. Tap water will cause corrosion, so don't use it. Fill it up with distilled water and then drain until yo get rid of the old coolant. I would undo the two block drain plugs on every flush. You don't need to use laundry stuff to clean the inside of your cooling system. They sell stuff just for that.

 

I'm just rebuilding my water bridge and I cannot get the rear thermostat seal to fit in. It's as hard as a rock with no give to it.

Tried, hot water and soap but no joy.

I'm using part # 928 106 163 00.

Anyone had this problem, suggestions are welcome.

Alex

 

Are you sure the old seal is out? Sometimes it looks there is no seal as the old one gets all crudded over. You have to collapse it to the middle to get it out.
Year and model?

 

Hi Bilal,

You are correct the ring is still in there (Dah!!), thought it was part of the casting since I removed most of the crude.

I don't want to crack the bridge so will proceed carefully, any suggestions?

The bridge went out to powder coating which includes some oven time so I'm worried that the ring is really 'cooked' in there.

Alex
87 S4, Black on Black, 5 sp