When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Working on pulling the FI wiring harness on the '84 928S that slept for 17 years. (details here)
To get better access to the wiring harness where it passes through the firewall, and to fix the leaking hose that connected the coolant overflow tank I removed the coolant overflow tank.
Here is what was inside - nasty gritty rust pellets and some big flakes. As one of our members pointed out in the main thread, that used to be my water pump.
The radiator had straight water in it, the block had antifreeze. What came out of the block when I changed the thermostat did not have rust in it and looked clean actually.
So to the "I am I insane" question - I was hoping to get this car running and actually use it. If I flush, repeatedly, the cooling system and replace the water pump and hoses is what I am seeing nasty but fixable?
Oh yes. Absolutely bonkers. But I'll tell you a secret.
All the best people are.
All that rust likely came from a couple different places. I would strongly suggest going through the whole cooling system (including the heater hose lines, valves and connectors). Flush it out good and put in good antifreeze.
It's not like dumping crap down the intake. I've seen some truly ugly stuff come out of cooling systems. A good flush, replace/repair the stuff that was rusting and the car was fine.
Oh yes. Absolutely bonkers. But I'll tell you a secret.
All the best people are.
All that rust likely came from a couple different places. I would strongly suggest going through the whole cooling system (including the heater hose lines, valves and connectors). Flush it out good and put in good antifreeze.
It's not like dumping crap down the intake. I've seen some truly ugly stuff come out of cooling systems. A good flush, replace/repair the stuff that was rusting and the car was fine.
Will keep going and flush everything and replace the lines etc.
Heater hose line looks like it is going to be difficult to get to...
Fixing one thing at a time works ok with a car that was maintained "recently", with a drove til it wouldn't run and sat for years I think you are much better off to do a full heads off refresh with all new hoses, cleaned injectors, new wires etc.
BTW getting both bolts that hold the overflow tank in is fun as I recall.
Tom, "insanity" increases exponentially with the number of cars you own. Not that it's a problem - I can quit any time, although there may be no improvement in sanity available to me regardless. Not willing to test that theory by the w, either way.
----
The rust flakes are from something that had a real steel surface to "share". A metal water pump impeller is typically a sintered rather than hot-cast piece, so its degradation product would likely be powder rather than flakes.
Try to get the block galley drains out. On a couple clinic cars, we ended up poking those drain ports clear with a bit of hard welding rod. The drains open into the bottoms of the cylinder jackets, an area that doesn't see a lot of coolant circulation. The flakes and other deposits settle in the bottom there and sort of solidify. Pull the thermostat and put the nozzle back on, then flush with the garden hose into the radiator ends of the big hoses to stir up and hopefully push out as much of that junk as you can.
Consider that the pH of the coolant got low enough to allow or cause the iron corrosion you are seeing the evidence of. The aluminum sacrifices too. Count your blessings if the heads are still in shape to hold a headgasket.
For those playing along at home, here's a reminder of why you MUST use the correct coolant, and change it every year or two. It's way too expensive if you don't.
Galley drains are steel bolts into the alusil block. Think about accelerated Galvanic corrosion with coolant circulating past the dissimilar metal junction. There are aluminum sealing washers on the bolts, so there's just no good way to get any PB Blaster or Kroil into the threads inside the washers. The bolts thread into some pretty stout bosses cast into the side of the block, but they are aluminum. I've never broken one, but there are reports here from folks that have. I use a 6-point socket in 1/2"-drive flavor, and a long handle and a sharp pull to break the bond. On assembly, use some TFE thread sealing paste on the threads, plus the washer, bolt and bloc sealing faces. Ignore the factory torque recommendation, instead using about 15 lbs/ft with the sealing paste. It will seal fine, plus it will come out again without damage in the future.
Fixing one thing at a time works ok with a car that was maintained "recently", with a drove til it wouldn't run and sat for years I think you are much better off to do a full heads off refresh with all new hoses, cleaned injectors, new wires etc.
Hi there. She has a new FI harness going in, new injectors and cap/wire/rotors already in. Hoping to get her running without having to pull the heads, we'll see.
Originally Posted by danglerb
BTW getting both bolts that hold the overflow tank in is fun as I recall.
Tom, "insanity" increases exponentially with the number of cars you own. Not that it's a problem - I can quit any time, although there may be no improvement in sanity available to me regardless. Not willing to test that theory by the w, either way.
Grin
Originally Posted by dr bob
The rust flakes are from something that had a real steel surface to "share". A metal water pump impeller is typically a sintered rather than hot-cast piece, so its degradation product would likely be powder rather than flakes.
Likely the metal tubes then, this part of the system had water rather than antifreeze.
Originally Posted by dr bob
Try to get the block galley drains out. On a couple clinic cars, we ended up poking those drain ports clear with a bit of hard welding rod. The drains open into the bottoms of the cylinder jackets, an area that doesn't see a lot of coolant circulation. The flakes and other deposits settle in the bottom there and sort of solidify. Pull the thermostat and put the nozzle back on, then flush with the garden hose into the radiator ends of the big hoses to stir up and hopefully push out as much of that junk as you can.
Will go after this next.
Originally Posted by dr bob
Consider that the pH of the coolant got low enough to allow or cause the iron corrosion you are seeing the evidence of. The aluminum sacrifices too. Count your blessings if the heads are still in shape to hold a headgasket.
Antifreeze that came out when I changed the thermostat looked good and clean actually, so I may have gotten luck on that. I'll know soon.
Originally Posted by dr bob
Ignore the factory torque recommendation, instead using about 15 lbs/ft with the sealing paste. It will seal fine, plus it will come out again without damage in the future.
The concentration of anti-freeze quickly levels out through the system. It doesn't separate into a water layer and an anti-freeze layer. What may happen is that the system leaks down, leaving a covered layer and an air-exposed layer. It takes a really long time for formerly coolant-immersed metal to start corroding, but stranger things have happened. The coolant deteriorates over time without changing appearance. Check the pH to be sure, looking for 8.8 to 9+ depending on the type of anti-freeze installed.
The concentration of anti-freeze quickly levels out through the system. It doesn't separate into a water layer and an anti-freeze layer. What may happen is that the system leaks down, leaving a covered layer and an air-exposed layer. It takes a really long time for formerly coolant-immersed metal to start corroding, but stranger things have happened. The coolant deteriorates over time without changing appearance. Check the pH to be sure, looking for 8.8 to 9+ depending on the type of anti-freeze installed.
08-21-2017, 05:48 PM
Am I insane?
