Cooling system issues

Naturally aspirated tech and talk
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jeyjey
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I've had decent luck bleeding my 944 a couple of times.

But I had to get a vacuum filler for the Flying Spur W12, so I'm looking forward to trying it out on the 944 next time around....

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'87 944 NA
'68 Series 2A, '96 E36 M3, '02 Vanquish, '15 Flying Spur

#11

libarra82
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I have the Astro Tools 78585 Vacuum Cooling System Kit, but I didn’t end up using it. After the engine rebuild, I was too impatient to hook everything up properly and just used the pump instead. I later discovered a radiator leak, so I stopped working on it for now. I’m hoping to have time this weekend to remove and inspect the radiator and decide whether to repair or replace it. The machine shop that reconditioned my cylinder head also specializes in radiator repair. The owner said they could fix it, so I may go that route if the cost is significantly lower than replacing it in the short term. Eventually, I plan to replace it, but my wallet needs a break for a little while.

#12

libarra82
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Update: I haven’t had a chance to work on the radiator yet, but I believe the system is now properly bleed. I let the car idle for about 30 minutes, it reached operating temperature. It ran well, no pressure buildup or leaks, and I’m getting heat from the vents when the heater is on. I also took it for a short 3‑mile drive with no issues.

Hopefully I’ll have time soon to work on the radiator.

#13

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Tom
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jeyjey wrote: Tue Apr 28, 2026 4:03 am I've had decent luck bleeding my 944 a couple of times.

But I had to get a vacuum filler for the Flying Spur W12, so I'm looking forward to trying it out on the 944 next time around....


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ooo... post your flying spur in the ok corral...! I secretly want one (or a Bentley Turbo R)... .

#14

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Tom
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libarra82 wrote: Tue May 12, 2026 7:39 pm Update: I haven’t had a chance to work on the radiator yet, but I believe the system is now properly bleed. I let the car idle for about 30 minutes, it reached operating temperature. It ran well, no pressure buildup or leaks, and I’m getting heat from the vents when the heater is on. I also took it for a short 3‑mile drive with no issues.

Hopefully I’ll have time soon to work on the radiator.
Sounds like progress! Beware if the radiator leak coolant out, air will get in to fill the void...

#15

libarra82
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Thanks, Tom. I took it easy on it. I’m sure if I pushed it, I’d get a different result. I might just go ahead and get a new radiator like you suggested and not worry about it anymore.

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libarra82 wrote: Tue May 12, 2026 8:47 pm Thanks, Tom. I took it easy on it. I’m sure if I pushed it, I’d get a different result. I might just go ahead and get a new radiator like you suggested and not worry about it anymore.
Spending other people's money is my super power. :lol:

But I do think that's the most reliable approach. :shifty:

#17

libarra82
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Your superpower is definitely strong, Tom :lol: Just got a new radiator along with the rest of the parts to finally wrap up the cooling system restoration.

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Taking out the radiator was actually pretty easy. I’ve been in that area so many times that getting to it felt second nature. All I had to do was loosen the bolts on the left and right at the top, no need to remove them completely. Then I tilted the radiator forward, lifted it up off the grommets, and slid it down and out from the bottom.

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The old radiator doesn’t look too bad. I might take it to the radiator shop, see if it can be repaired, and keep it around as a spare.

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#18

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