Mike B

Malcolm, I say pull her! It's the only way to be sure

Seriously...It's a chance to do the 20 year check up and get to hoses you wouldn't even know were there. I know, I have issues

For RngTrtl "lol"

the flyin' scotsman

I'd like to Mike but just not now; there's maybe 4-6wks left before she gets put to bed for winter and I'd like to keep driving while realising that a bad WP just gets worse as time goes by.

Then seriously I may do the engine as the sump is leaking and the DS valve cover where I broke a bolt earlier this year. Never pulled a 928 before but have done many others. I'd also do the WP, rod bearings and all the 'other' stuff when the engines out. Perhaps its time.

SharkSkin

I feel your pain -- that last month of driving season is tempting. Lots of good advice above, especially the pressure tester. You can make one easily with a tee, a short length of hose, and a schrader valve, tied in to the small hose on top of the radiator. Pump it up with a bicycle pump to test. Or use some variation on that depending on what you have handy. You could block the existing hose, cut off the fitting from the end of the tire pump hose(repair later) and attach it to the radiator nipple.

To localize the noise a (relatively) simple check you can perform is to remove all of the accessory belts and run the engine to see if your noise is still there.

Also, FWIW, when my WP went out I was able to take off the DS TB cover and with a bright, focused light I was able to make out the trails from dripping coolant on the WP casting.

the flyin' scotsman

Update:..............the 'noise' comes and goes................when its there its at the front of the engine and I'm going with WP failing.................thx Roger for the confidence

The leak has stopped and I can only relate that perhaps the upper rad hose at the bridge needed the tweek.........either way I'm pulling the pump this winter for surety/ the engine may still come for all sorts.