Water pump

[Dave WM]

1st long distance drive (150 miles on Florida Turnpike) all good right up until I pull into my destination and then Steam...

open hood coolant everywhere, I feel the fan pulley noticeable play and noise when engine running. I thought it sounded a little off when I headed out a 0 dark thirty, but guess the lack of caffeine had me not thinking straight . 2 hour later 70-75 mph before the steam.Auto zone 9:00 am do not have it but can have it by 3pm (Sunday).  I did bring some tools but not my rad pressure tester. Auto zone comes thru and I get a rad tester (may keep it, nicer than my old one or AZ will refund me the entire purchase price). I was really fearing snapping bolts, but no prob, they all came out nicely. The AZ pump was the cast impeller type for 20$. Got some anti seize for the bolts (had to reuse) and some gasket adhesive (not sealant, but the stuff used to tack on the gasket). Maybe 2 hrs to pull and replace (gotta love how easy an L28 is to work on). pressure test, all good, back on the road and perfect temp never budged from just below the 1/2 way point, Oil pressure about 75 (if you believe the gauge) at about 3k rpm, a little higher at 3500 for 70 mph.

I really dodged the bullet not getting stuck out at yeehaw junction....

 

Edited October 10, 2016 by Dave WM

[Zed Head]

So what happened?  The seal and bearings went bad on the old pump and you had a slow fluid leak?  Out the weep hole?  How did the old pump look?  You didn't give it to AZ as a core did you?  Learning opportunity here...

And no over-temp on the gauge?

Edited October 10, 2016 by Zed Head

[Dave WM]

No warning signs of water leakage, if did get noisy maybe over weeks and I did not pickup on it. I would always check the engine bay after running and the rad after cooling, there was no loss of coolant, but most of my rides are short, just a few miles. The long trip high speed did it in. I did keep the core, will post up a video later to others can see/hear. I did not look it over to closely yet, but after getting it out it was clearly noisy and rough like shot bearings. My last Z (240 I had in the early 80's) threw a fan after breaking the pump shaft, taking out the rad on a lonely part of I-10 on a cold rainy night, not fun, this time I got lucky.

Edited October 10, 2016 by Dave WM

[hr369]

Have you checked your freeze plugs with an ice pick lately?  That's another thing to keep an eye on if they're original's.  Sounds like the seal blew fast and furious style. When was the last time you replaced

the radiator cap?  I had a head scratcher like this recently too with an Aisin water pump in my toyota. I would do a pressure test with the engine cold and it would test fine.

Then i would go for a longer drive and it would lose coolant and system pressure and start boiling. My warning sign was a little noise too.

Edited October 10, 2016 by hr369

[Dave WM]

no service history on the car, I have had it less than a year so no idea on how old the pump was. I should have replaced it before but I was so freaked out about horror stories on snapped bolts I had decided to leave it be if the was no weeping or excessive noise. I clearly must have missed something unless its possible to fail the quickly with no real warning signs. Of course like I said the noise "may" have been there before the trip started and I had just overlooked it. I am pretty sure there was no weeping bit its not impossible that it was slight and just went unnoticed.

[Zed Head]

I think that the bearings go bad because the seal leaks and lets water get to them.  So the rumbly bearings are a sign of a bad seal.  And the seal is going to leak more when the system is pressurized.  Might not leak much at zero pressure differential, so hard to see at the beginning.  The fluid that leaks is going to be warm and be blown back on to a hot engine.  So you could get steam without blowing the radiator seal.  I'd imagine that the only sign you might find is a very clean area around the weep hole.  Maybe fan shaped.

Just trying to figure out how you get an engine bay full of steam without running low on coolant.  If the gauge was still in the right range you probably did dodge the head warpage bullet.

[Dave WM]

ok lets say not full of steam I just saw some coming out from under the hood, and it was not until just after shutting down the engine. there was coolant everywhere, guess the pump leak hit the fan, I was slung everywhere forward of the engine. I am sure it did not overheat as I was watching it like a hawk the entire trip. I stopped for gas just a few miles short of the destination, no steam (so no leak yet?) and the temp gauge was rock solid after hitting the mid point.

after I shut down it did start to spike but even then it still did not go past about 3/4. I restarted the car and could not see any obvious leaking (was looking for a stream of coolant before I zeroed in on the pump). My guess is the heat spike may have built up enough pressure to cause the leak after the second stop (or maybe the 1s stop but went unnoticed.

it was more like wafting steam than live steam if that makes sense.

Oh and I have checked my temp gauge is pretty accurate (to the water temp in the rad).

 

Edited October 10, 2016 by Dave WM

[Dave WM]

here are some pics, video soon. the replacement pump from auto zone used the cast iron impeller and was 20$

 

[Dave WM]

video

 

[Captain Obvious]

Looks like the impeller vanes are worn shiny at the outside tips from contact with the front cover.

If that's the case, then no wonder it was noisy! You had metal to metal contact!

On edit - And if there was contact inside, what did the front cover look like?

Edited October 10, 2016 by Captain Obvious

[Dave WM]

gotta admit I did not pay attention to the front cover. I don't recall seeing anything shocking though that I would have made a mental note of.

Edited October 10, 2016 by Dave WM

[Dave WM]

any idea what that circlip looking thing in the last pic is all about?

Oh and yes the car sounds much happier now.

 

Edited October 10, 2016 by Dave WM