P38A 4.6 Thor Water pump wobbler

I’m in the process of recommissioning a very unloved P38, and I’ve just had a near miss (heart in mouth moment!)

I’ve removed the radiator, viscous fan and coolant hoses for replacing, and I’m waiting for parts. I did run the engine up to operating temperature without coolant, which I realise isn’t advisable, but I did it anyway!

I had to move the car tonight just a few meters, but I couldn’t push it. When I started the engine, the water pump pulley almost threw itself off the engine, which was not a nice sight!! I immediately stopped the engine and thought better of it! I’ve taken the belt off, and while there is a bit of play in the bearing, it’s minimal, and it spins concentric although there is a bit of a grumble.

My guess is that I’ve probably overheated the bearing and it’s goosed?

Well... you sound like me.
A P38 menace

If it’s wobbling/grinding water pump is shot. Mine did that then blew out the rad on its evacuation.

V8 has issues if overheats running temp is okay.
No coolant may cause hotspots/warping, you may be lucky

RangeRoller dt said:

Well... you sound like me.
A P38 menace

If it’s wobbling/grinding water pump is shot. Mine did that then blew out the rad on its evacuation.

V8 has issues if overheats running temp is okay.
No coolant may cause hotspots/warping, you may be lucky

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Haha yeah I can’t leave it alone I wondered what the hell I’d done when I first bought it, but everytime I sit in it and especially when I start the engine, my love for it grows

Yeah that’s what I thought! It was scary and funny in equal measures! I may as well add a new water pump to the list. My postie is beginning to loathe me with all my parcels

Why on earth did you drive it without coolant lol!

Don’t give me the 2ft nonsense, running temp

It’s green oval syndrome. It makes your thinks funny

Just gives me an excuse to spend even more money on the bloody thing

Wtf have I done! I’m mega worried about it now I just went off the premise that if the gauge didn’t go above half, then it would be fine. I feel like crying!!

If there's no coolant then there's nothing for the sensor to measure, it will get very hot very quickly with no coolant. A few seconds would be ok but i wouldn't want to run it for say, a whole minute!
Your water pump will likely burn out seals in next to no time with no coolant as well, so it's something you'd do with the belt removed

kermit_rr said:

If there's no coolant then there's nothing for the sensor to measure, it will get very hot very quickly with no coolant. A few seconds would be ok but i wouldn't want to run it for say, a whole minute!
Your water pump will likely burn out seals in next to no time with no coolant as well, so it's something you'd do with the belt removed

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That’s what I fear there was whatever coolant is left in the engine block still in there if that makes any difference?

If the block was full to the pump then that's got to help! Something to soak up the heat.
As had been said, maybe you've been lucky! Full it back up and see how you get on

kermit_rr said:

If the block was full to the pump then that's got to help! Something to soak up the heat.
As had been said, maybe you've been lucky! Full it back up and see how you get on

Click to expand...

It was an attempt to flush out the coolant, so was waiting for the thermostat to open and flush the old stuff out. One of those decisions that might come back to haunt me
Watch this space, there could be a late model P38 breaking for spares coming soon

Thermostat probably won't open without coolant in the system. It will sit in cooler water remaining at the bottom !!. Sensors at the top of the engine will take time to register real block temp, by which time you have overheated.

Best to rebuild the cooling system, then refill properly ( . . . "according to RAVE" . . . ) and then check for leaks using static pressure. Finally get it up to temperature and do the extra bleed, etc.

Before all this replace the wobble water pump just because . . . . . .. . .

pwood999 said:

Thermostat probably won't open without coolant in the system. It will sit in cooler water remaining at the bottom !!. Sensors at the top of the engine will take time to register real block temp, by which time you have overheated.

Best to rebuild the cooling system, then refill properly ( . . . "according to RAVE" . . . ) and then check for leaks using static pressure. Finally get it up to temperature and do the extra bleed, etc.

Before all this replace the wobble water pump just because . . . . . .. . .

Click to expand...

Thanks for all the advice. It’s nice to hear, when really I should be reprimanded other than the water pump, the engine sounded spot on. I’ve got new hoses on the way and a water pump now ordered, so fingers crossed!

Btw, do you normally get a gasket with the pump? Most of the eBay offerings do, but a few don’t mention it

Hope you ordered one with a metal impeller, heard bad things about the plastic ones

kermit_rr said:

Hope you ordered one with a metal impeller, heard bad things about the plastic ones

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I sure did! Got one thing right at least

He who dares wins

You’ll be okay I’m sure

kermit_rr said:

Hope you ordered one with a metal impeller, heard bad things about the plastic ones

Click to expand...

The metal pump is certainly more robust than the plastic one, but it is also much less efficient at circulating the water at low revs. Noticeable in temperatures over 40 C.

Ok, just thought it nice to post an update. So after my stupidity, I fully expected to be coming back with questions on a engine rebuild, but thankfully, with a new water pump in place, fresh hoses and coolant, it fired back in to life, and seems to be running just like before. It has got a hefty misfire though (new thread to follow )
Anyway, just wanted to say thank you for the encouraging words