HEEEELP! Is my cage haunted? Mechanical opinions needed.

**CookMySock** · 11th April 2010, 08:25

As above, but first check you don't have a cylinder head gasket leak. That will pressurise the cooling system and rip it apart. Get a mechanic to test the radiator water for combustion gases.

Steve

**peasea** · 11th April 2010, 09:17

Originally Posted by Hans

The wife's car grenaded itself in a most spectacular fashion yesterday evening.
The whole cooling system has failed in a way I have never seen before.
There are leaks just at just about every hose connection. Coolant is pissing out of the bottom of the water pump and out of a hole in the housing. The hole is circular, about 3mm in diameter and looks as if it was there before, but has no thread in it. The drain plug in a metal pipe at the very bottom of the system fell out when I touched it. The screw looks freshly corroded away, heaps of fine pitting and a bright metal surface.

What the fuck is going here? I serviced the cooling system about 8 months ago, put in demineralised water and inhibitor of a compatible type. It looks like the whole system received a huge amount of hydraulic shock. The radiator cap shows no signs of having released any overpressure, but appears functional. Any ideas how, why?

I am now facing 50hrs plus of labour to get the thing up and running. I am well and truly fucked.

BTW the car is an sw20 Toyota MR2.

I did many years with Toyota and this is my take on it.

Your alternator died and was rebuilt, right? I would guess that the bearings in your water pump have done many thousands of k's and when the alternator was refitted the multi-v belt was over-tightened. (This is more common than you think.) The extra tesnion pulling the water pump bearing off-centre has finished off the bearing and/or seal in the water pump. Coolant has oozed from the tell-tale hole (the 3mm hole you describe, which is indeed put there by the factory) and the engine has overheated. The steam in the cooling system has over-pressurised the system and forced remaining coolant from any weak point.

It's possible it's puckerood thanks to the overheating but it depends entirely on how seriously it has overheated. Often it looks worse than it is, often with coolant hitting a hot exhaust, steaming away furiously and stinking the place up. Is there any sign of water/condensation in the oil? (On the underside of the oil filler cap or on the dipstick?) If so, I would be inclined to drain the oil and look for more water/coolant. If there is water in the oil you've probably got a mare, if not I'd be inclined to whack a water pump on it, pressure test the cooling system and drive on.

Something you can do to check the head gasket's integrity is to perform a cylinder leak-down test, you might want to talk to your spanner man if you don't know what that is and he should have the required nouse and equipment.

Your two biggest problems would be a blown head gasket or even a split head (the latter is rare on those motors) but at best a new water pump and the aforementioned cooling system pressure test should see you back on the road.

Any more questions about Toyotas don't hesitate to PM me.
Good luck.

**mdnzz** · 11th April 2010, 09:42

I'll concur with Peasea, if you got one with the 3s-ge engine then I have seen a failure like this before first hand. Replaced faulty alternator on an engine that had done 170,000ks 3 weeks later major looking blow out of coolant system. Turns out to be what Peasea described, pump had failed, fail safes went and over pressurised. New water pump, refitted new hoses cap etc and tested. Did an oil change and checked no obvious signs, drove the car for another 60,000 before selling to some young fella few years back.

**Hans** · 11th April 2010, 10:27

Originally Posted by mdnzz

I'll concur with Peasea, if you got one with the 3s-ge engine then I have seen a failure like this before first hand. Replaced faulty alternator on an engine that had done 170,000ks 3 weeks later major looking blow out of coolant system. Turns out to be what Peasea described, pump had failed, fail safes went and over pressurised. New water pump, refitted new hoses cap etc and tested. Did an oil change and checked no obvious signs, drove the car for another 60,000 before selling to some young fella few years back.

Yep. 3sg-e. An it sounds exactly like what you're describing. That was the one time I let someone else do anything on the car. The one last time. Fuckwits. ANyway, I've got the factory workshop manual, so I've got some pointers. Cambelt was due anyway, and I guess I can just eat dirt for the next three weeks. Fuck.
Thanks again, I'll report on findings when I'm done in the evening.

**Mully** · 11th April 2010, 11:05

Nope - all wrong.

It's clearly goblins.

Did you see anyone like this around your car??

**Hans** · 11th April 2010, 12:27

Well, it turns out that the water pump is not belt driven. So that's not what caused it.

**peasea** · 11th April 2010, 12:35

Originally Posted by Hans

Well, it turns out that the water pump is not belt driven. So that's not what caused it.

The water pump on a 3S-GE isn't belt driven??

**steve_t** · 11th April 2010, 12:38

Originally Posted by Hans

Well, it turns out that the water pump is not belt driven. So that's not what caused it.

Are you sure? Or has a previous owner replaced the OEM unit with an electric one?

Edit: Beaten to the punch by peasea

**Hans** · 11th April 2010, 12:38

Originally Posted by peasea

The water pump on a 3S-GE isn't belt driven??

Nope. It must run of the engine. I've removed 2 accessory belts. One drives the alternator and one drives the aircon compressor. And that's it.

**Hans** · 11th April 2010, 12:40

Originally Posted by steve_t

Are you sure? Or has a previous owner replaced the OEM unit with an electric one?

Edit: Beaten to the punch by peasea

Positive. 10 char.

**Hans** · 11th April 2010, 12:43

Ok, not so positive. It isn't driven directlly off the engine. It's Driven by the timing belt. That's what the workshop manual says. And that's why the timing belt has to come off to remove the water pump. Fuck.

**Mully** · 11th April 2010, 12:47

Originally Posted by Hans

Ok, not so positive. It isn't driven directlly off the engine. It's Driven by the timing belt. That's what the workshop manual says. And that's why the timing belt has to come off to remove the water pump. Fuck.

I thought most were driven from the timing belt. It's why you generally change cambelt, tensioners and water pump all at once.

When's your cambelt due? If you've got to take it off, you might as well replace it with a new one.

**Hans** · 11th April 2010, 12:49

Originally Posted by Mully

I thought most were driven from the timing belt. It's why you generally change cambelt, tensioners and water pump all at once.

When's your cambelt due? If you've got to take it off, you might as well replace it with a new one.

Yep, due soon. I will change it while I'm in there. If I ever manage to get to it, that is. The Tbelt cover is obscured by a mounting bracket and I can't for the life of me get to the three bolts that hold it. Right now, I'm wondering wtf I've got myself into.

**peasea** · 11th April 2010, 12:55

Originally Posted by Hans

Yep, due soon. I will change it while I'm in there. If I ever manage to get to it, that is. The Tbelt cover is obscured by a mounting bracket and I can't for the life of me get to the three bolts that hold it. Right now, I'm wondering wtf I've got myself into.

If you're talking about the upper engine mount then don't forget to put a jack (with a block of wood on it) under the sump. Usually there are nuts or bolts that are only accessable from underneath with a long extension. From memory there might be one large bolt that runs through the mount but the actual mount needs to be removed also. Take the top cam belt cover off (some bolts are a bit tight to access, quarter-drive socket set is handy here) and you'll probably see what I'm on about.