Morris Minor Owners Club

Exactly - it's a summer only mod for my Mini - which needs all the cooling help it can get if it's being hard pressed.

bmcecosse wrote:ALEX - if you have managed to get the stub out - seize the chance and plug the wretched hole.

I'm thinking about it - but I'd have to source a suitably sized plug for the head and work out a reliable way to plug up the water pump stub, as opposed to simply screwing the new stub into the head and hooking up the hose.

Some Metro heads come with a plug fitted - eventually it was eliminated completely. And the new pumps come with no bypass connection provision - although older types with connection are of course available too.

bmcecosse wrote:And the new pumps come with no bypass connection provision

I've coincidentally got an unused pump from the junk box that I suspect might be one of these, but the dynamo mounting hole looks to be in a different place (higher up) to that on the old pump. It's hard to be sure if it would fit without taking the old pump off and comparing them side by side. The number cast into the body of it is 12H4488, if that means anything to anyone.

Correction: it actually says 12H4468, which is apparently also known as a GWP130.

I've got the replacement head stub in front of me, but the thread seems unusual - it's 5/8" outer diameter by 16TPI, which doesn't seem to be a standard size as far as I can see from my thread tables. It's made from brass so I'll probably just turn a plug for the hole and braze it in.

rayofleamington wrote: Drilling holes in the stat also makes the car run cooler - not good unless you want to wear gloves in winter.

Most stats I've seen already have a couple of small holes...

You're not looking to bypass the stat bit entirely with holiness, just add a couple to make sure coolant flows a little rather than stalls. Certainly I've never had any problems with cool running from adding a few small holes 3/8 could well be wrong, in fact I think that's the size to drill in Mini air filter housings come to think of it...) when doing away with the bypass on Minis.

But routing the cooling A+ Metro/ Allegro etc style would obviously be the ultimate method, as it clearly worked for production cars

In case anyone's interested, I took my old water pump off and it's rather corroded internally so I'm going to fit a new one regardless. The one from my spares box is a similar design, but the dimensions are all a bit bigger - I reckon it might be from a B series engine. I'm bidding on a new Metro pump on eBay; I'm hoping that'll fit and won't have a bypass stub to mess about blocking off.

My dad says he found a bolt that fit in the hole on the cylinder head and used that to plug it, but I haven't seen what he's done yet.

If you look closely you'll see a little nub on the bottom hose pipe on that water pump. That nub would be a large stump if it had the dratted bypass connection on it, so if you're removing the bypass hose from the system that is indeed the pump you want to use

Bear in mind though you can get brand new over the counter ones for around £15 (sometimes less), so don't get ebay fever going for that one!

Excellent. My maximum bid is below £15