Merak coolant question

[Belfry]

I've just changed the oil and filter on my 1977 Merak SS. Very simple to do.

While I was doing stuff, I added coolant to the coolant reservoir too.

Once I ran the engine to circulate the oil before I checked the oil level, I noticed coolant dripping from the cabin side of the engine, near the water pump.

Luckily my car has an inspection panel between the rear seats. Once I removed this I noticed a small stream of coolant dripping from a small hole manufactured into the engine casing. I attach a photo, does anyone know what this hole is for? What does it do?

The engine is running well BTW.

 

[Oneball]

Id wager your water pump shaft seal has failed.

 

[Belfry]

Can I still drive the car short distances? It's not been overheating.

 

[Oneball]

“Small stream” sounds like quite a big leak to me.

Looking at an engine schematic the problem you could have is that the water pump is driven off the intermediate shaft, so seal failure there could lead to water getting into the crankcase. I’d drain the coolant until you can pull the water pump.

Caveat is I’ve never worked on a Merak but an engine is an engine and they put those holes in water pumps so you get an indication something is wrong.

 

[Belfry]

The oil that I drained was free from any water so I guess that no harm has been done.

 

[Oneball]

If this is the first time you’ve started it in a while it probably wasn’t leaking before.

 

[Oneball]

Part 54 is probably where the leak is


Looks like it has an oil seal as well as a water seal so pretty well designing in case of failure.

 

[Belfry]

Thank you @Oneball. I have asked Eurospares about price and availability. I appreciate your help. I wonder how hard it will be to remove the waterpump?

 

[Oneball]

Somewhere between blimey I didn’t realise it’d be that easy and bloody **** how much is a packet of f@gs these days.

At least it looks like the impeller is keyed and not an interference fit.

 

[Belfry]

So I made a start on removing the water pump. Several hoses of different size secured with jubilee clips. Then two 12mm bolts holding the water pump cover on. First one off then I realised that the second 12mm Bolt was going to foul on the thermostat housing. Several more hoses and 4 hard to reach 10mm bolts to loosen and move the housing enough to get the second bolt out . Oh and of course now that you’ve taken the thermostat housing off you’re going to need to order some new gaskets. I have stopped for the time being while waiting waiting for Eurospares to let me know how long the water pump seal will take to arrive. They are also available for citron that sounds so I might wander into some SM forums if that doesn’t sound too kinky!

 

[RodTungsten]

Try Simply Bearings Up North. Excellent site and helpful staff if you have size and type handy.

 

[Belfry]

I ended up asking McGraths to help, which they did very efficiently.