Bringing a 740 back to life

[Laird Scooby]

Don't forget the silicone grease on the "O" ring, seal and gasket too!

[Ian21401]

Originally Posted by 360beast

I believe he is talking about the four studs on the front of the pump to hold the pulley on to the pump.

Doh. I’d forgotten about them.

[Challo]

Sorry for the poor explanation guys, yep I did mean the four studs at the front the fan attaches too. Got them all switched over which is good, just can’t get the bloody pump off.

All the nuts and bolts have been undone and removed and the pump will wiggle but won’t remove. I think the rear pipe is still stuck in postion. I don’t want to force anything, but is there a way to remove the rear pipe. The bolt has been undone and removed.

The leak is definitely coming from the top o ring as it looks like it has disintegrated.

[360beast]

As the pump is being swapped a little bit of love with a hammer should get it off, removing that hard coolant pipe is a pain as it goes to the back of the engine and has a heater valve pipe on it which will probably be very hard to access down the back of the engine and it will probably be well and truly stuck to the heater valve outlet on the bulkhead and will end up needing to be cut off, if you have some decent adjustable grips you could try and twist it off with those.

I would recommend trying the tickling stick first and if it doesn't budge then try using a pry bar at the same time against the ribbed section of the waterpump and the cylinder head and if that doesn't work then I'd be looking in to heating the pump up around that area as taking the hard pipe off should be a last resort. Try soaking it in some wd40 or Dave's WMP (50/50 nail varnish remover and synthetic ATF) overnight and see if it makes a difference, the end of the hard pipe might have rusted solid or have a lot of old dried coolant holding it tight to the waterpump.

Just to double check, you have removed the nut and bolt that goes through the waterpump to the hardpipe? I know you have wrote the bolt has been removed but I just want to double check that's the one you are talking about.

[Ian21401]

I’m not trying to insult your intelligence here but, does that pipe on your car have a small steel bracket underneath, right next to where it enters the water pump, with a bolt securing it to the water pump body? It is not easily visible unless you are actually looking for it. If yours has one and you have removed it then I can only suggest some very careful wiggling to free the pipe from the pump. Releasing fluid may help. It may be that the “O” ring has perished and welded itself to the pipe and pump body.


Sorry, I hadn’t seen Luke’s above post as I had gone to have look at my car.

[Challo]

Originally Posted by Ian21401

I’m not trying to insult your intelligence here but, does that pipe on your car have a small steel bracket underneath, right next to where it enters the water pump, with a bolt securing it to the water pump body? It is not easily visible unless you are actually looking for it. If yours has one and you have removed it then I can only suggest some very careful wiggling to free the pipe from the pump. Releasing fluid may help. It may be that the “O” ring has perished and welded itself to the pipe and pump body.


Sorry, I hadn’t seen Luke’s above post as I had gone to have look at my car.

Yep that nut and bolt has been removed. Missed it at first, but then realised it had to be removed as well.

As Luke mentions I’ll get the hammer out and tease it off. I think that O ring has welded on.

[Ian21401]

Don’t go too mad with the hammer as you don’t want to have to replace the pipe as well.
Good luck.

[Laird Scooby]

If the rest of the pump is loose Chris, try wiggling it around the pipe/"O" ring to help break the seal while pulling towards the front of the car but not too hard in case it suddenly comes free - you don't want to put a water pump shaped hole in your radiator!

[360beast]

It would be worth putting a few sheets of thick cardboard in front of the radiator, a few seconds spent on preventing damage will be a much better way to spend your time than finding a new radiator!

[Challo]

Still no luck at the moment. Plenty of WD40 sprayed last night and today and still won’t budge. Limited access to get a hammer in, but tried a few taps and nothing. I’ll dig out the heat over the weekend and see how that goes. It’s definitely stuck on that bloody pipe.

In the meantime the odometer was removed and checked why the Speedo doesn’t work but the Rev counter does. Thought it was the broken plastic gearing, but that looks fine. All put back together and I’ll get it reinstalled and see if that fixes it.

Why did I bloody decide to work on a 30year Volvo. Becoming a pain the neck. 😂