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Ive tried fitting a second water pump as my last one was leaking and the bearing was shot, but the new (second hand) is leaking too. The bearings are good in this one, so it looks like its just the seal that need replacing.

Has anyone changed the seal for a rotary seal kind of like this, with any success?



I know somerfords sell the replacement seal but I need to have it running by Sunday! Also am I correct in thinking that the original seal actually seals on the back face of the impeller? If so this could be more of a reason to change it as I can't believe the original type would last too long, as I guess the impeller sealing face won't be as smooth as it should be due to corrosion/wear over the years.

Cheers
Matt

Hi Matty,
I have successfully rebuilt some cast pumps down here in NZ. I fit a stainless steel unit seal that fits straight into the housing and the other half seals on the shaft, no longer bearing on the impeller face. The only modification needed is to turn some material off the impeller to make room. A special pressing dolly is needed to achieve the correct compression of the seal spring and I turned one from a piece of nylon stock. It works well and should last for many years, way longer than the original setup.

Regards
Al

Thanks for the reply. But by a stroke of luck ive sorted it!

I bought a cast ally pump today, to fit for the time being...but then I decided to take it apart to see what those internals are like.

It turns out that the internals of a later pump will acutally fit in the cast iron pumps with no modifications needed!

Hi Matty,
The seal you show is pretty much the same as the ones I use. Glad to know you have it sorted.

Al

It sure does, I had to press it on to the shaft an extra 5mm than when it was on the ally housing though.

exceeelllent ... more flow for when the turbo goes on .

Haha, ive only done about 50 miles in it, and already had thoughts of doing a retro super charger or something.

I was also wondering if it would be possible to turbo, but keep it looking stock. eg keep the 1 1/4 su and some how make the original air filter box sealed,and boost it through there and use that as kind of a plenum with the restricter ring in...Im getting my TIG next week, so I need an excuse to use it. lol

hi matty came across your interesting article ,could you tell me the make of alloy pump you used,had a go myself with a first line part and the impeller fouls on the block, and also when completed does the pulley run inline with other pulleys? thanks

I can't remeber off hand what the make was. I'll have a look in the garage to see if ive still got the box though when I get home.

Luckily I had a second pump to measure off to get the pulley drive flange in the right location.
The impeller I just pressed on until it had about a 0.5-1mm clearance on the pump casting. The impeller was pressed on to the shaft a good 5mm further than when I bought it, so if you haven't pressed it on further it would foul the block.

Without the gasket in place you could hear the impeller very slitghtly skimming the block, so it is critical to get the impeller as close to the casting as possible!