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Midget 1500 Water Pump / Fan Clutch Question

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A few weeks ago I had a failure of my fan clutch, torerance ring, or water pump and the plastic fan the fan clutch went into the radiator. I posted this after it happened.

I now have a new water pump, fan clutch, tolerance ring, & plastic fan. I went to install the fan clutch onto the water pump and I found a difference between the old water pump and the new water pump. With the tolerance ring removed I can press on the new fan clutch onto the old water pump shaft with no pressure required. Is this normal? With the tolerance ring removed I cannot press the new fan clutch onto the new water pump. Is this correct? I don't know if the tight fit between the new fan clutch and new water pump is normal. Is there anyone out there who has replaced the water pump on a 1500 Midget? I would like to know if the fan clutch needs to be pressed onto the water pump shaft regardless of the tolerance ring. Thanks in advance for any help provided.
 
Hi Tony, the tolerance ring is needed to hold the fan clutch to the pump. If you got the pump from Victoria British, it should have come with the ring installed. I changed mine earlier this year and it came with one anyway. I used a big C-clamp to press it on, but you are correct, it will be a loose fit withoout the ring. Hope this helps!
 
Sparkydave,
Do you remember if the fan clutch had to be pressed onto the water pump shaft before it got to the tolerance ring? That is the question I have. My new clutch fits right over the old water pump shaft (with tolerance ring removed) without any pressure at all. I cannot press the new clutch onto the new water pump at all. I will need to press it on. Is that what you found on your parts?
 
ok, as i read your post, i get the idea that your NEW pump shaft is larger than your Old one? can you measure them, Preferably with a pair of calipers, and post what sizes they are? can you measure the ID of both the old and the new clutch? as well as the thickness of the tolerance ring. Wether or not you need the tolerance ring will be determined by these measurements. I would think that you would be looking for about a .001-.0015 press fit. Or as sparkydave says perhaps the ring is already on the pump, or in the clutch.


mark

mark
 
Ah, that is a bit different. I don't think it was a tight fit on the end of the water pump shaft. It may have been close enough that you might have to squeeze it with your fingers to slip it on the shaft, but it seems to me most of the interference fit was from the tolerance ring, hence the need to press the fan clutch on. I can't remember if the fan clutch came from VB, but if it did it was bought a few years before the water pump. I can safely say the replacement water pump had the same kind of fit as the original though, because I replaced the worn out fan clutch when I was getting it back on the road, but the water pump seal finally let go this year.
 
I replaced my water pump and fan clutch assembly this summer with parts from VB. It was a tight fit all the way from the start when placing the new clutch on the pump. It was well over 100 degrees on project day and I think I lost 5 pounds. I love chocolate milk.
 
Phireman has emailed me and what I am seeing with the new parts vs what he saw are the same. I can only conclude that my old fan clutch was spinning around on my old water pump shaft and wore down the shaft. Then the fan clutch and fan went forward into the radiator. I thought that the only failed part was the fan clutch but the water pump is also bad since the shaft has been ground down by the fan clutch. I will get my new fan clutch pressed onto my new water pump (with new tolerance ring) and that should fix my problem. Thanks everyone for your assistance - especially Phireman.
 
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