Welch 1400 leaking vacuum oil. How to fix it?

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davidgrzan
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Welch 1400 leaking vacuum oil. How to fix it?

Post by davidgrzan » Thu Oct 11, 2012 2:25 am

I have just tested the vacuum pump I bought on ebay. It pulls down to 30 Hg which I'm guessing is close to 20 microns (not a good gauge I know). But the pump leaks oil while flinging it into the air as the wheel is spinning. I have found the source of the leakage and I have looked on this forum for problems similar to this but found no luck. I looked at the Welch 1400 manual and it didn't say anything about oil leaking.

Is this a problem any of you have encountered? What do you think would be the cause of this? How can this be fixed?

I have attached some pictures to give you guys a better view.
The leak is located where the metallic part or intake cover chamber meets the pulley.
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bdski
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Re: Welch 1400 leaking vacuum oil. How to fix it?

Post by bdski » Thu Oct 11, 2012 2:32 am

Looks like your shaft seal needs replacement - probably. You can get those on ebay. and they are easy to replace - you'll have to remove your belt, and main pulley, and then remove that older seal - the newer seals are better/beefy'er, and create the actually seal in a different location on the shaft than your existing seal touches. Anyhow - hope this helps ya. Ebay shaft seal, item# 280992584659

Brian

Larry Upjohn
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Re: Welch 1400 leaking vacuum oil. How to fix it?

Post by Larry Upjohn » Fri Oct 12, 2012 8:12 pm

David;
I purchased a much older model of Welch 1400 than yours and it came with the identical leak. I purchased the repair kit from Duniway and it was delivered promptly. I had downloaded the Welch DuoSeal 1400 pump manual and it gives instructions on performing this seal replacement. My pump is now working away reliably when I call upon it with no leaks at all. These pumps are well worth the rebuild as they are very soundly designed and assembled. Best wishes, Larry Upjohn.

P.S. I believe that Duniway offers 3 levels of kits for rebuilding the pump and I purchased the mid level kit at around 60.00 USD.
Larry Upjohn

davidgrzan
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Re: Welch 1400 leaking vacuum oil. How to fix it?

Post by davidgrzan » Fri Oct 12, 2012 8:17 pm

Yes thank you guys for the responses. I bought the shaft seal replacement on eBay but before that I took the pulley apart to make sure it was the source of the leak. The original seal had been bent so I think that is why it was leaking.

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