water pump leakage

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Al Pezzella
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water pump leakage

Post by Al Pezzella » Thu Mar 10, 2011 9:09 pm

I've been working on my water pump leak at the weep hole for a while, first I had the plate behind the impeller machined, did not work,I replaced the plate with a new one because I was afraid that perhaps too much was machined, did not work. replaced the seal, did not work because some suppliers are using a seal that has 18.9mm I.D., too small for the shaft so when I put it back together the impeller forced the seal over the shaft and it cracked. I finally got one that is 19.8mm from GT car parts, it seemed to work when engine was at temperature but once it cooled off it leaked again. Found out that the original spring wire diameter is supposed to be around .26mm well the only ones that are available now are only .19mm, the heavier spring is rated at 45lbs per inch of compression and the .19 is only rated at 15lbs. I installed a .05" shim behind the seal to preload the spring and so far it's holding perfectly.

DWR46
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Re: water pump leakage

Post by DWR46 » Thu Mar 10, 2011 9:17 pm

As you discovered, it is all about the spring tension. We always save the used old style "heavy spring" seals and install the old heavier spring in the new seal. You can also convert the pump seal design to the later Daytona/Boxer design with some machine work. This gives a more reliable sealing system.

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John Vardanian
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Re: water pump leakage

Post by John Vardanian » Sat Mar 12, 2011 3:36 am

Hi Dyke, I am rebuilding my 250 motor and the pump worked fine with no evidence of peeing. Would you rebuild or just paint it and bolt it back? Thanks.

john
PF Coupe

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tyang
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Re: water pump leakage

Post by tyang » Sat Mar 12, 2011 8:28 am

John Vardanian wrote:Hi Dyke, I am rebuilding my 250 motor and the pump worked fine with no evidence of peeing. Would you rebuild or just paint it and bolt it back? Thanks.

john
He's a Ferrari Specialist, not a soothsayer! :)

Tom
'63 330 America #5053

DWR46
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Re: water pump leakage

Post by DWR46 » Sat Mar 12, 2011 10:24 pm

John:

Scott Taylor. a great Ferrari mechanic who is no longer with us, told me years ago "If you go looking for trouble, you will probably find it". As tempting as it may seem to want to rebuild your pump, I would have second thoughts especially if it is working fine. You can always take it off and rebuild it later, as you apparently have already done the hard part in getting the front housing off the studs. On engines that have not been apart for decades, that is usually the hardest part of the job.

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John Vardanian
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Re: water pump leakage

Post by John Vardanian » Sun Mar 13, 2011 2:56 am

Thanks Dyke. I was hoping to hear that, just one less thing to do.

john
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250GT
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Re: water pump leakage

Post by 250GT » Sun Mar 13, 2011 10:11 am

John Vardanian wrote:Thanks Dyke. I was hoping to hear that, just one less thing to do.

john
Everything Dyke tells here is of very high expierance knowledge.
Probebly the best in technicalquestions here.
But I would replace it nevertheless
If a part is not available I would do it like he says
But in this case you can find a new one very easy and cheap
I did a headgasket replacement on the right side see pics.
with compleet cleaning inside of the engine.. a lot of work
I didnot replace that "good" working seal.
after one month there was again water in the oilsump.
or beter say soapgel
My first thought was of coure a bad repair by me ,but that was this time the WP-seal.
its such a trash this soap.

" Neu bleibt treu" or "new parts give confidance/ faith"

C.

Pics of bad quality by iPhone pic from pics
Attachments
IMG_0156.jpg
headgasket repair on one side only.
IMG_0156.jpg (53.17 KiB) Viewed 3502 times
IMG_0150.jpg
WP still in place. a mistake
IMG_0150.jpg (52.45 KiB) Viewed 3502 times

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John Vardanian
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Re: water pump leakage

Post by John Vardanian » Mon Mar 14, 2011 12:42 am

So, then, do I understand it right that if the seal is being repaced one reuses the old spring and all ends up well? Thanks.

john
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250GT
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Re: water pump leakage

Post by 250GT » Mon Mar 14, 2011 1:54 am

John,
Yes thanks to Al P,
The starter of this thread.

whturner
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Re: water pump leakage

Post by whturner » Fri Mar 18, 2011 8:44 pm

Also take a really good look at the rubber bellows! After the replacement in mine was found to be NG we replaced the weak spring with the original spring, but then the rubber bellows developed a leak. A big leak!. I don't know if it was just bad QC, or a design flaw.
By now, I know how to take the water pump out of my Ferrari. Not that it gets any easier with time.

Cheers
Warren
330 GT Series II sn 10069

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John Vardanian
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Re: water pump leakage

Post by John Vardanian » Sat Mar 19, 2011 2:29 am

What are the bellows and where are they located exactly. Would they be in the manual diagrams?

john
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whturner
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Re: water pump leakage

Post by whturner » Sat Mar 19, 2011 11:12 pm

Hi John:

I can't find a picture - nor can I find the discarded one I kept for a memento. Maybe someone on the board can provide one. And I don't know about other Models/Engines. Sorry about that Chief. (to quote Maxwell Smart)
But if you take the pump apart you will not have to look for it. The spring is inside it. It is part of the seal between the back of the impeller and the housing.

Cheers
Warren
330 GT Series II sn 10069

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tyang
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Re: water pump leakage

Post by tyang » Sun Mar 20, 2011 6:54 am

whturner wrote:Hi John:

I can't find a picture - nor can I find the discarded one I kept for a memento. Maybe someone on the board can provide one. And I don't know about other Models/Engines. Sorry about that Chief. (to quote Maxwell Smart)
But if you take the pump apart you will not have to look for it. The spring is inside it. It is part of the seal between the back of the impeller and the housing.

Cheers
Warren
It's all part of the w/p assembly. As the spring compresses against the back of the impeller, the rubber body of the seal flexes. I'll see if I can take a picture of a w/p seal next week.

Tom
'63 330 America #5053

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John Vardanian
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Re: water pump leakage

Post by John Vardanian » Wed Sep 14, 2011 12:46 am

Anyone has a picture of a 250 water pump apart? Thanks.

john
PF Coupe

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tyang
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Re: water pump leakage

Post by tyang » Wed Sep 14, 2011 6:20 am

John Vardanian wrote:Anyone has a picture of a 250 water pump apart? Thanks.

john
Is this what you're looking for John?

Image

Tom
'63 330 America #5053

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