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| | | | Joined: Feb 2003 Posts: 452 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 452 | Help!
I have a Canadian 1949 GMC 3/4T, originally a 216 engine. Cracked head, valves shot, etc, so I sourced a 261. I have the adapter for the 216 water pump, and have drilled and threaded the block for the extra bolts. I have the 216 crank pulley installed as well. The engine has an AC Delco alternator. All the pulleys are aligned.
My problem is the water pump seals keep failing. I'm on my third water pump. Frustration is setting in. Have I missed something? I did notice that the added holes in the block are not into a machined surface, and over tightening there can distort the pump case, so those are just snugged to seat the gasket, no more.
Current fleet (subject to change w/o notice) \'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run. My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787. Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.
| | | | | Joined: Sep 2011 Posts: 1,453 'Bolter | | 'Bolter Joined: Sep 2011 Posts: 1,453 |
BC
1960 Chevy C10 driver 261 T5 4.10 dana 44 power loc
1949 GMC 250 project in waiting
1960 C60 pasture art
Retired GM dealer tech. 1980 - 2022
| | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | I'd suggest doing a little grinding and/or filing on the front surface of the block and adding spacer shims between the pump and the block to prevent any distortion of the pump body while installing it. Hardened steel "Grade 8" flat washers are available in several diameters and thicknesses on Ebay, but you should be sure the block is flat before using them as spacers.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | So you are talking the shaft seal, not the face gasket? Right? I guess it's the shaft seal if you bought 3 pumps. It does seem like you are putting too much pressure from belt as BC said. Orrrrrrrrrrrr..........pump pulley not aligned on same plane a crank pulley....orrrrrrrrrrr a pulley is bent and wobbling a little.
If you are taking them back for warranty, don't do that anymore. Get your money back and buy the next one at a different brand of store. Different brand of pump. Remember what Albert said.
BTW, what is the purpose of the silicone in step 8 of instructions?
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Feb 2003 Posts: 452 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 452 | Yes, the shaft seals.
I didn’t think I had the belt too tight. I can deflect it about 1/2-3/4” between the alternator and the water pump. From what I can see, the pulleys are aligned.
I’ll try a different vendor, and leave the belt a bit looser.
Fingers crossed.
Current fleet (subject to change w/o notice) \'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run. My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787. Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.
| | | | | Joined: Sep 2015 Posts: 81 'Bolter | | 'Bolter Joined: Sep 2015 Posts: 81 | I had this issue when I did the same conversion on my truck. I was able to source a new pump from a Advanced Auto Parts, everyone else had rebuilt pumps and they kept failing. That source may not help you up north but look for the new pump.
Steve
Steve
1946 1/2 ton
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | “ I was able to source a new pump from a Advanced Auto Parts ” Advanced Auto Parts Or ? Advance Auto Parts https://shop.advanceautoparts.com | | | | | Joined: Jul 2000 Posts: 2,188 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,188 | If the pulley is not bent and the belt is aligned properly, is something out of balance?
Gord 🇨🇦
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1954 1/2 ton 235 4 speed
| | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | It would appear that "It ain't rocket surgery" to put two bearings and a seal into a water pump housing and do it right. Since the failure rate is so high on aftermarket pumps, this sounds like a great opportunity for someone to make the initial investment in a few special pullers, etc. to start doing good quality water pump rebuilding.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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