Author Topic: 1968 Z28 water pump bypass fitting  (Read 9048 times)

z28z11

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1968 Z28 water pump bypass fitting
« on: August 25, 2018, 07:29:11 PM »
I've searched the threads and never found a "definitive" answer - is the hex style fitting or the square style proper for a June '68 Z28 326 water pump bypass hose fitting ? I have a 1/2" NPT GM NOS square style fitting, but afraid it was released as a replacement or maybe was used on L79 motors prior to '67-'68 MO applications. Opinions ?

Regards,
Steve
1968 Z28 M21/U17 BRG/W 1967 Chevy ll Nova SS 
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06  1949 3100 5wd 235/6

luv2sixty9

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Re: 1968 Z28 water pump bypass fitting
« Reply #1 on: August 25, 2018, 10:46:56 PM »
Hex
1967 Z/28 Butternut Yellow
1969 Z/28 Rally Green
1969 RS Z/28 Lemans Blue
1969 RS Z/28 Olympic Gold
1969 RS SS Pace Car
2010 Aqua Blue 2SS RS

68camaroz28

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Re: 1968 Z28 water pump bypass fitting
« Reply #2 on: August 25, 2018, 11:49:43 PM »
Hex
X2 on hex but limited originals observed but believe that to be what is considered technically correct. Here is an original with stampings.


Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584

z28z11

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Re: 1968 Z28 water pump bypass fitting
« Reply #3 on: August 26, 2018, 06:57:23 PM »
Here's what threw me - correct part number in my early 70's part book, 3829819, NOS, but apparently superseded the hex with the square. Disappointing due to a good looking part !

Thanks for the replies and the confirmation -

Steve
1968 Z28 M21/U17 BRG/W 1967 Chevy ll Nova SS 
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06  1949 3100 5wd 235/6

169INDY

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Re: 1968 Z28 water pump bypass fitting
« Reply #4 on: August 27, 2018, 03:01:51 AM »
Hex
Jim
68 SS/RS L35 Th-400 LOS
69 Pace Car L48 Th-350 LOS
68 Z28 M21 LOS


dannystarr

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Re: 1968 Z28 water pump bypass fitting
« Reply #6 on: August 27, 2018, 04:18:15 PM »
Hex has a better visual..  ;D  Gotta be SOMEONE here with an extra original one for you. Let me go look in my stuff... Danny

dannystarr

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Re: 1968 Z28 water pump bypass fitting
« Reply #7 on: August 27, 2018, 04:32:43 PM »
I found one.. It's a little tired. Is this correct? Has different markings, but maybe a different vendor?  Danny

dannystarr

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Re: 1968 Z28 water pump bypass fitting
« Reply #8 on: August 27, 2018, 04:33:26 PM »
more

dutch

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Re: 1968 Z28 water pump bypass fitting
« Reply #9 on: August 27, 2018, 06:25:17 PM »
Sort of 'off topic' but sort of not..  What really does a bypass fitting do other than bypass coolant directly to the intake and avoid the heater core hoses and circuit?
Do they really serve great and needed purpose(s) for engines and if so why were they not installed on all engines and not just the HiPerf versions like the Z's and L78's? Was there something to do with the higher rpm's that these engines were capable of that make their installation a necessity verses regular lower rpm versions.. there should be some logical reason I'm not aware of?
I do know GM made many other good performance engines that rev'd up well that didn't seem to need such an arrangement so..?

z28z11

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Re: 1968 Z28 water pump bypass fitting
« Reply #10 on: August 29, 2018, 01:14:12 AM »
more
I found one.. It's a little tired. Is this correct? Has different markings, but maybe a different vendor?  Danny

Looks like it to me. The two (or more) vendors for any particular part is perfectly plausible - we've noted that fact on many other parts.

This one appears to have been painted at one point in time - wonder if that was original ? By the looks of the hose end, it was in service for a long time - you don't get pitting like that on a plated steel part in a couple of month's exposure.

Regards,
Steve
1968 Z28 M21/U17 BRG/W 1967 Chevy ll Nova SS 
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06  1949 3100 5wd 235/6

68camaroz28

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Re: 1968 Z28 water pump bypass fitting
« Reply #11 on: September 04, 2018, 01:03:10 PM »
more
I found one.. It's a little tired. Is this correct? Has different markings, but maybe a different vendor?  Danny

Looks like it to me. The two (or more) vendors for any particular part is perfectly plausible - we've noted that fact on many other parts.

This one appears to have been painted at one point in time - wonder if that was original ? By the looks of the hose end, it was in service for a long time - you don't get pitting like that on a plated steel part in a couple of month's exposure.

Regards,
Steve
That coupling, hose and clamps were on z/28 engine when painted.
Chick
68 Z/28 NOR 01B Orig motor/trans/rear
69 Z/28 NOR 07A Orig Block & GM Cross-ram/carbs
69 L34 Rest. Nova Father/Son Car
69 L78 Surv Nova Purch 4/69 31K miles
67 L89 Corv Tribute
68 Corv 427/400 Orig motor
07 Corv Z06
R 68Z build- http://www.camaros.net/forums/showthread.php?t=182584

luv2sixty9

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Re: 1968 Z28 water pump bypass fitting
« Reply #12 on: September 09, 2018, 05:13:08 PM »
Here is yet another one, making it (3) different markings. I also have two NOS ones with no markings at all.

Mine has what appears to be "CP" within the diamonds and a circle around the diamond.
1967 Z/28 Butternut Yellow
1969 Z/28 Rally Green
1969 RS Z/28 Lemans Blue
1969 RS Z/28 Olympic Gold
1969 RS SS Pace Car
2010 Aqua Blue 2SS RS

Tx-Z 302

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Re: 1968 Z28 water pump bypass fitting
« Reply #13 on: September 09, 2018, 07:19:14 PM »
I'm in the market for one of these!
Chris W

dannystarr

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Re: 1968 Z28 water pump bypass fitting
« Reply #14 on: September 10, 2018, 03:26:47 AM »
Z28Z11, you still need one of these? Maybe might be better to start off with a fresh new one. Unless your car is ALL numbers matching/survivor. Then you surely don't want a new one  ;D  Danny