reliability GM ZZ502-502 HP GM CRATE ENGINE
07-11-2006 | 08:38 AM
#11
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From: Cape Coral, Florida
Re: reliability GM ZZ502-502 HP GM CRATE ENGINE
Originally Posted by Kidnova
I'm starting my 4th season with the ZZ502/502. Other than oil temp issues covered in the above paragraph/s, to date the engine has run flawlessly and has always been dependable.
Bill
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07-11-2006 | 09:45 AM
#12
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From: 29°50'49.74"N 95° 5'17.55"W.......TEXAS
Re: reliability GM ZZ502-502 HP GM CRATE ENGINE
Originally Posted by Kidnova
Hey Jeff32 -
After some running time and 3 oil coolers later, I finally figured out that the center bypass valve in the engine oil pad needs to be removed. And the bypass valve on the side of the pad needs to be changed from a +,- 30 lb. to a +,- 11 lb. (The "lb" reference may not be correct but if you need more on this let me know and I'll see if I can dig out the info).
After some running time and 3 oil coolers later, I finally figured out that the center bypass valve in the engine oil pad needs to be removed. And the bypass valve on the side of the pad needs to be changed from a +,- 30 lb. to a +,- 11 lb. (The "lb" reference may not be correct but if you need more on this let me know and I'll see if I can dig out the info).
07-11-2006 | 09:48 AM
#13
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From: 29°50'49.74"N 95° 5'17.55"W.......TEXAS
Re: reliability GM ZZ502-502 HP GM CRATE ENGINE
This thread should be required reading for anyone upgrading power or experiencing oil pressure/temp issues 
http://www.offshoreonly.com/forums/s...d.php?t=106633
http://www.offshoreonly.com/forums/s...d.php?t=106633
07-11-2006 | 09:54 AM
#14
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From: central NY
Re: reliability GM ZZ502-502 HP GM CRATE ENGINE
Originally Posted by Wobble
Kid I know you meant to say that you replaced the 11pound bypass valve to the 30lb one spec-ed for external filter/cooler
Wobble - Thanks for the correction. Hence my little disclaimer in (***) after refering to the bypass valve....senior moment perhaps?
07-11-2006 | 09:56 AM
#15
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From: central NY
Re: reliability GM ZZ502-502 HP GM CRATE ENGINE
Originally Posted by Wobble
This thread should be required reading for anyone upgrading power or experiencing oil pressure/temp issues
http://www.offshoreonly.com/forums/s...d.php?t=106633
http://www.offshoreonly.com/forums/s...d.php?t=106633
07-11-2006 | 10:04 AM
#16
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From: 29°50'49.74"N 95° 5'17.55"W.......TEXAS
Re: reliability GM ZZ502-502 HP GM CRATE ENGINE
Originally Posted by Kidnova
I know you knew that...I know you knew I knew....you know....ah fuggit
Wobble - Thanks for the correction. Hence my little disclaimer in (***) after refering to the bypass valve....senior moment perhaps?
Wobble - Thanks for the correction. Hence my little disclaimer in (***) after refering to the bypass valve....senior moment perhaps?
09-10-2016 | 01:08 AM
#18
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From: Western N.Y.
I'm pretty sure they had issues. I don't remember that ending well. I think there is a thread in the Scarab section with someone having good luck with the GM crate motors. I forgot which though, might be the 572s.
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09-10-2016 | 07:25 AM
#19
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From: Prescott, Ontario
I had been thinking of putting that exact motor in my 22 SCARAB, because GM stated in their performance catalogue that this engine was suppose to be good for marine use. I called an excellent engine builder in our area, to get his thoughts and opinion, and his answer was, if you want to see what happens when you put that engine in a boat, come out here and have a look at the 2 I have sitting here. He said some guy tried to re-power a 34' BAJA with 2 of those, and they both broke within 20 hours.
That made my decision very easy, and I left the stock 350 in my SCARAB.
That made my decision very easy, and I left the stock 350 in my SCARAB.
09-10-2016 | 07:30 AM
#20
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From: St-Hyacinthe, quebec, canada
It is clearly written black on white in that performance catalogue NOT INTENDED FOR MARINE USE !
No where is written they are ok... Wondering where you saw that i have one of each year for the past like 15 years!
No where is written they are ok... Wondering where you saw that i have one of each year for the past like 15 years!
