LLY Water Pump
- Thread starter mattv
- Start date
Yes you'll never EVER have to worry about the impeller spinning on the shaft. Only way to go when replacing a water pump in my opinion, but what do I know I'm just a dumb 23 year old!
Several things come to mind, the stock maximum RPM is 3250 IIRC so reving further than that will do some damage to a component meant to sustain a working RPM of about 2200rpm at the crank as these are working engines and transmissions designed for long term sustained pulling/driving not necessarily for stop, start, go, race 15 minute trip daily driver trucks to and from work.
The welded pump might be of concern as the pump is a direct drive from the camshaft gear and the vibration , sudden rpm changes could very well crack the welds over time and spin the impeller on the shaft, a pinned pump for what you're doing is a cost well spent...
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The welded pump might be of concern as the pump is a direct drive from the camshaft gear and the vibration , sudden rpm changes could very well crack the welds over time and spin the impeller on the shaft, a pinned pump for what you're doing is a cost well spent...
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I cheaped out and bought a stock replacement thinking I wasn't pushing enough power. About 2 months later I spun the impeller off, overheated, and popped the head gaskets. Most expensive cheap water pump I've ever bought.
Thanks for the info about welded pump shafts, I was thinking about buying one for a spare since I pull a fifth wheel across the country, but I'll get a pinned one instead. Now you've got me worried, my truck sees 4KRPM+ all the time descending steep hills and I still have the original pump, prolly not good for it....!?Several things come to mind, the stock maximum RPM is 3250 IIRC so reving further than that will do some damage to a component meant to sustain a working RPM of about 2200rpm at the crank as these are working engines and transmissions designed for long term sustained pulling/driving not necessarily for stop, start, go, race 15 minute trip daily driver trucks to and from work.
The welded pump might be of concern as the pump is a direct drive from the camshaft gear and the vibration , sudden rpm changes could very well crack the welds over time and spin the impeller on the shaft, a pinned pump for what you're doing is a cost well spent...
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I don't think deceleration is the problem, acceleration with the RPM limiter changed via EFI to 4000rpm or more might be the problem.?
I never had a issue with my stock Lbz pump. Reinstalled on rebuild at 30k area and was still kicking at 112k.
I have sold a lot of the merchant welded hybrids pump with no issues. They also come with a lifetime warranty.
I have sold a lot of the merchant welded hybrids pump with no issues. They also come with a lifetime warranty.
3250 rpm????
they'll easily do 4500rpm under grade braking conditions, stock..........
I think its more the rapid acceleration with high HP that hurts them....not just RPM per se.
Does the above highlighted cover it, I guess I should have explained it more thoroughly.
