Hey swabs,
Just picked up a couple of M77HV pumps for the 496 strokers in my Maxxum 281, and need some advice.
Yes, I've cleaned up the in and out ports to eliminate burrs, etc.
The shop that did the bottom end tell me they pack these pumps with white grease before they install-makes them last longer, however, I've read this is not a good idea.??
I'm also looking for some pickup tubes, or should I use the stock? I've measure and they are the same size, leaving .475" between screen and pan....any opinions out there?

Thanks,

I always take the pumps apart and check the clearances and block the cover smooth. They are rough as hell out of the box. I also rerouted my oil bypass back to the pan. Tap and plug the internal ports and drill the outer cover with two 1/4" holes. This keeps the oil from heating and aerating in the pump. Sorry I don't have pics.

Thx Kennyo, that's the first time i've heard of rerouting the oil bypass - interesting, but I'd need to research more before going that route.

I just buy the pumps from System one and lube with amsoil severe duty gear oil then install

Ive only put oil or Clevitte bearring asmy lube in the pump,150hours 850+hp no probs.


here some stuff I did,deburing is good
http://www.offshoreonly.com/forums/s...=500efi&page=4


also mesure the depth of the oil pan, Moroso makes a good pickup and its cheap,I think mine was a 8 inch.They make a better pump than the M77,It doent have powered metal gears, i think theres some info in my thread,or do a search on oil pumps,hope this helps,Rob

Return those M77HV and purchase the Melling Select 10777C pumps and you can quit playing with oil pumps, do not change the pressure spring they come with! There is more power and reliability to be found other places in your motors, go there!

Best Regards,
Ray @ Raylar

This was my first experience with Active Performance(built Snap-On tools APBA boat), and never heard of packing the pump with white lithium before install.

Geez, thanks for the link - lot of good info, esp the tig welding warning - is there another way to ensure the press-fit pickup doesn't come loose? Is there no adhesive approved for the purpose?

Yeah, I like the aftermarket bolt-on pickups but, can't wait two weeks to get them here so I'm gonn reuse the stock-I measured the pans and they're 8.5" - thx for the help, Rob.

Good advice, Ray, and can't figure out why Mike at Active ordered me the 77HV when there is a better product out there for minimal increase in cost. You're right, better to spend the effort somewhere else. ((Interesting point on the "C" - anticavitation feature providing low idle press. in Rob's post link)

Here's a pic of the lake from yesterday - water is till a bit hard!