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COOL CROSSBOW
05-15-2009, 01:17 AM
The CROSSBOW is finished! It only took from Sept. to May to rebuild the 502's and to stroke them to 540's. While i was handling the engines, Brody came and picked the boat up from my shop in MS and took it back to Dallas to update the engine bay. I want to thank everyone for thier help and having faith that a car guy can learn to work on a boat with the right teachers. I must thank Bob at Marine cams, i told him everything the customer wanted and he picked out the best cams for these engines cause ive been on Lake Lewisville in Dallas for the past three days breaking them in then. I turned it over to Brody, the owner, and the first thing he did was see how fast it would go. Ive been listening to these 540's screaming at 5800rpms for hours and it dosent take long to burn 150 gal of fuel out at that speed. There is something we cant figure out?! mabey you guys could tell me whats wrong. The out drives (TRS) will trim in and out at low speed just over idle, or cruising speed, but when you are trying to trim it out, to get your best mph, the out drives will not move out. I dont know enough about this right now, so it seems as if the trim pumps arent strong enough to push them out at speed. So they stay tucked under or down which keeps the nose from coming up. Even so we were able to reach 72mph at 5800rpm with #23 three blade props (on my gps which was within 2 mph with the dash speedo) and about half tank of fuel and with three guys on board. This guy wants his crossbow to go 80mph at 5800rpms any suggestions. I have lots of picks and videos of the restoration. i'll post some highlights when i can. :popcorn:

MOP
05-15-2009, 08:36 AM
At 5,800 good chance you will be eating some outdrives, IMO you can do what you want a lower RPM"s. The few 540's that I have been around have more then enough snot to get you to 80, try to get there @ 51-52+ but not 5,800 the drives just don't last up there.

The Hedgehog
05-17-2009, 06:14 PM
You may want to play around with the lowers. There is a guy here that has some Speedmasters on his and he is well into the 80's

COOL CROSSBOW
05-21-2009, 09:53 AM
Cool Thanks, We did find air in the trim pump lines, since having them off the boat. We'll try again this weekend.

Alan

BigGrizzly
05-21-2009, 11:54 AM
You may have the lines backwards on one or both. 2000 psi one way 600psi the other. The original TRS pump is the strongest in the industry. Remember that pump is slow too.

BUIZILLA
05-21-2009, 12:00 PM
I'd MUCH rather turn a TRS 5800 than a Bravo

but, that's just me :popcorn:

mphatc
05-21-2009, 06:10 PM
Guys,

You want your drives to last . . change the fluid to Redline LTW Shockproof .. & change it annually!
I'll bet the TRS drives can easily handle 540s at 5800 RPM on a lake, jumping waves is another story!

Mario L.