OK so what I have learned so far.......


Change the oil regularly.
don't jump on it out of the hole,
And keep it in the water


Thanks, all 88 Mach 1

Keep it cool-- Add a drive shower!
Keep it stable-- Add external steering!
Keep it lubed-- Use synthetic lube, Amsoil, Royal Purple.
Keep your prop under 30" pitch.

Thanks cobra marty, anything I can do to keep the boat in one piece is good. Was down with an unrelated problem for 6 out of a 9 day vacation, the wife wasn't happy. Thanks again

"Of course, any big power motor will break drive parts sooner than later. Also spinning larger props associated with bigger power motors puts more of a strain on drive parts."

":27'
Deep V
4800 lbs
Mach 1
15 1/4 4 blade 22p "

You sound like you are pretty safe. 22pitch is a small prop. I would assume your engine is quite a bit less than 500HP also if this is all the prop you have. I have rarely heard of Bravo's breaking with mild to moderate prop and HP. Mercury rates them for up to 500HP I believe.

I've got a boat that weighs about the same and has the same power and am running pretty much the same prop. I've never had an issue with my Bravo drive that I didn't cause myself (leave the top vent plug out once and see how long it will run full of water!! :mad: ) But I do NOT do hole shots, and I do NOT over rev it when leaving the water off a swell or boat wake. I also have a drive shower and use Merc. High Performance Gear Lube, changing it about every 20-30 hours.

Oh, and don't hit the bottom either.....stainless props are so strong (oh wait.....Michigan scores AGAIN!!!! Go Blue....42-13)...where was I....Oh yeah...if you hit the bottom hard enough you will break or at least bend the prop shaft, or spin the splines. This is especially true if you have a solid hub prop. Stay off the bottom.

Mike

One thing has been overlooked. If you have separate throttle and shifter, do not shift into gear above 1000 rpm. I lost the upper gears and Merc. would not warrenty saying it was "A high speed shifting error"

Okie Tunnel
 

Okie, Still working on the prop size. Not sure which one to run. As for the HP, it was dynoed at 5200 rpm, 502.35 hp. was running a 3 blade 19 p and turned 5800 rpm now with the 4 blade 22 p can only turn 4200-4400 rpm. Still trying to get the right size prop. May try a 3 blade 25 p. any suggestion?

here is the complete list:

Change the oil regularly.
don't jump on it out of the hole,
And keep it in the water
Keep it cool-- Add a drive shower!
Keep it stable-- Add external steering!
Keep it lubed-- Use synthetic lube, Amsoil, Royal Purple.
Keep your prop under 30" pitch.
do not shift into gear above 1000 rpm


;)

88Mach1, Every 2" prop pitch change is equal to about 400 rpm. So your 19" and 5800prm try a 23" and 5000rpm, A 25" might work if you have the power.

cobra marty
 

I have to power, just need to know, 3 or 4 blade? What I have learned so far is a 4 blade is better out of the hole. Which I don't really need. If I wanna ski, I'll just change the prop. So which one? 3 or 4 blade? Thanks, Mach 1