Blow Out

[BEEZER]

Any of you guys had any experience dealing with blowing out at high speeds? If so, how did you deal with it and what was cause and cure?

[Basswipe]

Is it blowing out because you hit the trim button one too many times on a speed prop that loses bite? Or is it more of a "lower unit that can't handle the speed" blowout?

[BEEZER]

I'm actually not the one with the blowout problem.The guy has a 202 with stock lower unit bob's nose cone. From his discription it always happens on the trim, (one too many bumps up) is how he explained it. The only time I've had a problem was trying out a Tempest and it let go at 80 and I took it off and gave it back to the person I borrowed it from. I'm just wanting to learn more about what causes it and how to get it out. His boat seems to blowout no matter what prop or what lower unit he runs.

[Basswipe]

Now that’s weird, I've never heard of a boat that blows out with any prop or any lower unit. Now, does it blow out at any motor height??

I would guess that since it’s kind of widely known that a Blazer will drop it’s nose when trimmed too high that it might be more of the motor is too high to run the props he’s running and he may need to lower it even though his water pressure is still high enough to support the motor running at it’s present height. That’s my guess. Is he running his motor pretty high?

[GE Blazer]

Have him to check his torque tab. Mine use to do it at 87 every time.

[BEEZER]

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GE Blazer &raquo;</TD></TR><TR><TD CLASS="quote">Have him to check his torque tab. Mine use to do it at 87 every time.</TD></TR></TABLE>

GE. It's a merc promax without a torque tab stock 200 LU Bobs cone. He runs most of the time 1/4 inch above the pad give or take a 1/4 inch depending on the prop. Last weekend he tested 5 or 6 props including mine and they would all trim to a point where he felt like the boat was about to turn around. could threre be an air pocket that increases with speed and trim allows it to reach the exaust.
GE did you figure out anything to fix your problem?
I kinda think its some sort of set up issue but if he lowers the motor even one click he looses speed.
Maybe I'm thinking backwards and he needs to go up and find something that will run higher?

[yellowbull20]

You need to make sure that it still has the blow out ring on the lower unit. Also if it's got alot of steering torque it could be crabbing. I had the same problem in my old Bullet. I put another gearcase on and at about 85 mph it would blow out every time. Someone had filled in the blowout ring with bondo so I took a file and worked the bondo down to where the ring was back again . Also reshaped the skeg to take some of the steering torque away. Next time out you could drive it at 93 mph with no problems. Hope this helps.
Cya, Dion

[GE Blazer]

Sounds like that it what it is. I had a Bob's lower unit on mine w/o a torque tab and it would blow out and crab. I sent the lower unit to titus and he put one of his on it and fixed the problem.

[BEEZER]

OK I'll look at his. I see what your talking about on this ring at the back of the gearcasing. GE did Titus's torque tab slow you down any. I've heard some say they slowed and others say they gained speed. I'm still running a streight skeg on mine with cables and can't decided to change it. I know I'm crabbing cause the paint eventually wears little specks off on the port side over a couple months time.

[GE Blazer]

Mine got faster. The boat would only run 87 every time before it blew out. All bassboats running that fast have to have some type of torque tab.