Figured it out !!!!!boat won't do over 3200 RPM

[vipzach]

The mechanic says everything is right with the motor, timing, spark, gas. It starts up easy, revs great in nutral, under load it won't do any better than 3200 RPM. I have a 14.25R17 SS rapture prop. What else to try?<br />BTW it is a 1991 VIP 17.5' 3.0 with alpha 1 drive.<br />thanks Zach<br /><br />Well it was the wrong gear ratio!!!! He had put in 1:50 not 1:98. Now it gets up and runs 4500 RPM and runs like a champ. Thanks for the replies.

 

[Boomyal]

Re: Figured it out !!!!!boat won't do over 3200 RPM

Have you checked that the carburetor linkage is full open at full throttle? Not a Merc expert but that seems like a pretty stiff prop for that motor. I'm running a 15 x 17, with a 1:1.50 ratio, on a 20 ft 5.0 litre. My WOT gave about 4700 rpm with a whole lot more umph behind it.

 

[tommays]

Re: Figured it out !!!!!boat won't do over 3200 RPM

a healthy 3.0 should have no problem spining that prop<br /><br />i can run a 14 x 19 on a 19 ft with a 3.0 at 4800 that 2 to 1 ratio makes a big difference<br /><br />it has made RPM in the past ?<br /><br />check timeing for full advance and other basic motor things <br /><br />tommays

 

[jeff13601]

Re: Figured it out !!!!!boat won't do over 3200 RPM

I was thinking prop at first but that boat probably came with a 14 x 19. It should turn that 3200 easy. I guess you should do what has been suggested and check the linkage and do a tuneup

 

[vipzach]

Re: Figured it out !!!!!boat won't do over 3200 RPM

It has new plugs, rebuilt carb, mechanic said it is advancing fine. I checked the carb linkage and it opening up all the way. I don't know abot what it has done in the past, I have only owned this boat since Dec. It also has new impellar and gimble bearing and the top half of the drive rebuilt.

 

[tommays]

Re: Figured it out !!!!!boat won't do over 3200 RPM

there is no other way than to start at the most basic thing<br /><br />do your OWN compression test and work from there you dont really no that the motor is healthy unless you do it your self<br /><br />same thing with the timeing you have used a mech and not solved the problem you have to see that it is really working corectly and not thinking that it is<br /><br /><br />tommays

 

[vipzach]

Re: Figured it out !!!!!boat won't do over 3200 RPM

Well it was the wrong gear ratio!!!! He had put in 1:50 not 1:98. Now it gets up and runs 4500 RPM and runs like a champ. Thanks for the replies.

 

[Ralph 123]

Re: Figured it out !!!!!boat won't do over 3200 RPM

I remember a case just like this about a year or so ago...

 

[QC]

Re: Figured it out !!!!!boat won't do over 3200 RPM

Wow! Just goes to show, can't rule out anything. I bet you're relieved.

 

[vipzach]

Re: Figured it out !!!!!boat won't do over 3200 RPM

Very relieved, I finally got to fully enjoy my boat last night. I loved it!<br /> <br />Ralph did the same thing happen to you or just somebody else on here?

 

[Scaaty]

Re: Figured it out !!!!!boat won't do over 3200 RPM

Originally posted by vipzach:<br /> Well it was the wrong gear ratio!!!! He had put in 1:50 not 1:98.

Good Lord, thats the LAST thing I would think of!

 

[Ralph 123]

Re: Figured it out !!!!!boat won't do over 3200 RPM

Somebody else on here. I almost posted the suggestion but figured you knew what you had... sorry. Wish I had posted it. You can still find it using the search function.

 

[Ralph 123]

Re: Figured it out !!!!!boat won't do over 3200 RPM

I found it:<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=24;t=003719#000012

 

[vipzach]

Re: Figured it out !!!!!boat won't do over 3200 RPM

I knew what I was supposed to have, and my mechanic/friend swore up and down that there was no way he could have made that mistake. Finally the other night I made him recount the gears....guess what....he was wrong. It is funny now, but not last weekend when I was at the lake.

 

[KaGee]

Re: Figured it out !!!!!boat won't do over 3200 RPM

Geee boss, I always did want to werk on one of dem dare outdrive thingys.....