93 70hp force power and rpm loss

[gsxr11]

3 cylinder single carb,<br />motor was running fine turning 5k at 39mph....<br />did some tight turns at slower speed but at wot<br />boat sort of spunout like a car would do so i <br />cut power quickly. motor started running rough at<br />idle and stalled, after which it took several tries<br />to get going caulse motor would stall when put in gear. after getting it going it would only turn<br />4500rpm at wot... carb butterfly is opening all the way at wot.. any ideas as too what happened???

 

[roscoe]

Re: 93 70hp force power and rpm loss

Check the compression.<br />You may have broke a ring or otherwise damaged the motor if it over-revved during the spinout.

 

[speedwrench]

Re: 93 70hp force power and rpm loss

If compression OK (should be around 125# and even)<br />pull intake manifold and check reeds. Bad reed on one cylinder will cause exact symptoms you have.

 

[gsxr11]

Re: 93 70hp force power and rpm loss

COOL, gonna check comp. tonight then reeds if need<br />be...<br /><br />i talked to the local force dealer and he seems<br />to think its electrical....<br />i'm gonna check the mechanical things first..<br />let ya know what i find tonight...

 

[gsxr11]

Re: 93 70hp force power and rpm loss

ok,<br />i got motor hot did comp. test all three cyl. are<br />at 115psi even....<br />i didn't have time to check the reeds, i did a de-carb the motor runs 4800 at 37mph now.<br /><br />motor ran good from idle too wot, it still acts<br />as if the throttle isn't opening all the way...<br /> <br />so i shut motor off and fished for a hour, when i started it up again the bad idle was back but the motor still ran at 48-4900 but it wasn't crisp<br />on throttle responce like it was...

 

[speedwrench]

Re: 93 70hp force power and rpm loss

Pulling the intake to check reeds is minor job. They will be right there in plain sight. Should be able to use same gasket. Seal with THIN coat of RTV if need to, but DO NOT let any squeeze into the manifold. If you do and the reeds aren't bad, they soon will be.

 

[eurolarva]

Re: 93 70hp force power and rpm loss

after restart with bad idle try pushing the choke button in for a second. Does this smooth out the idle, kill the motor or have no effect? if it smooths out the idle you probably have a gas problem

 

[wakebite]

Re: 93 70hp force power and rpm loss

This may be way out In left field, But I've seen It on a few occassions. Because of your hi speed mess'in around, your fuel pick up In the tank could have picked up some trash or water. I just seemed coincidental that all this happen at one time, but seemed to Improve over time...

 

[roscoe]

Re: 93 70hp force power and rpm loss

If comp and spark are good, time to get into the fuel system. I would start with pulling the carb, look at the reeds, then rebuild the carb.

 

[speedwrench]

Re: 93 70hp force power and rpm loss

WELL???????

 

[gsxr11]

Re: 93 70hp force power and rpm loss

havn't had time to check it yet, i'm gonna try tonight... river is muddy right now so i can't test run yet either... but i will look at the reeds and check fuel lines..

 

[gsxr11]

Re: 93 70hp force power and rpm loss

ok, i pulled the reeds and they look fine..<br />no cracks and they all are laying flat...<br /><br />whats next to check ???

 

[wakebite]

Re: 93 70hp force power and rpm loss

Take a sample of the fuel. Diconnect fuel line at engine and pump a couple pints into a glass jar; look for water or trash....

 

[WhiteHorse]

Re: 93 70hp force power and rpm loss

Fuel delivery may well the problem, but I would open the fuel pump, check to see if the junk is right there first.

 

[96force 75hp]

Re: 93 70hp force power and rpm loss

How to check reeds? Could this be my problem with bad idle and strange tac rise and fall.

 

[gsxr11]

Re: 93 70hp force power and rpm loss

ok no junk in fuel or in the fuel pump,<br />diaphrams are not leaking and the check valves<br />are still in good condition.....<br />fuel filter is new...

 

[eurolarva]

Re: 93 70hp force power and rpm loss

Sounds like it is time to rebuild carbs. Kits are about 14 bucks per carb. Should get the fuel pump rebuild kit and do that as well. It could be electrical but the fuel system is easier to troubleshoot and repair.

 

[vondean]

Have you checked the Switch and the Coils? See if the plugs are soaked, you have no spark

 

[pnwboat]

Hey vondean.....looks like you're responding to a post that is 11 years old.