Jana

In the wake of Saturday's TOPPS poker run, my 29 Fountain is headed for the repair shop and I'm curious what all of you guys think the problem (or problems) is (are). It's a '96 HP500 single carb, not EFI.

Ran great for the first 1 1/2 legs. Then we stopped for a no-wake zone. Getting back on plane there a sort of rattling noise that we determined only happened in gear and under load (i.e. not at idle). After leaving the second stop, no more noise, but she was sluggish to plane, my water temp gauge was all over the place and the buzzer was going off. We got on plane and a while later, my electronic compass quit (oh, the depth gauge was screwy going into the second stop also). After about an hour's ride up the bay, we slowed for the inlet and she sounded kind of rough. When we got back in the lake at the other end of the inlet, 2500 rpm was all she'd give.

So, anyone care to give me their expert opinion before my mechanics try to talk me into some really expensive repairs?

Breathe Later

Valve springs are an issue with HP 500's and possible reversion with the stock exhausts. Check out the archives in Powerboat mags Teague on Tech column. Do a comp. check and remove the valve covers and check the spings.

Regards,

Mark S.

Jana

Thanks! Compression check was the first thing my mechanic said he'd do. I am aware of the valve spring issue and with 185 hours on her, that could be it. I was hoping to make it to winter and do them then on prospect.

Breathe Later

Jana,

With a broken valve spring, comp check may still yield good results. Sometimes the broken inner valve springs (they break before the outer ones). can "corkscrew" and hold the valve open too, showing low comp. Hope for the best!!

Good Luck-

Mark S.

Turbojack

If the valve spring is the problem then why the buzzer going off & depth gauge going wacky? Blown head gasket? More that one problem? Water pump for high water temps, & electrical problem (ground) for compass & depth. May be multiple problems? Who you take it to?

Ted G

iTrader: (1)

There may be an electrical problem that is the root of it all. A bad ground circuit could cause all the problems including poor performance. The depth and compass are very susceptible to "dirty" power-as is the ignition module. Be sure to tell whoever looks at it ALL of the strange things that happened-it may lead him/her to a fix quicker.

otis311

Electrical would be my Guess, NOT the valve springs, Due to the other things that went wrong, Valve springs wouldnt do that to your compass and depth finder

Bob

Vinny P

I agree with the electrical. Check there first.

cuda

I'm suspecting electrical also. Check you main grounds to the engine.

candyman35

Electrical. Something must have come lose. Your ignition is not going to work properly at a lower voltage.
Dan