1989 Eliminator open bow
Fresh top to bottom rebuild with a 90 over on 454. 6.7 hrs was cruising at 40 mph sounding really nice. Boat sudden Loss of speed 40 to 28mph no power then sudden "clunk" motor dead. Try to refire, get click-click. Open cover and steam pouring out of breathers and carb. Didn't note oil pressure at time of motor dying but a few minutes before was 60-65 psi. Turned key on noted 130 degrees felt exhaust which was warm, not hot. Trailered checked intake, nothing visual in impeller. Boats at the motor builder. All on beach saying "motor". Builder trying to say pump froze.....thoughts?


89' Eliminator
508BBC Berkley Jet

Sounds like a head gasket if you have steam coming out the carb and breathers

Sent from my SGH-T999 using SoCalJetBoats mobile app

If you can disconnect the pump from the engine and see which one moves freely.

Ok my builder is separating the drive tomorrow. As for oil level, full, clear and no burnt smell. The jet was a blueprint/rebuild last year, a berkley with jet-a-vator.

Thanks for input, I've had a short summer waiting for this motor to be finished and now this!
Keep ya posted!


89' Eliminator
508BBC Berkley Jet

Hope everything works out. This is why I do all of my own work,. Relying on someone else to repair and diagnose is just not in my vocabulary.

Yeah I typically do all my own work (cars and my bikes) but my room is limited and HOA threatens fined if neighbors tattle on my wrenching.

If it turns out to be a jet issue is this something I can tackle in my buddies garage or they a total nightmare? Done a few jet skis, I assume they have some sort of similarities. Hoping for the best but expecting the worst 😁 keep telling myself "look at all the fuel money I'm saving!"



89' Eliminator
508BBC Berkley Jet

Was competed 3 weeks ago, have 7.3 hrs since regaining her. The builder says engine issues are on him the owner of machine/motor build shop (builders dad) race engine do not get warranty. Not a race engine just 710 HP of fun.  So needless to say told owner that's BS I didn't drop 5k (I brought all the goodies) to get 704.224 $$ per hour!


89' Eliminator
508BBC Berkley Jet

Yeah I left my MX bikes in driveway after pressure wash. they left me a hate note and a fine for $85 gotta love them


89' Eliminator
Stroked BBC Berkley Jet

Was competed 3 weeks ago, have 7.3 hrs since regaining her. The builder says engine issues are on him the owner of machine/motor build shop (builders dad) race engine do not get warranty. Not a race engine just 710 HP of fun.  So needless to say told owner that's BS I didn't drop 5k (I brought all the goodies) to get 704.224 $$ per hour!


89' Eliminator
508BBC Berkley Jet

710HP for $5K?...please share the build.

Well update, builder called said separated jet from motor, jet is fine can't turn motor more then a 1/4"
Pulling motor said "I don't build motors that last less then 100's of hours before maintenance" so he and I are on the same page with a "warranty" idea.
My brother mentioned something about this new crank probably wasn't turning freely, probably the reason for failure.  Any input to what he's saying? Again not a mechanic but familiar to a point around the motor.


89' Eliminator
Stroked BBC Berkley Jet

Motor apart. No obvious signs of lack of oil/lube all bearings are nearly perfect. Crank was gorgeous but my cam was in three pieces and #7 piston broke into 5000 pieces
Here are some pics

Some discussion with Comp Cam and Keith Black distributor. They want all the left over valve dimensions, the spring tension(coil?) and few other details KB claims they've never seen their pistons explode quite like that. I've never seen the end of a cam shatter into pieces

What's your guys' thoughts?


89' Eliminator
Stroked BBC Berkley Jet

First, not sure KB makes a .090" over piston.  And, a KB Piston to me indicates its hypereutectic, rather than forged.  It could still be an older KB forged piston, or one of their newer "Icon" brand forged pistons.  I would like to know the part number and dome volume, and what heads you have and combustion chamber size.  This is a pump gasoline engine,, what compression was it supposed to be? 

The broken exhaust valve may have caused the incident, depending on compression, fuel octane, and ignition timing. 

I recently rebuilt an engine that was sold to the guy by a shop as "9.6-1 compression".  He brought it to me with holes in three pistons, and signs of detonation on the rest of the set.  Looking at parts and some calculations showed it was  actually about 11.8 or 11.9-1 compression, way out of line for pump gas with his closed chamber iron heads.  Unfortunately that shop had closed and the owner in a serious medical condition so he had no recourse than to have someone else rebuild it correctly.

The cam was probably broken by pieces of piston bouncing around and jamming it up, and the bottom of the cylinders damaged by the rod thrashing around without a piston to keep it centered in the bore. 

Was competed 3 weeks ago, have 7.3 hrs since regaining her. The builder says engine issues are on him the owner of machine/motor build shop (builders dad) race engine do not get warranty. Not a race engine just 710 HP of fun.  So needless to say told owner that's BS I didn't drop 5k (I brought all the goodies) to get 704.224 $$ per hour!


89' Eliminator
508BBC Berkley Jet

I would like to know more about the exact parts combination,, and where the "710 HP" figure comes from, especially with a flat tappet cam, unless it's a higher compression engine designed to run on better than pump gas.