Please help, Running problems 1993 Volvo Penta V6 434a, 4bbl holley, help.....

[win-or-bin]

Hi all,
Really need some help with my running problems with my 1993 penta 4.3 v6 with a 4BBL holley. 2 years ago while out with my wife towards the end of the season my engine started running rough, it would throttle up and run on the hose fine but under load it would totally die, drop off the plane and I could just catch it before it died by working the throttle and get going again only for this to repeat itself, not ideal in the ocean!! I put the boat away for winter as we had just had a baby figuring it was an easy fix Carb rebuilt or distributor cap problems. Last year I ordered a genuine holley rebuild kit and rebuilt the carb but didn't manage to get anything else done due to a one year old taking up all my time! This year I have promised my daughter a ride in the boat so I have replaced.......carb back on boat, HT leads, new Distributor cap, New rotor, new Fuel water filter, drained fuel tank, all new fuel, new plugs and oil etc in engine. Tonight was the big launch night, daughter and wife watching from shore and guess what.....Exactly the same as it was!!! Runs/ticks over on the hose but out on the water doesn't feel right, throttles up ok but then just dies, get it going again, under load and dies. So with all I have done it has not changed one bit so I guess I can rule some stuff out, I don't have unlimited money to throw at the boat with a young family so would love to hear some ideas from you guys, I was thinking fuel pump or Ignition module next????

Sorry for the over long post but was so sure I would have it going this year

Thanks in advance

 

[Bondo]

Ayuh,.... Welcome Aboard,... I'm thinkin' ya still got a fuel problem,...

Hook up a remote tank of fresh gas to the fuel pump, 'n try it,....
That'll eliminate the tank, 'n lines,...

Next step would be testin' for 4 to 6 psi at the carb,....(fuel pump test)

 

[win-or-bin]

Hey, Thanks for taking the time to help, How would you test the pressure at the carb?

 

[Scott Danforth]

at the top of every sub-forum is a few "sticky" threads with how-to info. http://forums.iboats.com/forum/engi...68-must-have-technical-information-for-diyers

you most likely have a fuel issue if fiddling ith the throttle keeps the motor going, however not going to rule out other issues.

to me it sounds like a bad needle and seat or float setting. when you cleaned the holley, did you just spray carb cleaner or did you let it soak, then get a fine piece of wire and chase the passages prior to spraying carb cleaner?

also, have you checked timing? coil?

 

[win-or-bin]

Hi, thanks do much for the reply, really appreciate it, I am pretty sure the holley is cleaned good, had the whole carb in bits and cleaned in a ultrasonic cleaner. Not thought of the timing, could it go out? Thought once the timing was set that was it? Don't think I have a coil as have an ignition module. Sorry if I am totally off as am a motorbike guy and have grown up with fuel injection etc, this is my first old school engine!!
Thanks again

 

[win-or-bin]

Hi, just an update for the thread, checked the coil as suggested and the low ohm value is falling out with the penta specs, the low side should be 0.35 to 0.45 ohms and I am showing 0.8 to 0.9 ohms. The high side checks out though should be 7500 to 9000k and I am showing 8000k ohms. Have ordered a new coil so will keep the thread updated if this solves the problem.
Thanks