Volvo Penta - What do these symptoms indicate?

KNanthrup

Recruit
Joined
Feb 7, 2009
Messages
4
Hi guys, I have an '84 Bayliner Capri 19.5 with the Volvo AQ125A and Penta 270 combo.

I just got the boat and basically it was running and functioning great for the previous owner (a friend of mine), then it was winterized and fogged then it sat for several years (refogged each year).

Now, I'm trying to breathe some life back into it. I replaced the fluids, flushed the gas tank and replaced with new gas, cleaned the spark plugs, cleaned all the ignition terminals, and rebuilt the carburetor.

The symptoms that I'm getting when I try to start it are:
Mostly no response when cranking it over in idle. If I use the primer squirter by pumping the throttle it will sometimes pop and sputter, but not in a good way. Sometimes it will backfire, sometimes it will fire up through the intake, and sometimes it will fire the motor over in promising fashion. If I crank it over with about 30% throttle, starts to smoke and pop up out of the carb and air filter, It will literally "puff" smoke out.

When I took the carb off, I looked inside the intake manifold and gas was pooling up inside and just sitting stagnant.

The plugs seem to be getting fuel because they're wet. I know the plugs are firing too, because I checked them for spark and there is reaction in the motor.

I have been blaming the carb, but it was doing the same before and so I rebuilt it and it's still doing it. I also switched out the inlet float needle valve for it thinking that maybe it wasn't shutting off the fuel. Float isn't sticking either.

I really cannot figure out what the issue is. I'm starting to think that it must be a valve or two that isn't seating. If gas is pooling up inside the intake then it sounds like it's not getting sucked in, plus it's firing up through the carb but the timing is correct. Could this be caused just from sitting for years?

I guess my next step is that I need to do a compression check, and that should tell the story. What kind of PSI should I be looking for?

Any other ideas on what these symptoms point to?


Thanks!
 

Robj

Lieutenant
Joined
Mar 22, 2007
Messages
1,441
Re: Volvo Penta - What do these symptoms indicate?

If you have spark and the carb has been rebuilt, and assuming there is adequate compression to fire, then the most likely cause is that the spark is not happening at the right time. Check your timing belt to make sure it has not jumped a few teeth. I have a 2.3 litre Volvo and this is a common problem with these engines, especially when they are neglected.

Good luck

Rob
 

KNanthrup

Recruit
Joined
Feb 7, 2009
Messages
4
Re: Volvo Penta - What do these symptoms indicate?

Thanks Rob, I'll check that out and do the compression test
 

beaujones

Recruit
Joined
Mar 8, 2009
Messages
2
Re: Volvo Penta - What do these symptoms indicate?

i was curious to find out what you found/
 
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