Volvo Penta 120 stall in gear

[randolf]

I'll preface by stating I AM A GREEN-HORN, I am on my second boat, (I bought the first one 2 weeks ago and it wasn't big or fast enough).

I spent $1800 on a 1980 Campion with a Volvo / Penta 120 I/B, the oil smelled like gas (badly), I changed it, checked the plugs, dist., wires, and decided to take the wife and little guys out for a little trip to see how it ran in the best Salmon fishing area in the world!!!

#1 forgot bilge pump (for the last time), and had a ton of water around the motor.
#2 the battery was low to start with, I used the bilge pump to drain, once it was gone I could barely start it, got a boost, and it ran then stopped. Boosted again, with some throttle, had it sputtering but idleing alone, put it in gear, made it out of the marina thouroughly embarrased, and gave it some gas, it stalls. Waited a minute, started it, get moving and it stalls.

My problem, is under any load, it wont run. The carb had a little water sucked in, the dist. was very slightly damp from the bilge f*#k -up, It seemed to idle at home with muffs okay, I was told possibly the fuel pump, bad diapraghm filling the cyl. with gas, that would explain the gas in oil, possibly the stalling, yes????

Looks to me like the folks who sold it knew thier was a problem, tried replacing the plugs, new cap and rotor, and coil.

Anyone who can help, thanks, I will start troubleshooting, just want to know any ideas on where to start.

 

[Don S]

Re: Volvo Penta 120 stall in gear

Moving to the Mercruiser, Volvo and OMC I/O or Inboard Engine Problems forum.

 

[Don S]

Re: Volvo Penta 120 stall in gear

With lots of gas in the oil, I would guess the fuel pump is leaking.
From there, how about the points and condenser, did you change them?
Did you check the dwell, check the timing, check the fuel filters?
If you have water in the carbs, they won't run very well.
If you are low on power it won't run, get the battery charged up and fix the alternator.
You have a lot of things going on at the same time, get them all fixed and it will probably work.

 

[jamyers]

Re: Volvo Penta 120 stall in gear

Yup, looks like you need to start with a *good* basic tune-up...

Do you have any experience with non-marine engines? I ask because even though it's in a boat, an internal-combustion engine is an internal-combustion engine, so don't let it intimidate you - especially the 120-hp 4-cylinders.

Do you have a manual or something that shows the basic tune-up specs?

Step-by-step:
1. Ignition
Get that battery charged up.

Make SURE your ignition is dead on: DRY, points set properly, dist cap and rotor clean and not cracked, centrifugal advance is operating freely (not junked up and stuck), and that the initial timing is set properly. You'll need a screwdriver, a timing light, and maybe some wrenches.
** Do the ignition FIRST. Most problems start here, but can masquerade as something else (fuel, air, mechanical).

2. Valves.
You've got hydraulic valve lifters, so mis-adjusted valves shouldn't be an issue, but you'll want to eliminate the possiblilty of a burned / leaking valve. Use a vacuum gauge hooked to somewhere on the intake manifold (or carb below the throttle plates), you want a nice steady vacuum reading that's hopefully above 15" or so.

3. Fuel.
Check that fuel pump, sounds like it's leaking gas into the crankcase / oil. Replacement pumps are going to be expensive at your local marine-parts store, but you can get good deals (under $50) on ebay (I just scored one for $35 shipping included). I wouldn't *think* a bad (weak) fuel pump would cause stalling just off idle because there should be enough fuel in the carb bowl. Usually weak pumps cause loss of power at higher rpms as the carb starves for gas.

I'd replace the fuel filter, just because they're cheap and then you'll know it's good.

Carb. It's hard to beat the Rochester 2-bbl (which I assume you have). You've got to open it up and get EVERY BIT that water out of it, period. Take your time and lay all the parts out as you go, so you'll know how to put it all back together. There really aren't that many parts in there, but each one is important. If you really want to assure that the carb is dead on (which I recommend), you can usually pick up a carb rebuild kit (new gaskets and other small internal parts) at a decent auto-parts place for under $20, and just follow the instructions one at a time. Not all that hard to do, really.
The goal is to get the carb CLEAN and DRY.

+++++++++++++++++++++++

The above ought to get you a long way toward having it running like a top, let us know if you have any more questions.

 

[1VolvoPenta2255]

Re: Volvo Penta 120 stall in gear

I have a very similar issue. I am running a 200Hp Volvo Penta 305 with a 275 Penta OB.

My Issue is I can get on a plane, 25 - 30 seconds out from an idle and the motor drops off on its *****. Stumbles, sometimes cuts out. I have to restart it, seems like it is starving for fuel.

If I am at an idle, and I can throttle up, and have great response, I can idle for hours on end, but as soon as I put it in drive, and throttle up, 25 - 30 seconds later it start to stumble.

Ideas

Thanks

1volvoapenta2255

 

[Don S]

Re: Volvo Penta 120 stall in gear

Welcome to iboats, Best to start a new thread with your question, it's not a good idea to stick your question on someone elses thread, even if it is a similar problem even if it's an old thread.