Volvo Penta 270 idles great but wont run underload

[wapitiguide]

I have a 1983 Volvo Penta 270. I have replaced the spark plugs, rebuilt the carb, timed the engine. At first it would not even idle. Now it will and sounds pretty good. I can put it in gear and it will putt along. As I increase the throttle it dies. Unknown what to check or do now. Any help would be nice. Thanks in advance.

 

[Don S]

Re: Volvo Penta 270 idles great but wont run underload

The 270 is an outdrive, not an engine. What is the model number of the engine?

 

[wapitiguide]

Re: Volvo Penta 270 idles great but wont run underload

It is the aq125a, 4 cylinder

 

[Don S]

Re: Volvo Penta 270 idles great but wont run underload

For those engine to idle correctly, the point dwell needs to be at 62? or 63? for best results. Then you set the timing at 750 rpm or less.
After setting the timing, adjust the idle mixture for the carb and idle speed to 900 rpm.

 

[wapitiguide]

Re: Volvo Penta 270 idles great but wont run underload

This might be a dumb question, but I'm not sure how to check the dwell. So can you explain. Thanks

 

[Don S]

Re: Volvo Penta 270 idles great but wont run underload

Dwell is the measurement in degrees of how long the points are closed. It's also checked with a dwell meter. You change the dwell by opening and closing the gap of the points until the dwell is in the right spec.
The spec actually says 62? + or- 3?. But the 62? or 63? gives you best running results.

Google dwell and dwell meters for more info.