Engine dies after 30 minutes of running fine?

[CHARGER 151]

I have a 1970 Volvo Penta AQ120. It's a 4cyl 120hp engine. On two consecutive weekends I have taken it out and ran it for 30 minutes to an hour without any problems. I then shut it off while anchoring for an hour of so. When I go to run it again the engine starts fine and then shortly there after dies. <br /><br />After it dies it will not start. I'll wait five minutes or so and then try to start it again. Mostly, it will crank, but will not start. If it does start it dies as soon as I give it throttle. I just put in a brand new starter and silenoid. The battery is also new. <br /><br />As I said, this has happened two weekends in a row. I'm confused as to why after having problems the first time it ran fine for 30 minutes the following weekend? Any help would greatly be appreciated!

 

[kev_79]

Re: Engine dies after 30 minutes of running fine?

I am not particularly fimiliar with that engine, but do you know what kind of ignition it has, points, electronic. On vehicles, sometimes the control module next to the distributor gets hot, and will cause the engine to not fire. Sounds to me definately like an electrical prob, but possibly an intermitten carb prob. Any more info you can give may help. Good luck.

 

[CHARGER 151]

Re: Engine dies after 30 minutes of running fine?

Kev,<br /><br />I honestly don't know the specs as far as the ignition goes. I can tell you that it has a Bosch distributer if that helps? The carbs were supposedly rebuilt by the previous owner (a boat repair shop owner) the day I bought it. Tonight I'm going to pull the plugs and have a look, as I have never looked to see the condition they're in. <br /><br />The first time I had this problem the engine would start each time I tried after it had previously died, although I had to beat on the starter with a screw driver first. Then it would run fine up to 1000 rpms. As soon as I increased the throttle it would die.<br /><br />Therefore, I figured I had two problems, a bad starter and a fuel line problem. Before going out this weekend I replaced the starter and poured a fuel system cleaner in the gas tank. <br /><br />When I was out this weekend the same problem occured as the last time except this time the engine would restart after it died. It would try and turn over, but wouldn't start. I kept on trying and then the engine wouldn't even turn over. I t would just make a clicking sound. I would wait 5 minutes or so and then it would try and turn over, but not enough to start. Then it would make the clicking sound again.<br /><br />I hope this helps?