arriva2450
Cadet
- Joined
- Jul 31, 2012
- Messages
- 11
Really would appreciate some advice on my 4.3GL carbed engine. It has been giving me an issue all summer, where it fires up great, idles great and runs great on WOT for only the first 5 minutes - at that time is starts to bog and sputter and sounds like it wants to stall unless I let off the throttle at which time it backfires once or twice and then goes back to WOT for another few minutes until it does it again, and again, etc.
I replaced the fuel pump and fuel pump relay which made no difference. I checked compression and all perfect. While plugs out (which are NGK bpr6efs, gapped at .045) I did see they showed signs of lean so I richened the carb (which is a Holley 3250R 2 barrel) - this made no difference.
So not knowing how old the plugs were (I bought the boat 2 years ago), I replaced the plugs with AC Delco MR43LTS - fired up and idled good so I took for a spin but immediately it wouldn't even go to WOT - when giving throttle it would just backfire (only idled good) and then stalled. Tried to start it up again and nothing - towed it back to my dock and put in the original plugs again thinking the boat just didn't like the new plugs. Unfortunately the old plugs now made no difference - it is cranking but not even a pop - nothing. I re-checked compression and all good. I used a spark tester on each cable and all have spark. I am now lost as to why it isn't starting????
Would really appreciate some advice on the no start, and then some advice of the original problem I was having, as I still need to figure that out once I get this thing running again.
Oh, I also did check timing, but doubt that is the reason for the no start (might be related to the original problem though). I read that this motor wants 1 degree BTDC initial, and confirmed that was set right.
Thanks
I replaced the fuel pump and fuel pump relay which made no difference. I checked compression and all perfect. While plugs out (which are NGK bpr6efs, gapped at .045) I did see they showed signs of lean so I richened the carb (which is a Holley 3250R 2 barrel) - this made no difference.
So not knowing how old the plugs were (I bought the boat 2 years ago), I replaced the plugs with AC Delco MR43LTS - fired up and idled good so I took for a spin but immediately it wouldn't even go to WOT - when giving throttle it would just backfire (only idled good) and then stalled. Tried to start it up again and nothing - towed it back to my dock and put in the original plugs again thinking the boat just didn't like the new plugs. Unfortunately the old plugs now made no difference - it is cranking but not even a pop - nothing. I re-checked compression and all good. I used a spark tester on each cable and all have spark. I am now lost as to why it isn't starting????
Would really appreciate some advice on the no start, and then some advice of the original problem I was having, as I still need to figure that out once I get this thing running again.
Oh, I also did check timing, but doubt that is the reason for the no start (might be related to the original problem though). I read that this motor wants 1 degree BTDC initial, and confirmed that was set right.
Thanks
