Mr. TryToFixIt
Recruit
- Joined
- Sep 27, 2021
- Messages
- 1
Hi All,
Been trying to figure this one out for some time, and about maxed out my current capabilities.
I have twin Volvo Penta 7.4 Gi's, one with a no-start condition.
I'm getting spark, I'm getting gas, I'm getting compression, but she won't start.
For spark I replaced the plugs and used a spark tester, visual inspection. Also tried alternating coils in case I was getting weak spark. Spark is white.
For gas, pulled the plugs and they come out wet/gasy, smells like gas when cranking.
For compression, highest 140 and lowest 128 which seems within spec for the engine.
Context of issue: Both engines have been kinda screwy, showing the same/similar symptoms. Including no cold-start at times, no warm-start at times, turning off while idling, and I had one engine max out at 2500 RPM's on the way back once, which the manual says is a safety control due to a bad sensor/ECM. I also swapped the ECM's which didn't work either.
If I half know what I'm talking about the problem is narrowed down to timing, a bad sensor, or like bad gas in the tank with water? I also tried spraying some ignition fluid in the intake to see if I could get it at least started with a little help, no good.
If you have any other ideas please let me know, I have a mechanic coming tomorrow but I know he doesn't have a code reader for this so hoping it's not a total waste of time and money.
Thanks all.
Been trying to figure this one out for some time, and about maxed out my current capabilities.
I have twin Volvo Penta 7.4 Gi's, one with a no-start condition.
I'm getting spark, I'm getting gas, I'm getting compression, but she won't start.
For spark I replaced the plugs and used a spark tester, visual inspection. Also tried alternating coils in case I was getting weak spark. Spark is white.
For gas, pulled the plugs and they come out wet/gasy, smells like gas when cranking.
For compression, highest 140 and lowest 128 which seems within spec for the engine.
Context of issue: Both engines have been kinda screwy, showing the same/similar symptoms. Including no cold-start at times, no warm-start at times, turning off while idling, and I had one engine max out at 2500 RPM's on the way back once, which the manual says is a safety control due to a bad sensor/ECM. I also swapped the ECM's which didn't work either.
If I half know what I'm talking about the problem is narrowed down to timing, a bad sensor, or like bad gas in the tank with water? I also tried spraying some ignition fluid in the intake to see if I could get it at least started with a little help, no good.
If you have any other ideas please let me know, I have a mechanic coming tomorrow but I know he doesn't have a code reader for this so hoping it's not a total waste of time and money.
Thanks all.
