1990dtgl98
Seaman
- Joined
- Jul 17, 2011
- Messages
- 57
Good evening all,
23' bowrider with a 7.4 (L29) engine and bravo 3 drive. Bought and been fixing this past winter, finally got it running we'll enough to use. Been having issues with only getting 3400rpm and 34mph out of it. My biggest gripe though.... pulling skiers up. It just doesn't have the hole shot I feel a 7.4 and dual prop should have, and even my expereinced skiing wife has some trouble getting up. My big body...forget it!
I replaced the fuel pump, regulator, coil, cap, rotor, plugs, iac valve. Have 40psi at the rails. Idles good. Has a slight shake in the 1400-2000rpm range (though goes away so need to check alignment this winter). Thought it might be good to do a drop test and see if I'm only running on 7 cylinders causing this lack of "grunt".
So did a drop test at idle going the old fashioned pop a plug wire off. All 8 I was able to get spark jump so cap/rotor/coil good. However even checking with the rinda, every cylinder only had a 20rpm drop with the drop test. Not one cylinder gave that telltale stutter/stumble that I'm used to hearing with cars.
Any ideas why every cylinder almost acts "dead"?
Should I test at a higher non-load rpm perhaps?
Its going to be hard to test under load and have someone drive the boat and have me in the engine compartment...but if it needs to be done...
23' bowrider with a 7.4 (L29) engine and bravo 3 drive. Bought and been fixing this past winter, finally got it running we'll enough to use. Been having issues with only getting 3400rpm and 34mph out of it. My biggest gripe though.... pulling skiers up. It just doesn't have the hole shot I feel a 7.4 and dual prop should have, and even my expereinced skiing wife has some trouble getting up. My big body...forget it!
I replaced the fuel pump, regulator, coil, cap, rotor, plugs, iac valve. Have 40psi at the rails. Idles good. Has a slight shake in the 1400-2000rpm range (though goes away so need to check alignment this winter). Thought it might be good to do a drop test and see if I'm only running on 7 cylinders causing this lack of "grunt".
So did a drop test at idle going the old fashioned pop a plug wire off. All 8 I was able to get spark jump so cap/rotor/coil good. However even checking with the rinda, every cylinder only had a 20rpm drop with the drop test. Not one cylinder gave that telltale stutter/stumble that I'm used to hearing with cars.
Any ideas why every cylinder almost acts "dead"?
Should I test at a higher non-load rpm perhaps?
Its going to be hard to test under load and have someone drive the boat and have me in the engine compartment...but if it needs to be done...
