ericstiffler
Recruit
- Joined
- Aug 8, 2008
- Messages
- 3
Weirdest problem. Its been like this since I bought the boat 2 years ago. Pretty sure the previous owner knew the problem and didn't disclose. Determined to fix it this year. Description:
The motor starts perfectly, idles perfectly, and leaves the harbor perfectly. I punch it to get out on the water and it accelerates great, gets up to plane, runs like a charm. After its been running for a while, I'll slow down to idle, or maybe turn it off all together. A little while later I try to get going again, and the motor starts to rev up, but suddenly bogs down and dies (unless I can back the throttle off quick enough). Try it again, maybe three, four, ten times...nothing..always bogs down (and dies if I persist with the throttle). So I make my way along at a snails pace (slightly above idle). Doesn't matter if I try to ease the throttle forward slowly, it can't be fooled..hits the theshold and bogs. Five minutes later, I try the throttle again, it hesitates like its going to die again, but no...vroom..it shoots out of the hole and I'm off doing 32+mph. (17ft fiberglass Chris Craft BTW). I slow down again, or I stop to fish again..try to get back going..maybe it takes off, may does its stalling thing again. Now: Its a load related problem. It rarely gives me problems with only 2 people in the boat, and if it does, I can usually coax it pretty quick. It ALWAYS does it when I try to pull a skier. I managed to get up a couple of times myself by pulling on the rope to get my butt out of the water at same time driver hit accelerator to get past the problem range. I've taken it to the mechanic last year. He rebuilt carbs, fuel pump, new sparks..all the general maintenance. No improvement. The guy before me had some electronic module replaced (I think related to ignition) at marine shop. I even get impression that this problem may have extended to the owner before him. Also, never seems to have a problem the first time in the day I hit the throttle. Always roars out of the harbor/launch area, even with 4-5 people on board. But I could be anchored out for 2-3 hours fishing, start to head back in, have it bog down and die.
So where do I start diagnosing this? Any ideas? I haven't really done anything myself yet. I tried the mechanic last year, but it seems like they want to throw parts at it until something works and I can't afford that approach. All ideas are appreciated. I have fair mechanical experience on cars, but this is my first go on a marine motor.
'83 Inline 6, Mercury OB, 115Hp
The motor starts perfectly, idles perfectly, and leaves the harbor perfectly. I punch it to get out on the water and it accelerates great, gets up to plane, runs like a charm. After its been running for a while, I'll slow down to idle, or maybe turn it off all together. A little while later I try to get going again, and the motor starts to rev up, but suddenly bogs down and dies (unless I can back the throttle off quick enough). Try it again, maybe three, four, ten times...nothing..always bogs down (and dies if I persist with the throttle). So I make my way along at a snails pace (slightly above idle). Doesn't matter if I try to ease the throttle forward slowly, it can't be fooled..hits the theshold and bogs. Five minutes later, I try the throttle again, it hesitates like its going to die again, but no...vroom..it shoots out of the hole and I'm off doing 32+mph. (17ft fiberglass Chris Craft BTW). I slow down again, or I stop to fish again..try to get back going..maybe it takes off, may does its stalling thing again. Now: Its a load related problem. It rarely gives me problems with only 2 people in the boat, and if it does, I can usually coax it pretty quick. It ALWAYS does it when I try to pull a skier. I managed to get up a couple of times myself by pulling on the rope to get my butt out of the water at same time driver hit accelerator to get past the problem range. I've taken it to the mechanic last year. He rebuilt carbs, fuel pump, new sparks..all the general maintenance. No improvement. The guy before me had some electronic module replaced (I think related to ignition) at marine shop. I even get impression that this problem may have extended to the owner before him. Also, never seems to have a problem the first time in the day I hit the throttle. Always roars out of the harbor/launch area, even with 4-5 people on board. But I could be anchored out for 2-3 hours fishing, start to head back in, have it bog down and die.
So where do I start diagnosing this? Any ideas? I haven't really done anything myself yet. I tried the mechanic last year, but it seems like they want to throw parts at it until something works and I can't afford that approach. All ideas are appreciated. I have fair mechanical experience on cars, but this is my first go on a marine motor.
'83 Inline 6, Mercury OB, 115Hp