6.2 no power, dies at idle

brandonmayberry

2002 Rinker 342 FV. has twin 6.2 engines. around 700 hours. Replaced my port engine last season. Now my Starboard is acting up. Started out where it was running fine and would start fine but sometimes after warming up it would die when i would lower the rpms to either idle gear or neutral. Engine would sometimes start back and keep running or sometimes in would die a few times until i throttle up and get the RPMS up and them come back to idle and it would be fine.

Then it began to lose power. Started barely wanting to get on plane and wouldnt get over 3000pms, now it wont get on plane at all and wont get over 2200 RPMS.

Ive ran a fuel pressure gauge on it and fuel pressure acts perfect both under load and at idle. Ive replaced the IAC. Ive replaced the fuel water seperator.

It has new plugs, wires, cap and rotor as of late last season.

It does sound to have a real random misfire however when at idle. you can hear a thunk sound every 2 to 3 seconds but it doesnt appear to be consistent.

Ive ran the Rinda Diacom on it and it shows no codes, guardian mode, or power loss. Everything parameter wise reads the same as the port engine.

Any ideas? TIA

earl1z19

Have you check the quality of the fuel source for that motor?

brandonmayberry

It’s same ya the other engine runs in which is doing fine and the tanks plum together. 

GMSLITHO

what about the water separator or fuel filter 

F1100

A thunk noise... like a misfire thunk..or a mechanical thunk?

Cableguy Greg

What about the IAC valve?

brandonmayberry

I changed fuel water separator and IAC already 

randy56

compression check?

brandonmayberry

randy56 said:

compression check?

That’s the next step. 

Black_Diamond

Maybe like the issue with the longest thread ever: the exhaust water problem. 

brandonmayberry

Ended up being a spark issue. Changed cap and rotor and it fixed the loss of power issue. However the engine still intermittently dies a low idle or neutral. Outdrive has a knock sound also. I’m think maybe shift needs adjusted? Any idea on that? 

brandonmayberry

Been a long time but going back through my threads. Ive had continual cap and rotor issues on this boat. They need changed about once a year due to corrosion for some reason.

The solution to dieing when at low idle or neutral after having been ran turned out to be a fuel pump issue. The low pressure side was bad i guess.

The outdrive was an issue wiht the gear set in the upper. Had to replace those, Unfortunately its starting to do it again. Hoping the new shift cable i installed has just stretched some as its very intermitten.

Didnt want to leave a thread unanswered. Hope someone else can learn from my mistakes.

Pat310

Nice update   Sure it will help someone now or in the future