#2 cylinder went

[drem312]

Well it seems I have done it now, 1996 200hp oceanpro vro connected...I had my fuel pump go last month so I put a new one on and rebulit all the carbs,I took all the carbs off and took them apart can of carb cleaner for each one did not use compress air and really didnt readjust the floats they looked close enough,,went on the lake idle perfect now with new pumps idle screws all around 5 1/4 turns out took off got up to plane and then it just lost power shook and died... got it started crawled home compression test 90on all but #2 40psi removed head and could see above the exhuast port melted aluminum i think ...also the # 4 and #6 plugs looked like they were running hot ..so where do i start?? i assuming that the carb i didnt blow ait threw or adjusted the float caused the problem right? i had fuel up to the carb (pumped bulb gas come out of line to the carb) so i assuming its thgis carb,,,now i had advanced my timing to get the idle a little up (friend suggested this) I read that doing this can burn up some things...please any help would be greatly appreciated

 

[Dhadley]

Re: #2 cylinder went

Tell us how you adjusted the idle timing. Idle timing will have no effect on top end timing.

 

[DJ]

Re: #2 cylinder went

The oil injection CANNOT discriminate which cylinder gets oiland which cannot.

I suspect the damage had started before you went into the carbs.

ou have to rebuild the carbs all the way.

 

[drem312]

Re: #2 cylinder went

i know it doesnt discriminate but if the carb leans out then that cylinder can fry which i suspect the carb screw up i have 6 carbs one for each cylinder...he just turned the screw that moves the timer base(?forward) which brought the idle up then adjusted so that the throttle plates moved as soon as the others moved

 

[emdsapmgr]

Re: #2 cylinder went

It would be very unusual for high idle timing to cause a powerhead meltdown. Usually it is as a result of high high speed timing. Did you bleed the oil system after replacing the VRO pump?

 

[drem312]

Re: #2 cylinder went

i did not bleed the oil sysytem the gas did look like it had oil in it, the primer bulb from the oil tank was hard and the low oil alarm did not go off although i have not check to see even if the alarms work,,,high speed timing can you explain that a little more please??

 

[drem312]

Re: #2 cylinder went

so what do you think????

 

[Dhadley]

Re: #2 cylinder went

Increasing the idle rpm (advancing the timer base) will not affect the top end timing. The only way to advance the top end timing is if you move the timer base stop screw. It's a screw with a rubber cap on it the the timer base hits when at full advance. As long as you didn't move that, and the cap is still on, the top end timing remains the same.

As for why #2 went, you'll have to look a bit further. Just from your discription I'd guess that there was a lean condition.

When looking at the carbs remember that the front half is an "X" design. The carb body in front of #2 feeds #1. IE -- the top port carb feeds the top starboard cylinder. And so on.

When cleaning the carbs you need to clean the throttle body too. Also make sure you use the right carb to throttle body O ring and that it's seated perfectly.

What spark plugs are you using?

 

[drem312]

Re: #2 cylinder went

ahhh that could of been moved,,, I will have to look tonight but a few things were turned to get the rpm up..I had it on the ocean twice and it seemed to run ok after all the adjustments then the OMS went and i replaced that and did a carb rebuild I had a timing light and to me it didnt seem to reach the pointer)timing mark
I do know abot the cross factor and Im using Ql78YC? I have to look again but i think thats whats in there,,the marine had put the 82 plugs in there, I read that these were the right ones

 

[Dhadley]

Re: #2 cylinder went

That spark plug is fine.