Hit rock runs rough now

[jeff6898]

1979 Evinrude 85hp 85999R


Took out the boat today as I was idleing away from the ramp the prop hit a rock. Motor quit. It will re-crank with the fast idle lever up. It now runs real rough. Has a huge miss in it. Will not run at all now at idle or in gear it just misses and cuts off.

Also yesterday it ran perfect at idle but had a miss at ful throttle. NOthing like now. It still ran good with the little miss then.

Has new coils, power packs, fuel pump, carbs rebuilt, wires and plugs.

 

[woody66912]

Re: Hit rock runs rough now

it's very possible you sheared the flywheel key.

 

[tashasdaddy]

Re: Hit rock runs rough now

could have bent a prop shaft, binding, remove plugs and turn flywheel by hand.

if you hit it hard enough to stop the motor, you could have sheared the flywheel key, throwing the motor out of time. would require, pulling flywheel, and a new OEM ( not hardware store) woodruff key. then properly torquing the flywheel.

requires harmonic balancer puller, grade 8 hardened bolts to fit your flywheel,

 

[jeff6898]

Re: Hit rock runs rough now

Ok I removed the plugs and could easily turn the flywheel by hand. The pistons move up and down just fine when I do. Should I have been able to turn the flywheel so easily?

 

[Xcusme]

Re: Hit rock runs rough now

Yes, it should turn freely. Your next move is to remove the flywheel, as was previously suggested, to check the flywheel key, it may be partially sheared.

 

[tashasdaddy]

Re: Hit rock runs rough now

that is my guess, it stop so quick, the weight of the flywheel broke the key.

 

[jeff6898]

Re: Hit rock runs rough now

Any idea where I can buy a puller from? No one locally I called sells them. I checked compression for the heck of it. 135 all 4. CHecked spark. excellant .

 

[jeff6898]

Re: Hit rock runs rough now

ANyone know where the flywheel key would be? I am looking at the parts diagram and my service manual and do not see it listed.

 

[tx1961whaler]

Re: Hit rock runs rough now

An auto parts store sells a "harmonic balancer puller that works just fine...
I got one at AutoZone 14.99

 

[mikesea]

Re: Hit rock runs rough now

the key is a half moon shaped projection located in a slot on the crankshaft area covered by the flywheel,it is what stops the flywheel from rotating on the driveshaft

 

[tashasdaddy]

Re: Hit rock runs rough now

when you look down at the flywheel there is a slot in the flywheel and the crankshaft, the key is in there. you have to remove the nut.

 

[HighTrim]

Re: Hit rock runs rough now

After you get the harmonic balancer puller, be sure to upgrade the bolts like stated to Grade 8. Screw them in 7/16 of an inch. When re installing, be sure that the taper is clean and dry, then torque to spec.

 

[jay_merrill]

Re: Hit rock runs rough now

OMC/BRP also sells a puller with a variety of bolts for use on a variety of flywheels and gearcases. They are a little pricey (I paid about $65.00 for mine about 7 years ago), but they get the job done, and there is no fooling around trying to make sure that you have the right bolts.