Engine won't turn over.. Seized drive?

[greg82255]

Hello,

I have a friend who just bought a boat with a 1989 OMC 3.0L and Cobra drive. I've only used Mercs so I don't know much about these things, so I'm going to do my best to describe what happened.

He said he changed the gear oil in the drive before he took it out to drive around for the first time. He said that there are 3 plugs on the drive and once he drained the old lube, he removed the lower plug and middle plug and pumped from the lower and waited until gear lube came out of the middle. He didn't do anything with the top screw. Took the boat out, engine ran great for a few minutes, until it died. Once it stopped, it wouldn't start again.

He brought it back to the dock and I looked at it. The battery is good, all connections are tight, and when you turn the key, the starter clicks and engages, and the engine turns about 10 degrees and stops. Once you let go of the key it rotates backwards that same 10 degrees. It's like the engine is trying to turn over and something is stopping it. The drive also turns slightly left every time he tries to crank it over. I was thinking he may have destroyed the upper gears from lack of oil and now the drive is seized. Then again, I'm no OMC expert. Any thoughts on what may have happened?

 

[Idlespeedonly]

Re: Engine won't turn over.. Seized drive?

He probably ruined the upper if he stopped filling when oil came out the middle.

 

[greg82255]

Re: Engine won't turn over.. Seized drive?

He probably ruined the upper if he stopped filling when oil came out the middle.

That was my initial reaction. Is there an easy to check without pulling the drive? If I pulled those 5 bolts out of the cap on top of the drive and removed the cap, would it be obvious if the upper gears gone?

 

[Idlespeedonly]

Re: Engine won't turn over.. Seized drive?

Take the four bolts that hold the cover with the dipstick. And have a look in there. If the gears are bad, it will be obvious.

 

[Don S]

Re: Engine won't turn over.. Seized drive?

It takes 10 minutes to pull the drive. Disconnect the trim cylinders from the drive, and remove the 6 mounting nuts. Pull drive off.
Job over. With no oil in the upper, it's coming off anyway.

 

[Reinell-BRXL-191]

Re: Engine won't turn over.. Seized drive?

Yeah, if he stopped filling once it reached the middle plug, it's all done... as soon as you get the lid off, there will be a ground up mess in the upper - oil needs to be all the way up to the dipstick...

 

[greg82255]

Re: Engine won't turn over.. Seized drive?

Alright, fair enough. Thanks guys. Unfortunately I'm having my own engine problems at the moment so I'll have to just give him a call and tell him to pull the drive and look at the top cap. I assume OMC Cobra drives are not easy to find used..

 

[Idlespeedonly]

Re: Engine won't turn over.. Seized drive?

They are not impossible to find, It is the price when you do find one.

 

[forgot]

Re: Engine won't turn over.. Seized drive?

hmm, just began perusing and stumbled across ya, the motor isn't seized, as it has some movement in it...Trimmed down i assume,... and in neutral for sure... to alleviate any extra resistance, n possibly pinpointing the problem...N he had it out in the water for awhile until it got got good n warm...could be the drive, but before I started pulling the drive, I'd pop out a couple plugs n see if I had water in the cylinders. Was in a merc once when the upper went out, screamed like a hell banshee. Not saying your drive is good, likely not if it wasnt filled properly, but start simple first. Hydrolock is what your symptoms say without the knowledge of the lube job, n knowledge of the lube job is second hand, in my opinion of course.

 

[HT32BSX115]

Re: Engine won't turn over.. Seized drive?

He said that there are 3 plugs on the drive and once he drained the old lube, he removed the lower plug and middle plug and pumped from the lower and waited until gear lube came out of the middle. He didn't do anything with the top screw.

One of the most common ways to kill a Cobra.......

That pretty much sums it up. The drive is "toast"

 

[HCMQA]

Re: Engine won't turn over.. Seized drive?

It IS the drive and you are going to trash the coupler next if you keep trying to start it.
It takes 5 minutes to pull the drive off and/or look in the top cap.

Not sure why so many people don't understand that all these drives turn when the engine turns regardless of if it is in neutral or not.

Fixing/replacing that drive is still very easy and really just depends on how much money you want to spend. Parts are still available.