OMC Cobra Trim Cylinder Length

[TRobin9496]

Does anyone know what the fully extended length of a Cobra trim cylinder should be? Preferable dimension from one mounting hole to the other. I'm trying to determine if mine are extending fully. Thanks.

 

[Bondo]

Re: OMC Cobra Trim Cylinder Length

Ayuh,... Disconnect the outer most end,+ run it out...

 

[TRobin9496]

Re: OMC Cobra Trim Cylinder Length

Thanks for the response.

I already did what you suggested. Just doesn't look like it's out all the way. I may just take it apart to see if something could be stopping it from extending all the way. I can't seem to find the extended length info anywhere on the internet.

FYI. I converted from Cobra to SEI using their kit and the new drive doesn't lift up high enough to trailer because the new unit trim mounting holes are further back on the drive. Just wanted to make sure the real problem isn't my cylinders before I call SEI...I think I'm going to call anyway right now.

 

[Lou C]

Re: OMC Cobra Trim Cylinder Length

Does anyone know what the fully extended length of a Cobra trim cylinder should be? Preferable dimension from one mounting hole to the other. I'm trying to determine if mine are extending fully. Thanks.

measured mine today (1988 Cobra) 23" from the center of the mount on the drive to the mount on the transom...

 

[TRobin9496]

Re: OMC Cobra Trim Cylinder Length

Thanks for measuring. I talked to a guy at SEI today and he also measured one that they had at 23". I thought mine looked a little short at 20 1/4".

After I found out that they were short, I was expecting to find something bent or broken inside. After pulling the ram and piston assembly I quickly saw hte problem. There was a 2 3/4 plastic tube fitted around the ram which was limiting the travel to 20 1/4". I just removed the tubes, and everything works fine now...and for no $$$ spent. It was a good day.

I still can't figure out why the limiters were put in there. The only slightly feasible reason I can think of would be to prevent drive from being trimmed up too high while running. The prop of the original Cobra drive did tilt up higher due to the trim cylinder mounting holes being further forward, and the prop housing being longer, so maybe the boat was set up that way when it was new.

 

[Lou C]

Re: OMC Cobra Trim Cylinder Length

Glad it was a simple solution...btw how do you like the SEI conversion? I might consider doing this when my Cobra needs replacing...so for so good but you never know...22 years and counting! How well does combining the shift linkage of the Cobra style and Alpha style work out? How about noise levels?

 

[TRobin9496]

Re: OMC Cobra Trim Cylinder Length

I'll post the reply to the other thread I started on the conversion issues so I don't have to respond to 2 different threads.

It's at: http://forums.iboats.com/showthread.php?t=403390