MC1 Trim Rams on Alpha 1 Drive - Problems

Cresco750

Petty Officer 2nd Class
Joined
Jul 7, 2012
Messages
192
Hi

About a year ago I installed a new SEI Alpha 1 style drive in place of my old MC1. I reused the original trim rams but in order to get the external hydraulic lines of the old style rams to clear the cavitation plate I had to rotate the outer cylinder 180 degrees. This caused the flexible lines to be put under some strain to the point where they did eventually kink as the drive has been tilted up and down. Yesterday one of them finally gave up and split, causing a fairly substantial leak when trimmed up.
Has anyone else had the same problem when reusing this style of ram when upgrading your drive?

The quickest and cheapest way for me to get back out on the water would be to simply replace the failed hose, but of course this will only fail again with time. I'm wondering whether I could fit a set of Alpha 1 rams instead, but would I run into problems with the hydraulic manifold of the MC1 transom assembly being slightly different? And the ram mounting pins are of a different size to the MC1 pins, so I would have issues mounting the different rams onto the transom assy (although I do have a big pin for the aft mounting)?

Cheers
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,082
Re: MC1 Trim Rams on Alpha 1 Drive - Problems

Hi

About a year ago I installed a new SEI Alpha 1 style drive in place of my old MC1. I reused the original trim rams but in order to get the external hydraulic lines of the old style rams to clear the cavitation plate I had to rotate the outer cylinder 180 degrees. This caused the flexible lines to be put under some strain to the point where they did eventually kink as the drive has been tilted up and down. Yesterday one of them finally gave up and split, causing a fairly substantial leak when trimmed up.
Has anyone else had the same problem when reusing this style of ram when upgrading your drive?

The quickest and cheapest way for me to get back out on the water would be to simply replace the failed hose, but of course this will only fail again with time. I'm wondering whether I could fit a set of Alpha 1 rams instead, but would I run into problems with the hydraulic manifold of the MC1 transom assembly being slightly different? And the ram mounting pins are of a different size to the MC1 pins, so I would have issues mounting the different rams onto the transom assy (although I do have a big pin for the aft mounting)?

Cheers

Ayuh,.... Got a picture,..??
 

Pete104

Lieutenant
Joined
Apr 30, 2011
Messages
1,439
Re: MC1 Trim Rams on Alpha 1 Drive - Problems

If you have "external lines" on your cylinders, they ain't original to the MC1 you replaced. The originals too those cylinders, all 4 hoses (2 per cylinder) came out the top front of the cylinder.

Pics would help a bunch!
 

Cresco750

Petty Officer 2nd Class
Joined
Jul 7, 2012
Messages
192
Re: MC1 Trim Rams on Alpha 1 Drive - Problems

image.jpg

Ok, hopefully I've managed to attach a pic of my current setup? With the original MC1 drive the hydraulic hoses entered the ram from the top, and the external line which ran to the back was underneath the ram. Because the SEI / Alpha drive has a larger cavitation plate the external line would hit the plate so i had to rotate the outer cylinder 180 degrees. As shown in the pic, this created a very sharp angle for the flexible hoses to route to the hydraulic manifold.

I've just found an old set of MC1 rams which have the internal lines which would fit straight on and solve my problems. Unfortunately, I can't seem to be able to get any movement in the cylinders when I push down on them, so does this mean that they would be junk, or just tight from sitting for years?

Pete, the rams pictured are the originals to this MC1 drive; as far as I was aware the MC1 came out with both internal and external lines on the rams, depending on the year of manufacture? I stand to be corrected.

Edit: Crap, sorry about the upside down photo - damn iPad!
 
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thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
Re: MC1 Trim Rams on Alpha 1 Drive - Problems

SEI sells new rams for $120 each. It is a lot cheaper than parts. I am not sure what is compatible but maybe they can help.
 

Cresco750

Petty Officer 2nd Class
Joined
Jul 7, 2012
Messages
192
Re: MC1 Trim Rams on Alpha 1 Drive - Problems

SEI sells new rams for $120 each. It is a lot cheaper than parts. I am not sure what is compatible but maybe they can help.

Yes, I'm considering that as an option, although that $120 quickly escalates once two rams are purchased, plus freight etc. Still, probably a good option. First of all though I'm going to try the set of used MC1 rams that I've picked up, which have the internal lines. I've freed them up ok but I'm still thinking that I should overhaul them with a new seal kit once I've trial fitted and tested them.

Is fitting new seals and internal cylinder a fairly straight forward job?

Cheers
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
Re: MC1 Trim Rams on Alpha 1 Drive - Problems

Yes, I'm considering that as an option, although that $120 quickly escalates once two rams are purchased, plus freight etc. Still, probably a good option. First of all though I'm going to try the set of used MC1 rams that I've picked up, which have the internal lines. I've freed them up ok but I'm still thinking that I should overhaul them with a new seal kit once I've trial fitted and tested them.

Is fitting new seals and internal cylinder a fairly straight forward job?

Cheers
It will cost you more in parts than SEI replacements. I did a lot of looking for my old boat.
 
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