How to select correct SEI drive?

[matt167]

My dad has a 1970 ( I think ) Starcraft Offshore V 18 with Mercruiser 125hp I/O. The out drive went bad 2 years ago. Last year he bought a rotted parts boat and swapped the out drive onto it. The outdrive lasted 2 outings before filling itself full of water. I don't know if he just replaced the lower half or the complete leg. I wasn't there when he did it, and we haven't been out fishing in 3 years together. I don't know if the leg was any good to begin with, since it was off a junk boat. I don't even know if it is the right gear ratio.

I want to suprise him with a brand new complete SEI outdrive for Christmas. I know the drive he has may just need seals, but it may not be just that. SEI wants a serial number, and year.. I can't get the serial number without asking him and making him wonder.. However, I definitely know the gear ratio, the boat was made in 1970-1975 I would guess. I think I remember him saying '70 and it appears SEI just sends a special driveshaft with their " old style " outdrive. If I happen to order the wrong one, is it an easy change over?

 

[HT32BSX115]

I definitely know the gear ratio, the boat was made in 1970-1975 I would guess. I think I remember him saying '70 and it appears SEI just sends a special driveshaft with their " old style " outdrive. If I happen to order the wrong one, is it an easy change over?

Howdy,

I haven't seen a lot of people talking about SEi replacements for older #1 drives.. In this case, you should really call SEI and ask them. It appears their listed models are 1972 and later. They very likely have a work-around. If you need the serial number, go visit your dad and look for yourself so you get it right.


Cheers,

Rick

 

[achris]

Provided it's an MC1 and not an EZ- shift, nothing 'special' about the drive. You need an SEI 106, 1.94:1 ratio, with the short input yoke. That's it. If they don't have a short yoke, use the one from the old drive. Easy to swap.

If the hydraulic hoses come out at the bottom of the gimbal housing, it's an MC1. If they come out on the side of the gimbal housing, it's an EZ shift, and there's no replacement drive for it. Sorry.

Chris....

 

[matt167]

Cool. I'm 99.99% positive it is not an EZ shift. I know the boat is at least a 1970 and I'm 95% sure it IS a 1970

Weird. Sterndrivereplacement.com has it $100 cheaper than direct from SEI.. They lock the year listing at 1973 as earliest, but say it fits '67-'90 which makes sense..

I wish I could just go visit to get the serial, but he stores the boat somewhere else and it would be blatantly obvious what I was doing if I asked him where it was