Lyndy
Chief Petty Officer
- Joined
- Oct 15, 2006
- Messages
- 437
Learning curve never seems to end. I am almost through with refurbing my Outdrive. I think OMC paid attention to how Volkswagon built there Bugs back in the 50's and 60's, making a number of parts interchangeable. So here is the history of what I have found:
1) Upper Gearcase is likely late sixties, but with a 21/17 gear ratio which is from the early to mid 80's. From a previous post about the pump drive shaft and upper drive shaft fusing together, that has been resolved with a re-build of the Gear Case, which at the same time the 21/17 is being replaced with a 21/16 Gear Set. I lucked out on this one, no broken parts and it cost me $300. I got off REAL EASY!
2) Original Lower Gearcase that came with the boat is also likely from the late sixties. It only have one Zirk fitting on the Swivel Housing. This Lower Unit I still have. It was left behind after I insisted it be replaced before I bought the boat. (Small amount of Oil on ground directly under the drive). Replacement Lower Unit has 2 Zirk fittings on the Swivel Housing which puts it closer to the mid seventies. Although he replaced it with a newer unit, he failed to install the second Zirk fitting which might explain why their was so little grease in the housing when I removed the Upper Gearcase. Replacing The Swivel Housing with another one that has good seals and at the same time replacing the Electric Shift Cable with a new one. When the owner replaced the Lower, his mechanic simply cut the Shift Cable and spliced the one on the replacement lower with the existing cable.
3) The Rudder on the older Lower Unit was put on the replacement. It too was from the late 60's
4) Exhaust Housing has no place for a Label Mount and has a blocked off mount for a Steering Rod. Again, typical of a unit in the late 60's.
I will no longer be saying I have a 1975 OMC Drive, I will refer to it as a 68-76. So now with a OMC Drive and a 1998 5.0 Mercruiser Engine, not only do I have a Junkyard Dog Power Plant, the Drive is a definite Mongrel.
The adventure continues
1) Upper Gearcase is likely late sixties, but with a 21/17 gear ratio which is from the early to mid 80's. From a previous post about the pump drive shaft and upper drive shaft fusing together, that has been resolved with a re-build of the Gear Case, which at the same time the 21/17 is being replaced with a 21/16 Gear Set. I lucked out on this one, no broken parts and it cost me $300. I got off REAL EASY!
2) Original Lower Gearcase that came with the boat is also likely from the late sixties. It only have one Zirk fitting on the Swivel Housing. This Lower Unit I still have. It was left behind after I insisted it be replaced before I bought the boat. (Small amount of Oil on ground directly under the drive). Replacement Lower Unit has 2 Zirk fittings on the Swivel Housing which puts it closer to the mid seventies. Although he replaced it with a newer unit, he failed to install the second Zirk fitting which might explain why their was so little grease in the housing when I removed the Upper Gearcase. Replacing The Swivel Housing with another one that has good seals and at the same time replacing the Electric Shift Cable with a new one. When the owner replaced the Lower, his mechanic simply cut the Shift Cable and spliced the one on the replacement lower with the existing cable.
3) The Rudder on the older Lower Unit was put on the replacement. It too was from the late 60's
4) Exhaust Housing has no place for a Label Mount and has a blocked off mount for a Steering Rod. Again, typical of a unit in the late 60's.
I will no longer be saying I have a 1975 OMC Drive, I will refer to it as a 68-76. So now with a OMC Drive and a 1998 5.0 Mercruiser Engine, not only do I have a Junkyard Dog Power Plant, the Drive is a definite Mongrel.
The adventure continues
