MC-1 Cylinder Rebuild Questions

[ttownthomas]

My transom assemblies are in, motors being installed this week and I will start re-rigging this Boat soon.

I pulled the rams, which were working, out of a box and decided to consider re-sealing them and cosmetically refurbishing them. I have only pulled 1 open but in this first case the outer sleeve did not pull out with the ram.

Is there a method to pulling it without marring the surface? Other than the FSM, what resources should I be looking at?

ram - 1 by ttownthomas, on Flickr

 

[kenny nunez]

When you remove the lock nut be very careful as there are small springs on either end and the check valves are in 2 pieces, be sure they go back on the way they come off. After the valves are off remove the rest of the parts from the rod. Screw the cover nut on the ram tube and bang it on the table. The tube should come out with a small spool that also has “O” rings. Some times the small spool takes a few more table bangs. Rebuild one at a time, compressed air in the ports will test the ram in both directions.

 

[ttownthomas]

When you remove the lock nut be very careful as there are small springs on either end and the check valves are in 2 pieces, be sure they go back on the way they come off. After the valves are off remove the rest of the parts from the rod. Screw the cover nut on the ram tube and bang it on the table. The tube should come out with a small spool that also has “O” rings. Some times the small spool takes a few more table bangs. Rebuild one at a time, compressed air in the ports will test the ram in both directions.

Got it. Thanks!

 

[ttownthomas]

Yikes. I cant believe how expensive the rebuild kits are....I assume I can use the specs from the FSM and order compatible o-rings someplace? I dont know much about o-rings. There appear to be many different materials they are made from. How do I choose?

 

[ScottinAZ]

Yikes. I cant believe how expensive the rebuild kits are....I assume I can use the specs from the FSM and order compatible o-rings someplace? I dont know much about o-rings. There appear to be many different materials they are made from. How do I choose?

some of the o-rings arent o-rings per se, but are quad seals, where they have almost a square profile with rounded edges. a hydraulic shop may be able to assist you, but these rams are pretty small and specific in their usage. If they have the right sizes, they will have the compatible materials as well..... its just a light hydraulic oil (I used power steering fluid in mine, as its clear, so I can ID a leak for where it came from, and it meets the viscosity requirements)

When I redid mine, I was able to find some NOS kits on eBay for less than what most retailers want for them. Its not a "cheap" endeavor, but if done right, will only have to be done once. I will second the above poster on the check valve...... You DO NOT want that coming apart on you, the balls and springs are miniscule, and will go everywhere. I ended up needing a "donor" cylinder to scrounge the parts out of when mine went into the alternate dimension where the lost socks from the dryer, and that missing pocket change from the couch end up........

 

[ttownthomas]

Thanks for the tip on the quad seal. I assumed square o-ring. Mabee I'm wrong (or being arrogant) but it seems like brand new seals, if I can find the right sizes and types (I have found an o-ring retailer online), would be better than 20+ year old ones.... It looks like the very aft seal is actually a rod scraper

 

[ttownthomas]

Ok. I have sourced all the seals. They are very inexpensive (other than the rod scraper) which is like $50 apiece. Just need to triple check my measurements. Should nitrile 70 seals be good all around?