My M 28 w/ 2GM 20 F has been out of the water in 8 yrs, and I assume the shaft log is original. I hesitate to launch w/o maintenance to the seals. https://www.munacosealing.com/products/klozure-mechanical-seals/syntron-rp-mechanical-shaft-seals says they have repair kits, which can be installed in the field. I have checked the posts, and find nothing on this. Has anyone had experience w/ this? I don’t want to pull the shaft and possibly damage the seals without having a repair handy. I will contact the company next.
Thanks, John
In 2019 I decided to replace the Syntron Shaft seal with a Norscot Shaft seal for at least half the price ($350) of a Syntron seal rebuild kit. Plus the lead time was longer than I could tolerate. It is a good seal but requires external lubrication from a reservoir using transmission fluid. I figured this would be better than using seawater lubrication as it would be much cleaner and less corrosive. So far I am happy with it. Tight fit but was able to get it in with room to spare. Freedom started using this shaft seal on some of its newer models back when in production.
Do not install a Norscott seal as when it fails it dumps transmission oil into the ocean.
Contact Warren boat Works for a custom cut dripless seal.
You shouldn’t need a custom shaft seal. The PSS shaft seal has worked great for me.
– Geoff
[quote=GeoffSchultz post_id=54252 time=1642628747 user_id=53]
You shouldn’t need a custom shaft seal.
[/quote]
It’s not a custom shaft seal, just a modified version of the Tides Marine seriesOne seal. The hose for the seal is cut down slightly, I think, so that it will fit in the very small space between the engine and the stern tube. From what I understand, a PSS seal won’t fit in most Freedoms, which is why they went with the Syntron, and later the Norscot. I have had both a Norscot and a Tides, and the Tides seal is so much better.
The main problem with the Syntrons, which were selected by Gary Mull when he was designing the F36, is that over time the graphite in the seals wears grooves into the shaft where they make contact. It will start to leak, and the owner will think the seal needs to be rebuilt, but the problem remains because the shaft is damaged. I believe this is what prompted the switch to Norscot.
My yard was able to install a PSS shaft seal on my 35. I’ve done the job on another boat, but it looked like a very tight fit so I let them do it. They said it took longer than expected, and I can believe it.
I have a P 35 - on my second pss shaft seal. No problems. Uncompressed length of the seal is approx 6 3/4”. Compressed is less 
Measure and check your available room….
Thanks for all the useful info, I will check all the options, starting with Warren River Boatworks, which I didn’t know about.