Showing results for 
Search instead for 
Did you mean: 

420 AC Stern Glands

Guest Contributor

Hello again 🙄. Looking as usual for some help. We have water coming in from our stern glands. I know a few drops is ok but this is more like a fast trickle. Can you adjust/tighten this yourself with the boat in the water or should it be left to the professionals. Thanks once again for anyone who can help. 






Rising Contributor

Hard to tell from the image.

FWIW, the Tides Marine dripless seal carrier used on many Sea Ray boats has two required tests that should be performed periodically.

One is to disconnect the hose and use the existing fitting cap. With the engine at idle measure the raw water provided by the engine to the dripless seal carrier and compare the required specification.

The other is w/ the engine off and the cap removed to measure the raw water intrusion, backwards through the dripless seal carrier and also compare to the required specification.

Note that on my boat, even though it is theoretically possible I would never consider that service in water unless faced with an emergency repair. If at all possible I would do that on the hard. Remember to do the in water tests first to ID any potential problems that cannot be verified when the boat is on the hard.

Sorry in advance if some or any of this is not applicable to your boat.

FWIW, I always turn my own wrenches on the boat. This is definitely a DIY project for me.

Hi Wingless sorry for the late reply but I’m just back from Croatia preparing the boat to be lifted on to a ship and taken to Gibraltar where I’ll re pick it up and sail it to Spain. To complicate things further, I live in Scotland 🏴󠁧󠁢󠁳󠁣󠁴󠁿 🤪. Thanks I’ve now read up on these devices and I reckon it’s the dripless seal that needs replacing. There seems to be loads of YouTube videos with guys doing this in the water but you seem to advocate it be done on hard standing. Is that correct? I was also wondering where the engine gets the water from. Is it from its own violent or fresh water from outside the boat. I have never had such a device on any shaft boat I’ve previously owned. Finally would you know the diameter of the shaft in these 420’s so I can preorder the seals for my next visit. Had I half a brain I should have done this when I was out🙄🙄. Thanks so much for taking the time to reply. I can assure you it is very much appreciated. Best Liam 

Rising Contributor

That 1997 420AC yacht likely still has the original Tides Sure Seal dripless seals.

If so, then that is an old design and those parts have been used past the expected service life. Those parts should be replaced w/ current technolgy parts, such as the Tides Strong Seal. Assuming the Tides brand is retained then the (likely) existing spare seal can be retained. When I do the seals on my boat I put the spare as active and the new as a spare (the current seal is discarded).

Yes, it is theoretically possible to swap seals on a floating boat, assuming that it already has a spare on the shaft, but that is not something I would ever attempt.

My 2000 380DA has 1½" shafts. My guess is yours has 2" shafts. The fine people at Tides can tell you exactly what parts are required.

The engines draw in raw water (sea water) for cooling everything. That raw water circuit has a tee fitting to provide these dripless seals w/ pressurized raw water when the engines are running. Again, it is VERY important to perform those two tests annually to ensure this critical system is good.

Sea Ray built my boat w/ dripless seals having a single hose barb for pressurized raw water. When I upgraded those parts I switched to dripless seals having two hose barbs so I could add a crossover hose. That crossover hose permits boat operation w/ only one engine running. 

Thanks for that. I’ll check it and hopefully get it done in Gibraltar. Appreciate all your help and advice…yiu might hear from me again 🤪🤪