Saildrive partial blockage

[Jacana]

Would like hints on cleaning critters out of SD25 sail drive raw water passage ,also is it feasible to unscrew raw water tap from saildrive while boats in the water .Thanks Geoff.

[requiem]

When I had a similar blockage I took a dinghy inflation pump, stuck the tube into the incoming port of the raw water strainer and pumped until it was clear. It was a bit kludgy and if doing it again I'd look for a way to make a better seal with the pump.

[chrisr]

no, it's not possible - the water ingress will be almost impossible to manage. we tried it once and regretted it

although i suppose this depends upon how deep your bilge is and the capacity of your bilge pump

it's basically something that needs to be done out of the water, although a good diver can do a lot of work with a piece of stainless wire

if you have over-heating problems, are you sure it's a blockage at the saildrive ?

finally, one of the things i've done to most of my boats is seal up the water suction on the saildrive leg (which are prone to blocking), and install a proper sea suction

cheers,

[skipperpete]

I had a tricky overheating problem with a yanmar, only a small/tiny amount of water was coming through the Saildrive so it was temporarily connected to a thru hull and weeks later hauled out to find the problem.......and it wasn’t shell in the leg passageways, it was a plastic bag that had made it all the way up to the annular waterway where the leg bolts to the gearbox. I took a photo of it packed into that tight space, I’ll post it when I find it in the engine files.

[skipperpete]

And here’s the blockage. I was never so happy to see a plastic bag. [ATTACH]268503[ATTACH]268504

[SVNeko]

This is a persistent problem and you need to be sure to clean them thoroughly at every haulout. Ultimately we drilled a hole near the saildrive (monolithic bottom), added a seacock, tee'd into the raw water line and problem solved.

[skipperpete]

SVNeko , regarding your thru hull mod, I was going to mention that during the period of time that the engine was not drawing raw water through the saildrive there was no appreciable change in gear oil temp so for me, this probably settles the theory that without water flowing through the Saildrive, the gearbox oil would overheat although I’m prepared to accept that it might if the cone was slipping......
And for anyone mysteriously losing oil out of, or getting water into an SD50 Saildrive, that black oring in the pic can be the culprit.

[Jacana]

Problem now solved. I connect garden hose inside engine room onto saildrive water inlet tap and ran water down saildrive while using wire underneath saildrive poking it up inlet managed to dislodge mussel shell that was causing blockage as now plenty of seawater running to impeller pump.Amazing what a little poke can do.
Thanks for all advice, safe travels and Happy New Year from Australia.