2004 BF 225 leak under starboard thermostat

Hey everybody, need some help here.

After repairing a broken screw on the starboard side thermostat, we (a mechanic and I) started the engine to test things out. Well, water was leaking from the space between the block and the plate that the thermostat and timing belt pulleys are all mounted to. To be clear, water was not coming out from under the actual thermostat itself, there is a new O-ring and it seems to be working!

He filled the hole with a bunch of high test RTV (not the home depot kind!) and coated the screw in it as well before reassembling.

Anybody ever have this problem before. If so, what have you done? If this doesn't seep into the space between the two pieces, is my only solution to remove that top plate and rebed the whole thing?

As an aside, the repair I made to the cast on the port side thermostat last fall needs some attention as a little bit of water was seeping out. I read recently about drilling that out and tapping it, then putting a screw in - anybody try that? seems just as DIY as the steelstick!

Thoughts on both?

Thanks,
Chris

If you're in saltwater I suggest you remove the plate under the S/B thermostat, you do not want saltwater constantly running over your motor, bad idea. Nothing like fixing it properly, way cheaper in the long run

iang6766 said:

If you're in saltwater I suggest you remove the plate under the S/B thermostat, you do not want saltwater constantly running over your motor, bad idea. Nothing like fixing it properly, way cheaper in the long run

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Thanks for the follow-up...I agree that fixing it properly is the way to go for sure. I'm hoping that this would at least be a band aid for now. I haven't checked the engine yet today, hopefully this evening. There's no question, if water is still coming out, I'm going to pull the plate off. Is pulling that plate off a "big job" for a mechanic or nothing too crazy? From the looks of it, it doesn't seem like it should be that bad.

As long as you feel confident about refitting the cambelt, you should be fine

Good news - I ran the engine yesterday for 15 minutes, no leak. I cleaned up and repaired the hole on the port side today. Will year the engine again tomorrow and see where things stand.

Wasque said:

Good news - I ran the engine yesterday for 15 minutes, no leak. I cleaned up and repaired the hole on the port side today. Will year the engine again tomorrow and see where things stand.

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well I tested the engine again yesterday and she ran well, no leaks!

I plan to launch her today and stay local.

While I was at it, I ran some salt off thru to clean up the insides. Lots of bubbles but of course, hard to tell if anything came out as I didn’t have a bucket to capture all the water.