Mercruiser 3.0 No Spark issues

[alldodge]

I would say transom leak. Probably not the transom assembly though it might be. Most likely the transom is soft and needs to be replaced

 

[aidanmurphy]

I would say transom leak. Probably not the transom assembly though it might be. Most likely the transom is soft and needs to be replaced

Thanks. I will do some more investigating to see if I can confirm if the transom is in bad shape or not. It would make sense that the leak got worse after I pulled the drive if that is the issue. Anything I can do in the meantime to seal it better? Or is this a total no-go

 

[alldodge]

If its soft there is no easy fix.
Take a Philips screw driver and try to press it into the transom. ON SECOND thought DON'T DO THAT. My thought is its soft, and if you push a screw driver into the transom it may turn into a really bad leak

 

[aidanmurphy]

If its soft there is no easy fix.
Take a Philips screw driver and try to press it into the transom. ON SECOND thought DON'T DO THAT. My thought is its soft, and if you push a screw driver into the transom it may turn into a really bad leak

I did already try this from the inside right below the transom plate... it didn't budge with the screwdriver. There is a transducer mounted on the rear of the transom. I will pull this off and see if any water comes out of the holes... Transom tap test doesn't give any red flags either. I may try to tighten the nuts a bit on the inside if I can reach them. Unfortunate to make this discovery at the very beginning of the season if it is true..

 

[dubs283]

Looks like in the video around the 0:14 mark the water is leaking from above the trim lines. Thus would indicate a leaking exhaust system. Perhaps the o-ring for the exhaust tube/gimbal housing seal? Or the exhaust tube corroded through?
Could also be something above the exhaust.

 

[Bondo]

I may try to tighten the nuts a bit on the inside if I can reach them. Unfortunate to make this discovery at the very beginning of the season if it is true..

Ayuh,...... Those bottom bolts are aluminum, 'n do in fact, corrode in two,.....

 

[aidanmurphy]

Looks like in the video around the 0:14 mark the water is leaking from above the trim lines. Thus would indicate a leaking exhaust system. Perhaps the o-ring for the exhaust tube/gimbal housing seal? Or the exhaust tube corroded through?
Could also be something above the exhaust.

Hmm I can try to get another look at that... This could occur even with the motor not running?

 

[dubs283]

Hmm I can try to get another look at that... This could occur even with the motor not running?

Yes, if the boat is in the water.

 

[aidanmurphy]

Yes, if the boat is in the water.

Corrosion I would doubt... boat has been in freshwater all its life. I will have to put the boat in the water again and take another video / look at exactly where the water is coming from. All I know is that it is much worse after pulling the drive and doing the bellows. Would be worried to go out on the water with the bilge pumping every few minutes

 

[dubs283]

Corrosion I would doubt...

I wouldn't. Doesn't matter where the boat is used. Anything put in water will corrode given enough time. Add different elements to the mix to speed up the process. This is why there are different materials for freshwater anodes vs saltwater anodes

 

[aidanmurphy]

I wouldn't. Doesn't matter where the boat is used. Anything put in water will corrode given enough time. Add different elements to the mix to speed up the process. This is why there are different materials for freshwater anodes vs saltwater anodes

Thanks for the insight, will definitely look around some more

 

[aidanmurphy]

Went to tap around on the transom again.. dull sound and didn't get much bounceback on the lower left side of the transom on the outside of the boat. Assuming that is sign of rot and potential leak area.. The rest of the transom around the bell housing / bracket sounds good. Anything I could do to make it through the rest of the season before pulling the motor and doing the repair before next season? No flex in the transom itself from standing on the drive. The boat cruises around on a lake, spends most of the time anchored

 

[alldodge]

Good battery and bilge pump will keep it pumped out

 

[aidanmurphy]

Snagged a few photos of the lower bolts, looks like I could access them pretty easily to attempt to tighten them. They don't look corroded but maybe in the transom they are. Any objections to trying to tighten them a bit? Looks like the exhaust has a connection there too that could be leaking.. If I do tighten them would that call for a gimbal re-alignment?

 

[alldodge]

Tightening the bolts would not require rechecking alignment
Tightening the bolts may cause them to snap off IF they are corroded and have eroded internally. IMO, once something is old and starts leaking, tightening fasteners will have no effect

If the water is coming from the exhaust O-ring, tightening will not help

 

[aidanmurphy]

Tightening the bolts would not require rechecking alignment
Tightening the bolts may cause them to snap off IF they are corroded and have eroded internally. IMO, once something is old and starts leaking, tightening fasteners will have no effect

If the water is coming from the exhaust O-ring, tightening will not help

If I run on muffs would this be a good way to narrow the leak down to the exhaust o-ring or not.. if it leaks on muffs, it is the o-ring?

 

[alldodge]

If I run on muffs would this be a good way to narrow the leak down to the exhaust o-ring or not.. if it leaks on muffs, it is the o-ring?

Maybe, the issue is when its in the water and motor stopped, the pressure is increased inside the exhaust. Running on muffs has very little pressure.

To make it a bit safe, remove the exhaust boot and stick the hose down the exhaust pipe letting water run out with motor off

 

[Scott06]

If I run on muffs would this be a good way to narrow the leak down to the exhaust o-ring or not.. if it leaks on muffs, it is the o-ring?

Or ring or corroded down pipe . also i think if shutters get burnt and lodged in there you may wear a hole in the pipe.

 

[Scott06]

Went to tap around on the transom again.. dull sound and didn't get much bounceback on the lower left side of the transom on the outside of the boat. Assuming that is sign of rot and potential leak area.. The rest of the transom around the bell housing / bracket sounds good. Anything I could do to make it through the rest of the season before pulling the motor and doing the repair before next season? No flex in the transom itself from standing on the drive. The boat cruises around on a lake, spends most of the time anchored

Best bet is to drill holes in transom to see extent of rot.

 

[aidanmurphy]

Maybe, the issue is when its in the water and motor stopped, the pressure is increased inside the exhaust. Running on muffs has very little pressure.

To make it a bit safe, remove the exhaust boot and stick the hose down the exhaust pipe letting water run out with motor off

The exhaust boot on the elbow correct?