Leak into bilge, bellows?

[gsbarry]

First time taking out a new to me boat today. 2015 Bayliner 175 i/o. Drove the boat for about an hour and noticed a small amount in the bilge, maybe 1” or so. Boat sat at the dock for 4 hours and thankfully I checked, bilge was pretty much full, maybe 6”.

It wasn’t obvious to me where the water infiltration was coming from. What do y’all think is the most likely source, bellows? As far as I know, the bellows are original. I visually inspected the bellows when I had the outdrive off recently, and the rubber looked really good, no signs of cracking, so I didn’t replace despite being 10 years old.

 

[Scott06]

First time taking out a new to me boat today. 2015 Bayliner 175 i/o. Drove the boat for about an hour and noticed a small amount in the bilge, maybe 1” or so. Boat sat at the dock for 4 hours and thankfully I checked, bilge was pretty much full, maybe 6”.

It wasn’t obvious to me where the water infiltration was coming from. What do y’all think is the most likely source, bellows? As far as I know, the bellows are original. I visually inspected the bellows when I had the outdrive off recently, and the rubber looked really good, no signs of cracking, so I didn’t replace despite being 10 years old.

It could be bellows either driveshaft or shift. could also be exhaust pipe. Need to put it in the water and see where it is coming in . Bellows can leak or not leak depending on out drive trim and where the steering is positioned.

fresh water use my bellows were not leaking at 18 years old when I changed them But that doesn’t mean yours are not. Is garboard plug housing leaking ?

 

[gsbarry]

That’s a good point about trim. At the dock I had to have it fully trimmed up due to shallow depth, and it appeared to me the rate of water intrusion was higher sitting at the dock, rather than when driving on the water trimmed down. This does point me to bellows.

It’s such a tight engine compartment I can’t physically get my head to the back of the motor to see if the plug is leaking, although I didn’t see water leaking OUT of the plug once on trailer, if that’s any indication. I’ll have to remember to bring my mechanics mirror next time I test it out.

 

[Scott06]

That’s a good point about trim. At the dock I had to have it fully trimmed up due to shallow depth, and it appeared to me the rate of water intrusion was higher sitting at the dock, rather than when driving on the water trimmed down. This does point me to bellows.

It’s such a tight engine compartment I can’t physically get my head to the back of the motor to see if the plug is leaking, although I didn’t see water leaking OUT of the plug once on trailer, if that’s any indication. I’ll have to remember to bring my mechanics mirror next time I test it out.

Bottom line with a scope Carmera attchment etc you need to get back in there and look that’s the only thing that will show you this.
lift drive full out and double check the bellows both driveshaft and shift. The driveshaft can get splits on the side where it rubs on gimbal ring. Can also pull the drive and see if water is in the bellows as you don’t want it to sit there

 

[gsbarry]

I was able to confirm today using a borescope that the leak is indeed the shift cable bellows.
It only leaks noticeably when the trim is up.
I also noticed some backflow through the bilge pump when the water laps up, I think I’ll be installing a check valve (and a float valve, as I learned there isn’t one from the factory on this boat).

 

[Scott Danforth]

With any new to you boat, you really should do all the maintenance the prior owner didn't do

 

[bajaman123]

As Scott D above notes...NOW is the time to do all the PMs that the previous owner likely didn't do whilst you are fixing the shift bellows leak. Only a matter of time before the other bellows start leaking. Take the outdrive off, lube the u-joints, replace all the seals, bellows, etc. Go ahead and do the impeller for good measure. Check and adjust all your cables, look closely at all wire runs, tidy up with clamps or zipties as needed.

 

[gsbarry]

Thanks y’all, agreed. I had already pulled the outdrive and replaced impeller, as well as a couple of melted parts (oil seal carrier and water tube) in the outdrive. I inspected the bellows visually at the time, but didn’t catch this leak. Can’t be too surprised that 10 year old bellows leak. I’ll be replacing all 3 while I’m in there, with the Quicksilver kit, and all the other parts it includes (seals, o rings, gimbal bearing, etc) I had also checked the alignment and checked the gimbal bearing, which were good. Do y’all typically have to put a torch on the hinge pins to get them to break free? Any brand/part suggestions on check valve and float valve for the bilge pump?

 

[cyclops222]

I would relocate the bilge pump outlet hose. To a much higher outlet on the transom. Allow for a full load of the boat to determine where the outlet should be. Check valves can stick open. I do the higher outlet hose way.

 

[gsbarry]

I'm a bit confused on the correct repair kit part number. Some sites list this as only for 91-97 serial number gen ii's, but the Mercruiser catalogue has the same kit ("bearing repair kit") under the 98 and up as well. I can see the main gasket has the oil reservoir hose hole in it.

 

[Scott06]

I'm a bit confused on the correct repair kit part number. Some sites list this as only for 91-97 serial number gen ii's, but the Mercruiser catalogue has the same kit ("bearing repair kit") under the 98 and up as well. I can see the main gasket has the oil reservoir hose hole in it.

View attachment 405590View attachment 405591

pretty sure the bellows kits and gimbal bearings are the same for all Gen 2 drives. The reason for the listing breakdown at 98 and up /97 and older is they changed the input shaft bearing arrangement and ujoints. Went from and internal to external retaining ring on ujoints and the bearing pack on input yoke is different requiring tighten to rolling torque spec vs tighten to ft lb spec.

This is why you can see the same kits list for two different drive revisions.

Stay with the OEM parts here they are worth the price. My 2004 boat I just did the bellows after 18 years. Exhaust bellows (which doesnt matter) tore but shift and driveshaft were just starting to show some wear.

 

[Bt Doctur]

Incorrect, main bellow is specific for Alpha and alpha gen I
alpha has clamps at both ends, gen II uses 1 clamp and 1 sleeve

 

[Scott06]

Incorrect, main bellow is specific for Alpha and alpha gen I
alpha has clamps at both ends, gen II uses 1 clamp and 1 sleeve

91 and up is GEN2 right? I was just talking about all Gen 2 drives not the older drives

 

[Chris1956]

BTW- the exhaust bellows will not leak water into the boat if it has a hole or crack. It is sealed to the manifolds, which are also sealed, until above the waterline. A lot of Gen 2 drives come with an exhaust tube, rather than a bellows.

 

[ESGWheel]

American Boat & Yacht Council (ABYC), the standard setting forum, does not recommend using a check valve for bilge pumps More than sticking open the concern is they will stick closed or become clogged precluding dewatering. The backflow of water you noticed at the bilge pump may just be normal > when the pump is running it will discharge as expected and then when it turns off, there is some small volume of water in the hose that will ‘backflush’ into the bilge > a cup or two. This is normal.

Also, you mention a float valve > your bilge pump may already have a self-contained switch that will turn on the pump automatically. Look at its wiring harness. If it has 4 wires it already has an auto feature. If only 3 wires, then no auto feature.

In either case you should always test the pump during the season start up checks. Put in the drain plug and fill the bilge with water (while monitoring the level). If an auto it should come on when water is about ½ way up the pump. I then check its manual operation as well. If only manual type use about the same fill level and turn on the pump.

However, if your bilge pump output is just above the waterline when the boat is normally loaded up potently allowing water to flow into the boat, then as Cyclops suggests, find a higher spot.

Here is a comprehensive article on bilge pumps that is a good read (link).

 

[gsbarry]

Thanks for the advice/info. Current bilge pump is manual only (no float valve). I’ll steer clear of check valves. I noticed the hose loop could be a bit higher if I replace/extend the hose, might do that. I’m also thinking about adding a secondary pump with an integrated float valve, looking at the Attwood Sahara s750. The idea is to have redundancy and automation when unattended (boat will normally be trailered, but expect to do some overnight mooring), meaning not to run both pumps at once. Is it bad design to plumb both pumps into one hose utilizing a single through hull fitting? If this is acceptable, how does one avoid water pumping back down the pipe to the non-running pump without using a check valve? Perhaps rout separate hose loops, then use an obtuse angle y-fitting downstream of the loops so as to make the water dynamics optimally flow out (if that makes sense)?

 

[gsbarry]

Separate question, looking for tips on the shift cable installation procedure as part of the bellows replacement. My issue is one of visibility and access, very difficult to reach down behind the motor, let alone see, due to the design of the engine bay, without pulling the motor. Any tips for this kind of situation? I was thinking I could try tying off a piece of string or wire to the shift cable as I remove it, but my concern is that the knot will create too much interference to clear through the plastic cable fitting in the transom (which I would prefer not to remove given how impossible it is to reach down there). Perhaps just the right knot in just the right place would work?

 

[ESGWheel]

This a bit of a crossover and may warrant another thread, but here goes > Dual bilge pumps are a good idea for moored boats. I plan on installing a 2nd in my boat this spring (23’ Bowrider). BUT need to use separate discharges (two outlets). Set them up so they come on a different water levels.

No idea on the cable replacement. Suggest start a new thread with title: “Need help on shift cable installation”

 

[nola mike]

Separate question, looking for tips on the shift cable installation procedure as part of the bellows replacement. My issue is one of visibility and access, very difficult to reach down behind the motor, let alone see, due to the design of the engine bay, without pulling the motor. Any tips for this kind of situation? I was thinking I could try tying off a piece of string or wire to the shift cable as I remove it, but my concern is that the knot will create too much interference to clear through the plastic cable fitting in the transom (which I would prefer not to remove given how impossible it is to reach down there). Perhaps just the right knot in just the right place would work?

Good that you asked this ahead of time. When you remove the shift cable, thread something else through (I use weed whacker line) and tie it off somewhere convenient in the engine bay. Remove the cable housing, and thread new housing over the weed wacker line. Lots of information about this if you search.

 

[Scott06]

This a bit of a crossover and may warrant another thread, but here goes > Dual bilge pumps are a good idea for moored boats. I plan on installing a 2nd in my boat this spring (23’ Bowrider). BUT need to use separate discharges (two outlets). Set them up so they come on a different water levels.

No idea on the cable replacement. Suggest start a new thread with title: “Need help on shift cable installation”

Mike has you straight on the shift cable

The bilge pumps what u outline is good would also consider battery capacity most of the time when it sinks the bilge pump comes on enough to drain battery so would consider adding a second battery and charging either solar or shot