Gear oil reservoir split open
 

Hi everyone. I'm new here. Typed a long post earlier about my gear oil reservoir cracking open but I did something wrong and the post didn't go. Boat is 4 years old. Serviced religiously. 117 hours. 6.2L Mercruiser. Bravo 1. No leaking cap on the reservoir like I've read in hundreds of post. All is good 1 minute then alarm blaring the next minute. Open the hood and have gear oil everywhere. Pop off a cover to expose reservoir and it's split across the top and down the side. It's a square reservoir with black top and translucent white box. Cap has seal and red rubber nipple. Oil was at the full mark when we started. Oil is new and what the book calls for. I change it at the end of the year every year for the last four years. Trying to figure out a cause and have only one indecent at the end of last year. I was backing in the trailer and my wife is on the boat pulling up to load up. She had a prop strike hard bottom in Lake Travis. Pulled the boat out. Very slight bend on one blade of the stainless prop. Skeg has two small chunks missing directly behind the prop. Got home brushed it off. Changed oils and tucked away for the winter. This cracked reservoir happened our first trip out. Could the prop strike have caused gears to misalign and over heat the gear oil enough to pressurize and rupture the reservoir? Could I be lucky enough to have a bad reservoir and just replace it and change the oil? For the short time we ran it there was no vibration or odd sounds. Just got home and haven't pulled the drain plug yet.

I tried to post a picture but it said I cannot until after I have 10 posts.

so post whore away till you get there :)

Nonsense is okay

Like this

didn't want to piss anyone off my first day here 🙂

4th post, getting closer but now it's time to go to work. we'll try again tomorrow. thanks for reply, at least I know it works.

We know you can do it :)

We have faith in you :)

5th

6th one

number 7

eight

9th post

number 10. hopefully pic is next

https://cimg6.ibsrv.net/gimg/www.off...66e3105360.jpg
here it is in all its glory.

don’t think I’ve ever seen that style drive oil resevoir…

with that being said, the cap as designed is a one way check valve. It’s supposed to let air in but not out so it is effectively pressurized. This keeps foaming down.

is it possible that the system over pressurized and broke the container. I guess it’s possible. I would definately pull magnets to see what they look like. Could also just be a manufacturers defect. If it’s warrantied I would ask for a replacement and see if it does it again.

You mentioned searching for similar failures. Assume you didn’t find anything?

a few years ago I had an issue with my newly built outdrives. They were heating up and turning the oil black. They ended up needing another rebuild but the point of the story is the resevoir never broke or ruptured. I would see the level rise a little but never blow off the top.

Ah, forget it. You pissed everyone off. :)

I searched in every way I could think and only kept coming across leaking caps. I was hopeful I would find some kind of service bulletin on a faulty part but nothing. my biggest concern is replacing it then it happens again and causes some drive damage. going to go talk to the boat people today and see if they have any info. Magnets coming out tonight.

SB thanks for the encouragement!

Someone step on it, or partially ? Looks like a false invite for a toe hold.

Its pretty well in a safe spot. Have to open the back to get access to it. I'm having a hard time in thinking it could have over pressured because the box itself doesn't look like it swole up. Oil just leaked on a belt and got slung everywhere. Maybe a belt frayed and slapped it! I'll check that out in few minutes.

Good luck with the detective work
and the fix once figured out

Went to the mechanic. Explained everything and he told me it's most likely brittle plastic. Screw it. I'm going to order the parts and just do it and see how the next trip goes. If it pops again then I know there is more of an issue. Question. Has anyone ever ran out of water on muffs long enough to get the drive warmed up? I've ran only a few minutes before and after oil change but I want to run in gear and see if I can get pretty warm.

you will not be able to heat the drive up on muffs…there is no load running thru gears or bearings. As such, nothing to create heat. You can spin your prop for hours probably without generating much heat.

Thank you 1Moses1. Will test at the water after repairs. Got everything ordered and now we wait. If this thread is still open I'll post after our next trip on what the end results are. Thank you all. Have fun out there.

Why need to 10 post for pics

same issue with 10 post

Bots usually get figured out and kicked off before 10 posts.

boat was new 4 years ago. drive is the original one. port side pic and starboard side pic. can you spot the difference?
https://cimg6.ibsrv.net/gimg/www.off...edd1c5d360.jpg
https://cimg7.ibsrv.net/gimg/www.off...b9b069556d.jpg

Not very obvious, but I see at least a minor detail difference between your #One and #Two pictures.

you got it. wonder how and why I got a 1 and 2. or is that how they all are? its a 1.

lol! You might have a valuable asset there!
As for the cap, it certainly seems like it was just weak? I'd agree that it was stepped on or something like that...

did the repair today. drive did get hot and cooked the oil. plastic reservoir was brittle. trying to get the hose off the bottom of the thing the hose barb broke off with ease. I think brittle box plus overly hot oil ruptured it. it's not in a place to get stepped on. I'm the only person that opens the engine bay and have never walked in the engine. also installed drive shower and new prop. Old prop had slight ding on 2 blades. anyone know a good stainless prop repair guy? heading to the lake this weekend. put it through the paces and post an update after. sorry to get long winded but I love being on the boat, working on the boat, and talking about the boat 🙂

you showing pictures of both drives prompted me to think of something…does the side that ruptured seem like it has cooked outdrive paint? Usually if the drive is getting hot the paint will dis-color. It might not be so obvious if it has the simrek drive showers.

it's a single drive. it has a bravo 1 and Bravo 2 sticker on the single drive. yes it got hot. had a light white coating on the upper. just installed the shower today after draining old oil and flushing until complete clean oil drained out. no metal, no water. very hopeful I got lucky but will find out this weekend. has never got hot before. if it gets hot this weekend the drive is coming off and getting inspected/serviced. not sure if I can do that myself but will most likely try.

Final update on the cracked open gear oil reservoir. After putting in a new one, several flushes, and drive shower install, everything appears to be back to normal. Ran on it pretty hard today. About two hours of towing my girls around on a tube, couple of drag races against my buddies Malibu, and a long cruise at 40mph, had zero problems. Stuck my finger in the reservoir several times just to see if the oil was hot and was barely warm. Time for wash and wax. Be safe and have fun out there. 😎

hoping for you it doesn’t happen again…I would keep an eye on drive oil color, magnets, noise, and shifting.

fyi: feeling temp of resevoir is pointless. There isn’t any real exchange between drive and bottle. Not a good indicator.