Merc. lower unit project

[Water Romper]

Though I would post my up-and-coming saga regarding my lower unit, maybe other RD folks might find it interesting and helpful.
To start, I am not a mechanic, i don't live anywhere near Lake Havasu, I am in Boise, Idaho. I am not rich and have limited funds/budget for boating. I know the nay-sayers and bashers may have a good time with this- but it's the route I chose to take.
The motor: 1992 Merc 150 Blk Max, 2 stroke, oil injected, stock-nothing fancy but runs good and fast.
The boat: Hallett 19ft. Sport Skier, original Barron boat from Irwindale, CA.

Here we go-
Near the end of last summer, launched the boat, put the boat in gear to pull away, felt a grinding vibration, chugged and felt terrible, took it out of gear, motor ran fine- water "peeing" good, slipped it back in gear (hoping for some kind of miracle) same thing. I was a foot from the dock so that was the end of my boating for the season- I DID NOT HIT ANYTHING so I figured I scattered the gears etc. Drained the gear oil, no signs of damage/shavings, no water- Hmmmm

Dropped the lower, no signs of damage at the top of the spline (whew) So I take it to the local Mercury dealer/mechanic here in Boise- its a large shop, huge Merc dealer and repair shop.

Mechanic was totally cool- right then and there, he dismantles the whole lower unit, this would have taken me hours, took him 10 minutes. Pulls the whole damn gear clusters out and they look brand new, Clutch dog- perfect, oil, nice and clean. And then...there is was, the bearing went bad, he stated "good thing I didn't continue running the boat" Im thinking I dodged a bullet, after all, how expensive can a couple bearings be.

Here were my options:
1) New or newer motor- $10-$20 thousand dollars- No way
2) New Merc lower unit- $4500.00- 30 day warranty- No Way
3) Have the mechanic rebuild my unit- using OEM parts- $900 to a thousand dollars- 30 day warranty- possible option
4) Purchase a new lower unit from SEI- $1150.00 3 year unconditional warranty EVEN IF I HIT SOMETHING they will replace it - Yes, is it China crap? Is SEI known for good/bad lowers? I did some research and to be honest, the reviews were not that bad, guess they had some issues back in 2017/2018 etc. but even the mechanic says they use SEI all the time with good results. So I purchased the new lower. Also, I may be able to recoup a few bucks selling my non-working lower, we will see.
Here are the few things that will void SEI's warranty: Cant be a professional fisherman (bass guy i suppose) Cant be used as a business , cant be used as a commercial fisherman

I have NOT received it yet- I will post my saga with pictures once the unit arrives and post the install, break in and (hopefully) no drama and just fun, reliable boating.

Had I been in Havi or even in Southern Cal, I may have had different options but it is what it is- I know many RD folks would just rebuild it them selves, buy a new motor or just go get a new boat- well, I'm not that fortunate, I have to deal with what I got.

So take this post for what its worth- good or bad. Thinking maybe a few other peeps may find the SEI route an option if they are in the same predicament.

 

[Reaper1]

Good info. I hope everything works out for you, and you can enjoy some "no drama and just fun, reliable boating" because that's what it's all about.

 

[RCDave]

What shop is it? Looking for a good shop in Boise

 

[Water Romper]

Idaho Marine​

www.idahomarine.com
4000 W Fairview Ave, Boise, ID 83706
(208) 342-0639

The mechanic was named Mark- Apparently, he is about to throw the towel in (retire) and move to (I think Prescott, AZ) Totally nice guy, reminds me of a mechanic I had service my Carrera at Cat Tail Cove years ago- Big John I believe was his name. Anyway, Idaho Marine is a full-service shop, new/used boats, store and parts supply. No Havi style boats but for parts and "over the counter" stuff etc, they seem to be pretty well stocked.

 

[RCDave]

Thank you! I give then a look

 

[HST4ME]

Been doing gearcases for over 30 years. You are much better off with a rebuild.

 

[Water Romper]

Been doing gearcases for over 30 years. You are much better off with a rebuild.

This may be true- but a rebuild has a 30-day warranty, the SEI has a 3-year unconditional for about $100.00 more. I guess we will see if I made the right decision. As a side note- It snowed last night AND the local lakes are cutting back on water so boating season will be cut short, this means my "warranty" will be used up even as the boat just sits. This picture was last week and the level the lake will be at for the summer. Not looking good for boating this year.

 

[MPHSystems]

This may be true- but a rebuild has a 30-day warranty, the SEI has a 3-year unconditional for about $100.00 more. I guess we will see if I made the right decision. As a side note- It snowed last night AND the local lakes are cutting back on water so boating season will be cut short, this means my "warranty" will be used up even as the boat just sits. This picture was last week and the level the lake will be at for the summer. Not looking good for boating this year.

View attachment 1114074

You’re lake sucks. I don’t see a single dead body barrel.

 

[mash on it]

You’re lake sucks. I don’t see a single dead body barrel.

Classy.

Dan'l

 

[rivermobster]

Your logic makes perfect sense, considering all the costs involved.

But I'd keep your old gear case if I was you. You may need it down the road. They aren't that hard to rebuild. You can take your time and do it yourself for very little cost.

 

[Luv2gofast]

Your logic makes perfect sense, considering all the costs involved.

But I'd keep your old gear case if I was you. You may need it down the road. They aren't that hard to rebuild. You can take your time and do it yourself for very little cost.

I agree. I've seen SEI's work and have seen them fail. They have a 3 year warranty because they were getting a bad name and figure you won't bad mouth them if they give you another one. Bearings are made to very close tolerances so if nothing else got hurt it's an easy fix and won't require setting up the gears. Good to have a spare!

 

[ChrisV]

I'll rebuild it and save up for another OEM lower. Seems like lower units goes out all the time. Can't go wrong with a spare.

 

[Water Romper]

You’re lake sucks. I don’t see a single dead body barrel.

HaHa, I doubt there very many bodies in this lake, unlike Mead, this "lake" gets drained every year- amazing how the water regulators fill it up and then empty it like a bathtub. And know it's not a small lake (reservoir) In its own right, it's a beautiful place to boat (when full) but even in Southern Idaho the drought has reared its ugly head. Crops and agriculture are more important than boating in these parts.

 

[Water Romper]

The idea of keeping a "spare" is good. The only thing that makes me shy away from re-building my own lower is the whole "shim" thing, apparently this is what can make or break a good re-build. Probably like everything else in life, do it once or twice and it makes sense. I may give it a shot this summer, who knows, I may surprise myself.

 

[Luv2gofast]

The only thing that makes me shy away from re-building my own lower is the whole "shim" thing,

Which bearing failed. Like I said above, the gear set-up (shims) probably won't need to be changed.

 

[HST4ME]

Anytime you change a part you have to check all the tolerances. In 30+ years of doing this I have learned ways to "cheat" around, But it still involves all the set up tools. I've made SEI cases with a nose cone live under a 300x on a bullet bass boat for years. There have been brand new Mercury Sportmasters I've had to tear down because the assembler spent the night at the cheese and beer bar and failed backlash 101. It's a lot of patience doing lowers and outdrives, and helps to have a dry ice supply around too.

Properly done a lower will last a long time. I still run the cle I bought under a new 260 in 1992. Two gear sets and two propshafts in all those years, with big props and very high up.

And this stuff.

 

[ChrisV]

Oh man, I've used shockproof in our dogboxs transmission. I thought about using it in my sport master. This kinda confirms with me it works. I'm guessing you been using this stuff for awhile?

Anytime you change a part you have to check all the tolerances. In 30+ years of doing this I have learned ways to "cheat" around, But it still involves all the set up tools. I've made SEI cases with a nose cone live under a 300x on a bullet bass boat for years. There have been brand new Mercury Sportmasters I've had to tear down because the assembler spent the night at the cheese and beer bar and failed backlash 101. It's a lot of patience doing lowers and outdrives, and helps to have a dry ice supply around too.

Properly done a lower will last a long time. I still run the cle I bought under a new 260 in 1992. Two gear sets and two propshafts in all those years, with big props and very high up.

And this stuff.

 

[HST4ME]

It lasts considerably longer than Merc Hi Perf.

 

[Water Romper]

So I received the SEI 1 week after ordering it. The tracking and delivery updates were great, I knew exactly when it would arrive-I had to sign for it. The packaging was good, no damage whatso ever. The new lower came with the basic instructions especially the "Break In Process" why the long time line from delivery to install- I had to work.
It bolted right in place, everything lined up. Filled the lower with Merc. 90wt gear oil, hooked up the water muffs and turned it over- With some hesitation on my part... popped it in gear and the prop spun like a dream. Put it n reverse- same thing, prop spun great. Water came out the "pee" hole fine but it never came out that strong... (comparing it to other boats putting by) maybe its an inherent issue with this model and year but it seems to run cold enough.
I only ran it on the hose for maybe 5 minutes...

The following weekend we went to the lake and dropped it in the water and did the "maiden voyage" with the new lower. Not knowing what to expect, I popped it in gear and proceeded to chug along. slow, it felt a bit rough, almost a bit "grinding" but I knew the gears were new so away I went. The break in is between 3000 and 3500 hp for 5 hours, change lower oil, run at bursts of top speed (1 minute intervals for 10 hours) then it should be good to go. I have completed the 5 hours of painful 3000 rpm running, that hardly gets the boat on plane, but I stuck with the directions. I have replaced the "break in" gear lube/oil. Minimal shavings so that's good. So tomorrow- 4th of July, we will take her out again and get it up to speed....with a bit apprehension. New parts always make me nervous. Oh, and the grinding sensation seems to have gone away, I'm thinking with the new lower gear oil, that will make a difference as well. So whether your a fan of SEI or not, time will tell, so far so good but we all know- it aint shit unless we can go full throttle. The positive note is....if it scatters, it has the 3 year warranty. Bad news is- if it scatters, I could damage something else and even loose the prop.

Note the space for the anodes (crappy picture, it has the plastic wrapping over it)- thus the reason for the other thread.

 

[Flying_Lavey]

So I received the SEI 1 week after ordering it. The tracking and delivery updates were great, I knew exactly when it would arrive-I had to sign for it. The packaging was good, no damage whatso ever. The new lower came with the basic instructions especially the "Break In Process" why the long time line from delivery to install- I had to work.
It bolted right in place, everything lined up. Filled the lower with Merc. 90wt gear oil, hooked up the water muffs and turned it over- With some hesitation on my part... popped it in gear and the prop spun like a dream. Put it n reverse- same thing, prop spun great. Water came out the "pee" hole fine but it never came out that strong... (comparing it to other boats putting by) maybe its an inherent issue with this model and year but it seems to run cold enough.
I only ran it on the hose for maybe 5 minutes...

The following weekend we went to the lake and dropped it in the water and did the "maiden voyage" with the new lower. Not knowing what to expect, I popped it in gear and proceeded to chug along. slow, it felt a bit rough, almost a bit "grinding" but I knew the gears were new so away I went. The break in is between 3000 and 3500 hp for 5 hours, change lower oil, run at bursts of top speed (1 minute intervals for 10 hours) then it should be good to go. I have completed the 5 hours of painful 3000 rpm running, that hardly gets the boat on plane, but I stuck with the directions. I have replaced the "break in" gear lube/oil. Minimal shavings so that's good. So tomorrow- 4th of July, we will take her out again and get it up to speed....with a bit apprehension. New parts always make me nervous. Oh, and the grinding sensation seems to have gone away, I'm thinking with the new lower gear oil, that will make a difference as well. So whether your a fan of SEI or not, time will tell, so far so good but we all know- it aint shit unless we can go full throttle. The positive note is....if it scatters, it has the 3 year warranty. Bad news is- if it scatters, I could damage something else and even loose the prop.

Note the space for the anodes (crappy picture, it has the plastic wrapping over it)- thus the reason for the other thread. View attachment 1132545

Did you verify that your copper water tube has the gasket on the end of it? It may be stuck in the old water pump housing and thus not creating a good seal and allowing water flow to bypass out the exhaust.

 

[Water Romper]

Did you verify that your copper water tube has the gasket on the end of it? It may be stuck in the old water pump housing and thus not creating a good seal and allowing water flow to bypass out the exhaust.

I'm pretty sure i got the tube in correct. Maybe something "upstream" from the lower, i look in the engine compartment and can't see anything obvious, Maybe a blockage in the lines....as a side note, the water comes out the same when i had the previous lower on it.

Would the thermostat be the culprit? doesn't seem to run abnormally hot but I don't know what normal is.

 

[Duramax]

Anytime you change a part you have to check all the tolerances. In 30+ years of doing this I have learned ways to "cheat" around, But it still involves all the set up tools. I've made SEI cases with a nose cone live under a 300x on a bullet bass boat for years. There have been brand new Mercury Sportmasters I've had to tear down because the assembler spent the night at the cheese and beer bar and failed backlash 101. It's a lot of patience doing lowers and outdrives, and helps to have a dry ice supply around too.

Properly done a lower will last a long time. I still run the cle I bought under a new 260 in 1992. Two gear sets and two propshafts in all those years, with big props and very high up.

And this stuff.

Like @ChrisV said, this is the stuff to run? I run Merc but I will drain them this weekend if this is the best, which reading your post, sounds like it is.

 

[HST4ME]

Other than being expensive it's the best I've come across. The motors on my hydrostreams are way up there and I run 29-32 pitch props in the 7500-8k range. I think the gearset in my main lower is going on close 15 years old now

 

[Water Romper]

"29-32 pitch props in the 7500-8k range" I am glad to read this because mine runs about the same- 8000 rpm (when opened up and fully trimmed) it feels like it could even go more but I'm afraid of blowing the top of the motor out the cowling.

 

[ChrisV]

It lasts considerably longer than Merc Hi Perf.

How do you pour it in? haha

 

[Water Romper]

Well, coming up on the second stage of the break in- 10 hours at top speed for only a minute or two at a time then back off, wait a few then repeat.
Knowing this is an older (1992) Black Max 2 stroke- It rattles, shakes, knocks, smokes and vibrates. The "new" SEI lower seems ok, I get an odd vibration when making long sweeping right hand turns at above 35 MPH. When I straighten out, the motor/lower "smooths" out- vibration goes way. Possible pressure on the bearings due to torque on the prop shaft?
Anyway, have managed to get it at top speed, 8000 rpm, no real clue how fast I'm actually going but seems to run a bit slower than the previous lower prior to the break down- but it may be just me wishing i could get it faster. To be honest, the old boat is just getting tired. I run my Merc's hard, love going mid-range and then hammer down to get it up to speed, then back off. I love the feeling of being "sucked" into the seat. anyway, 2.5 years left on the warranty, good weather for the next few months so time will tell.

 

[STV_Keith]

I don't think a '92 150 fishing mota will turn 8k. You sure about that tach? Maybe 6k?

 

[HST4ME]

"29-32 pitch props in the 7500-8k range" I am glad to read this because mine runs about the same- 8000 rpm (when opened up and fully trimmed) it feels like it could even go more but I'm afraid of blowing the top of the motor out the cowling.

Your boat isn't going 115 mph.

 

[Water Romper]

The SEI saga- It been the second boating season on the "new" SEI lower unit and its starting to fail. I can "feel" the vibration and faint grinding of gears especially in a turn. I change the lower gear oil, very little shavings, minimal "milky" oil so that leads be to think the bearings are going out. Fortunately, SEI has an unconditional 3 year warranty so I will be sending this lower back for a new one. Because we still have a few more months of boating (Boise, ID) I am going to still run the boat but at low speeds just to be on the water. If the lower scatters, oh well.

So here is a call out to you lower unit experts:
I still have the original Merc lower unit, the bearings went out thus prompting the SEI purchase- Is there anyone out there that can rebuild my lower using (when possible) OEM Merc parts? Its a old 1991 smokey 2 stroke 150 Black Max. The lower is taken apart (by a local mechanic) so I would be sending what ever parts I have. It seems there are several Havi shops that may be able to take this on, not sure if there are folks in the Boise area, guys don't like these old motors.

What say you outboard gurus?

Thanks in advance.

 

[ChrisV]

Send the Oem to wide open throttle marine in vista California imo. Kyle is badass with that stuff

 

[Water Romper]

Send the Oem to wide open throttle marine in vista California imo. Kyle is badass with that stuff

Sent WOT an e-mail- Thanks for the tip!!