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The Outboard Church

patina

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So back to some technical talk. The Promax has a Sportmaster lower unit. The previous owner told me he had the lower unit would occasionally drip a few drops of fluid when parked but at other times would not. I have now experienced this for myself after moving the boat around my shop a few times. At first it didn't drip a drop, then after I moved it again and fumbled with it it left about a quarter sized drip on the floor below the skeg that appeared to be coming out of the prop shaft area. According to the previous owner, the lower unit on the boat has been off/apart several times to remedy this. The prop shaft was taken to machinist who said it must have had fishing line caught up in it at some point which slightly marred the surface. The previous owner told me it did not let water in and that he just kept an eye on the fluid level (he said he had to add approx 1/4 quart per season). This kind of seems like it may not be 100% the truth but I took him for his word.

Regardless, I just talked to Don at European Marine in Greenville, SC (he knows these engines/lowers) and he kind of scared me. He basically said there's no way it's letting fluid out and not letting water in and that the parts to rebuild/etc. are NLA. Is this true? He recommended running Quicksilver High Performance lube and keeping a close on eye the level/water intrusion. He basically made it seem like this lower unit was a ticking time bomb.

I’ll be dropping the fluid this weekend to see what it looks like.
 
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sonicss31

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It’s not a matter if it will but a question of when. BTDT. Find a reliable/reputable shop to fix it ASAP. It will save you money to do it before it fails.
 

HST4ME

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Parts are not NLA except for the "small" prop shaft, which were prone to breaking at the spin weld after fatiguing. They will normally burp out the shift shaft seal when overfilled and/or after some serious usage. Which is easy solved with a small expansion tank kit. You can PM me if you want to discuss some things.

I've been using Rev X or Redline oils for a several years now and they are leaps ahead of anything mercury offers.
 

lake p.a.l.

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Be very careful in the turns, it will react much differently in each turn right & left depending how much weight you have in it
 

n2otoofast4u

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It does not.

I am a huge fan of them. I always drill a VERY small hole in the top of the reservoir as well, then cover with a cloth. If shit it’s the fan, you’ll see it leaking oil before it totally eats itself. In my eyes, the most difficult thing about the OBs is keeping the gearcases together.
 

War Canoe

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I am a huge fan of them. I always drill a VERY small hole in the top of the reservoir as well, then cover with a cloth. If shit it’s the fan, you’ll see it leaking oil before it totally eats itself. In my eyes, the most difficult thing about the OBs is keeping the gearcases together.
Joe Abellera said to change gear oil after every hard run. Cheap insurance! Easy to do.
 

ChrisV

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Parts are not NLA except for the "small" prop shaft, which were prone to breaking at the spin weld after fatiguing. They will normally burp out the shift shaft seal when overfilled and/or after some serious usage. Which is easy solved with a small expansion tank kit. You can PM me if you want to discuss some things.

I've been using Rev X or Redline oils for a several years now and they are leaps ahead of anything mercury offers.
I’ve been telling myself to use the redline stuff cause I’m a dealer. Lightweight shockproof?
 

HST4ME

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I’ve been telling myself to use the redline stuff cause I’m a dealer. Lightweight shockproof?
either light or heavy is fine. I use the heavy as most of my running is long miles. My tip to Tennessee was probably 1000 miles over a week. I checked it a couple times in the hotel parking lot and ran the rest of the summer on it. The water dumps from my exhaust plate are run with tubes that point to the bearing carrier which helps bunches, motors like the 3 liter mercs are much harder on gear lube due to the plumbing and especially the optis with the egts they run.
 

n2otoofast4u

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Joe Abellera said to change gear oil after every hard run. Cheap insurance! Easy to do.
Yep! 5gal bucket and 20mins. I changed mine after every rip. Use on Saturday, change on Sunday morning before heading back to River!
 

HST4ME

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REV X DRIVE-H 80W90 Marine Outdrive Gear Lube – 5 gal $679.00​


I try to milk it out on my personal stuff.. for reasons, lol. Customers I'll change it as often as they want.
 

Markus

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Joe Abellera said to change gear oil after every hard run. Cheap insurance! Easy to do.
Steckbauer said every 5 hours. “Not because the oil needs changing, but because you will see what is going on”
 

patina

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Going to drop the gear oil and take a look. If it's milky this lower unit will be headed to Michigan. I'm already very grateful for you all!
 

HST4ME

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We're trying to avoid this, it was a good time getting that pinion nut off.

1706394730369.jpeg
 

patina

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Well... as we all speculated the lower unit is taking on water. I'm pretty disappointed in the seller for lying straight to my face (specifically said he's never seen water in the gear oil) but it is what it is at this point. I'll be packing it up and sending it to @HST4ME this week for some surgery! Just lucky to have found this now vs. blowing it up in the middle of the lake.

Another question for the group - the lower unit had an Allison cavitation plate installed - what's everyone's take on keeping that vs ditching it?

IMG_0494.JPG IMG_0497 2.JPG
 

ChrisV

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Well... as we all speculated the lower unit is taking on water. I'm pretty disappointed in the seller for lying straight to my face (specifically said he's never seen water in the gear oil) but it is what it is at this point. I'll be packing it up and sending it to @HST4ME this week for some surgery! Just lucky to have found this now vs. blowing it up in the middle of the lake.

Another question for the group - the lower unit had an Allison cavitation plate installed - what's everyone's take on keeping that vs ditching it?

View attachment 1327845 View attachment 1327846
I recomend buying another lower unit. Drives seems to be the problems in boats general.
 

stoker2001

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Another question for the group - the lower unit had an Allison cavitation plate installed - what's everyone's take on keeping that vs ditching it?

View attachment 1327845 View attachment 1327846 every setup is different,but pros are it will help reduce planing time and help keep boat on plane at slower speeds ussing full negative trim.they do put added stress on your cavitation plate and could cause failures/cracks..?
 

patina

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Markus

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Didn't you have a 2.5 liter engine? It is the 3 liter Sportmaster that needs the Wayne Taylor double seal holder.
 
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