How to choose an old 2-stroke 150/175 Merc

Chris1956

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Maxrules does not show an XR6 with that serial number. A regular 150 or XR4 with that S/N is 1992. Does it have the smaller (4-1/4") diameter gearcase?
 

Dukedog

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So, 20" (long) shaft, small gearcase.
yep,, still original gear case is unusual for one that old.. thats a very good sign of how well it was taken care of!

here's another site will identify "what it is" jus not tha year... but crowley seems ta be better at both......


i had a pin number for tha merc site (ta get to tha parts) but is been to long ta be any good anymore!
 
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jimmbo

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Sooo... no nitrous injection? :ROFLMAO:
Nitrous would increase the Power(Torque) at any Rpm that is utilized at. But at Rpms above the Spec Range, the Port Timing will still restrict Induction, and the Power will still be Lower than what the Peak would be. Likely Melt the powerhead too...
 

BWR1953

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what hull ya gonna put it on?
If I'm able to buy the motor! :sneaky:

The seller informed me this morning that he has another buyer showing interest, but low-balled him. I told him that I'd definitely beat the offer if everything works out.

The Merc will get mounted on a 1997 Mirrocraft 18' aluminum fish n ski, which is rated for 150HP. I bought it in March, pulled and sold the old 85 Johnson off it and have been searching (off and on) for a 150HP Merc for the boat. This boat weighs the same as the current bass boat that the engine is sitting on.

This was the day I went for a test drive in the boat and ended up buying it and bringing it home.
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When I got it home.
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5.jpg


The one in the middle. I may end up starting a thread about the boat, but I'm being pulled in several directions right now. Lots of stuff going on here. 🤓
4.jpg
 

BWR1953

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Nitrous would increase the Power(Torque) at any Rpm that is utilized at. But at Rpms above the Spec Range, the Port Timing will still restrict Induction, and the Power will still be Lower than what the Peak would be. Likely Melt the powerhead too...
Yeah, it was a joke. :cool:
 

Dukedog

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Spinning it faster than the Recommended WOT Rpm Range, will result is a Horsepower Drop, unless the Port Timing, Induction and Exhaust are modified.
gotta disagree ta some extent.. if we didn't turn our motors (stock high production most rated at 8200 max) at 10 grand plus we might as well put it on tha trailer..... but thats "hot roddin".......:devilish:
 

BWR1953

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I made a 700 mile round trip and bought the XR6 boat. Seller let me start it and it runs great! The seller said the engine exhaust had been "drilled" and the carbs have larger jets. 🤷‍♂️

The whole overall deal was awesome. Nice guy, nice family, nice place, nice little town.


The trip home was uneventful and we're looking forward to getting the engine off the donor and moving on.
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Dukedog

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idle sound tells tha tale!.. sounds really good.. someone knew what they were doin' with tha removing tha can and where they drilled tha exhaust.. will go well on your tinny thinga ma jig......😎
 

jimmbo

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So the Exhaust now also comes out the Water Discharge Drains just above the AV Plate, which will also dump more water into the lower Exhaust Passage. Backyard Butchery
 

BWR1953

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idle sound tells tha tale!.. sounds really good.. someone knew what they were doin' with tha removing tha can and where they drilled tha exhaust.. will go well on your tinny thinga ma jig......😎
Thanks! Sounded awesome in person.

I don't know what removing the can and drilling the exhaust mean.
 

BWR1953

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So the Exhaust now also comes out the Water Discharge Drains just above the AV Plate, which will also dump more water into the lower Exhaust Passage. Backyard Butchery
Pretty negative comment. Backyard butchery? Can you explain?
 

Dukedog

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Pretty negative comment. Backyard butchery? Can you explain?
those are drilled holes in tha flat part of tha can (3/8" or 1/2", don't remember which one, five on each side) right above tha cav plate.. tha can liner is also pulled.... not back yard butchery.. drilled and/or cut anywhere else is butchery.. all hi performance "bass" cans are drilled there from merc production...... its tha only safe place ta do any exhaust drillin'.............
 
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Dukedog

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there is one downside to tha exhaust being that way besides tha noise and thats that your down housin' will discolor a bit more than normal from tha heat.. some say it will also effect tha water pump?.. never had that problem with any that were at least 20" motors.........
 

jimmbo

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Butchery, that is all it is. I doubt it even adds 1/10 mph
 

Dukedog

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louder means faster... jus ask any fisherman ('specially ina bass boat)...................... :devilish:

wouldn't call it butchery if its done in production.. but thats jus me.
 

BWR1953

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those are drilled holes in tha flat part of tha can (3/8" or 1/2", don't remember which one, five on each side) right above tha cav plate.. tha can liner is also pulled.... not back yard butchery.. drilled and/or cut anywhere else is butchery.. all hi performance "bass" cans are drilled there from merc production...... its tha only safe place ta do any exhaust drillin'.............
When you say can liner, do you mean the exhaust tube?
 
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