Black Max 175 info

[DamianJP]

Hi I have a Black Max 150 XR-4 (OB289510) and wanted to know if parts (LowerUnit most importantly, But some other's aswell) from a Mercury Black Max 175 (OB242147) non-XR series fit the 150. Info so what Ratio would the L/U on the 175 be? Seloc had only 3 listings for the 175 and the one in the 85-88 year range said 2:1. Iv'e seen people posting that 1.87:1 was a better for that motor and a bass boat. Mabey some one could shed some light on the diffrent L/U Ratio's.

Thanks,
Damian

 

[jsd1204]

Re: Black Max 175 info

My Mercury Service manual says it is a 1.87:1 lower unit on a 175. I hadn't heard whether the 2:1 or 1.87 gear ratio was better. I am interested in the response as I also have a 150xr4 with a lower unit problem. Hope that helps. Jason.

 

[j_martin]

Re: Black Max 175 info

The XR4 comes with a 4 inch lower, at 1.78 gear ratio. You can put a 4 1/2 lower on it, but I don't think many other parts, including props interchange.

I own one, and I love it. It's a slippery little bugger. In good tune and with the best lube in it, it gives good service. Abuse it, and it'll put a pinion out the side in a heartbeat.

hope it helps
John

 

[DamianJP]

Re: Black Max 175 info

Thank you Jason, didn't know it was 1.87:1 I know seloc was wrong when I went to change my jets out. BTW what do you have your 150 on and whats up with it?

And thanks again John. I remembering you helping me out a fuel related problem awhile back. Also have you pulled out the boat yet?

Also is the 87 Mercury 175 Black max non XR have any interchangeable parts with my 89 150 XR4?

 

[jsd1204]

Re: Black Max 175 info

I have a 1988 Ranger 374v with a 1988 150 xr4. I bought the boat used last fall. I had it out a total of about 2 full days when, while running about 30 mph I got too shallow and hit something(I think a stump). The boat went into nuetral and wouldn't go into gear again. The lower unit housing is intact other than a couple nicks/scratches. One SS blade was a little bent. It started right back up but would not go into gear(or make any noise while shifting). It is in the shop right now. Hopefully State Farm will repair. Playing the waiting game until shop/adjuster calls.
Sorry, got off track. My repair manual doesn't list any interchangeable parts, but check other forums. This seems to be the place to find out anything about boats. Love this site. Jason.

 

[j_martin]

Re: Black Max 175 info

Thank you Jason, didn't know it was 1.87:1 I know seloc was wrong when I went to change my jets out. BTW what do you have your 150 on and whats up with it?

And thanks again John. I remembering you helping me out a fuel related problem awhile back. Also have you pulled out the boat yet?

Also is the 87 Mercury 175 Black max non XR have any interchangeable parts with my 89 150 XR4?

Probably a lot of them. There are a lot of variations. The peripheral stuff, fuel pump, starter, flywheels, etc all interchange. Reeds probably interchange, carbs also with adjustments.

The XR4 is pretty snappy right out of the box. You can shave the heads and run 92 octane in it and get another 10 0r so out of it, which puts it near 175 at the prop. After that, yer better off selling it and buying a bigger motor.

If you wanna go nuts with the die grinder and money is of no consequence, I've heard of some pretty scary running engines built up on that block.

The big difference in the XR4 is the smaller, higher geared LU. It was marketed as a hot 150 horse bass bote motor.

By bote's in sorry shape. Motor's on a stand, cables and electrics scattered all over. Transom is cut out. Looking for some time to cut out the floor and deal with the wet stringers. Then I can glue in a fresh transom and put it back together.

Hope to get it back together by the end of the month.


hope it helps
John