1986 Mercury 175hp Black max - RPM Question?

Lugnut · Post by **Lugnut** » Tue Jul 07, 2009 2:14 pm

1986 Mercury 175hp Black max - RPM Question?

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I posted this on iboats.com, but the more views the better.

I have a 1986 Mercury 175hp Black Max on my 1985 Ranger 370V. I currently have a High Five prop (I believe either 22 or 24 pitch, I know without the exact pitch it might be hard to answer the question. I will post once I have a chance to look). I was just wondering what the max rpm's I should be running on that motor? I typically run it about 5000rpm's / 50-52mph on my GPS. I have been reading guys that are running 65-70mph with the same year boat / motors. Sounds a little high, and I am sure they are running three blade props. not fives. My motor is older and I just don't want to run it to hard, if you know what I mean.

LEN B · Post by **LEN B** » Tue Jul 07, 2009 2:29 pm

5800 Should be the Max. As far as the 370V these guys should know.http://bbcboards.zeroforum.com/zeroforum?id=42

LEN

jimmy87 · Post by **jimmy87** » Tue Jul 07, 2009 4:44 pm

I have the same boat and motor. 60 MPH is about the max for me.

down current with wind to my back no passangers no water in wells and amlmost out of gas it runs about 65 or so.

never seen 70 MPH out of it.

5800 is maximun I run about 50 MPH 4800 or 5000 unless Iam in a big hurry.

Phil · Post by **Phil** » Tue Jul 07, 2009 5:21 pm

I HAVE A 300 SERIES 1989 WITH OLY A 150 EVINRUDE AND IT RUNS 58 0N GPS WITH THE WRONG PROP A 26 PITCH AND ONLY 5200 RPM........I WOULD THINK THE PROP IS WRONG FOR SURE.CALL PHILS PROP FOR CORRECT PROP, THEY GO WAY BACK TO THE 300 SERIES RANGERS AND KNOW WHAT OU WILL NEED .

JIGS