1984 Mercury 90hp 6 cyl

[bim213]

Anyone have any experience with this engine or similar? Looking at a 1983 v20 with one and want to know what to expect in terms of maintenance, fuel consumption, speed, etc. Thanks!

[RWilson2526]

Up until yesterday the smallest motor I've heard anyone talk about on here is a 115. then Robert644 (has the post about a hard top) says he has a 90 merc on his. I guess he'd be the one to answer your question. I know the couple of guys who have the 115 have commented it really isnt terrible but I dont know about a 90.

[macojoe]

Way to small, I don't see you even planing with that!!

[nipper]

I would be curious to hear what robert 644 says (even though he will have a lot more weight on his V), but I think it is under-powered. You could probably get it planing, but it would take a while. I had a 90 hp V4 Evinrude that pushed a 17 1/2 foot Speedliner like a scalded dog, but that boat was very light compared to a V20. If it is a nice boat you can always sell/swap the motor and get a bigger one. Most here think a 150 h.p. outboard is ideal.

[bim213]

Ok. Thanks for the replies. I went up to see it today and decided against it anyway. The boat is in decent shape but even the owner admitted the motor didn't really match the boat, which makes me wonder why he put it on there in the first place. Thanks again!

[randlemanboater]

Someone on here had that motor on a V and said it worked ok......top speed of 25 or so?

Who was it?

[turbinedoctor]

Someone on here had that motor on a V and said it worked ok......top speed of 25 or so?

Who was it?

That might have been me. I have an 84 center console with a 90hp inline 6 and it would do 25 - 30 mph depending on the load I had in it. I just rebuilt the engine and am still breaking it in. Now at 3500 rpms she will do 19 mph, cant wait to get the break in done so I can open it up again. Yes it planes just fine.

Turbinedoctor

[randlemanboater]

That might have been me. I have an 84 center console with a 90hp inline 6 and it would do 25 - 30 mph depending on the load I had in it. I just rebuilt the engine and am still breaking it in. Now at 3500 rpms she will do 19 mph, cant wait to get the break in done so I can open it up again. Yes it planes just fine.

Turbinedoctor


Yep.

[Destroyer]

I had that same Merc inline 6 engine on a Cruisers, Inc. 19 1/2 foot tri-hull. Strong engine that would get it up on plane and top off between 28-32 @ WOT. Sweet, strong motor.

Still... I had a V20 I/O with a merc 90hp 4 cyl that would not plane unless it was glass smooth. I really wouldn't have less than a 140 on a V20.

[eaj]

That might have been me. I have an 84 center console with a 90hp inline 6 and it would do 25 - 30 mph depending on the load I had in it. I just rebuilt the engine and am still breaking it in. Now at 3500 rpms she will do 19 mph, cant wait to get the break in done so I can open it up again. Yes it planes just fine.

Turbinedoctor
what size prop you running on the 90

[Steplift 72']

When I bought my 72 model V20 steplift, it had a 72 model 85 hp Johnson. Tried it out with that motor and immediately traded it for a 73 model 135 Johnson which ran great. I recall the 85 Johnson showed about 28 mph on an old airguide speedometer and you could throttle back a bit and still stay on plane. I really wanted to cruise at 28, not have that for full throttle. If I had a 90 that ran well, I'd use it. Keep in mind the older boats had saddle tanks that held just 40 gallons and the only equipment on mine was a compass and speedometer.

[eaj]

what size prop on the v 20 90