Merc 500 vs. Johnson 85

[64osby]

I am looking at upgrading to the 1970's.

I have a 1967 Merc 500 50hp on a 1964 17' Crosby fish n ski. We use it for tubing and knee boarding. Boat and motor are in great condition and I have never had an issue with the motor (knock on wood). I know it is slow out of the hole. I am looking to get my kids skiing this summer and am considering a change. I have never skied behind this boat, I know it will pull my kids up ok, the are under 100lbs. I don't think it is up for the task of pulling an adult out of the water quickly. It's been 20 years since I've skied but I know my kids will want me to show them first. Where's the video cam.

The boat I'm looking at is a 1970's Aero Marine Javelin 16' to 17' with a 1975 Johnson 85hp. The boats in good condition, the guy says the motor runs great at high speed but "needs the carbs balanced" for it to idle good. The boat is also open bow which is appealing.

Money aside, I can sell my boat for more than the new purchase.
Aero Glass weighs less than the Crosby
Newer trailer is nicer than my gator
Aero Glass is in good shape great gel coat, new sump pump, new power trim, needs upholstery in the bow and i can do that, new impeller and housing on Johnson

My questions are

Will 35 more HP be a noticable difference when trying to ski, and get out of the hole?

Does the Johnson have a good history related to repairs, or lack of?

I,ve read the sticky on tuning the Johnson carbs and feel I can do it. The seller says it has to be done by a tech with a meter,???

I love my Merc and would not want to make a change for the worse

Any input would be great, thanks in advance.

I know I'm asking lots of Johnson questions on a Merc forum but If I ask them on the Johnson forum I think they will tell me the Johnson's are the best

 

[coolguy147]

Re: Merc 500 vs. Johnson 85

you don't need a meter for that motor to idle

compression
spark
gear oil
overall condition


test run!!!!!!!!!!!!

soft spots
transom check

if purchase replace the water pump and impeller (just do it).

pictures?

 

[64osby]

Re: Merc 500 vs. Johnson 85

coolguy I did not think it required a meter to adj carbs, but thought I'd ask anyway.

Pictures of the Aero Glass Below, I don't have any of our boat on this computer will upload later.

I took a short look at this Aero a few days ago, and was asking a few questions before I go back to take a hard look.

compression NEED TO CHECK
spark NEED TO CHECK
gear oil NEED TO CHECK
overall condition UPHOLSTERY in BOW POOR all else GOOD other notes on my original post, boat is missing center window, speedo pick up pressure, style, Prop needs to be reconditioned,
test run!!!!!!!!!!!! NOT YET
soft spots NONE
transom check GOOD

I'm just trying to figure out if the Johnson has a good rep and if 35 additional HP is worth chasing.

The fine tooth comes on the next visit.

 

[64osby]

Re: Merc 500 vs. Johnson 85

Well I went an took a hard look at the boat. Needless to say it's not coming home, today or ever.

The transom is shot has a 1 1/2" bow in it and the glass is cracked were it turns to horizontal. Needs a lot of other little stuff. If I didn't have so many other projects at this time I might consider. 85 horse Johnson, Gator Galv trailer and the boat. The guy was willing to take $500.00 but it would be a lot of work to get it safe.

The transom moved so much it looked like the motor would fall off at any time.

I'll keep looking.

 

[coolguy147]

Re: Merc 500 vs. Johnson 85

hahahaha lol " it moved so much i thought the motor would fall off at anytime."

my dad used to ski behind a 14foot 6 inch fiberglass boat with a 1961 mercury 500. light boat though.

 

[64osby]

Re: Merc 500 vs. Johnson 85

The first boat I skied behind was a 14' Alum w/ a 15 hp. We used to have the boat even with the skier, go WOT and watch the rope peel out, get a huge pop on the arms, then drag for while, and finally pull yourself out of the water. Then you waited for the boat to pick up more speed before you would drop a ski.

Oh to be 15 years old again

 

[trendsetter240]

Re: Merc 500 vs. Johnson 85

Well I went an took a hard look at the boat. Needless to say it's not coming home, today or ever.

The transom is shot has a 1 1/2" bow in it and the glass is cracked were it turns to horizontal. Needs a lot of other little stuff. If I didn't have so many other projects at this time I might consider. 85 horse Johnson, Gator Galv trailer and the boat. The guy was willing to take $500.00 but it would be a lot of work to get it safe.

The transom moved so much it looked like the motor would fall off at any time.

I'll keep looking.

Why not make him an offer on the motor if it's in good shape? Then mount it on your current boat in place of the 50.

Yes, 35 more HP will make a world of difference on a 17ft boat. I went from a 50hp to 70hp on my 17ft and it's like night and day.

Plus, the 85 is a V block and will have way more torque than the merc 500.

If you do go for the motor, make sure it comes with the controls as your merc controls aren't compatible.

Cheers

 

[64osby]

Re: Merc 500 vs. Johnson 85

Trendsetter
I considered, but the control cables are too short for my boat. I would spend more on new control cables then the motor. I still consider offering about $300 for it all and throw the boat away.

 

[Topol_86]

Re: Merc 500 vs. Johnson 85

Before giving up on the idea of getting the boat because of the transom, give THIS THREAD a read through. Its a guide to rebuilding the transom using sea-cast. Just my $0.02

 

[64osby]

Re: Merc 500 vs. Johnson 85

Topal
I have read that seacast post before. Looks like great stuff.

I'm kinda looking to upgrade if it's easy and just tinkering.

I have too many projects now.

 

[Topol_86]

Re: Merc 500 vs. Johnson 85

Understandable. From my experience/knowledge most people write off a boat because of a weak transom from not knowing of seacast, thought i'd offer up a solution though. Either way, Happy boating