Johnson J8RCTA 7.5hp?

[1946Zephyr]

Yea, I thought this was kinda odd.

I decided to put my old JW-14 in the paper to sell and a nice older fella down at the coast answered and offered to trade me the motor listed on the headline as a trade. Being the nice honest guy I am, I told him that his motor was most likely worth twice as much as mine and he should sell his and then buy mine. That way he would have as much in his pocket as he would have paid for mine. Well he called me back a little while later and told me that if I was willing to make a 2 hour drive down to the coast, that he still wanted to trade me straight across for my 52 year old J-Dubb.
I guess he must have made some calls and someone told him that the old J-Dubbs were great motors.

So, now I have this nice little Johnson 7.5 sitting in the back of my car. The thing I think is odd, is that I thought the last 7.5hp was built in 1958 with the Holiday Bronze finish. This motor I have is just like the modern day 9.9's and 15's, but I thought the only thing we have next down is the 8hp.

My guess is, this motor was built to be sold offshore, eventhough the id tag says it was built in Illinoise. The model number says it's a 1983. The ol' boy I got it from says it's a 1982. So, what can you guys tell me about it? I know I've seen a lot of forum members here with motors built in Belgium, Canada, Australia, and god knows where.

The one in the picture is not the one I have, but mine is just like it.

This link will have more pics of it. http://www.boats.com/engines/engine...81%2b4294957329&et=100&N=1783+781+4294957329&

 

[tashasdaddy]

Re: Johnson J8RCTA 7.5hp?

checks out as a 1983 7.5 on the BRP parts diagrams.

 

[Vic.S]

Re: Johnson J8RCTA 7.5hp?

But for the decals and the paint colour it would be difficult to tell it apart from my 1984 6hp Evinrude.

Things that may cause you trouble

The grommet at the top of the water tube. Corrosion round it squeezes it over the top of the tube until it cuts off the water flow.

The carrying handle. Its plastic and may break!

The way in which the prop is pinned to the shaft. The pin is under the plastic cone not in the "back" of the prop and it only passes through a light brass insert in the hub. The brass (?) insert on mine has failed and I have had to drill another pair of holes.

Apart from the flimsy carrying handle the other problems may not be problems in fresh water.

 

[1946Zephyr]

Re: Johnson J8RCTA 7.5hp?

But for the decals and the paint colour it would be difficult to tell it apart from my 1984 6hp Evinrude.

Things that may cause you trouble

The grommet at the top of the water tube. Corrosion round it squeezes it over the top of the tube until it cuts off the water flow.

The carrying handle. Its plastic and may break!

The way in which the prop is pinned to the shaft. The pin is under the plastic cone not in the "back" of the prop and it only passes through a light brass insert in the hub. The brass (?) insert on mine has failed and I have had to drill another pair of holes.

Apart from the flimsy carrying handle the other problems may not be problems in fresh water.

Yea, the prop set up is like that of the older 5.5 and 7.5 of the 50's. Well, for a motor of this cailibur, I don't see much of a problem there. I see what you mean about the carry handle. Luckily it isn't broke yet.
I hooked up a fuel tank to it today and it fired right up. I found that the previous owner gapped the plugs out to about .050 or bigger and I thought that was odd. So I regapped them to .030. I took a compression test and both cylinders came out to 80psi each. Not bad for a motor with as small of pistons as this one has. It runs great and runs smooth. I'm going to change out the impeller and lower unit oil and call it good. I also need to go into the tiller handle, because the throttle doesn't work with it. It was set up for remote controls and the tiller handle seems to be disabled.

Update: Tonight I changed the lower unit oil and no sign of water intrusion. Woohoo!! So far things are looking good with this motor.

 

[redfishsc]

Re: Johnson J8RCTA 7.5hp?

But for the decals and the paint colour it would be difficult to tell it apart from my 1984 6hp Evinrude.

Things that may cause you trouble

The grommet at the top of the water tube. Corrosion round it squeezes it over the top of the tube until it cuts off the water flow.

The carrying handle. Its plastic and may break!

The way in which the prop is pinned to the shaft. The pin is under the plastic cone not in the "back" of the prop and it only passes through a light brass insert in the hub. The brass (?) insert on mine has failed and I have had to drill another pair of holes.

Apart from the flimsy carrying handle the other problems may not be problems in fresh water.

Vic, I have this exact same motor and you just answered a huge question for me. I know this is an old thread but I hope you or someone else can answer a further question.

I had a waterflow blockage and found exactly what you just said. The grommet at the top was squeezed entirely shut and it baffled me. There was a good bit of corrosion around it and I suppose it had squeezed it shut.


Anyhow, I cannot find a round grommet that seems to match. Everywhere I look, it's either "obsolete" or it's listed as fitting only the 4.5hp and it's a U-shape instead of a round O grommet.


I will try sending you a PM, hopefully you will see this or get the PM. I need to try to find a new one or figure out how to make a "DIY" version.