1987 yamaha 40 hp

[7173george]

I am thinking about buying a 1987 40 hp. that was converted to a jet. price is 1500. does anyone know any thing about this year motor? are they reliable.this motor has not been run in years. what should a compression check read? 3 cylinder .

 

[99yam40]

Re: 1987 yamaha 40 hp

25 year old motor that has not run in years, and no idea how many hours on motor or jet, I would not buy it unless you could run it hard on a boat close to what you plan on putting it on to see if it will perform like you would want and it has no problems.
You do realize it will have the power of about 28 HP with the jet. $1500 sounds high to me but never priced a jet

 

[mphelle8vld]

Re: 1987 yamaha 40 hp

+1 to everything above, if it's a freshwater motor that was properly fogged before storage, with 125psi in all cylinders and clean carbs, it could be a good buy at that price. Given your river you certainly need a jet, and that motor with your payload would perform just "OK". What's the max hp for your 1448 and is it tiller or remote steer?

 

[7173george]

Re: 1987 yamaha 40 hp

my boat is remote steer and max hp. is 60.

 

[1080tommy1]

Re: 1987 yamaha 40 hp

This past February I bought a 99 Yamaha 40 hp that was in pretty good condition for 1400. I do not know if it is worth more because of jet conversion but to me for that year seems high in $$$$. The engine I got was running but definitely needed some TLC. I cleaned all three carbs and she runs like a top. Her internals were great though and I would make sure you have at least 120psi in each cylinder and see how she runs. The motor I bought was fogged and the lowere unit oil was like new so I am pretty sure they took reasonable care of it however the carbs were not functioning well. Main needle in lower carb was totally frozen and that was on a 99 that only sat from September to February. If you need to do that work, I think the price should come down. I love my engine and it was well worth the 1400 and if this one is like mine, it will perform great. Hope it works out for you. I would definitely compression test the motor before making any decisions.

 

[mphelle8vld]

Re: 1987 yamaha 40 hp

While you're thinking about it, the general rule with jets is 25lb of payload for every 1 of powerhead hp so you would be at 1000lb. In a previous post I believe you thought you had a load of 1200lb so it might be a little slow to get on plane. It might be enough power for your needs and would certainly let you know if a jet is your cup of tea, but I would still keep my eye out for a 60/40 two stroke. Let me know the make and model number of your boat, if it's a 1448 w/60hp max, I think I need one.

 

[7173george]

Re: 1987 yamaha 40 hp

my boat is a 2011. it was rated at 25 hp. max. I filled out a form, and sent it into the fish&boat comm. with all the measurements they asked for. they sent me a new cap. plate and now it's rated for a 60 hp. max.I'm going to liten up the load in my boat and hopefully a 40/30 would move it around the river pretty well.

 

[99yam40]

Re: 1987 yamaha 40 hp

Getting a boat re rated from a 25 to a 60 just by filling out a form is a new one to me.
Did you have to beef up the transom or just fudge the info some

 

[7173george]

Re: 1987 yamaha 40 hp

just sent in the exact measure ments they asked for on the form.On the form there is a scetch of a a boat showing where to measure, sent in the form and got a new cap. plate. I didn't fudge any numbers.

 

[99yam40]

Re: 1987 yamaha 40 hp

I always though HP rating had to do with the transom being able to handle the strain, probably would not be the 1st time or the last time I was wrong tho

 

[7173george]

Re: 1987 yamaha 40 hp

Well, I did not buy the 1987 40/30 jet.The motor looked great, had 120 psi in all 3 cylinders. the problem, no spark. The guy selling the motor had a battery hooked to the motor but it was a pull start. why would you need a battery if it's a pull start? I think he had no clue but neither do I.I think the kill switch was broken off and the two wires were where he thought a battery should be hooked up.

 

[mphelle8vld]

Re: 1987 yamaha 40 hp

The factory 40/28 had only pull start, but since his was converted from a prop it may well have had electric start also. I have an 88 that has both. Since he appears clueless and the motor does not run, you could offer him a grand and start troubleshooting.

 

[7173george]

Re: 1987 yamaha 40 hp

Went back and bought it for 500. it is only pull start. Now where do i begin to start trouble shooting the no spark issue?

 

[mphelle8vld]

Re: 1987 yamaha 40 hp

Good buy, Post as many clear photos as you can. Figure out why the battery cables are in there. Check the fuse inside the cdi cover. Repair the kill switch issue. Let us know what you find as you go but don't start the motor without using pre-mix, you want to double up on the oil while you bring it back into service.

Also post model number on transom clamp, remote or tiller, and even more photos

 

[7173george]

Re: 1987 yamaha 40 hp

Numbers on the tag are 40 SHJD. it is remote steer.There are no battery cables.he was hooking the battery to 2 thin wires that , i think were wires for a kill switch, but i'm not sure.DO YOU NEED A BATTERY IF IT IS ONLY PULL START? I wouldn't think so, if they were for a battery thet would be heavy gage wire. antway I hope you guys can help me figure it out. jet motors here go for big money , if i have to put a few hundred into it, it will be well worth the investment.

 

[mphelle8vld]

Re: 1987 yamaha 40 hp

NO!

 

[99yam40]

Re: 1987 yamaha 40 hp

40 SHJD means it was factory jet
Not sure about that old of motor, but all I have delt with the kill switch grounded the CDI out put to keep coils and plugs from sparking. So hooking up battery to them does not sound good for electronics if that is where they ran to. My C40 TLRX CDI cost me $400, but you need to test input and outputs to see what is going on.
A Yamaha service manual will give all info for testing and equipment needed. Pick one up and read or do a lot of searching online to find the info you are needing

No manual start motor needs a battery to run

 

[7173george]

Re: 1987 yamaha 40 hp

THANKS! I just came in from my garage. He probly cooked something then.I will search for a service manual.can the cdi box be tested.

 

[7173george]

Re: 1987 yamaha 40 hp

I wounder if it is a1987?

 

[99yam40]

Re: 1987 yamaha 40 hp

There is a 40 SH-JD listed for 87 in parts.
Not sure about testing CDI but If the input voltages are good and out puts are not that should tell you