Joihnson V4 85hp Will rev but will not get on plane

[spybot]

I have a 1980 V4 85hp. I changed the impeller at the start of the season. Everything ran fine bar hard to select reverse.
I lived with it for a few months then had the chance to take the boat out of the water.
So i dropped the bottom leg. Adjusted the gear select rod to the correct height. When i put her in the water she would not get on plane. i thought it must be linkage or something like that. So i done a link and sync (even though i had touched nothing )
The engine revs to max rpm.
Throttle plate is horizontal plenty fuel getting but as soon as i go in to gear she wont pull.
I tied up to the jetty and put it in to forward and the boat hardly moved. it as if in a car and the clutch was slipping.
Please help if you can as im only at the boat till Friday night.
If i need to drop the leg again i will but what have i missed ?????

[RSWORDS]

So the motor turns rpm in gear but the boat doesn't move? Check the prop hub.

[flabum1017]

Is it going into gear and stays in at idle or slow speed? Is it clunking in and out of gear while trying to go or just feels like something is slipping when you try to go? If it feels like it's just slipping, it's possible the propeller hub has gone bad. If it's clunking, then the shift rod height and/or shift cable adjustments are wrong.

[flabum1017]

Is it going into reverse?

[FMP]

Did you find that prop you were looking for?

[phillnjack]

If in forward gear and the rpm is building up normal and it seems like its slipping then the propeller hub has gone.

Take the prop off and then mark the inner hub and the rubber and outer with a drop of paint or magic marker.
then put it back on and try again.
I have had this on props that look like brand new, with a mark on the hub it shows up big time.

I mark them on front and back, just so its easy for me to see straight away.
dont just do rubber and outer, as its the splined bit that could be slipping. .

[spybot]

Thanks I will give it a try report back in an hour or so

[spybot]

Update
I have changed props but no improvement
I took the boat out went to give it throttle but the same thing happens the boat is trying to rev but something is holding it back. When i was motoring in full throttle it seems like it was trying to clear its self like a daa --- daa --- daa it kept on doing this but didnt get any better still cant get on plane even at full throttle. will take the lower unit of tomorrow and hopefully set the gear selector rod to the correct height. She struggles to get in to reverse ( just does the grinding noise but won't go in gear) I thought i had the correct height but seems not. Is there anything else i can do to correct this issue ???
To sum up.
The engine was sitting to high on the transom. So i lowered it to where it was when i got the boat.
I adjusted the gear select rod to the correct height ( well what i thought was the correct height)
Then put on the original prop
Thats all i have done so the problem lies in one of the above
Hopefully tomorrow i will find the cause.

[flabum1017]

Check the oil for metal

[phillnjack]

so the engine is not revving up ?
your not getting the revs to 5,000 plus, you have a problem with the fuel or the timing..

you might "THINK" you have it all set right but obviously not if its not revving up.

have you checked for spark jumping a 7/16th gap on every cylinder . just sparking on the plug dont mean much, you need to know its
capable of jumping the distance and be a nice sharp blue spark.

are you sure when its in gear that the throttle is opening the carb up to the max ?
is the choke closing correctly ?

what plugs are you using and what gap ?

try starting it up and night on the trailer in the dark and see if any wires are sparking .

[flabum1017]

so the engine is not revving up ?
your not getting the revs to 5,00 plus, you have a problem with the fuel or the timing..

you might "THINK" you have it all set right but obviously not if its not revving up.

have you checked for spark jumping a 7/16th gap on every cylinder . just sparking on the plug dont mean much, you need to know its
capable of jumping the distance and be a nice sharp blue spark.

are you sure when its in gear that the throttle is opening the carb up to the max ?
is the choke closing correctly ?

what plugs are you using and what gap ?

try starting it up and night on the trailer in the dark and see if any wires are sparking .

Now I'm confused, his first post, he said it revs to 5000 rpm and seems like it slips like a car with a bad transmission, now he's aying it won't rev???????? :confused:

[phillnjack]

ok so lets start with the gearcase.
take it off again and re-measure the length, make sure your measuring from the top surface of the gearcase edge to centre of bolt hole !!!

now when you put the gearbox back up make sure it slips into the splines !!! if it dont go all the way up easy its not going into the splines.

now forget about what it was like originaly. , its easy to adjust the cable for gear change.
put the gear lever on the box into the middle ( neutral) . before connecting the cable to the motor push the lever on engine into reverse and turn the flywheel at same time by hand ( no ignition key in switch or could start and rip your hand off).
the rod should go in fairly easy if your turning the flywheel at same time.
make sure you only turn flywheel clockwise and then look at propeller to see if its reversing or going forward.
once its in reverse then put remote into reverse and then see if cable needs adjusting, it should be exact right and not slightly less if you get my drift.

Now when you originally dropped the gearcase did you take off the small alloy fitting that connects the shift shaft to the motor ?
is it the right way up ? it should be with the bolt facing downwards, not upwards.
(you dont even have to touch the bolt once you know the easy way to disconnect).

if any of these things are wrong it could make it hard to go into forward or reverse gear nice and smooth.

once engine is in gear the gearcase will not be slowing you down, unless its seizing up, that is not your problem.

the lync and sync has nothing to do with the throttle cable or gearshift, that is timing and throttle plates etc.

I have sent a pm about easy way to drop the leg.

[spybot]

Cheers Phill will do when I go to take the unit off.
The problem I had was the wrong mix. I had fuel from my mate he was running 50/1 I have to run 25/1 due to the seals being perished. She will only run on a thick mix