'68 65hp Johnson V4, stalling after 100 yds, smoke

[Geodopolis]

Used to die at throttle, cleaned carbs, checked impeller, new fuel lines. Took it out for 2nd maiden voyage today, glad I had a trolling motor thrown on! Made it away from the dock, opened her up and never got on plane(trim adjustment I hope). After about 100 yrds motor sputtered and died. Produced quite a bit of smoke while running. Tried to restart and wouldn't turn over(brand new battery). after 1/2 hour sqeezed the bulb for a restart and fuel squirted out the top of the carbs. gave it about 15 mins and restarted with no prime perfectly. quit after 50 yrds. Could it be overheating? Used the trolling motor the rest of the day. When I got it back onto trailer, I noticed some grey sludge coming from one of the bolts holding the lower unit on (quite a bit of it). Someone save me from me.

 

[sheboyganjohn]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

Sounds to me you have a few issues going on.

First, squeezing the bulb and fuel coming out of the carbs sounds like your float is not adjusted correctly or you have something caught in the seat. you should not be able to pump the bulb and have fuel come out of the carb.

Second, not being able to turn over is not a good thing. It either overheated or hydrolocked. If it was smoking a lot of white smoke, then it might be leaking water into a cylinder. If it was a lot of blue smoke, then you may have too much fuel (most likely due to the above carb comment). I do not know if it is possible to run so rich that you hydrolock with fuel, but it might be possible. Look at the heads, if the paint is peeling, then you overheated.

Not being able to get up on plane, if the carb is leaking past, you are running too rich which will bog down the motor.

Last, the sludge leaking from the lower unit bolts might be a mix of fuel/oil and water, but I am not sure from your description where exactly it is leaking from. A picture might help with this one. Remote chance it could be the lower unit leaking.

 

[Geodopolis]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

OK, finally had time to work on the motor again. Adjusted the float and now the bulb gets firm without fuel squirting out of the carb. As for overheating, I didn't see any peeling paint, but I'm concerned about the water pump. Where is the water supposed to exit the motor? I put it in a barrel of water and started (perfectly) I couldn't see any water leaving the motor. I did see what appeared to be exhaust (white smoke) bubbling from the screen directly above the prop on the underside of the horozontal fin. I think that's where some sludge was coming from before as well. I don't have any pic's, I'm about as low-tech as you can get. Is there seals/sealant I should use when putting the LU/impeller back together? Thank you in advance for any more help.

 

[sheboyganjohn]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

I am not familiar with the older V4's, but if you go to the shop.evinrude site, you can find a parts breakdown for your motor, they also have the Johnson motors listed there.

As for the water exit, I will have to defer to the experts on the site. usually there is a relief hole on the back of the middle section that will have some exhaust with a mist of water in it, but then again, I do not know the design of your motor. If you have not done the water pump impellor, it is most likely over due and you should change it.

 

[film495]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

i've seen people mistake steam for smoke when overheating. this is cause to immediately turn the motor off. running on muffs, you should see water spit out of the holes in the back of the motor I think, if it doesn't do that your water pump is suspect.

 

[jtexas]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

A compression test will indicate whether it overheated to the point of damaging something. Also whether your head gasket is blown.

What do the spark plugs look like after idling? wet? dry? fouled? clean (like they've been in a steam bath)? Insulator should be tan to golden brown, if it's white, you're overheating.

Your water intake is above the prop on the aft portion of the antiventilation plate, so you can't use regular "muffs" to run the motor out of the water. I've seen garden hose attachments for that type of intake, though.

I don't think you have a telltale. The exhaust relief ports on back of the motor, you won't necessarily see water coming out there if the lower unit's not submerged.

The water pump has a housing gasket, also a water tube guide with a washer and grommet. If the housing is at all scored, it should be replaced.

Sounds to me like the "sludge" is dripping from the exhaust -- go to the Engine FAQ section of iboats, read the thread on "decarb".

 

[Geodopolis]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

Been busy fishing lately, I figured out that the impeller key was MIA and fixed that, also, the grey sludge disapeared. It was coming out of a tiny drain hole that another post said is common to leak out unburnt 2cycle oil. Now just have to figure out how to make it faster/plane/power.(see newer post) Thank you for all your help guys

 

[tashasdaddy]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

on that motor you need to have the leg submerged in water atleast 1/2 way up the leg, for it to pick up water correctly. sounds to me you need to do a link n sinc. have you checked compression and spark? timing?

 

[joshbierly]

Re: '68 65hp Johnson V4, stalling after 100 yds, smoke

I had the plain issue with my 64 evinrude and had to switch to a smaller pitch the boat was to heavy and the motor had lost to much power over the years to use the 12pitch that was on it. I had to go to a 10.5pitch for mine.
I have a couple of props I don't use a 11 and a 12 pitch if yours is larger and you are still having the problem. josh-scouts@live.com

Josh