1970 Johnson 60 HP 3 Cyl. won't stay running.

[domwebhost]

Hi,

To those that are veterans to this forum you already know that I have a 1970 Johnson 60 Hp 3 cyl. (with wire terminal and monkey nutz). I finally took the boat out on the water today. I tried to start it and it would turn over and run VERY rough for anywhere from 5-20 sec. after which it would die and I would have to hit the key again to get it to fire again. It did NOT run everytime. Sometimes it would fire (and then I would hear the starter spin) and other times it would stay running for a few seconds. Things that I have done to the engine so far include: new plugs and plug wires, new coil, new gas lines ( between carbs) and new gas line (primer bulb assembly) I took off the flywheel and cleared the rust off of the inside of it and off of the contacts. Does anyone have any tests that I could do to try and get this to stay running? I also noticed that even though it was NOT in the forward position or the R position that I was still being propelled forward as I was trying to start it( and out of the water with it in the START position the prop only moves forward or backward about a quarter of a revoultion before it stops (as if it is in gear) Perhaps I will save that problem for another day ( unless someone has an idea about it) I am mostly trying to diagnose why it won;t stay running..... It has not ran as long as I have had it ( 2 yrs.) aside from firing it up out of the water real quick (which it sounded like it was running smooth, but my muffs don't fit well enough for me to comfortably leave it running for any period of time other than a few seconds. When in the water if I try to give it ANY kind of throttle it immediately dies. So, what do you think guys and gals? If you could point me in the right direction I will systematically do what you guys say to try and troubleshoot it. I am going to try to do as much as I can during the week, then take it out on the weekend to test it, then back to working on it during the week..etc.. so any help would be greatly appreciated

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

Was thinking about dropping all 3 carb bowls, take floats and needles out and clean with carb cleaner and see if it improves or not.... I would rather have a few things to try at once so that I can utilize next weekend

 

[phipps]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

I would definately start out by rebuilding all 3 carbs. Have you tested for a consistent spark at all 3 plugs? Have you done a compression check? Those are some starters.

I'm currently working on getting a 71 60hp going, and I'm pretty sure it's about the same motor. At least you have spark, I don't. At a minimum my points are bad.

 

[HybridMX6]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

I'd start with carbs, it could be as simple as they are very dirty and the idle needs to be set on each one. Do you have a manual for this motor or no? I'd recommend getting a factory one if you don't have one, they are pretty cheap on ebay and will direct you on how to set the idle for your engine. Just to test it out, you can get a spray bottle, pour some pre-mix into it, and squirt it directly into the butterflies on the carbs, then try to start it. If it'll start, see if it will stay running if you continue to spray premix into the carbs. If so, it's dirty carbs and/or poorly set idle screws.
I went though this same thing with my '93 60hp I rebuilt. It would not run more than a few seconds. At the advice of some members on here I did what I just suggested, and it would run if I did that. I had already rebuilt the carbs, so I started playing with the idle screws and throttlw linkage on the motor. Got her purring like a kitten now, and it'll idle all freakin day like that. I don't have a boat to put it on though right now, mine is set up for a tiller, and I have no money for all the parts required for remote.

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

Anything else I should be looking for?

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

I took the carbs off of the engine today and dropped the bowls. I did NOT see any sediment in the bowls nor did I see any of the floats being stuck or having holes in them. The carbs were pretty spotless. The gaskets that go between the carb body and the bowl looked to be damn near new. That coupled with the shiny "top", "mid", and "bot", on the bowls and the carb bodies leads me to believe that these carbs were rebuilt within the last couple of seasons. I am not too sure that rebuilding them would make it run any better than what it was chugging at before. I sprayed the whole thing down with carb/choke cleaner and blew compressed air throughout. I did NOT remove any needles after seeing the clean interior of the carbs, lack of sediment or float binding particulates. Should I just slap these carbs back together, remount and try jacking with the low throttle idle setting? If the carbs were dirty I would be more apt to rebuild them but I am not convinced that is the problem here because of the gaskets looking to be in near new shape, the SHINY words scratched on the carbs ( no oxidation or any grime dulling the scraped letters) and no floats sticking. What do you guys think? I know that small particulates in where the needles seat could cause problems, but after doucing with carb cleaner and blowing out with compressed air I did not see ANY particules drop onto my white butcher paper that I laid down to visually inspect if any particulates exited. So, once again, should I rebuild the carbs and risk screwing something up, or slap it together and risk messing up the low speed idle settings? What about carb/distributor synchronization? Would that cause my symptoms?

Thanks in advance

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

BTW- I am getting great spark on all 3 cylinders

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

I suppose instead of trying to continually bump this against the tide of new posts I will just slap the carbs back together and jack with the idle screws and see if I can't keep her running. Feel free to add your $.02 if you have anything else for me to try to do. Other than that I will post when I have it all back together, and have spun the idle screws all out of whack lol

 

[tashasdaddy]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

i scanned this quickly. but have you replaced the fuel hoses, with B1 rated alcohol resistant fuel lines? the ethanol cause the interior to deteriorate, and sluff off clogging the pickup tubes in the carbs. you have to remove the slow and high speed jets clean them and spray out the pickup tubes. flush fuel line before reconnecting to carbs.

your motor also has adjustable slow speed jets, they have to be adjusted one at a time, in the water. follow single needle adjustment here. if they are not adjusted correctly, it will never idle.

http://forums.iboats.com/showthread.php?t=167352

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

Yes, I have replaced the fuel lines with approved fuel lines ( both the primer bulb line and the main line that goes to the fuel pump along with the intermediate lines that go to each carb and the overflow line that goes to the silencer). I did notice that it had a idle set on every carb ( a pretty long shaft coming out of the front side of the carbs) and assumed that was the low speed idle set for each carb. So, I assume that I just put in water and keep turning it over by slowly turning each individualidle screw until it tries to level out then go to the next one and so forth.

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

I was looking at the thread that you linked Tasha. My only concern is that the motor itself doesn;t stay running long enough for me to check the RPMs etc

 

[domwebhost]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

So, I cleaned out the carbs and put them back on the motor. Hooked up the gas line and gave the primer bulb a couple of squeezes, hit the key and the motor fired up. It was out of the water, though. It was revving almost at WOT, and I could not understand why. Then I looked where the throttle hooks up and noticed that it was sticking so I lubricated it and moved it from WOT to reverse ( with the motor off) a few times I then put it back in the starting position and started it. The motor fired and idled pretty good. This was out of the water but I am suspecting that she should stay running in the water ( I let it idle for about 15 sec or so) and although it was slightly choppy it was a far cry better than it had previously been. I will give you more information after I take it out this weekend.

Thanks

 

[wasilvers]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

Two things that will help you with your diagnosis... a compression tester.. and a large garbage can.

Test the compression of each cylinder - quick and easy - just remove all the spark plugs, thread in the tester and crank the engine for a couple of seconds (like 5 rotations). All the readings should be close. Anything over 75+ should allow your engine to run... 120+ is even better and where you'd like to be, 100+ don't worry about it. All the cylinders should be close to each other +-10 lbs.

Once you rule bad compression out....

Pull your carbs and reclean them... if the engine hasn't run right in 2 years, trace and clean all the flow of gas. Just looking at them is not enough. Not sure how your carb works... If you have needle adjustments - note how many turns each needle takes to stop as you screw them in, then take them out and clean them. Check the holes too. With erratic running, it is usually some crap getting sucked into the gap and then causing no/low gas flow. Re install the needles till they stop then back them back out the same amount as the were when you started. If one is a lot of turns different than the others... well get a manual or find out the default settings for each. Defaults should get you running and you can adjust from there.

And for the garbage can, put it under your motor and fill it with water... you can run the engine all day there... just don't put it in gear if you can help it.

Remember, an engine is just a big air-pump... it needs compression, fuel, and fire to work. If you tested fire, then it is one of the other two.

You did replace the fuel recently and pump out the old fuel from the lines right?
And your wires are connected to the correct spark plugs?
You disconnected your primer for testing purposes? (just in case it is broken/intermittant/shorting)
New/recommemded plugs?
Fuel pump is working properly? If not it should still run when you pump the bulb - mine will idle for a few minutes till the gas is used up in out of the bowls if I forget to hook up the gas line.

Good luck and let us know what the problem was.

Will

 

[mdspoula]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

Sir, If you are by chance still having this problem I would recommend looking into the Power Pack. Mine was doing the same thing and it turned out to be the power pack was so old it was shorting out at the spot where your three wires come out.

 

[MadtownWI]

Re: 1970 Johnson 60 HP 3 Cyl. won't stay running.

I just sold my 1969 Johnson 55HP. They are similar, so here are a few pointers for those engines. My engine was completely rebuilt but still idled rough and when put in gear it would immediately die. After the carbs are cleaned, wires and plugs are new, coil wire to distributor is good, then run it at night and look just below the flywheel all the way around as it's running. I f?d around with idle one evening till I was blue in the face, it got dark and I noticed that it was arching from the distributor wires to the stator. I ran circles around the motor then drank a beer.

That old of an engine gets dry and the insulating properties diminishes over time. Any real hardware store has liquid electrical tape in a small can. Layer those terminals for added insulation. Ran perfect after that.

Also under the flywheel check the wire that goes between the two sets of points and the wires leading to your harness from there...one to ground and the other to the harness. There are two very sharp bends and from time and vibration both mine were dry and cracked and most likely shorting to ground robbing spark timing and spark all together.
Other than that, those carbs are pretty straight forward, pull those large needle valves from the top front and spray cleaner and air through those, they are the fuel/air mixture you need set for low idle.

If it runs rough it's most likely arching from the distributor to the stator. Clean the brass rings on both the rotor and the distributor too, they do get corrosion buildup.

That's about it.