New guy, bare with me. troubleshooting hard to start condition on 75 Johnson

[Av3ngeme]

Alright folks, I apologize in advance as I'm new to boating but I am mechanically inclined and am good with cars, though it seems that some of that knowledge doesn't exactly translate over very well, lol.

So I bought an old Johnson Fiberform with a Johnson 70hp on the back (70esl75e) and I've been troubleshooting a hard to start condition, after some mucking around with choke and the enrichment lever it will eventually start but it takes about 10 damn minutes.

When I got the boat it fired up attached to muffs with no issues, I had to replace the shift cable and after I did this I adjusted a the low idle and I'm afraid I may have screwed something up. Being overzealous I didn't realize that this also controls timing (again used to vehicles)

So here's what I did, using the below picture I'll try and explain. I adjusted the idle set screw as it seemed that the idle was set far too low (waiting on a tach) and it would stall. After this was done and the boat was idling by itself I noticed that the roller (marked on the pic) was not sitting at the start position when the motor was off and everything was in a neutral position so I adjusted the arm that connects the cam to the throttle lever so that it was just barely touching because where it was sitting before would prevent the cam from opening the throttle bodies all the way which would have prevented me from getting WOT. Now I'm concerned I may have screwed up the timing without realizing it, it's just a pain to start...once I do get it going it runs great and had it up to 30mph to test it out during a 30 min run and it never stumbled once....but what a pain to get going.

Now I put in 91 octane and I did some reading after I got home and found that this could possibly be a bad thing, which in my head I guess may explain why it started fine for the guy I bought it off of and for me in the driveway on muffs but after I filled the tank and tried on the water I had a hard time.

I've checked compression and it's at 120psi on all three cylinders exactly
I did a spark test though I did notice cracking on one of the coils with some arching, so I have in my possession a new ignition coil, got a new gas tank to replace the old crappy metal one that came with it.
The plugs were black / brown when I pulled them to put new ones in and it was definately getting fuel

What I'm really concerned about and i'm hoping someone can tell from my description is did I screw up the timing in my adjustments at all? I'm putting it in the water again tonight when I get home from work but I figured I'd ask to see if there's anything I can do before I go to the dock.

Thanks

 

[flyingscott]

Hello you need to do a linc and sync and definitely do not touch the WOT STOP SCREW. On an outboard motor the timing will move before the carburetors. You need to reset that cam push your throttle all the way forward and look inside the carb to make sure the butterflies are 90deg if not adjust the cam so they are. then disconnect the throttle cable and push the cam forward and adjust the roller until the butterflies just start opening at the mark then reconnect the cable and there should be a gap between the two. then try starting it. Otherwise get the manual

 

[Av3ngeme]

I'll double check that the butterflys are sitting horizontal at WOT with the shifter at full throttle, I checked yesterday but not with the shifter....however I am getting WOT out of the shifter so I'm going to assume that part is fine. I'm not following the second half of this, right now my setup looks identical to this picture..there is no gap between the cam and the roller, are you telling me that there should be? If so then the carbs will not start to open at the mark and there's no way I'll get full throttle out of the shifter. The manual that I'm following...(granted I don't really like it as it's not that clear) says to align the short mark (mine has two, one that says start and then a shorter one below it) to the middle of the roller just as it makes contact...ie no gap, so is that incorrect?

 

[Bosunsmate]

Thus is how i do it.
Set idle using idle screw so it only just runs in idle in gear that way you preserve your lower unit gears. Engine must be warm when you do this.
Make sure butterflys a closed properly
Put control throttle at full, check carbs a wide open and check timing is right
http://forums.iboats.com/forum/engi...4008-joe-reeves-wot-timing-procedure?t=228183

So long as top and bottom are done like that everything works out fine, well maybe im ljust ucky but it always has for me

 

[Av3ngeme]

Well I rebuilt all my carbs last night, the floats were not parallel to where the bowl mates to the carb so I put the new floats and adjusted. There was very slight wear on the needle valves and one of the choke butterflys was loose (the two screws that hold it on were loose so i would assume that could cause some starting issues) I checked at full throttle on the controls that the butterflys were completely horizontal, which they were. I also adjusted the throttle rod so that it was 4 31/32'nds and adjusted the roller so that it sits at the lower (short) mark on the cam. Assuming the weather holds out for me tonight I'm going to take it too a quiet launch and adjust the idle, as I assume I'm going to need to after adjusting the throttle rod and cam roller and my tach will be delivered today.

Fingers crossed!

 

[racerone]

??---There are no choke butterflies on that motor.----Are you pushing the key in while cranking it over ?

 

[Av3ngeme]

No Title

Yes there are.There are outer butterflies that close when the choke is activated via pushing in the key and the inner butterflys that move with the throttle. You can see it plainly in the picture, one set of linkages is for the choke butterflies and the other for the throttle butterflies.

*edit* I think I see where the confusion happened, the pic I posted earlier was for reference only for my other question not my exact engine, I have choke butterflies where as the pic in post 1 does not.

 

[emdsapmgr]

Just for my understanding-you said you mucked around with the choke-not sure what that means. Hopefully, when you push in on the key switch, the choke plates completely close-that's normal. When starting cold, push in on the key switch as long as you are cranking. A single push won't close the butterflys during the cranking/starting process. Once it catches, you can release the key switch choke, but may have to occasionally push in on the key switch for the first minute in order to keep it running. That engine is a bear to start if the choke does not work properly.

 

[racerone]

Perhaps the control has a seperate switch for choke.--Is the choke solenoid working and properly adjusted ?

 

[Av3ngeme]

Well after the carb rebuilds and replacing three coils it seems to fire up much better now, a little difficult when it's cold but I'm talking 30 seconds to start difficult instead of 10 minutes, lol. When warm the engine seems to like about a 1/4 lift on the enrichment lever and no choke and she'll fire right up instantly. I think it's just a matter of getting to know this particular engine and what it likes.

 

[racerone]

Even 30 seconds is way to long for a motor like that to fire up.-Also risks damage to the starter motor.-They are easily damaged by too much cranking.--Might not be a bad idea to take that starter apart for inspection and perhaps a new set of brushes.

 

[Av3ngeme]

So what would you suggest regarding the hard to start condition? Do you think the hard starting is due to the starter motor itself? The plunger is engaging the flywheel and spinning the engine fine.

 

[racerone]

???-----If the flywheel does not spin fast enuff there will be problems with no spark and a hard to start motor.-------Most folks reply to this with --" my motor cranks just fine " and they take no action.

 

[Av3ngeme]

Ahh ok, I read that wrong. So you think it's essentially a weak starter not spinning the motor fast enough causing a hard starting condition. I thought you were saying to rebuild it as a result of the hard starting condition, not that it could be causing the condition.

 

[racerone]

Sorry, I can not see , hear or feel your motor.-------Removing the starter for inspection / cleaning / possibly new brushes is a " little money spent " exercise.

 

[Av3ngeme]

As it turns out it was just a matter of getting a feel for how much enrichment the motor likes. I've got it down to a science now, 1/2 crank up on the enrichment lever and she'll fire up immediately cold or warm.