1993 115 JOHNSON IDLE PROBLEMS?

17 hoog

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1989 17' Hoog flats boat with the 93 motor I picked it up from a local boat builder as a trade in. I had the fuel tank pumped out and cleaned before use. The dealer checked the compression, rebuilt the carbs and synchronized them,replaced the water pump and serviced the lower unit. THE MOTOR STARTS, IDLES, AND RUNS TO WOT WHEN COLD but when warm the motor still runs to wot, and will ilde slowly in gear, and neutral but will die when shifted into reverse from foreward as I approach the dock. I have the service manual. HELPPPPP
Thanking you in advance,

Mark
 

OBJ

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

Welcome to iboats hoog and a very Merry Xmas to you and yours!

Can you give us an idea of the idle rpms in gear and outta' gear? May be just the rpms are to low.
 

17 hoog

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

OBJ said:
Welcome to iboats hoog and a very Merry Xmas to you and yours!

Can you give us an idea of the idle rpms in gear and outta' gear? May be just the rpms are to low.

the idle is much higher when cold maybe, 1000-1200 and when hot 700-800 I dont know when in gear maybe 100 lower
 

ezeke

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

The motor's power pack has QuikStart - which advances the timing when the engine temperature is below 96 degrees. That is why the motor revs higher when cold.
 

17 hoog

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

ezeke said:
The motor's power pack has QuikStart - which advances the timing when the engine temperature is below 96 degrees. That is why the motor revs higher when cold.

thanks that explains the high idle when cold, I will recheck all carb settings and timing
Merry Christmas and thanks again,Mark
 

OBJ

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

Using an accurate tach will help with the idle in and out of gear. Can you tell us the WOT rpms? Should be at a minimum 55K.

You can also consider taking the rig back to the dealership that performed the maint work and explain the problem to them.
 

Dhadley

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

Lets get the model number so we know what we got. If it's a 93 115, it's a crossflow and won't have Quick Start. If it has Quick Start and is a 115 it'll be at least a 1995 and will be the 60* looper. If it's a 1993 and has Quick Start, it may be a 90* looper.

That will determine where we go from here.
 

17 hoog

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

Dhadley said:
Lets get the model number so we know what we got. If it's a 93 115, it's a crossflow and won't have Quick Start. If it has Quick Start and is a 115 it'll be at least a 1995 and will be the 60* looper. If it's a 1993 and has Quick Start, it may be a 90* looper.

That will determine where we go from here.

1993 johnson J115LETS SER# G03270406- I was told is is a looper and could be upped to 140 with different jets and timing. I talked with the origional owner after the sale and he told me that had not been done, nor do I want it done. I just need some ideas where to start before I take it to the boat ramp. Also the motor does go to 5500 when I trim the boat up on plane (Hull out of water to seats no porpoising)
The dealer is out of town m-f 8-4:30 I am a large generator mech have all the tools and have aways repaired my outboards1982-200Merc included, but I finnally wore out my 1962 Sea Horse 33 on my prehistoric bass tracker and replaced it with another Johnson last year.
thanks again for all the help, Mark
 

Dhadley

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

That's a crossflow. It's already the same as the older 140 crossflows that were crank rated, not propshaft rated.

To get the longest life from that motor you'll want the top rpms in the 5800 range with an average load. At 5500 you're close enough than a prop change probably isn't needed. Just work with the set up to get the extra rpms.

Start with the basics. Check compression first even though the dealer said it's OK. If that's OK, make sure you are using Champion plugs. The (Q)L77JC4's will do just fine. Make sure the water seperator filter in new and clean - no water.

If all that works out, it may be dropping spark on a cylinder after it warms up. That motor should idle at 650 in gear.

I'd suggest, as mentioned before, you simply take it to the dealer with your concerns. If it has a problem and you mess with it, he may void the warranty.
 

17 hoog

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

Dhadley said:
That's a crossflow. It's already the same as the older 140 crossflows that were crank rated, not propshaft rated.

To get the longest life from that motor you'll want the top rpms in the 5800 range with an average load. At 5500 you're close enough than a prop change probably isn't needed. Just work with the set up to get the extra rpms.

Start with the basics. Check compression first even though the dealer said it's OK. If that's OK, make sure you are using Champion plugs. The (Q)L77JC4's will do just fine. Make sure the water seperator filter in new and clean - no water.

If all that works out, it may be dropping spark on a cylinder after it warms up. That motor should idle at 650 in gear.

I'd suggest, as mentioned before, you simply take it to the dealer with your concerns. If it has a problem and you mess with it, he may void the warranty.

The motor runs fine when hot 5500=43mph.There is no warranty bought as is, I will let you know what I find if it every stops raining and I can get to the boat ramp this weekend. Mark
 

17 hoog

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

17 said:
Dhadley said:
That's a crossflow. It's already the same as the older 140 crossflows that were crank rated, not propshaft rated.

To get the longest life from that motor you'll want the top rpms in the 5800 range with an average load. At 5500 you're close enough than a prop change probably isn't needed. Just work with the set up to get the extra rpms.

Start with the basics. Check compression first even though the dealer said it's OK. If that's OK, make sure you are using Champion plugs. The (Q)L77JC4's will do just fine. Make sure the water seperator filter in new and clean - no water.

If all that works out, it may be dropping spark on a cylinder after it warms up. That motor should idle at 650 in gear.

I'd suggest, as mentioned before, you simply take it to the dealer with your concerns. If it has a problem and you mess with it, he may void the warranty.

The motor runs fine when hot 5500=43mph.There is no warranty bought as is, I will let you know what I find if it every stops raining and I can get to the boat ramp this weekend. Mark
 

17 hoog

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

17 said:
17 said:
Dhadley said:
That's a crossflow. It's already the same as the older 140 crossflows that were crank rated, not propshaft rated.

To get the longest life from that motor you'll want the top rpms in the 5800 range with an average load. At 5500 you're close enough than a prop change probably isn't needed. Just work with the set up to get the extra rpms.

Start with the basics. Check compression first even though the dealer said it's OK. If that's OK, make sure you are using Champion plugs. The (Q)L77JC4's will do just fine. Make sure the water seperator filter in new and clean - no water.

If all that works out, it may be dropping spark on a cylinder after it warms up. That motor should idle at 650 in gear.

I'd suggest, as mentioned before, you simply take it to the dealer with your concerns. If it has a problem and you mess with it, he may void the warranty.

The motor runs fine when hot 5500=43mph.There is no warranty bought as is, I will let you know what I find if it every stops raining and I can get to the boat ramp this weekend. Mark

I forgot to ask if it does have quick start? If not why the high idle when cold?
 

ezeke

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

If it is a looper it has QuikStart.

Where did you find the model and serial numbers? Do they match the ones on the engine's welch plug?
 

OBJ

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

I believe the Model number should be J115TLETS....which is a cross flow and I don't think a looper block will fit a cross flow midsection.
 

ezeke

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

I agree OBJ, but the 115 and 120 used the same Transom Brackets and things get swapped around. Just curious.

BTW, I think you added a letter 'T' to what was written above.
 

OBJ

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

Yep....possible ezeke.

I took a look at the Part Smart model numbers and couldn't see just an "LETS" but I did see a "TLETS"...even in my extended Model Year Guide book I couldn't find just an "LETS".

I dunno.....if we go with the info we got now, high idle cold (don't really know how long it idles high) has a few possibilities.
 

17 hoog

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Re: 1993 115 JOHNSON IDLE PROBLEMS?

OBJ said:
Yep....possible ezeke.

I took a look at the Part Smart model numbers and couldn't see just an "LETS" but I did see a "TLETS"...even in my extended Model Year Guide book I couldn't find just an "LETS".

I dunno.....if we go with the info we got now, high idle cold (don't really know how long it idles high) has a few possibilities.

the numbers were off of the plate and the previous owner did not mention any power head changes so what it is it is. I was told it is a looper and I did find the let(s) on a web site to confirm a 1993 john 115. I even checked the serial # to confirm the same. Thanking you in advance, Mark
 
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