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Author Topic:   OH NO! Johnson 115 Trouble

PeteB88 posted 05-25-2009 12:53 AM ET (US)
We were going to splash the the [collection of abbreviations and acronyms which mean a 1995 Boston Whaler OUTRAGE 17] today for the first time. Although we've had her since February we have had no time. So TomG and I put the muffs on the Johnson 115 and fired it up. Just like when previous owner did, it fired instantly (once I got the kill switch thing installed correctly) but went immediately to 2,500-RPM. We could not throttle it down at all; it was in neutral. So we played with the linkage and got it down to normal 850 or so but could not sustain that level.
Specifically (no manual), I traced the linkage where it connects to a rod thing that goes around the flywheel and pulled it back with my fingers after turning a limiter screw out (CCW). However, as soon as I let it go up it went.
We messed around with the throttle control lever OMC original and tried to determine if there is a linkage problem. IT seems to move freely and no binding; steering is silky smooth. The boat is in great condition.
I was wondering if any of you have had similar experience or can assist with ideas. Next step for me is to mess with throttle linkage low in starboard side of motor with knurled knob like a brake adjuster thing on a car.
We had big plans to take her out today and tomorrow - Missed Buckda and Jeff Rofling today - bummer.
I appreciate anything you can share
PB88
jimh posted 05-25-2009 11:08 AM ET (US)
Don't "play with the linkage." There are specific procedures to set the throttle plates and linkages of the carburetors. The chances that you will randomly adjust them to optimum are near zero. You need to perform the "Sync-and-Link" procedure and then set the spark advance linkage properly.
jimh posted 05-25-2009 11:09 AM ET (US)
Also: never adjust the idle speeds when on a hose adaptor. There is no back pressure on the engine and its idle characteristics will change when the exhaust is underwater.
PeteB88 posted 05-25-2009 11:18 AM ET (US)
Thanks Jim, so do you think it will go to normal RPMs once in the water? Tom and I only moved the carb inkage like you would under the hood of a car to see if we could get it to idle down. We made 850, 600 (dash tach) no problem but as soon as we let go it would climb back up to mid two thou. My Yamaha runs normally w/ muffs - 2500 RPM is way too fast, agree? No indication from previous owner of any problems but you never know.
Thanks - standing by.
PeteB88 posted 05-25-2009 11:24 AM ET (US)
Is the spark advance the thing under the fly wheel?
THX
jimh posted 05-25-2009 11:36 AM ET (US)
As in almost all classic two-cycle engines, the variation in spark timing is accomplished by movement of the spark timer base coil relative to the flywheel. There is a mechanical link which rotates the timer base. This is linked to the throttle.
The idle speed of a classic two-cycle engine is mainly determined by the spark advance because the carburetor throttle plates are already closed at idle.
PeteB88 posted 05-25-2009 11:55 AM ET (US)
Thanks Jim, so respecting your reply "Also: never adjust the idle speeds when on a hose adaptor. There is no back pressure on the engine and its idle characteristics will change when the exhaust is underwater." can we expect normal idle speed w/ motor in the water?
Your description is similar to what we have observed. It seems to us that the spark advance functions but does "return" to normal idle speed as if there is a missing return spring. Obviously we'd like to launch the boat this afternoon but if I cannot control speed and get it 1000 RPMs or below we will not have a safe situation. If you think back pressure from submerging lower unit will make a difference then we will launch.
What should we do?
Thanks
Blackduck posted 05-25-2009 12:03 PM ET (US)
Back pressure will cause RPM to drop by a couple of hundred, not a thousand or more. Being a new to you boat, I might have the engine serviced. could be the cheapest way out, in the long run.
jimh posted 05-25-2009 12:55 PM ET (US)
Yes, I agree, you won't get from 2,500-RPM to 750-RPM just from the back pressure change on the exhaust.
It sounds like--emphasis on sounds like--the spark advance at idle is out of whack.
The linkage system is complex. You need the manual or else great familiarity with it to undertake adjustments. If you can decipher what link controls what, look for an adjustment of the spark advance at idle. I would not go too far without a timing light to check the actual spark timing,
First thing--be sure the idle position moves the linkage to minimum throttle plate opening. The throttle plates should all be closed at idle. Typically the throttle plates might not even begin to open until some spark advance is applied. But this relationship depends on the engine. I am not familiar with the V4 set up.
PeteB88 posted 05-25-2009 05:03 PM ET (US)
Well, I've spent most of the afternoon messing around with the boat, not just the motor but other stuff - I did not do much to throttle linkage except confirm it is not functioning as I would expect. I cleaned and lubed a few spots including and carefully some easily accessible areas. I am now getting around 1200 -1500 RPM on muffs in idle position. What is curious is the throttle linkage responds very slowly through the cable - some hysteresis and not reliably to the same setting. My suspicions are the cable end (motor).
We'll see how it goes, Tom and I might splash her for a shakedown.
Other than that the 95 or 94 115 runs great- I did a compression test this morning 120, 122, 120, 123 or so w/ one close to 125.
Stand by for next update- - Anything from the crew would be appreciated.

Phil T posted 05-25-2009 06:09 PM ET (US)
Pete -
Woah! Easy does it with running the engine that high on the muffs. Stay below 1000 rpm's. I know some guys will ding me but it is not advisable.
Remember, running on the hose is not the same as when in the water and in gear.
Since this boat/engine are new to you, I strongly suggest you launch the boat as she is, with a pal, and run the boat close to shore/dock and diagnose the symptoms. Just bring two long oars if she quits on you.
Was the engine winterized? Could be the fogging oil burning off.
There are dozens of articles where the owner said "..ran fine while on the muffs but then got on the water and "X".." and vice-versa.
PeteB88 posted 05-25-2009 10:38 PM ET (US)
Ya, she was winterized, we burned off some of the oil a few weeks ago but I think you are right. I have been very careful and appreciate the cautions and warnings. My problem has been a totally slammed schedule all year - we were going to launch Saturday - Buckda and Jeff R were here as well as a couple of others on the site. My buddy Dale got his ribbed 21 in yesterday. I was juggling chain saws dealing with final blitz around here and a bunch of guests, fam etc. So in the middle of it all Tom G came over and we fired her up and got the high RPMs but manipulated the linkage to keep it down. No harm done, just cooled things out. This afternoon it was running better - slower and I did the compression test which was awesome. It's been a long wait to get her wet but a few more days can't hurt. I really wanted to meet up with Dave and Jeff but priorities.
I will put her in the water and see what we have. I am comparing to the 13 w/ Yamaha 40 (92) that runs fantastic. You are correct about getting to know the boat. Tom and I really wanted her in yesterday, if just for an hour, but busy ramps, crazy festival in our village right next to the village ramp scuttled our plans.
Thanks Phil - - I am seeing some slow down time next several weeks starting after tomorrow - possible quick trip to FL this or next week then I kick back for a bit.

PeteB88 posted 05-26-2009 07:20 AM ET (US)
We didn't turn any screws just "fingered" the linkage back and forth a bit.
adlert posted 05-26-2009 08:49 AM ET (US)
PeteB88,
You seriously need to pick a shop manual for your engine and then use it to perform the "sync and link" procedure before heading out. I hate to sound like an alarmist but from what I've read so far, not doing so could be playing with fire. Too much timing advance can destroy your engine. Improper settings can put undo stress on it and/or create control issues for you that can then result in an accident. Perform the basic adjustments at home and then take the book and a timing light with you to finish the job off during your first outing.
Tohsgib posted 05-26-2009 12:38 PM ET (US)
Put the darn thing in the water and she will be much lower. You want it to be around 850 in gear, not neutral.
adlert posted 05-26-2009 01:30 PM ET (US)
That's true Nick. "Loopers" in particular tend to run as higher without proper back pressure. Often as much as 700 - 900 rpm or so. Still, a proper idle speed is just one small part of the carb/timing synchronization requirements. There's good reason to believe other adjustments are out of wack on this engine at this point.
PeteB88 posted 05-27-2009 02:38 AM ET (US)
Thanks for the help, I am not entirely lame. Sometimes overly cautious. I will get the boat in the water this week for at least a motor check, probably no time to launch until the weekend - on deadline, again. Previous owner sent a real nice reply to my question about high RPM - we'll see. Main issue is motor slow to return to anything close to idle speed - on the muffs. Curious thing is my Yamaha runs awesome on muffs or in the water - difference is imperceptible.
Thanks again - Local marine motor wrench said he'd take a look if necessary. Maybe I'll enroll in Marine Mechanics Institute this winter to get the hell out of H. Siberia for a while.
PeteB88 posted 06-05-2009 09:00 AM ET (US)
You guys were exactly right on

We got her in the water for the first time yesterday - way behind the pace due to wacky schedule this year. She ran great, fantastic in fact. That 2500 on the muffs in the driveway freaked us out for sure. You guys were totally correct. What a boat and that 94 Johnson 115 runs just fine. I am sure it will suck gas from what everyone says so I will be evaluating things this year for possible repower next year. You can buy a lot of fuel for the $9K or so an ETEC or Yamaha would cost.
I will be getting me a manual and will get her out a ton this summer.
The one thing that is sketchy is the binnacle control seems real loosey goosey - the original OMC that came with the motor.
Thanks - anything else you guys can share would be great.
jimh posted 06-05-2009 09:29 AM ET (US)
[Deleted new thread begun on this topic and appended above article to this thread. Information such as this follow-up needs to be appended to the original discussion. It would be greatly appreciated if that were done instead of beginning a new discussion--jimh]
jimh posted 06-05-2009 09:31 AM ET (US)
You did not tell us the idle speed of the Johnson 115-HP V4 when in the water.
PeteB88 posted 06-05-2009 11:36 AM ET (US)
As Bart said, the motor is a bit cold blooded on first start up. Once she warmed up RPMs were around 1200 at the dock. Then down 800-1000 or so and a bit rough. I pulled the plugs when I did the compression check and they all needed to be replaced. Once we did some cruising including WOT for about 10 minutes (on and off) she would idle down with motor trimmed full down to about 600 on the dash tach while underway. Motor smooth as silk. We did many trials playing around with trim, planing speed, throttle position etc. Tach readout at neutral is about 1000 which seems high to me.
The Binnacle control seems sketchy to me, I am going to work that over before next voyage. Considering replacement.
It is tough to find sweet spot for trim and optimum cruise. Two aboard, not light weights, battery in console - wondering about Doel Fin.
Still grinding on what GPS/Finder to get.
thanks
jimh posted 06-06-2009 12:12 AM ET (US)
Some OMC motors from your era, i.e., c.1994, incorporate a warm-up circuit in their ignition module or Power Pack. The warm up circuit advances the spark timing when the engine cylinder block temperature is below threshold level. This has the effect of increasing the idle speed, as idle speed in a two-cycle motor is often greatly influenced by spark advance timing. When the engine block temperature rises above threshold, a thermal switch closes. This signals the Power Pack to go back to normal timing. The engine idle speed decreases after the engine temperature has warmed up.
The influence of the warm-up feature could have also affected your initial engine idle speed when operating in the driveway with the hose adapter. However, I am not certain your motor has that feature. The owner's manual should mention it, if the motor has it. The service manual will also describe it.

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Author	Topic: OH NO! Johnson 115 Trouble
PeteB88	posted 05-25-2009 12:53 AM ET (US) We were going to splash the the [collection of abbreviations and acronyms which mean a 1995 Boston Whaler OUTRAGE 17] today for the first time. Although we've had her since February we have had no time. So TomG and I put the muffs on the Johnson 115 and fired it up. Just like when previous owner did, it fired instantly (once I got the kill switch thing installed correctly) but went immediately to 2,500-RPM. We could not throttle it down at all; it was in neutral. So we played with the linkage and got it down to normal 850 or so but could not sustain that level. Specifically (no manual), I traced the linkage where it connects to a rod thing that goes around the flywheel and pulled it back with my fingers after turning a limiter screw out (CCW). However, as soon as I let it go up it went. We messed around with the throttle control lever OMC original and tried to determine if there is a linkage problem. IT seems to move freely and no binding; steering is silky smooth. The boat is in great condition. I was wondering if any of you have had similar experience or can assist with ideas. Next step for me is to mess with throttle linkage low in starboard side of motor with knurled knob like a brake adjuster thing on a car. We had big plans to take her out today and tomorrow - Missed Buckda and Jeff Rofling today - bummer. I appreciate anything you can share PB88
jimh	posted 05-25-2009 11:08 AM ET (US) Don't "play with the linkage." There are specific procedures to set the throttle plates and linkages of the carburetors. The chances that you will randomly adjust them to optimum are near zero. You need to perform the "Sync-and-Link" procedure and then set the spark advance linkage properly.
jimh	posted 05-25-2009 11:09 AM ET (US) Also: never adjust the idle speeds when on a hose adaptor. There is no back pressure on the engine and its idle characteristics will change when the exhaust is underwater.
PeteB88	posted 05-25-2009 11:18 AM ET (US) Thanks Jim, so do you think it will go to normal RPMs once in the water? Tom and I only moved the carb inkage like you would under the hood of a car to see if we could get it to idle down. We made 850, 600 (dash tach) no problem but as soon as we let go it would climb back up to mid two thou. My Yamaha runs normally w/ muffs - 2500 RPM is way too fast, agree? No indication from previous owner of any problems but you never know. Thanks - standing by.
PeteB88	posted 05-25-2009 11:24 AM ET (US) Is the spark advance the thing under the fly wheel? THX
jimh	posted 05-25-2009 11:36 AM ET (US) As in almost all classic two-cycle engines, the variation in spark timing is accomplished by movement of the spark timer base coil relative to the flywheel. There is a mechanical link which rotates the timer base. This is linked to the throttle. The idle speed of a classic two-cycle engine is mainly determined by the spark advance because the carburetor throttle plates are already closed at idle.
PeteB88	posted 05-25-2009 11:55 AM ET (US) Thanks Jim, so respecting your reply "Also: never adjust the idle speeds when on a hose adaptor. There is no back pressure on the engine and its idle characteristics will change when the exhaust is underwater." can we expect normal idle speed w/ motor in the water? Your description is similar to what we have observed. It seems to us that the spark advance functions but does "return" to normal idle speed as if there is a missing return spring. Obviously we'd like to launch the boat this afternoon but if I cannot control speed and get it 1000 RPMs or below we will not have a safe situation. If you think back pressure from submerging lower unit will make a difference then we will launch. What should we do? Thanks
Blackduck	posted 05-25-2009 12:03 PM ET (US) Back pressure will cause RPM to drop by a couple of hundred, not a thousand or more. Being a new to you boat, I might have the engine serviced. could be the cheapest way out, in the long run.
jimh	posted 05-25-2009 12:55 PM ET (US) Yes, I agree, you won't get from 2,500-RPM to 750-RPM just from the back pressure change on the exhaust. It sounds like--emphasis on sounds like--the spark advance at idle is out of whack. The linkage system is complex. You need the manual or else great familiarity with it to undertake adjustments. If you can decipher what link controls what, look for an adjustment of the spark advance at idle. I would not go too far without a timing light to check the actual spark timing, First thing--be sure the idle position moves the linkage to minimum throttle plate opening. The throttle plates should all be closed at idle. Typically the throttle plates might not even begin to open until some spark advance is applied. But this relationship depends on the engine. I am not familiar with the V4 set up.
PeteB88	posted 05-25-2009 05:03 PM ET (US) Well, I've spent most of the afternoon messing around with the boat, not just the motor but other stuff - I did not do much to throttle linkage except confirm it is not functioning as I would expect. I cleaned and lubed a few spots including and carefully some easily accessible areas. I am now getting around 1200 -1500 RPM on muffs in idle position. What is curious is the throttle linkage responds very slowly through the cable - some hysteresis and not reliably to the same setting. My suspicions are the cable end (motor). We'll see how it goes, Tom and I might splash her for a shakedown. Other than that the 95 or 94 115 runs great- I did a compression test this morning 120, 122, 120, 123 or so w/ one close to 125. Stand by for next update- - Anything from the crew would be appreciated.
Phil T	posted 05-25-2009 06:09 PM ET (US) Pete - Woah! Easy does it with running the engine that high on the muffs. Stay below 1000 rpm's. I know some guys will ding me but it is not advisable. Remember, running on the hose is not the same as when in the water and in gear. Since this boat/engine are new to you, I strongly suggest you launch the boat as she is, with a pal, and run the boat close to shore/dock and diagnose the symptoms. Just bring two long oars if she quits on you. Was the engine winterized? Could be the fogging oil burning off. There are dozens of articles where the owner said "..ran fine while on the muffs but then got on the water and "X".." and vice-versa.
PeteB88	posted 05-25-2009 10:38 PM ET (US) Ya, she was winterized, we burned off some of the oil a few weeks ago but I think you are right. I have been very careful and appreciate the cautions and warnings. My problem has been a totally slammed schedule all year - we were going to launch Saturday - Buckda and Jeff R were here as well as a couple of others on the site. My buddy Dale got his ribbed 21 in yesterday. I was juggling chain saws dealing with final blitz around here and a bunch of guests, fam etc. So in the middle of it all Tom G came over and we fired her up and got the high RPMs but manipulated the linkage to keep it down. No harm done, just cooled things out. This afternoon it was running better - slower and I did the compression test which was awesome. It's been a long wait to get her wet but a few more days can't hurt. I really wanted to meet up with Dave and Jeff but priorities. I will put her in the water and see what we have. I am comparing to the 13 w/ Yamaha 40 (92) that runs fantastic. You are correct about getting to know the boat. Tom and I really wanted her in yesterday, if just for an hour, but busy ramps, crazy festival in our village right next to the village ramp scuttled our plans. Thanks Phil - - I am seeing some slow down time next several weeks starting after tomorrow - possible quick trip to FL this or next week then I kick back for a bit.
PeteB88	posted 05-26-2009 07:20 AM ET (US) We didn't turn any screws just "fingered" the linkage back and forth a bit.
adlert	posted 05-26-2009 08:49 AM ET (US) PeteB88, You seriously need to pick a shop manual for your engine and then use it to perform the "sync and link" procedure before heading out. I hate to sound like an alarmist but from what I've read so far, not doing so could be playing with fire. Too much timing advance can destroy your engine. Improper settings can put undo stress on it and/or create control issues for you that can then result in an accident. Perform the basic adjustments at home and then take the book and a timing light with you to finish the job off during your first outing.
Tohsgib	posted 05-26-2009 12:38 PM ET (US) Put the darn thing in the water and she will be much lower. You want it to be around 850 in gear, not neutral.
adlert	posted 05-26-2009 01:30 PM ET (US) That's true Nick. "Loopers" in particular tend to run as higher without proper back pressure. Often as much as 700 - 900 rpm or so. Still, a proper idle speed is just one small part of the carb/timing synchronization requirements. There's good reason to believe other adjustments are out of wack on this engine at this point.
PeteB88	posted 05-27-2009 02:38 AM ET (US) Thanks for the help, I am not entirely lame. Sometimes overly cautious. I will get the boat in the water this week for at least a motor check, probably no time to launch until the weekend - on deadline, again. Previous owner sent a real nice reply to my question about high RPM - we'll see. Main issue is motor slow to return to anything close to idle speed - on the muffs. Curious thing is my Yamaha runs awesome on muffs or in the water - difference is imperceptible. Thanks again - Local marine motor wrench said he'd take a look if necessary. Maybe I'll enroll in Marine Mechanics Institute this winter to get the hell out of H. Siberia for a while.
PeteB88	posted 06-05-2009 09:00 AM ET (US) You guys were exactly right on We got her in the water for the first time yesterday - way behind the pace due to wacky schedule this year. She ran great, fantastic in fact. That 2500 on the muffs in the driveway freaked us out for sure. You guys were totally correct. What a boat and that 94 Johnson 115 runs just fine. I am sure it will suck gas from what everyone says so I will be evaluating things this year for possible repower next year. You can buy a lot of fuel for the $9K or so an ETEC or Yamaha would cost. I will be getting me a manual and will get her out a ton this summer. The one thing that is sketchy is the binnacle control seems real loosey goosey - the original OMC that came with the motor. Thanks - anything else you guys can share would be great.
jimh	posted 06-05-2009 09:29 AM ET (US) [Deleted new thread begun on this topic and appended above article to this thread. Information such as this follow-up needs to be appended to the original discussion. It would be greatly appreciated if that were done instead of beginning a new discussion--jimh]
jimh	posted 06-05-2009 09:31 AM ET (US) You did not tell us the idle speed of the Johnson 115-HP V4 when in the water.
PeteB88	posted 06-05-2009 11:36 AM ET (US) As Bart said, the motor is a bit cold blooded on first start up. Once she warmed up RPMs were around 1200 at the dock. Then down 800-1000 or so and a bit rough. I pulled the plugs when I did the compression check and they all needed to be replaced. Once we did some cruising including WOT for about 10 minutes (on and off) she would idle down with motor trimmed full down to about 600 on the dash tach while underway. Motor smooth as silk. We did many trials playing around with trim, planing speed, throttle position etc. Tach readout at neutral is about 1000 which seems high to me. The Binnacle control seems sketchy to me, I am going to work that over before next voyage. Considering replacement. It is tough to find sweet spot for trim and optimum cruise. Two aboard, not light weights, battery in console - wondering about Doel Fin. Still grinding on what GPS/Finder to get. thanks
jimh	posted 06-06-2009 12:12 AM ET (US) Some OMC motors from your era, i.e., c.1994, incorporate a warm-up circuit in their ignition module or Power Pack. The warm up circuit advances the spark timing when the engine cylinder block temperature is below threshold level. This has the effect of increasing the idle speed, as idle speed in a two-cycle motor is often greatly influenced by spark advance timing. When the engine block temperature rises above threshold, a thermal switch closes. This signals the Power Pack to go back to normal timing. The engine idle speed decreases after the engine temperature has warmed up. The influence of the warm-up feature could have also affected your initial engine idle speed when operating in the driveway with the hose adapter. However, I am not certain your motor has that feature. The owner's manual should mention it, if the motor has it. The service manual will also describe it.