1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Hello and thanks for stoping by.
1977 Johnson - 115HP (V4 I think) - Model: 115EL775

Here is the story: I recently purchased my first boat fairly cheaply knowing that although the engine would start, there was quite a bit wrong with the boat. Having worked through all the other problems I am now wanting to get it on the water, but I need to fix the idle first.

I am pretty sure a red-neck owned the boat prior to me, but I grew up on a ranch so fortunately I speak the language, but the throttle and drive system are the most "country riggin" I have ever seen.
1. The trottle system still ties into the Johnson Command Center (anyone have a diagram of that? Basically the Control Box - starter, throttle adjustment, drive, etc )
2. The (lower) drive cable attaches to a seperate lever on the console(I plan to fix this if I can ever find the correct cables and connections and as money allows) I will provide pictures as its kinda funny and hard to explain.

For testing purposes I set the drive system to netural
Started the motor with the "fast idle arm" pulled to the top, and the motor will start at very high RPMs, but when I lower the idle arm(even after the engine has run for a few min) to the bottom the engine will die. I want to make sure I have my idle good prior to trying to test it out on the water.

I have ordered the manual, but while waiting I thought I would ask you guys for any suggestions of the best way to tune the idle. I will include pictures of the componets etc tonight.
Thanks
Roy

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

check compression, rebuild the carbs with a kit for each carb, got to engine faq, read awakening a sleeping outboard.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

About 90% of the time a carb rebuild fixes the symptoms you describe. Standard operating procedure for new-to-you motors that have been sitting a bit:

1) Replace Impeller
2) Rebuild Carbs

Let's see some pictures of the country riggin'. It's quite possible someone rigged up a later set of cables to work with that motor. I inherited one of those.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

you should be on the water to set your idle anyways....650 under load

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

So, I have read the article "awakening a sleeping outboard" and the first thing HighTrim ever said to me was to check the impeller. Because I am a total newbie I assumed this was the bilge pump (sorry)

The delema I am running into (and this seems to apply to several parts I have looked at so far) is there seems to be a gap around the 1977 model. Is this due to a specific reason?

For example when looking to see what I would need if the impeller did need to be replaced I was searching:
http://www.iboats.com/Johnson_Impel...7470549--list_time.1191271739--view_id.271270
but it seems that only have impellers from 1979 up. I also noticed this when looking at a few other parts (making me suspect that the "country rigging" for the drive was a result of having to do things that way)

1.) I am going to clean carb (I am not especially mechanical so I am going to approach this step very cautiously)

2.) Is there a way I can test the impeller? I do not notice after running the engine for a few min that it seems very hot. I also do not appear to have a temp gauge so I am not sure if it is hot or not. There is water that ejects from both sides (I guess "peeing") of the shaft while the muffs are on. Also from the few forms I have seen it appears that relacing that impeller on this engine will be a real pain:
http://www.outboardmotor.biz/t/016086.html

HT I assume "650 under load" means on the rpm's on the tac? (havent checked to see if the tac is even working yet) I also am unsure exactly how to adjust my idle, but there is a turn knob on the front of the "Johnson Command Center" which says throttle something so I will start there.

Thanks for the tips so far.

(side question: I can start another thread if that is more appropriate). I need to confirm that bilge pump is working, what is the best way to do that?)

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

'78 was a model change year. So, your '77 is going to be a little tougher to find parts for using online sources. Dunno why, since there's plenty of parts being made, but iboats and the other sites don't seem to have that figured out.

That turn knob is your throttle tension. The idle adjust screw is on the motor.


Did anyone say manual yet?

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Hey Wombat, (ok.. to be honest the first thing HighTrim said was not "check your impeller" but was actually "get the manual") I hear you on the manual, but I am afraid now that I read the "Awakening a Sleeping Outboard" faq I may have made a mistake on that too. I ordered
Seloc - Johnson Evinrude Outboard SE1308
60-235 HP Repair Manual
1973-1991

They shipped it today so I should have it in my hands soon.
But now I am thinking I should have done some more research and tried to find the OMC manual :-(

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Here is the page that you need for your impeller.

http://www.iboats.com/Johnson_Impel...4783824--**********.418412325--view_id.271268

your idle adjust screw will be on the motor like iwombat said behind the throttle cam, about the middle, starboard side.

The bildge pump should be easy, there will probably be a switch for it on the control area. If it runs it works, not much to it.

And yes, sorry, it is 650 rpm under load.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

That OMC manual is really the ticket. That said, impeller and carb are covered pretty well in the seloc. That and a few questions here will get you through. I can provide the rest from my '77 manual if you need it, AND it doesn't require typing a book.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

FWIW, my last impeller came from NAPA.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

For the 115HP, there is almost no difference between the OMC service manuals for 1976 and 1977 and/or either Johnson or Evinrude. You will usually be able to find one on Ebay for very little money.

Once you have one and have cleaned the carburetors, follow the proscribed link and sync to solve most of the idle problems, and do it by the numbers.

Try Ebay .com and enter the number in the search window: 220117161754 or
200144547785

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Its amazing what a little carb cleaner will do. It is idling pretty good right now but I am still concerned with the way the throttle and drive are cabled.

I have attached the pictures "country rig" , the command center and the throttle/drive cables on the outboard. In the picture the "country rig" is the cabled rig outside which is for the forward/reverse.

I have a couple of questions based on the rig.
1. Does it look like it will work (till I can replace if I can find the part)?
2. How bad would it be if I did not have the drive and throttle engaged at the same time? (for example the "country rig" all the way forward, but the throttle only 1/2 way etc ?)

This is also probably a newbie question. I am concerned about going from forward to reverse. Even at idle I can hear a short clicking when I first engage from forward to reverse. I imagine that in the water the prop will be under much greater resistance than in the air, so it may be a mute point but I thought I would ask.

I am also concerned about the impeller because it has come up several times in threads. I ran the engine at idle for about 5 min with the muffs on, and felt the engine forheat. The engine did not seem to get that hot, so I am curious as to a way to test the impeller ias t looks pretty tough to have to replace. I also noticed after the run the shaft to the lower unit was warm. In addition when I removed the hose from the muff the water was warm (good or bad sign?)

Thanks for any comments

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Lots of V4 motors were run on two levers instead of one, so that should not pose a problem.

You should not shift quickly from forward to reverse. the quick shift is from neutral and only at idle. That was a major advantage of the single lever control - that you had to lower the speed to shift and you could not go into gear with the warmup lever raised.

If you want to add a telltale, you can always tell if the water pump is working. It would cost about $20. in parts. See the first thread on this forum.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Replacing the impeller isn't that hard, really. Not replacing it, and having it fail (a real possibility) could leave you with a toasted motor in a pretty short period of time. So, you gotta ask yourself if you're feeling lucky.

"Well, do you feel lucky, punk?"


Looks like the jury-rigging will work, but you gotta wonder why its there. You'll want to open up that console and figure it out. If the inside of the console is toast new ones can be ebay'd for under $100. It may just be that he never bothered to get the idle working properly and the solution was to idle it high and shove it in gear.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Hey watch the redneck comments!

I dont see a thing wrong with the cables on your boat, at least he tried to weld it. LOL

Here in Mississippi most cables are some what like that , most times there is only one cable and the boat operator nees to run to the back to shift Hahahahahahahahaha .

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

iwombat said:

FWIW, my last impeller came from NAPA.

Click to expand...

If the water pump housing is original, you will have to buy the improved water pump and impeller. These can be had from a Johnson/Evinrude dealer for right at $90. If the housing has been upgraded only the impeller is needed.

Before getting to the impeller, check the spark(Joe Reeves has instructions for a homemade spark tester on this forum), check the compression, then check the lower unit for water contamination. If any of these are compromised, look for another motor. If not, all the other advice applies.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

Ok, I have a couple comments/questions in follow up.

The first is in response to ezeke's comment of adding a tell-tale. Although I admit that iwombat wrote an excellent article on adding a tell-tale I am not so mechanically inclined where I would feel confident in doing that mod just yet. However, if I understand what you guys are saying that is the only way to confirm your water pump and impeller are working correctly?
--
Second in response to iwombats "Well, do you feel lucky, punk?"
I am not a lucky man by nature, but I also have a pi$$ed off wife right now and I am trying to keep the cost down as much as possible (talked her into letting me get the boat, but when I didnt hit the lake right away she thinks I got taken by the guy who sold it to me). I need to get the boat on the water and show "hey baby, look how much fun we are going to have" and then tune things as paychecks allow (as my fishing partner would say "Man, you aint got no pull with the wife")
So, I want to take the boat out for its first test run this week. If I was 52% confident in my impeller/waterpump were working correctly, how long could I run the engine without causing any damage (5 -10 min, 2 min, 30 min, till engine is hot to touch, none?)
In regards to "gotta wonder why its there" on the throttle cable, yes I do wonder why its there, I was hoping you guys would tell me something like "they dont make the 77 cables anymore" or something like that. Also, on the "Johnson Control Center" I did take it apart already to poke around. I cant see anything obviously broken (may upload some pics on that tonight). Of course the ball bering poped out and I didnt know where it went, but in reading other threads I think I have that figured and i will correct that tonight (need to use the hex) I cant wait for the dang manual to get here.

Would someone mind explaining the Throttle Tension knob? When I took the command center apart that was the componet that I couldnt figure out exactly. What is it for, and how should it be adjusted?
--
In response to rudedude, I was born a redneck, and will die a redneck, but as one of the country boys I do find myself mocking our hick ways sometimes
--
in reply to burroak, I dont have the manual yet and this is my first boat. I did not grow up around boats so short of going out with my buddy Simon on his boat I really have no experience to speak of so until I get the manual I dont even know:
1. where the water pump housing is
2. Where exacatly the impeller is at
3. I will look at Joe Reeves article today, but I think my spark is ok as I am idling fine now
4. How do I check the compresson?
5. Checking the lower unit for water contamination. What do I check for in this step, and how do I accomplish it?

Thanks so much for the advice so far, you guys have saved me litteraly hundreds of dollars with your suggestions.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

phew! big post.

In order to use the earlier throttle cables, there's a seperate cable end that maybe cracked, or broke or something and was hard for him to locate. Since sea-way is my local dealership I have no idea what's really hard to get anymore. They have everything. So, my guess is that's some weird homemade cable end he made instead of buying a replacement.

That impeller is going to cost you $25. If you replace the whole water pump and housing, it'll cost you more, but you can put that off if you have to. You'll just suffer a bit of efficiency and life on that new impeller.

If you gotta, gotta run it, give it a long warm up (like 15minutes) and check the engine temperature by hand prior to leaving the dock. You should be able to place your hand on the block for a 3-count before going "ouch". At least you'll know it's cooling okay at idle. You'll want to check it again after your first full run.


I'd be explaining to the wife that it's running good now, but there's some maintenance items that may or may not have been neglected and need to be addressed. This is about protecting what you have, not about getting it working in the first place. Give her the benefit of the doubt on that, she may surprise you.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

To check the compression, you will first need a compression gauge, I prefer the screw in type but others may disagree. Bring your motor to operating temperature. Remove all of your plugs. Screw the gauge into the first plug hole. Turn it over 6 to 7 times or until the gauge reaches its "peak". Record the reading. Continue with the remaining cylinders. Although a tell tale is a handy visual, even with it you will not be able to shut your motor down quick enough to avoid damage, even if you are watching it like a hawk. You will have water exiting other areas on your lu, just not as much as you would from a tell tale. Water will exit around the prop with the exhaust for example. Bottom line, change that impeller, it really is not as hard as you may think, even easier with a manual. When you change your lu oil, you will be able to tell if you have water intrusion. Watch the first bit that comes out, the water will sit at the bottom. If it looks like a milkshake, or off white, you have water. Also watch for metal filings on the drain screw, it is magnetized. Make sure you change the gaskets for the vent and drain screw every time you change the lu oil, that is the number 1 spot for water intrusion. Now that stop screw in your control box. It is for adjusting the throttle cam. The throttle cam on your engine is marked START. When the warm up lever on the control box is moved to the START position, the START mark on the throttle cam should center on the cam roller. If it does not, that is when you adjust the stop screw in the control box in or out to obtain proper adjustment This will need to be adjusted if you change the engine idle speed . The cam will be on the starboard side, about center.

Re: 1977 Johnson 115hp - Does not idle well - any suggestions would be helpful

oriley auto sells most boat parts