Johnson/Evinrude 115hp, Not Sure Where To Go From Here

interalian

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I had a look at the BRP site and it appears the '81 was the last year to use choke flaps. If it's not too late to change your order, get '82 carbs. My '82 90 had the primer system. I adapted that system to the '79 140 carbs I used in my rebuild by grinding a flat spot on the carb base between the throats (right where it bolts to the intake), then drilling through at an angle to coincide with the passage between the two inlet ports. I removed the choke plates. One thing to keep in mind, the nipples on the carb have small orifices to properly meter the primer charge.

The bypass ports on your '81 should already have the fuel recirc valves on the intake, along with the matching nipples on the bypass ports. They're not involved in the primer system.
 

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racerone

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The electric primer was first installed on the V-4 models in 1980.------No choke flappers on 1980 models !
 

jakedaawg

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If I am reading this right, you now have 81 carbs and block...you should already have primer system components...
 

atktom

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I do not have the 1981 engine available, mechanic said he had to trade the powerhead as part of the deal. Only thing I have is the carbs off the 1981 and the primer solenoid mounted in same place as the old spring choke. Okay to make sure I am understanding, I should not put 1/16 brass nipples straight into the bypass covers and let the primer put gas straight into there by using four intake hoses ( actually 2 hoses and split on each side with a tee for two intakes one on each bypass cover on each side) as this is what I was fixing to do. Instead I should drill into carbs per your pictures. What size brass nipple did you use and how did you mount it firmly into the carbs, Also I am assuming you only used two hoses from the primer solenoid one to each carburetor. Thanks in advance.
 

flyingscott

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I do not have the 1981 engine available, mechanic said he had to trade the powerhead as part of the deal. Only thing I have is the carbs off the 1981 and the primer solenoid mounted in same place as the old spring choke. Okay to make sure I am understanding, I should not put 1/16 brass nipples straight into the bypass covers and let the primer put gas straight into there by using four intake hoses ( actually 2 hoses and split on each side with a tee for two intakes one on each bypass cover on each side) as this is what I was fixing to do. Instead I should drill into carbs per your pictures. What size brass nipple did you use and how did you mount it firmly into the carbs, Also I am assuming you only used two hoses from the primer solenoid one to each carburetor. Thanks in advance.
So let me get this straight this guy screwed you then took your money and your motor . I would be getting my money back of i was you.. What he did was ridiculous.
 

interalian

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I must have missed something. You have '81 carbs coming. These should have the primer nipples in place on the top, angled toward the motor at 45deg. Attach the 2 primer lines there.

Don't be messing with trying to put prime into the bypass covers - if OMC thought that would have been a good idea, they would have plumbed it that way. If the intake manifold doesn't have nipples for the fuel recirulcation (per the blue manifold in my prior posts), just cap the nipples in your bypass covers if they're present. If the bypass covers don't have nipples you have nothing left to do.

And per other posts, I'd be taking the alleged 'mechanic' to small claims court were this my problem.
 

racerone

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Putting the fuel into the airstream at the bypass coves is a very good way to get instant starts.----Changes are made for ease of manufacturing and money saving on the production line.----Injecting at the bypass covers works very well !!!
 

atktom

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Below is a pic of my 81 carbs and the ones I ordered are the same. My other motor the fuel line diagram showed it going to bypass covers, never went to the carbs, that is why I do not see them on the carbs. The idea I am working on now is to have a machine shop drill on center hole on each carb and attach a stud that I can put the primer hose on will have them drill it at an angle to that black spot I marked with a Sharpie and that lines up with the hole on the gasket and intake. Now my next question after looking at the mounting position of the carb, that little rectangular hole at the top kinda sits above (just a little) to the matching intake backing, so if the gasket was not there with a piece of wire I can push into that area when mounted. The gasket however covers the hole but is not backed at the top of the intake/back area. Is there any reason why I cannot JB Weld that hole flat and also the long hole at the bottom. If I can then that would seal up the carbs nicely to the block. On the outside at the top center can I JB Weld that entire area to fill in that large hole, that would make it much easier to drill for the primer hose.

Now I am not pushy and for 1750 which may be a little high I have a good motor and it does not over heat, at least for the first 10 mins have not run it longer yet. The guy who did the job is an elderly man, kinda of a strange dude as he had my motor from Dec to Mar, and his shop is out back so no working in cold weather. I just chalk it up to lesson learned and in the future will do all my own repairs unless thru some miracle I should get a new engine 2010 or later (but that is dreaming like the lottery)
.
Racerone I did notice what looks like a couple of holes under the bypass covers from the pictures in the manual but I would not know if both or one were the airstream so I am stuck on where exactly to mount them if I did them in that area and would just letting the fuel flow thru a reg 1/16" brass nipple be good enough or would I need a longer shaft to get close to one of those holes?

Thanks again for everyone's help.
 

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racerone

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I am going to be blunt here.------Take one of the bypass covers off.-----Look and understand how air / fuel is transferred from crankcase to the cylinder.-----Study and learn how the electric primer works for near instant starts.
 

spybot

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I have been in hospital or i would have chimed in long before this.
It seems you have the primer going to only to the BY-PASS covers you DO NOT need the carb mod,
The motor will/should start right up. It will start as good if not better than a fuel injected motor. The primer is shooting fuel directly into the intake ports,
Please LISTEN to Racerone !!!
The lines you have will come from below the reeds and also straight from the primer its self. These will all lead to the bypass covers where the fuel is sprayed directly through the ports and straight into the cylinder. OMC done this in 1980 the after that they added the fuel line going in to the crabs.
Your motor was designed to run this way so why change it ??????
 

atktom

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Thanks for the advice Racerone, I will comply.

Spybot hope you are doing better and are on the mend from being in the hospital.

Please remember we are talking about retro fitting a 1978 Johnson 115hp to accept
Evinrude 115hp 1981 carbs and primer solenoid.
 
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spybot

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I have 2 sets of 1980 carbs there ARE no nipples on these carbs. The only primer hoses i have come from the manifold just below each reed block and these go into the bypass covers plus the primer goes into the by pass covers.
You DO NOT need to drill the carbs.
Can you post a pic of the intake manifold and the bypass cover you have ?????
Cheers Andy
 

atktom

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Here are the pics requested. Thanks for help.
 

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interalian

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Right now you have carbs with no primer nipple, and bypass covers with no nipples either. Mod the carbs, or find bypass covers from a newer motor. The carb nipples have a restriction about 0.025" if that's helpful - jets, essentially.
 

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spybot

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The by pass covers are like these one. The intake manifold i was referring to is this one.
As interalian said you have two choices. The easiest is to find the by pass covers. But following inters pics and doing the same as he has done is also pretty simple.
 

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atktom

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Where would I find these "The carb nipples have a restriction about 0.025", I see carb nipples on ebay but not sure what size they are, if they have the .25 restriction and if I would have room to have a machine shop drill and install those into the back center of the carb. Not like my mechanic did thru the idle port. I will keep looking for bypass covers with brass intakes already installed and if I find them hope they will fit my 1978 engine. Thanks again for help.
 

atktom

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Progress report I found and ordered 3 new/old stock bypass covers 390449 for 1980/1981 engine with the studs 2 each per cover for the recirculating/primer hoses. Sure hope they fit, now just need to come up with one more and I will use those and not mess modifying the 2 used carburetors I received today to replace those that I had that were modified. Carbs were off a 85hp same part numbers, so I should only have to replace the jets from my current carbs and hopefully be good to go. Will have to block the brass studs for the recirculating hoses as I will not be using that part.
 
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atktom

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Update, I have order all the bypass covers, 2 have 2 brass studs for hoses, the others have only 1 stud on the left side.
1st question - the covers with only 1 stud for the primer hoses, is located to the left of the right side or when mounted just below where the upper brass nipple would have gone, can I just use this hole for the intake instead of trying to put one in the upper hole? I am not going to do recirculating hoses, just looking to prime/choke the engine.

2nd question is on the carbs - My 1981 carbs of course are different on the orifices than the 1978 carbs. I am dealing with 3 orifices versus 2. Manual for 1978 calls for high speed.054 and low speed .026, Now my 1981 calls for high speed .060, intermediate .028 and low .033. Was there a service bulletin making the low speed .034 as that is what is presently installed? Should I keep the 1981 carbs the same or change to what the 1978 book is calling for? Not sure what to do about the intermediate as that was not used in 1978.

Thanks for any advise, I will start modifying the engine this coming week when the weather warms up some.
 
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