General Questions about a 1976 115HP Johnson

[boatflipper]

I am headed to pick up a 1976 115 HP johnson either friday night or saturday morning. Found it on craigslist for $200 and figured it was worth it. I have been looking for a good one for my 'Twain...
Anyway, other than compression and checking the gear oil in lower unit for metal flakes and/or water, what else should I check on? He says the power tilt works so I figure that is worth the asking price...
Any thing these motors are known for?
Thanks!

 

[TN-25]

Re: Picking up a 1976 115 HP Johnson

Re: Picking up a 1976 115 HP Johnson

I have heard (uh oh, that is how Internet rumors start) that the CD magnetos on those mid-1970 V4 motors can sometimes give trouble. It may stem from water intrusion through the cowling under certain conditions (tilting motor during a monsoon for example ). They either work 100% or they fail at great replacement cost.

Make sure that you get a proper working Powershift II throttle control with the motor (Powershift II was used starting 1973); also be on the lookout for any backwoods electrical fixes on the controls and motor itself.

Personally I'm a fan of those V4s. Basically there were pretty good motors. By that time OMC had eliminated the overboard drains (no more oil slicks). 50:1 mixtures were tried, tested and true by then (been in use since 1964). Tilt-pin steering came in for 1973. I would say that parts should not be a problem for that motor, although power trim n tilt components may be either a little hard to find or expensive when you do.

**Please remember that I am masquerading as an expert; the real experts are free to correct anything I have mis-stated.

 

[boatflipper]

Re: Picking up a 1976 115 HP Johnson

Re: Picking up a 1976 115 HP Johnson

I have heard (uh oh, that is how Internet rumors start) that the CD magnetos on those mid-1970 V4 motors can sometimes give trouble. It may stem from water intrusion through the cowling under certain conditions (tilting motor during a monsoon for example ). They either work 100% or they fail at great replacement cost.

Make sure that you get a proper working Powershift II throttle control with the motor (Powershift II was used starting 1973); also be on the lookout for any backwoods electrical fixes on the controls and motor itself.

Personally I'm a fan of those V4s. Basically there were pretty good motors. By that time OMC had eliminated the overboard drains (no more oil slicks). 50:1 mixtures were tried, tested and true by then (been in use since 1964). Tilt-pin steering came in for 1973. I would say that parts should not be a problem for that motor, although power trim n tilt components may be either a little hard to find or expensive when you do.

**Please remember that I am masquerading as an expert; the real experts are free to correct anything I have mis-stated.

Thanks a lot TN! That is exactly the kind of stuff I am looking for.
The guy says the key is broke off in the keyswitch...can I just buy the keyswitch or will I have to buy the whole sha-bang (control box).
Thanks!

 

[boatflipper]

Re: Picking up a 1976 115 HP Johnson

Re: Picking up a 1976 115 HP Johnson

Well I'm a proud (I think) new owner of a 1976 115 HP Johnson!
I picked it up today for $200.
I will try and get some pics up tomorrow.
Very happy with the way it looks-under the hood is very clean and all the wiring is in excellent shape-no splices and the plastic coating is not dry
rotted.
Only issues are:
The keyswitch is gone, lower unit has some nasty dents and dings-hopefully it still functions properly-may invest in a new lower end down the road-pictures will show what I am talking about. The tilt also leaks off after a while...any ideas?
I will elaborate further once I check it out a little more!

 

[emdsapmgr]

Re: Picking up a 1976 115 HP Johnson

Re: Picking up a 1976 115 HP Johnson

Get an original factory service manual from Ken Cook, Co. in Milwaukee. Take a compression check. I'd look for compression in the 120+ range. If the engine was not put up for storage properly and it has been sitting for a long time, you may have dried fuel in the carbs. You may want to pull them apart and overhaul them. I'd put a new impeller in the lower unit, so you know that will last you for a few years forward. When you run it, check the temps on each head to make sure the thermostat (vernatherm) is not stuck shut and causes an overheat-it is cheap-you may want to just replace it. Check for solid spark on all 4 plug wires. Make sure the power trim reservoir is full and then bleed the unit in case it has any air in it-then decide if it still leaks.

 

[boatflipper]

Re: Picking up a 1976 115 HP Johnson

Re: Picking up a 1976 115 HP Johnson

Thought I would post some pictures of her....not that you guys don't know what one looks like

I am still trying to find a keyswitch for it-having a hard time finding one to fit inside the control box. I guess I will just keep searching ebay!

 

[boatflipper]

Couple questions about a 1976 115HP Johnson

Couple questions about a 1976 115HP Johnson

Well I ordered a new keyswitch for it ($45).
Once that comes in I will be ready to try and fire her up.
I finished hooking everything up today...

I do have a couple questions...
1. There is a black wire coming from the power tilt unit. What does this go to?
2. My throtle box was being a little hard to get along with today and it didn't want to shift into forward. It would go to reverse and neutral but felt like it was lodged when trying to shift into forward. I of course lifted the safety button on the bottom of the control lever and still nothing. So, being the do-it-yourselfer that I am, I dis-assembled the control box. After taking everything apart and cleaning the gunk out, I put it back together and it seems to be working good. However I have a little ball leftover that was rolling around in the box. I saw a little spring inside the box that goes against the shaft that the lever attached too and was wondering if it goes in that. I cant find anywhere else for it to go.
3. Where is the oil fill for the power tilt and trim?

Thanks for the help!

 

[emdsapmgr]

Re: General Questions about a 1976 115HP Johnson

The wire may be for a trim gauge. The chrome ball is probably the one that holds the shifter in neutral-it should click when you shift from neutral. It goes in a channel and has a spring pushing it. See the parts list diagram at epc.brp.com. There should be a plug/screw on the side of the power trim reservoir. Fill it there to the bottom lip of the hole. Power trim is always a nice feature, a rarity on many engines this old.

 

[boatflipper]

Re: General Questions about a 1976 115HP Johnson

The wire may be for a trim gauge. The chrome ball is probably the one that holds the shifter in neutral-it should click when you shift from neutral. It goes in a channel and has a spring pushing it. See the parts list diagram at epc.brp.com. There should be a plug/screw on the side of the power trim reservoir. Fill it there to the bottom lip of the hole. Power trim is always a nice feature, a rarity on many engines this old.

Thanks!
The power trim wont hold when the motor is all the way up. It leaks off immediately once i quit pushing the button. Would this be due to low levels of fluid?

 

[ezeke]

Re: General Questions about a 1976 115HP Johnson

You have a Prestolite PT&T pump which has the fill plug on the side of the reservoir. Use only OMC/BRP fluid or Dextron ATF.

You may need to refill the reservoir several times and cycle the motor up and down several times after each addition before you clear any air in the system. Be sure to support the motor whenever the fill plug is removed.

Check that the manual release plug is torqued to spec. (45-55 in lbs.)
Look for leaks in the lines and around the cylinders.

 

[boatflipper]

Re: General Questions about a 1976 115HP Johnson

SO I have been making progress with the motor...
I managed to install the keyswitch and wire it properly I guess I wired it correctly because she turns over, and the automatic choke works too
I do have a slight problem however When I crank the motor over and engage the choke, then dis-engage the choke, gas pours out of the carb. Is there a line stopped up that is keeping the gas from going to the motor?? Any thoughts would be appreciated!!
Thanks!!

 

[ezeke]

Re: General Questions about a 1976 115HP Johnson

SO I have been making progress with the motor...
I managed to install the keyswitch and wire it properly I guess I wired it correctly because she turns over, and the automatic choke works too
I do have a slight problem however When I crank the motor over and engage the choke, then dis-engage the choke, gas pours out of the carb. Is there a line stopped up that is keeping the gas from going to the motor?? Any thoughts would be appreciated!!
Thanks!!

No, most likely that your float valves are not working. When you rebuild your carburetors, be sure to use kits and install the new float needles and clips.

The way the system works is that the primer bulb and fuel pump fill the float bowls at the bottom of the carburetors and a needle valve in each carburetor is supposed to prevent overflow. The fuel is then pulled, not pushed, through the carburetors by the vacuum created by the pistons.

BTW, what's the model number on the welch plug on port side top of the engine; those are not 1976 ignition coils.

 

[boatflipper]

Re: General Questions about a 1976 115HP Johnson

No, most likely that your float valves are not working. When you rebuild your carburetors, be sure to use kits and install the new float needles and clips.

The way the system works is that the primer bulb and fuel pump fill the float bowls at the bottom of the carburetors and a needle valve in each carburetor is supposed to prevent overflow. The fuel is then pulled, not pushed, through the carburetors by the vacuum created by the pistons.

BTW, what's the model number on the welch plug on port side top of the engine; those are not 1976 ignition coils.

Thaks ezeke.
You think I could do these myself? I was able to do the ones on my 1966 and 1965 Evinrude 33hp's. Is there anything more complex on this one than those?

And about the model number you requested: I dont exactly know what a welch plug is...I can tell you that the guy I bought the motor from said that the ignition coils are new...

Thanks!

 

[ezeke]

Re: General Questions about a 1976 115HP Johnson

Thaks ezeke.
You think I could do these myself? I was able to do the ones on my 1966 and 1965 Evinrude 33hp's. Is there anything more complex on this one than those?

And about the model number you requested: I dont exactly know what a welch plug is...I can tell you that the guy I bought the motor from said that the ignition coils are new...

Thanks!

You can do the carbs, but buy kits before you start. You probably should get new hose for them as well unless they look new.

Crossflow carburetors are about as easy as any, but you have to take your time and be careful. Pull a rag under the carburetors while you work so when you drop parts you can find them. These are similar: http://www.youtube.com/watch?v=o5cxBMDezuU

 

[boatflipper]

Re: General Questions about a 1976 115HP Johnson

Thanks again for the help...
I looked at iboats store and they have a carb kit but is doesn't have the floats... do I need new ones or would the old ones be ok since there will be new needles and such??
Also, you mentioned this is a 'cross-flow' carb...i noticed in iboats store that the only carb kit designed for a cross-flow is for a V6 but I have a V4

Also, any thoughts on the ignition coils?
Thanks!

 

[ezeke]

Re: General Questions about a 1976 115HP Johnson

The floats are closed cell and last a long time. If you want complete kits, use OEM from a BRP authorized dealer. Select service option and enter area code here: http://www.evinrude.com/en-US/Find-a-Dealer

The aftermarket kits work fine but don't have the floats. OEM part # is 0439076 - you need two.

The Sierra kit w/o float is part 18-7046: http://www.iboats.com/mall/partfind...gd_poid=109334&gd_row=81&**********=295673111

 

[boatflipper]

Re: General Questions about a 1976 115HP Johnson

Well I finally got the carbs rebuilt this weekend.
I pulled everything off, rebuilt them overnight, and put them back on Saturday morning. I was pumping the primer bulb and saw gas leaking from the bottom carb Turns out, there was a cracked line dummy me didn't replace. I was not a happy camper. So, after I pulled everything back off, replaced the line, and put it all back on, I pumped her up again. No leaks so I went to the key. This was the moment I had been waiting for. My heart was racing. I was so ready to hear this beauty fire. I lift the electric choke switch and commence the turning of the key. She begins cranking and as I let off the choke, gas again pours out of the top carb
What in the blue blazes is goin on guys?!?!?! Before gas came out of the top and bottom carbs so I replaced the needle valves, along with various other gaskets, hoping that would fix it. Well the bottom one seems fixed but the top one obviously isn't. Could the top needle vavle still be sticking?

Any thoughts would be appreciated.

 

[emdsapmgr]

Re: General Questions about a 1976 115HP Johnson

It is unlikely that the new needle and seat are bad. You may have the float adjusted incorrectly. There is a spec in the factory service manual for it. If you did not replace the floats (if the original cork float was reused,) it may fuel saturated and it may not actually float-it may be sinking-causing the flooding in the top carb. Back in 1976 there was no ethanol in the fuel. Your engine was may still have those early hoses which are susceptible to deterioration when used with ethanol fuels. They can break down and bits of the hose can float through the system and lodge in the carbs. If they are original, you might want to replace them all. All replacement factory hoses are all ethanol compliant. Also, if the hose makes a hard bend, the factory makes them special that way by heat forming and they have part numbers for each.

 

[ezeke]

Re: General Questions about a 1976 115HP Johnson

Turn the carburetor upside down; if you have the floats set so that the face is parallel with the carburetor body, the float valves should close. While you have the carburetor upside down, blow into the fuel line; if you have the float set correctly, nothing will go through.

 

[boatflipper]

Re: General Questions about a 1976 115HP Johnson

Gosh it has been too long since I got on here!!
This past weekend I finally got the ol' motor goin. Turns out, I hadn't properly cleaned the carbs, and I had the ignition switch wired wrong.
I knew it was wired wrong because I had to push in on the switch when in the start position fir it to turn over-that should be to choke it. So, I put a newer design switch on it, turned it and the motor fired right up and purred like a kitten!
I took it out on my Mark Twain that is currently undergoing restoration and it did a great job pushing it!! I would guesstimate that I topped out at 40 mph.
Well, now I can really get goin on the restore now that I have a motor that will actually run!
Thanks guys for all the help!!