120 HP JOHNSON V4 weird start issue

A

AronMIchielli

Recruit
Joined
Jan 23, 2016
Messages
2
Hi, read all other starting issue with this motor but nothing quite like that.....
Bought outboard and had a test run the other day, was very hard to start but eventually went, runs beautifully, starting issue remains when motor is warmed up too.
Had a look at carburator, all floats and butterflys are good (one was a bit bent and is now perfectly straight).
If I remove the air cover from carburator motor starts straight up, soon as I place the cover back on it wont.... By reading other forum only issue I might have is that instead of keeping prime on for 8 seconds I just push it 3 or 4 times, so will try that, but has anyone any idea why this beast will start only if I remove that cover ??
Thanks
Compression on cilinder all 4 at 120... sparkplug are good and checked, fresh fuel 50:1 motor runs perfectly after starts... issue is firing it up without the air cover

Aron
 
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ondarvr

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
With the cover off it will run leaner, by pushing the key in it will run richer. So if what you say about it starting easier with the cover off is true, then try not pushing the key in at all. And like he said, the key needs to be pushed in and held there for it to work correctly.
 
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A

AronMIchielli

Recruit
Joined
Jan 23, 2016
Messages
2
when I tried the other day I tried both ways pushing and not pushing key in, but motor will turn on only without cover, (except priming it for 8 seconds as I only found out today... I`ll try again doing this in the morning and hopefully I can go out for a fish:) )
 
B

batman99

Petty Officer 1st Class
Joined
Sep 13, 2012
Messages
393
My 1995 Johnson V4 115 doesn't like to cold condition starts either. When it did start, it would burp and shudder - like its idle RPM was set too low. Many folks have told me the OMC engines don't like cold state. But after warmed up, they run great. Then, I learned about its Fast Idle lever (on the OMC controller). Now, I start with chock (key pressed inward while engine cranks) and its fast idle control lever all the way up. Let the engine warm up (as I continue to load gear and people - while boat secured on its power lift / with its lower end within water). And every 2 minute internals (or so), I lower its fast idle lever 1" down. By the time I finished loading (re: 3-5 minutes later), its warmed up and runs perfect. And, when I put into gear (to back out of the dock area), she runs great (due to a warmed up engine). When starting cold, remember to have a hard primer bulb and use the fast idle lever.

If you don't know already, the fast idle lever is shown as 45 degree background lever within: https://encrypted-tbn1.gstatic.com/i...ZTFvgrkpV86E_7

Note: I sometimes need to use the fast idle lever when engine is low warm state (like resting at a shoreline beach and restarting 30 minutes later). Engine is warm to touch (from previous run) but not warm enough to start on its own. re: Needing some minor help with its fast idle helper lever always works.

Suggest removing the engine cover, pull the emergency cord on the OMC controller unit (so engine won't start), put into "N" gear and have a buddy move the fast idle lever. As he/she moves the lever, look on the engine and see what parts are moving. Sometimes, this fast idle level needs fixing &/or adjusting. Especially if boat mechanic didn't investigate this control - before you bought the boat. Also....Fast idle lever will only work if OMC controller is in "N" gear.

Hope this helps.
 
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T

tommarvin

Ensign
Joined
Nov 22, 2015
Messages
999
Time to rebuild the carb(s), Remove carb tear it apart, spray cleaner and compressed air in every hole and tube.

order a rebuild kit from Iboats.com, go to www boatinfo.no/lib/library.html. Click on your motor maker, find your carb and put it back together correctly.

Just throwing it out there, it's probably push key to choke, and fast idle all the way up to top, max idle throttle .
 
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