Testing the ENRICHENER SOLENOID (electric "choke") on a NEW-TO-ME Mercury 4 stroke outboard motor

[@ddvs748]

Great vid! I had trouble starting my 75hp this season and decided to check the choke. By listening to the 'click' when pushing in the key I found this thing and wondered what the hell it was and how it applied a choke to the carbs. Now I know at least how it works and how to test it. Never would have guessed it was an enrichener valve. Thanks!

[@oldhobo5610]

Glad you found it useful!

[@camerawalk]

Thanks for the video! Mine needs replacing. Warming up but not moving at all. Engine works rough and spark plugs all black. Removed it and engine started working fine. Sourcing a new valve now👍

[@oldhobo5610]

Wow, that's pretty dramatic! I didn't have much of a story to tell as mine turned out to be "no problem found".

[@josephhalwagy6435]

well done mate. Thank you for sharing

[@ryanjames5799]

Thank you for the helpful video. I purchased a boat with a 1987 Mercury 135hp and it has a crank but no start condition. Spraying starter fluid into the cylinders will briefly start it, then it dies. I am trying to work through the possible causes from, fuel, carb, spark. So far everything is checking out.

[@oldhobo5610]

Good luck then. Lots of things ro reason through and check.

[@dreamfly555]

On the Specifications' "ENRICHMENT CONTROL SYSTEM" section (Page 1A-3), the "Electrothermal ram projection" is "0.3 in. (7 mm) after 5 min. of power".

[@oldhobo5610]

Thx, I hadn't seen that spec. ( My manual for 50/60 4 stroke has it on pg 1A-2 but value is same as you pointed out). I think my solenoid under-travelled slightly, but it seems to start ok The inspection procedure on 3B-18 is not too precise ("wait several minutes", "replace...if no change observed").

[@orangewheels01]

Great video, i’m glad I found this one, my choke enricher is not even connected on my 2001 50hp 4 stroke, but it seems to start fine 🤔 I’m not sure why i have no wires going to it,

[@oldhobo5610]

Around 1:18 in the video you can see the harness coming from the right side of the screen. Your leads must be somewhere around the corner. But if it starts ok I guess you're OK! Maybe only in cold weather it would cause problems.

[@orangewheels01]

@@oldhobo5610 well since I messaged you this morning I’ve had another search around for the choke wiring and found the loom laying in the bottom of the engine bay, I’m gonna test the wires and see if there still good, as I do still have the push in choke on the ignition key 👍

[@orangewheels01]

Hi oldhobo, do you physically push the ignition key in to operate the choke or is it automatically operated? I’ve tested the two yellow wires with a multimeter while pushing the choke in on the key and there’s no power to the wires, as it wasn’t hooked up in the first place I’m not sure how it’s supposed to operate? On the key or automatically? Any help would be great thank you 👍

[@oldhobo5610]

@@orangewheels01 Based on the electrical diagram the enrichener gets its power from the stator which means it gets powered an time the flywheel is spinning. So i think the priming feature on the control box keyswitch does nothing.

[@orangewheels01]

@@oldhobo5610 Hi yes I think your right I have traced the yellow wires to the stator now myself, so it’s seems like the enricher possibility gets its power from cranking the engine and is not operated from the push in choke on the key, I have no wiring diagram for this engine so that does help many thanks 👍👍

[@7ann3]

Thanks for informative vids regarding this engine. I have the same engine but 50hp. Got a problem. It does not rev over 3200 rpm. no difference if i have it in neutral or in gear. Have read about neutral safety switch but not sure if this older 4 stroke has it. If i understan correct it is in the remote control? I am testing this on land so it has nothing to do with propp pitch and so on: would be grateful för any tip.

[@oldhobo5610]

My non-expert opinion - I'm not sure about any effect due to the neutral safety switch and if it goes into gear then I don't think the problem is in the remote box's lever control. Have you checked the throttle cable is giving full travel and the motor's throttle is actually moving fully, not binding?

[@7ann3]

@@oldhobo5610 Yes, no problem with the cables. It is like it cuts of 2 cylinders at around 3200 rpm as a safety. I have read that some engines hav this safety funktion also in the trim/tilt sensor. I thought that the remote neutral sensor have the funktion that it is not possible to start if it is not in neutral. But also limits the rpm in neutral. If it is broke in the way that it gives the control box the info that it is in neutral alt the time, even when gear is in. Then it limits the rpm,s even with gear in. i know that some older engines had this funktion but it was mechanical. So it was not possible to rev it upp to max in neutral.

[@oldhobo5610]

@@7ann3 What I see is the wiring diagram showing neutral start switch as making and breaking continuity of YEL/RED wire which leads to starter solenoid.. When key is turned to START it connects YEL/RED to PURP IGN 12v battery power (there is a swich function table) which feeds the start solenoid. As far as I can see the switch just makes or breaks your power to the starter. I can't see see feedback to the ECM or ignition, but the diagrams are complicated.

[@7ann3]

@@oldhobo5610 Hm, I hoped for this easy solution but then it something else. I will se if i can check it this weekend. Thanks for your input. I will get back to you how it turns out.

[@ernestrhoades5147]

Check your multi meter and touch the two leads together take that figure and deduct from your measurment ,thats kinda why they want you to use a analog meter.

[@oldhobo5610]

Would that compensate for what appeared to be erroneously low reading?? At start of session I usually touch leads to verify I get zero, though just to verify the leads are attached. Next time I will touch leads prior to each test to see if there is any offset. Thx.

[@davetyson2331]

it is fuel valve