Tower Of Power -Let's talk plugs!

[Bronkitis]

Hello everyone. New to both the forum and the boating community. I recently purchased a 1978 CalGlass 17' run-a-bout )which I know little about) with a Mercury 115 tower of power on the back. When I purchased the boat, the motor wouldn't start COLD without a bit of fuel sprayed into the carbs. Once it fired though, it seemed to run GREAT and start with just a bump of the key. Never have I seen a motor start so fast once this thing warms up! But, I still cannot get it to start cold.

It has an electric choke that doesn't seem to be working properly and the manual choke on the motor doesn't stay up on it's own (?). I looked at the plugs and they are indeed the BUHW's that I have read so much about. I have also read a whole bunch on how these beastly motors are terrible to wake up when they're cold. On top of fixing the choke, would I benefit at all from running the BU8H or BUHW-2 plugs? I've read they run a little hotter and could help a hard-starting motor such as the one I've got.

Any help is GREATLY appreciated!

AJ

 

[redjmp]

Re: Tower Of Power -Let's talk plugs!

Well you need to check why the electric choke is not working.
Premix tends to foul plugs if idled too long.
I wipe my buhw's down before every outing.

 

[aussieflash]

Re: Tower Of Power -Let's talk plugs!

Are you using correct starting procedure?Is it a push key choke/enrichner?
1ump ball firm,2pen tank vent,3pen throttle(neutral),4:Turn key to on and push in for 5 seconds(should hear click from engine) then start,5:lower throttle as soon as it kicks.
Very easy to check if enrichner valve is working,just pull feeder hose while activating push key.

 

[Bronkitis]

Re: Tower Of Power -Let's talk plugs!

I don't believe it has a "fuel enrichment" on the key; too old? The electric choke is a small black button above the key. There doesn't seem to be any wires for it though. I see a 3 prong connection at the front of the throttle assembly which I am assuming is the choke. The manual choke, however, is buried under the cover. When I lift it, I can see the butterfly's close but for some reason it dpesnt want to stay up on its own. I haven't fiddled with it much yet.

Like I said, when she fires, she runs great and starts even better. Also, noticed the motor didn't like it when I threw the cover on while JT was tuning. It choked out and died the first time I'd done it. It fired back up and ran okay again afterward. Just kinda weird.

As for the other starting procedures it's got fresh fuel with 50:1 mix, fuel tank vent is open, throttle is up and ball is firm. I read somewhere theae things love fuel so much that a guy had to tilt his to flood the carbs and gret it to fire. Cold blooded beasts!

How about them plugs?

Thanks again.

 

[turtles11756]

Re: Tower Of Power -Let's talk plugs!

check the wiire on electric choke maybe rotted. fix the manual choke prime the fuel bulb hard and it will start cold. post serial # and that will show the champion plug motor was originally made wth. not that the the ones it has now are no good they are

 

[Texasmark]

Re: Tower Of Power -Let's talk plugs!

Let's get back to basics. Having the manual choke that won't stay up, tape it up if you have to or get someone to hold it up. Squeeze the bulb on your cold engine till firm, and with the throttle 1/4 or so open, and a fresh battery with clean terminals all the way, attempt to start the engine. If, after a few revs it lights off, wala you solved your problem. On starting a cold Merc, if it doesn't get choked it doesn't start, being it a conventional venturi close off shutter like days of old, and like your manual choke does, or the newer "fuel enrichment valve" that just dumps fuel into the intake manifold. So, if it doesn't work, hook up your electric choke!

Mark

 

[Chris1956]

Re: Tower Of Power -Let's talk plugs!

The electric choke is a must for convenience. Removing the wrap cowl is a drag. You should have choke shutters on the top two carbs. To start her, pump up the primer bulb until firm. Lift cold start lever all the way. Hold the choke button down and crank her until she fires. Feather the choke and then the cold start lever as she warms up.

 

[Georgesalmon]

Re: Tower Of Power -Let's talk plugs!

Yes to all above. Mine won't start cold unless I prime the bulb hard everytime when cold. Then she starts great.

 

[Bronkitis]

Re: Tower Of Power -Let's talk plugs!

Ok, so I need to get my choke working. Can someone confirm that the 3-prong plug I see at the front of the throttle assembly is indeed for the choke wiring? How does one wire that back up? It appears as though nothing is there...

 

[RonnieD]

Re: Tower Of Power -Let's talk plugs!

That 3 pin plug has a brown wire for tach signal,A white wire for 12 V ign ON, and a black 12 V ground wire for gauges,etc.The choke button should have that same white wire and a gray wire going back to the choke sol.



\\

 

[RonnieD]

Re: Tower Of Power -Let's talk plugs!

Well,If I can figure out how to post a diagram correctly>>>

 

[RonnieD]

Re: Tower Of Power -Let's talk plugs!

Sorry,I cant get the diagram to go full size...

 

[Bronkitis]

Re: Tower Of Power -Let's talk plugs!

Interesting! Looks like I'll be tearing the controls apart this weekend along with the steering cable. The boat needs to be completely re-wired as far as any accessories go. Hopefully, I'll get the choke working again and that will get her starting cold. I really appreciate all the help.

 

[s.hadley81]

Re: Tower Of Power -Let's talk plugs!

Interesting! Looks like I'll be tearing the controls apart this weekend along with the steering cable. The boat needs to be completely re-wired as far as any accessories go. Hopefully, I'll get the choke working again and that will get her starting cold. I really appreciate all the help.

the 3 prong connector on the front of controls is for a tach if look where manual choke is connected youll see a solenoid with a plunger sometimes the plastic linkage breaks if thats intact verify voltage at choke solenoid if there is no voltage youll have to open controls those old mercs are notorius for corroded wires the incoming power is a white wire on key switch which goes to choke switch the grey off choke switch goes to the choke solenoid my advice is to get a seloc manual before tearing controls apart there could be wires in ther ready to break or with no insulation but definately sound like choke is not working that solenoid is really loud youll hear it clunk

 

[Bronkitis]

Re: Tower Of Power -Let's talk plugs!

Ok guys! I got the choke to work! S.Hadley81 was right on the corroded wires. I replaced all of them that I could fine; the RIGHT way! Previous owner thought electrical tape was enough... Enough to hide it I suppose lol! Anyway, the choke is working and with full throttle and full choke, it popped off about after about 3 minutes total of cranking which is still way too long... I pulled plugs and cleaned, they look good. I replaced all corroded wires after several trips to store, pumped bulb as hard as possible and still, she is just a bear to wake up. Where should I go from here? I'd like to have it water ready by next month. Please help!

Also, it seems as if the pee stream is a little weak. This being my first large outboard, I guess I'm not too sure what exactly it should look like but it seems that my Nissan 9.8 has a stronger stream. Just looking for thoughts. I'll probably replace anyway; what's the harm?

Thanks again everyone.

p.s. My choke solenoid is very quiet. The only thing I hear is the manual knob bumping around. Thought that was interesting.

 

[Texasmark]

Re: Tower Of Power -Let's talk plugs!

Ok guys! I got the choke to work! S.Hadley81 was right on the corroded wires. I replaced all of them that I could fine; the RIGHT way! Previous owner thought electrical tape was enough... Enough to hide it I suppose lol! Anyway, the choke is working and with full throttle and full choke, it popped off about after about 3 minutes total of cranking which is still way too long... I pulled plugs and cleaned, they look good. I replaced all corroded wires after several trips to store, pumped bulb as hard as possible and still, she is just a bear to wake up. Where should I go from here? I'd like to have it water ready by next month. Please help!

Also, it seems as if the pee stream is a little weak. This being my first large outboard, I guess I'm not too sure what exactly it should look like but it seems that my Nissan 9.8 has a stronger stream. Just looking for thoughts. I'll probably replace anyway; what's the harm?

Thanks again everyone.

p.s. My choke solenoid is very quiet. The only thing I hear is the manual knob bumping around. Thought that was interesting.

At idle, if it will shoot 2" below the surface you should be good to go.

 

[Bronkitis]

Re: Tower Of Power -Let's talk plugs!

Yeah, I don't forsee that happening so looks like I'll be doing that sooner than later. I've yet to take the boat out on the water due to bad steering cables so I can't be sure but I am almost positive it won't "shoot" 2" into the water. Thanks for the tip though!

Any idea's on how to get the bugger starting nice and easy?