View Full Version : Electric Choke
04-25-2005, 09:11 AM
How long does it/ should it take for the electric choke to "pull in" on a cold start situation?
To make a long story shorter, my fast idle cam broke off so I'd been cold starting my motor using a piece of coat hanger to hold the plate open - worked great, but....anyway that's replaced now,but the other morning when I launched (finally) I had to grind and grind before the thing would start...so I got to looking around. The next morning, I watched the electric choke SLOWLY pull open, like 1 to 2 mins. - good news is, once the choke does its job, the motor starts...
So is mine old and slow (my wife would say I might be, she doesn't know much about chokes) or is this normal?
04-25-2005, 09:14 AM
I thought that was roughly how long mine took. I just rebuilt it and have only had a chance to run it in the driveway, but I think that sounds about right, give or take.
04-25-2005, 10:04 AM
I had a similar problem but mine was taking much longer than 1 - 2 minutes. I bought a new choke cover and coil from Discount Inboard Marine and installed it and now it opens much quicker. These things don't move immediately from my experience but they can start getting much slower and quit working all together with some age on them.
04-25-2005, 10:09 AM
:twocents: Wes, yours has a different carb than my original carb (4160) but mine engaged quite quickly, maybe 30 seconds or less. Something doesn't seem right on your carb
04-25-2005, 10:32 AM
I assume mine's the original to my boat - 4150 dual pump, so yeah, she's got some age on 'er....
Here's my carb...
I may re-wire it as I think wen I was watching I was giggling wires and maybe that seemed to "help"...then again, if conventional wisdom says replace it, then I'll do that...I'm just trying to get a concensus...
Oh yeah, the piece of coat hanger in that pic is my "cold start" feature which hopefully won't be necessary.
04-25-2005, 02:29 PM
So I was actually thinking about electric chokes this weekend and have a few questions (and hopefully won't hijack this thread too badly...) about how they work.
With older mechanical chokes on the cars I've driven you punch the pedal to the floor to set the choke and then start the car. It'll idle fast and then after it's warmed up you'd hit the pedal again to kick off the choke.
With my boat and electric choke I have no clue what it's doing. I just give it a couple of pumps of the throttle (usually about 1/2 throttle or so) and fire it up. It usually catchs right away, but will run 'lumpy' for the first 30 seconds or so and I have to keep it at 1500 rpms or so for the first minute or it will stall. My parent's boat is the same way (350 Merc I/O), but runs smooth initially.
How do I tell if the choke is operating properly? Should I be able to tell if it's working or not? Is my initial lumpiness a result of the choke?
04-25-2005, 02:58 PM
The chokes on most marine carbs work a little differently than an auto choke. Most of them will not have the fast idle cam connected. I recently talked with Holley about this as I was rebuilding a 4160 and noticed that it did not have the fast idle mechanism and I thought I needed it for the choke to work properly. Essentially what Holley told me was that they don't recommend the fast idle set-up for marine applications because it's not really necessary and could be dangerous. The reason is that boats have a 'sticky throttle' meaning that it will stay where you put it whereas a car's throttle will always close right back to the stops when you take your foot off the gas. So a marine choke will have the choke plate that closes when the engine (or the choke thermostat) is cold which creates a richer mixture and helps the engine run when cold. This plate will then open gradually as the engine warms. The operator creates the fast idle by simply placing the throttle where they want it. If the fast idle cam was used then the engine would not come down to idle speed when the throttle was pulled all the way back and you would probably see lots of people ramming docks, other boats, trailers etc. It would also be hard on the transmission to engage at a higher RPM.
If you have an electric choke you can test it simply be looking at it when you first turn the key on. The plate should be closed. Many chokes do not rely on engine temperature to start opening, they have a simple bi-metal thermostat device that heats up and causes the plate to open regardless of what the motor is doing, even if it isn't running. The electric choke on the 4160 works this way. You can watch it open if you turn the key on and wait. You can adjust how long it takes to open by turning the cover one way or the other.
That's about all I know about chokes on boats. Not sure if that helps or not.
04-25-2005, 03:40 PM
Makes sense to me... Now I'll have to go look after I get the boat unwrapped.
04-25-2005, 04:07 PM
Seems like 1-2 minutes may be a little long, but as some said it will usually take atleast 30 seconds to fully open.