MK 78E Remote Control Box

[dannynagasaki]

Hello Everyone,

I'm trying to get a better understanding of how the MK78 Remote control works.

1) According to the manual, the electric choke is supposed to be activated by pulling back on the button as you press down.
I don't see how when I remove the cover off & inspect in the control box that the choke is activated. Is it an electrical circuit inside of the handle that touches when you pull back on the button as you press down? Does it somehow make an electrical connection that you cannot see by pulling back on the button? There is no electrical wiring anywhere that I can see, just the plunger pushing straight down.

2) About lubricating the rack inside the box. Suggestions for the type of lube or would lithium be a safe choice?

3) In the manual on pg. 35 section 7 in the 1965 & Prior manual, the wiring diagram notes "jumper" next to the black & blue wires. Just want to confirm. Does this mean short pieces that lead from the terminals of the switches where those wires are supposed to be connected are to continue to the terminals on the pilot light? (wiring isn't a strong point for me)

4) On pg. 35 section 7 in the 1965 & Prior manual, there is a notation at the bottom of the page that reads " Blue jumper in control housing only on controls with choke button in handle".
Again, I think I have the electric choke button on mine as the button on the top of the handle does have room to pull back to activate. I just don't see any wiring for it in my control box, just the plunger that presses down on the toggles to activate or press the forward & reverse buttons. Should I be seeing wiring for the electric choke? How is the electric choke activated?

Any help with this would be much appreciated. Thanks

[Arlie]

The electric choke is in the key switch on these cotrols, it has off on and choke positions and of course the button on top the throttle lever actuates the swithes inside the box for starting.

[mercaholic]

Danny, let me know if you need any controllers or parts.

I have a box of them.

[dave bernard]

i have a dwell plate if someone needs.

[Conrad]

Danny,

Does your key switch spring past ON? Like it would if you started it from the key? If you have OFF/ON and SPRING ON on your key switch your choke is that springy part in the key switch. I think the Button on the handle is only for starting.

DID the MK 78E have a white box or id they use the Black box like the old MK 75 and mk 78???? If its like the old MK 75 and 78 boxes the choke is def in the key switch. and start is on the handle.

Conrad

[LarryR]

white boxes do merc600.700.800, six pin Cobra, FWD/REV switches mounted on distributor drive.
green and black boxes do mark75,75A,78,78A, seven pin Cobra, FWD/REV switch in the controls

[dannynagasaki]

I have a '58 wrinkled finish charcoal black control box. The key switch has three positions but the third does not have a spring in it.
Would that indicate any setting other than the choke on the third or perhaps the spring part is pooched on mine.

I'm still wondering what this means :
On pg. 35 section 7 in the 1965 & Prior manual, there is a notation at the bottom of the page that reads " Blue jumper in control housing only on controls with choke button in handle".

The only setting on the push button in the handle appears to be straight down to push the toggles against the forward & reverse buttons.
Pulling back the button doesn't do anything. I'm guessing like you said Conrad, the choke must be the third key setting.

That would mean that when you start a cold motor, you would have to hold the key to the third position with one hand while pushing the button down with the handle pushed forward in the forward position & turn the key back once it fires up.
it's not a biggy to multi-task but was this the way it was designed to start??

It would be easier to start it with one hand as per instructions.
Press down to start while sliding back the button to choke at the same time & then slide button back forward once it fires up all in one motion.

[Conrad]

Danny, If you look at that page your talking about youll see the wiring diagram for the key switch. It shows for the key switch 3 positions OFF IGN and CHOKE. IM 99 percent sure my mk 75 controlls use the switch for choke. Try squirting some wd40 in the switch to see if it might loosen it up so a spring might work in there, might just be sticky enough not to spring back or broke. If your controls are still wired up hook it up to a battery and kick the key switch over to the 3rd position(choke) and take a meter and check (C) hole on the end of the wire harness to see if you have current showing up when you switch the choke (refer to the next page pg. 36 sec 7 to see the lt blue wire)

Im not 100 percent sure what that statement on the bottom of page 35 means. It is possible that the real early sets tried to use some sort of choke function in the pistol grip. If I remember correctly one of my pistol grips might be a bit different but I still think all of them operate the choke VIA the key switch.

And yes two hands are better than one when starting and choking one of these.

My dockbuster is 35 miles away in storage, so its hard to remember, I only got it out once last year.

Conrad

[John McIntosh]

The first pistol grip boxes that came with the Mark 75 and 78 were quicksilver green, you turned the key to what is normally the crank position for choke. The boxes that came with the 75A and The 78A in 59 were crinkle black. You could either turn the key to what is normally the crank position,,, OR depress the starter button further WHILE cranking in fwd or rev to choke. Not many people realsed this because once the motor was cranking they saw no reason to push the button down further. Check out the wire diagrams...75 and 78 box...no blue wire to the switches,,,,75A and 78A box....blue wire to each switch. Now Im not saying that yours will work....Im saying that it did work back in the day....

[John McIntosh]

Im sorry,, the more I think about it the more unsure I am....I know the first 1957 75s didnt have the pilot light and you turned the key to choke it. BUT did the 1958 75 and 78 have a green or black box? and did the 1958 75 and 78 box irreguardless of its color have the choke in the switches feature???or did that not come till 59. And how many 57s and 58s are running around with 59 boxes?? To see if your box has the choke in the starter button feature you will have to open it up and look at the wires going to the switchs...is there a blue to both switches??? or just yellow and black to one and green and black to the other??