Timing Procedure

[trashy]

This might seem like a silly question, but here it goes.

While setting the timing on a 1997 Merc 150 EFI, the book (Mercury shop manual) says to remove all the plugs except for #1. It doesn't say anywhere anything about grounding the plug leads that are disconnected. I understand the concept about discharging the voltage developed in the coils somehow, and I was trying to figure out a safe way of doing this. Is there some sort of "trick of the trade" that you guys do?

Also, on the same subject. Could I not just ground the low side of the coil (the green wires from the switch boxes) and achieve the same thing?

[The Big Al]

You remove the plugs to prevent the engine from running.

It understood by the technician to use the plug isolator tool.

http://img520.imageshack.us/img520/5946/sparkpluggapboardxf9.jpg (http://imageshack.us)

You can install the plugs into the plug wires and ground them and get the same thing.

[trashy]

Thanks for the reply Al. I just looked it up on Parts Express. $79.27! :eek:

I'll bet I can make something that works the same way.

[The Big Al]

Do not ground the plug wires shorting out the ignition.

You want the plugs to be base grounded to let the plugs fire.

[shooter1]

Make sure that the plugs are away from the spark plug holes because the air coming out of the spark plug hole is charged with gas and is flammable. Sometimes money is cheaper than 911 or an emergency room visit.

Shooter1

[T-REX]

This iz politikly incorrect, and very unprofessional, but it'z way tha hell cheeper than $80........U kan also use it to check ignition fire...gap tha plugs az wide az ya kan, and it will sho U a week coil or problem...

6 used plugs, a foot ov 1 1/2 X 1 1/2 aluminium angle, drill 6 holes and tap to screw in tha plugs, and WHALA....U saved yaself $80 and earned tha rite to be called a cheepo, junkyard dog like ME!!!:D

[Scott in MN]

Hey Rex, that looks easier than the mess of wire that I wrap around the plug threads and ground to the block....I'm goin to make one today...Thanks

[The Big Al]

T-Rex to the rescue!

I making mine!

[trashy]

This iz politikly incorrect, and very unprofessional, but it'z way tha hell cheeper than $80........U kan also use it to check ignition fire...gap tha plugs az wide az ya kan, and it will sho U a week coil or problem...

6 used plugs, a foot ov 1 1/2 X 1 1/2 aluminium angle, drill 6 holes and tap to screw in tha plugs, and WHALA....U saved yaself $80 and earned tha rite to be called a cheepo, junkyard dog like ME!!!:D
I guess in some ways I'm a cheepo junkyard dog.;)

I made one similar to the one that Al posted. I used a piece of board, 6 metal clamps like what is used to hang tools, some wire and connectors. I also used an old clamp and wire from a battery charger. I just finished testing it out, and it works great. I'll try to post some pics later when I get the digital camera back.

[trashy]

Make sure that the plugs are away from the spark plug holes because the air coming out of the spark plug hole is charged with gas and is flammable. Sometimes money is cheaper than 911 or an emergency room visit.

Shooter1
That was my concern when I said initially that I was looking for a safe way to do this. What I made basically cost me nothing since I used stuff I had laying around my shop.;)

[j_martin]

Now all T-rex has to do is learn to focus the camera.

I spun the nut off the top of 6 plugs, found some metric screws that fit them, put a wire and aligator clip on each, and I can stuff them into the plug wire boots and clip the other end onto anything grounded, or my kid if he needs an adjustment.

John

[bigbore]

All you gotta do is pull the kill switch.:cool: Thinking mercs got one 2,but o.m.c.'s are on the control box.

[Riverman]

All you gotta do is pull the kill switch.:cool: Thinking mercs got one 2,but o.m.c.'s are on the control box.Timing light won't work then. :)

[T-REX]

Timing light won't work then.



Good catch;) ......gotta have a lil spart to set time'in!!

[j_martin]

All you gotta do is pull the kill switch.:cool: Thinking mercs got one 2,but o.m.c.'s are on the control box.

And then if a harness connection or switch or whatever fails, you pay for it with your toes.

John