checking for spark
#1
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From: marion,
IL
i just got a new motor a few days and i can't get it to fire i know its getting fuel and compression i don't think i'm getting any spark i did a spark test like i would have on a small block chevy so i was wondering if i was doing it right or is there a spiecal way to do it with rc gasser motors
#2

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From: Summerfield,
NC
ORIGINAL: armyguy466
i just got a new motor a few days and i can't get it to fire i know its getting fuel and compression i don't think i'm getting any spark i did a spark test like i would have on a small block chevy so i was wondering if i was doing it right or is there a spiecal way to do it with rc gasser motors
i just got a new motor a few days and i can't get it to fire i know its getting fuel and compression i don't think i'm getting any spark i did a spark test like i would have on a small block chevy so i was wondering if i was doing it right or is there a spiecal way to do it with rc gasser motors
#3
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From: Rising Sun,
MD
When checking the spark make sure you have a known good plug in the socket. You don't have to ground it to the engine because stainless braid on the plug wire is your return ground. Just make sure the plug is in the socket and there is a good tight connection to the plug base. Some ignition boxes will be damaged if the engine is turned over with no plug in the socket.
#5
It is the same as the Chevy.
Some marginal sparks jump at atmospheric pressure, but not inside the chamber, under pressure.
This will tell you what is happening inside:
http://www.harborfreight.com/inline-...cker-4424.html
Some marginal sparks jump at atmospheric pressure, but not inside the chamber, under pressure.
This will tell you what is happening inside:
http://www.harborfreight.com/inline-...cker-4424.html
#7
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From: marion,
IL
here whats going on i got my volt meter and checked it i'm getting power from my battery and when i turn on the switch to the ignintion the plug sparks but when i turn the crank i get no spark
#8
Hi Armyguy
You might want to check the connection between the sensor pick-up and the ignition module. There could be a loose wire or poor contact between the individual pins. Also check the area underneath the senor to see if maybe they forgot to install the triggering magnet. You can test the sensor with a bar magnet too to make sure the sensor is working. The sensor is a hall effect unit that needs the correct pole of the magnet to trigger it. It could be the magnet is mounted backwards and is not presenting the correct pole to the hall effect sensor.
If you are getting spark when you turn on the system chances are the ignition module is okay. The ignition sensor is not triggering the system and could be just bad...
Hope this helps
Carlos G.
You might want to check the connection between the sensor pick-up and the ignition module. There could be a loose wire or poor contact between the individual pins. Also check the area underneath the senor to see if maybe they forgot to install the triggering magnet. You can test the sensor with a bar magnet too to make sure the sensor is working. The sensor is a hall effect unit that needs the correct pole of the magnet to trigger it. It could be the magnet is mounted backwards and is not presenting the correct pole to the hall effect sensor.
If you are getting spark when you turn on the system chances are the ignition module is okay. The ignition sensor is not triggering the system and could be just bad...
Hope this helps
Carlos G.
#9
If the ignition module looks like the two in the first picture it is not worth wasting time on they are famous for being worthless right out of the box, replace it with an Rcexl ignition module and sensor. If it looks like the one in the second picture with the engine, you can use the Rcexl throubleshooting guide I wrote here http://www.rcuniverse.com/forum/fb.asp?m=10187833
The second version ignition is better but the plug cap could be much better, again an Rcexl replacement would be a big improvement. Also check that the gap between the sensor and magnet isn't to wide, about 1mm or less is prefered.
The second version ignition is better but the plug cap could be much better, again an Rcexl replacement would be a big improvement. Also check that the gap between the sensor and magnet isn't to wide, about 1mm or less is prefered.
#10

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From: La Porte,
IN
ORIGINAL: jedijody
.......................you can use the Rcexl throubleshooting guide I wrote here, http://www.rcuniverse.com/forum/fb.asp?m=10187833
...........
.......................you can use the Rcexl throubleshooting guide I wrote here, http://www.rcuniverse.com/forum/fb.asp?m=10187833
...........
Maybe a forum glitch?
http://www.rcuniverse.com/forum/fb.asp?m=10187833
But this one does......how odd.
EDIT: It does now that w8ye fixed it.
.
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From: Billingsley, AL
I bought one of those Rcexl testing kits. Works great. It is possible to test the pickup and the ignition seperately and set the timing without the ignition hooked up. Just remember the plug fires when the LED goes off.
#13

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I remember my dad trying to pull that on me when I was a kid and I wouldn't do it. So he held the plug while I turned the engine over. He said; "Yes it had spark but it was weak" I didn't see any physical reaction from him as he didn't light up or anything.
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From: La Porte,
IN
Try that with an Accel or MSD coil and they will react!!!!
I worked with a country type fellow that would hold a plug wire then put his ear next to the hood for the spark to jump off of.
I worked with a country type fellow that would hold a plug wire then put his ear next to the hood for the spark to jump off of.
#16
My dad used to charge capacitors and throw them across the room to you, your instinctive reaction is to catch....ouch!<div>We had an electric fence on the farm when I was a kid, I could hold onto the wire and act like it was didn't work, got my dad back a few times for tossing capacitors at me.</div>
#17

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My dad used to check for spark by pulling plug wires bare handed. When he would get zapped, he would barely flinch and say "Oh, that one bites a bit..." I am much more sensitive to shocks, and have been blown right out from under the hood a few times when zapped! All in all not a recommended way to check for spark...
One time I was trouble shooting my nephew's motorcycle and he kicked it over hard while I had ahold of the spark plug wire. Man, I chased that little sh-t around the house three times till I tired out, with him laughing the whole time. That was 25 years ago and he still talks about it.
AV8TOR
One time I was trouble shooting my nephew's motorcycle and he kicked it over hard while I had ahold of the spark plug wire. Man, I chased that little sh-t around the house three times till I tired out, with him laughing the whole time. That was 25 years ago and he still talks about it.
AV8TOR
#18
My grandpa was a good conductor but not a ground I guess.. He would grab a plug wire then stick his finger close to arc on to your ear lobe when you were not paying attention.. Also did the charged condenser trick as well...
Rick
Rick
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From: stony point, NY
my brother got his elbow up against a modern mercury out-board mnotor sparkplug lead,,,,he flew into the water. had hios right arm in a sling for several weeks. these super ignitions arent my stock nail head buick that i have in the duece,,,hehe
#20
My Nephews used to monkey around with stuff I had setting on my work bench. I charged a few capacitors up real good and left them there to grab. Well I guess you know...they learned not to monkey with my parts on the work bench anymore!!!
Capt,n
Capt,n
#21
Can you use one of the old capacitive (Iinductive?) Sears timing light to check for spark on a magneto equipped engine? This would entail having to put a short length of unshielded sparkplug wire in the line for the pickup to sense from? Will the timing light flash when the mag produces a spark? Should either the plus or minus side of the 12 volt battery that is needed to power the timing light be connected to the engine housing? Thanks.
Richard
Richard
#25
My grandfather wired a Ford vibrating spark coil to a metal lamppost that the town drunk used to piss on every Saturday night, until................he lit up one night after the coil was turned on****************.
A friend used a Ford coil tied to his 49 Mercury chopped and channeled chassis. If someone leaned on the car, he turned the coil on after dropping a chain through the floor to complete the circuit.***********************************
A Ford coil was used to fire sparkplugs in the exhaust pipes that went up just behind the cab of another friends pickup. The sky lit up when they were fired.***************(probably not enough unburned fuel in today's cars to do the same, but i would lke to try
)
Richard
A friend used a Ford coil tied to his 49 Mercury chopped and channeled chassis. If someone leaned on the car, he turned the coil on after dropping a chain through the floor to complete the circuit.***********************************
A Ford coil was used to fire sparkplugs in the exhaust pipes that went up just behind the cab of another friends pickup. The sky lit up when they were fired.***************(probably not enough unburned fuel in today's cars to do the same, but i would lke to try
)Richard



