Ec25ds Video of backfiring no power need ignition info

[Thimmesch1]

engine:Ec25da 244 robin fuji serial # 121556
symptoms:backfiring through exhaust,black plug,will drive around spitting sputtering & backfiring choking it momentary helps very little.
125 psi & spark in forward & Rev, new plug, new fuel filter, new fuel pump, new non stock coil,new gas at 1.5 oz per gallon


things I have tried:(through reserch of this site) alot of knowledgable people!!

I used carb cleaner to try to get it to rev up & it does not,whether I spray it in the carb or around both seals.

I loosened the muffler,No need for a BBQ.

I tried to get it running w propane in the intake(no change)

does this engine have points?
I have the fan cover off & the fan will not come off without a puller.
there are 2 metal boxes on the fiewall smaller one with a yellow wire that goes to the coil & a black & red one that goes to the relay,Is that the pulsar?
Is that what should be between 75-150 ohms.
The bigger box says nipendenso?
What & how can I test electrical components.or any other suggestions would be appriciated.vdeo of it not running right

YouTube- MOV00081

YouTube- MOV00081

this is floored with a quick choke pull
Thanks

[mb523]

Hello again! Do you have a new plug/filters in it? This sounds like the engine is missing like it isn't getting enough fuel. Usually if pulling the choke brings up the RPM's a bit the cause is a blocked up main jet. The main jet is in the carb bowl bolt. Use some carb cleaner and a small wire to ensure all the passages in the jet are clear. It is very possible there is some varnish blocking it up a bit.

As far as the ignition system... there are points and a condenser under the flywheel. The small metal box is a blocking relay that prevents you from shifting the cart into reverse while driving in forward (and causing major electrical damage to the starter). The larger box is the voltage regulator for charging the battery while the engine is running.

Another idea would be to ensure you are getting a consistent bright blue spark. Remove the plug, ground it, and turn the engine over. Watch for spark every compression stroke, make sure it is bright blue. Otherwise you should troubleshoot the ignition system. It sounds like your seals are not the problem so it is either fuel delivery or ignition.

Give these things a go and let us know what you find.

[Thimmesch1]

Yea ,new plug & fuel filter.I turned it over with the ignition & seen a good blue spark-I will try turning it by hand.
I already cleaned the carb but I am going to clean it again.
It seems that it is going to take off fine then when swithing to main jet it falls on its face then starts over in that cycle?
Thanks

[Thimmesch1]

When I have the rear tires off the ground have it floored & spray carb cleaner in the carb shouldnt it rev up? It does not rev up.
Doesn't that rule out the main jet? (I also tried propane)
Thanks

[Thimmesch1]

cleaned the carb-main jet is clear.
cleaned the points-they looked good.
still no improvement.
Thanks

[DEWDIGGLER]

(1)try pulling the gas line out of the tank and clear it or replace.
Or better yet replace from the bottom of your tank to the carb.

(2)the timing could be off? ( not likly if you havent pulled the fan shroud)

[DEWDIGGLER]

PULL THE FUEL LINE AT THE CARB AND TURN IT OVER TO SEE HOW MUCH GAS SQUIRTS THRU YOUR PUMP.

TAKE THE THROTTLE CABLE OF THE CARB AND MANUALLY RUN IT.
MAKE SURE THAT THE ADJUST SCREW ALLOWS IT TO SHUT ALL THE WAY.

GOOD LUCK, DEW

P.S. ITS PROBLY SUMTHG SMPLE
WERE FIG IT OUT

[Thimmesch1]

this thing has me stumped,I can usually get an engine running right in short order!! Observations & questions
1. revs up only slightly when choked or spraying a gas mixture into the carb, which could be fuel delivery or a cobination of fuel & ignition?
2.fuel pump is pumping enough fuel to carb,which tells me if it is in the fuel system it is in the carb.(which I have cleaned twice)anyone know what main jet size this engine takes?(there was a bag with my parts that said"5 jet set" no extras were included)
3.current plug is b8es is that correct?
4.I found what looked like a bad ground for the engine & replaced the plug & with it in nuetral ,with the solinoid on & turning the cranckshaft to check for spark I noticed that about 2 out of 3 sparks were more white & the third a nice blue spark(new Plug) which would indicate an ignition problem. I had the fan wheel off & cleaned the points & blew out the generator/starter.
seeing I have never seen this machine run.I never researched timing? although that is a very good lead?
Thanks

[DEWDIGGLER]

try a new condenser.
after watching the video, that sounds just like the problem i had
reset your points between .013 to .015, (or a match book cover)

good luck, Dew

[DEWDIGGLER]

make sure to reset your points at the highest point on the cam.
(this is much easier to do with the engine out)