puzzled. engine backfired

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
nightwolf24

nightwolf24

Active Member
Messages
37
Reaction score
0
Location
uk.staffordshire
hi all havnt been on a while with working alot so i took my mutilator out last week was working fine and then my main gear came off so went home to find my spare. turned out the gear that came off was sitting in side on my chassie put it back on used some metal glue to stop it from coming off again went to start it, an there was a loud bang sounded like something hit the fence hard and cant get it running. spark plug is always wet si presumed it was flooded so i drained it left it a few hours and still not even a pop, these are sopposed to be easy to use they baffle me can any 1 help.
 
Check your spark. You may have a cracked interanal plug rod. SOunds like its building up fuel then spark and bang. I never had it happen.
 
ok ile check my coil and spark it wont run with a standard plug in it will however run with a iridium plug in well it did ive got loads of the the standard crc7h or whatever lol
 
pull you pipe/muffle off and check if its full of any fluid or foreign material, sounds allot like an issue I cam accross in the past, turned out the muffler got full of fuel and was affecting in, cleaned that out and all good again.
 
You plug is fouled... Put a new plug in it and you should be good to go.

Make sure you retune the carb as it sounds that you have it too rich. Once a plug is fouled, it's always fouled. Toss it in the bin and buy another...

This is what caused your "Pop"...
When the muffler gets unburnt fuel in it, it can be lit by the spark when you are pulling the recoil. It happens, but it's caused by the excess fuel. It doesn't usually happen when the motor is hot because the fuel is being burned by the high temp of the exhaust. When the motor is allowed to sit, the exhaust cools and allows the unburnt fuel to pool. One good spark and poof! Lean your carb so this doesn't happen again.

BTB... What is, "A cracked interanal plug rod." ...Are you talking about the center electrode? Anything like a Johnson Rod?

Wolf, just throw in a cheap plug, (The iridium plug isn't necessary, considering you have a stock can) The slight amount of performance gain the plug can offer is smothered and choked by your restrictive muffler.

Re-adjust the carb so it isn't so rich and take it out to a field and beat the snot out of it to get all the goopy unburnt oil out of the exhaust...

Mix your next batch of fuel at 32:1 or 40:1, I have mentioned this before. The recommend oil mix it too much damn oil... To put it in comparison, I run 100:1 Amsoil synthetic for years and I never have experienced a problem. I wouldn't recommend you to do that, but 40:1 would be about right for you. No more oil slop dumping out of the exhaust and no more oil stink belching out of it when you have it stored. I store my trucks inside and I can't stand that stink!

Your coil is fine, your Johnson Rod is fine too. It just needs a plug and a retune.

Trip..
 
Back
Top