Mercruiser 470 backfiring

[shane_kroesen]

"my mercruiser 470 pops out of

"my mercruiser 470 pops out of the carby, some times after 30min, some times after 90 mins of running, it only pops a few times and then stops and then it might do it in 5-10 min time i have change all the fuel filters, also when it dose this or just before or after the tacho needel flicks alot i am realy not sure"

 

[kevin8or]

Hey there Shane

Most likely

Hey there Shane

Most likely you need to change the the Distributor Cap. I have had the same problem before and after days of trying to fig it out I change the Distributor Cap and all was good.

 

[jw_in_dixie]

Next time it does this look at

Next time it does this look at the voltmeter. High voltage (16+) will cause cross-firing. Been there and done that. V reg was shot. JW in Dixie

 

[scott_s]

disconnect the tach lead and r

disconnect the tach lead and retest