Briggs Engine Backfire

HighTide

HighTide

New member
Recently bought and installed a second PW (coldwater) and have run it for 40 hours already. Like my main skid, it is also a Vanguard 18 hp. I have run my main unit now for 3 1/2 years and it has maybe backfired 3 or 4 times total that I can remember. My new one backfires 2 or 3 times a day but performs perfectly while running. The new one has a throttle on it and the old one does not -- does that make a difference? I have not used my throttle on my new unit yet as left in full throttle keeps it running right at 3400 rpm on my TinyTach. The majority of the time, my new unit will backfire approximately 5 seconds after engine is shut off. Is there some sort of adjustment I need to make and is this bad for the engine or muffler? Thanks for any advice as I am tired of alarming the neighbors with a gunshot like pop!
 
It really doesn't hurt much, more of an annoyance. Slowing the throttle before shutting it of may help, or you can get the anti-backfire solenoid and install it on the carb.
 
Thanks all. Idling down did help the last two days as it backfired only 50% of the time after shutoff and it was not quite as loud. Although it did backfire a couple of times today while I was idling down.
 
Try idling down to turtle setting run for 30 to 60 seconds then speed it up quickly to just under half throttle and turn the ignition key immediately off during increase. (use both hands, one on throttle and other on key switch)
 
Last edited:
I never run my Vanguard 18HP at the full 3400 RPMs. Normally I keep it at around 3100 or so. Just like my TS2021 I have it set to run at about 3200 PSI and not the full 3500. Less wear and tear on equipment, no loss in performance on the equipment.
 
For all of you guys installing new drivers, pumps or entire units consider over sizing engines and pumps, besides the fuel savings, think longevity, noise etc.

Think 2800 to 3000 rpm on gas small driver engine and if possible hit under 1250 rpm on pumps do the calculations and figure your output. If you have the budget go diesel and industrial pumps<O:p</O:p
 
Vince Wood said:
I never run my Vanguard 18HP at the full 3400 RPMs. Normally I keep it at around 3100 or so. Just like my TS2021 I have it set to run at about 3200 PSI and not the full 3500. Less wear and tear on equipment, no loss in performance on the equipment.
Click to expand...

Air cooled engines are designed to run wide open. Lower your rpm's with pulleys, not with the throttle.
 
Nigel, running at a lower rpm is fine for cold water and hot water machines with 120 volt burners and generators, as long as it's pulleyed properly for correct generator rpms. On hot water, 12 volt systems, the engine has to spin at it's rated operating rpm for correct alternator output.
 
Russ Johnson said:
Nigel, running at a lower rpm is fine for cold water and hot water machines with 120 volt burners and generators, as long as it's pulleyed properly for correct generator rpms. On hot water, 12 volt systems, the engine has to spin at it's rated operating rpm for correct alternator output.
Click to expand...


True Russ J, I remember you telling me this, I never owned 12V, and yes you would want to run at an rpm to generate the correct voltage, for the 120V you can size the pulleys, sorry 12V guys
 
810f250 said:
True Russ J, I remember you telling me this, I never owned 12V, and yes you would want to run at an rpm to generate the correct voltage, for the 120V you can size the pulleys, sorry 12V guys
Click to expand...

Nigel where have you been?
 
You must log in or register to reply here.
Back
Top