Duromax 440cc $263 shipped

20% off coupon in description cheaper and bigger than 420 predator. 1/2 price of a Honda 390. extra 50cc will turn pump easier.

video is a build, but you can see the internals simple engines.


30 horse seems kind of low for built 440 :thinking:

I dont see a dyno, so its all guessing hp. Torque is more important for pressure washing and other tools i use.

But 440 cc for $263 delivered…should have more grunt @3600.

I bought the electric start 18hp Duromax for our golf cart. It’ll do about 30 mph. I didn’t end up using the Duromax starter in the build so still have all of that stuff. At that price I wouldn’t mind picking one up for my log splitter. Since I already have the electric start components I could turn my splitter into electric start. Where did you see the 20% off coupon @Mustang? I’m not seeing it unless I missed the sale.

Type. RBG in coupon code
20% off

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That did the trick. Thanks!

your welcome.
I have 1 coming too. when I get to it, ill comment on it. I got 2 places I could use it…
I got a honda 390 that is giving me a headache…bought a 13 hp leaf blower…It will idle but not rpm.
I fixed the carb, and nasty tank,lashed the valves that where way out, even changed the blown head gasket…still wont rpm.
down to either a bad cam or maybe the flywheel moved and its not on time.

working on a portable 12v cart set up…

Sounds like a carb issue, what did you do to the carb to fix it

cleaned the carb. no improve.
new carb. no improve.
new aircleaner. new plug. new filter in tank.

interestingly, new coil-no start. put old coil back on, start immediately

engine shakes violently when given throttle.


@Mustang I know this sounds simple but did you replace fuel line when you did all this. Also take the kill switch out and wire it straight I have seen them do exactly what you are describing turned out to be one of those things I felt really dumb when I figured it out

did not replace the fuel line. ok…can do that, but i get plenty of fuel flow.

kill switch…you mean on off switch or low oil switch?
that would just kill spark…right?

If the switch is going bad it could interrupt spark just enough it’s worth a try. What voltage do you get st the plug wire

dont know…I never measured that…nor have I ever.

what had me confused is I put a new coil in, and I couldnt get it to start. put old one in…boom started.

wonder why…I just figured it was defective.

Could be. Could be a bad wire loose connection. When you say you fixed the carb

ok…ill swap the new coil back in tomorrow…and change the switch.

99% it isnt the carb…i tried a new one, no different. I am real good with those carbs…but im second guessing everything now. i bought a kit for 34 bux…glad it had a head gasket in there…that was toast!

when I first got it, was very hard to pull…adjusted valves and it pulled normal again. Just will not RPM when i give it throttle. shakes violently.

It seems like its off time to me…or the cam is worn out. I measured the lift at valves…I measure 0.357 lift on both intake and exhaust.

My guess is it’s a spark issue then you got a bad wire

Bypassed oil sender. direct wire no difference.

today it kicked backed Hard while pulling it. rechecked valve lash, its right on the money

I am betting the cam/decompression…going to put it aside for a while. spent way too much time on it last 2 weeks.

I ordered that Duromax for my wood splitter last weekend and it got delivered on Thursday…lol. The box wasn’t in bad shape at all so I’m not so sure how it was damaged so bad. I emailed pictures and got a pretty quick reply from a different department wanting the pictures. I’m expecting a reply on Monday. I’m sure they’ll just send another one. Their customer service is pretty good. I threw a rod in one on the golf cart. It was still under the 3 year warranty so they sent a new one no questions asked. I just had to pay like $50 for shipping. Can’t beat that. I ran the heck out of that thing for just under 3 years. The warranty was a week away from expiring too.

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Wow! I’m sure they’ll make it right. Makes you think how it got that way though…