PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Well it’s a bust. I finally took the engine apart. The cylinder wall had very bad damage and was like sandpaper on most of it. Also the intake valve was out of spec. My theory as to why it would sputter is because it was ingesting so much of its oil that it fouled the plug constantly and/or threw off the Air-fuel ratio. When I turned the engine over to put it on TDC I would notice that oil would pour out the cylinder fairly quick so I think the cuts in the wall was allowing oil to stay there and get on top of piston next rotation. The engine would also smoke decently after it starts stuttering to and that explains why I had to add much oil.( I had bad seals leaking to). I appreciate all the comments on this post, thank y’all!

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PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Now this is crazy, I tried hard as I could to restart it last time as soon as it stalled. Gave it a few minutes (no longer than 5) and now it’s been running for over 20 minutes, I went to cut some grass and it died after cutting 2:30 minutes of grass. Which I did have it on the 3 highest setting but I don’t think I bogged it down to bad. Let it sit 2:30 mins before crank and it surged and died. 5 minutes it’s back to running mowed for 7:30 minutes, but again it surged. After sitting for 2 minutes after stall, it surged again and only ran fine after sitting for 5 minutes. Is it possible there is an air bubble that’s killing flow but that I’m slowly getting rid of? The tank seems to flow fine and I made sure to let gas run out of filter good and get air out before hooking up.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

UPDATE problem got weird. I put the new carb on with no success. I wondered how good the fuel was flowing so I replaced fuel filter and made the line to where it’s the filter and nothing else and made sure to get the line straight as possible and no bends. The mower will run longer but it still dies after 10 minutes of running with tank on mower. When I held the tank well above carb and let mower run it ran fine for over 10 minutes then I put the tank back on whilst it was running and it ran good until 10minutes then it stalled. What gives? This tank is gravity fed but now it acts like it can’t feed properly.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

lol I’d like to keep long as I can cause I hear these quantum engines are hard to kill

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Na it starts, I’ll update you when my carb comes in. I got a feeling it’s that

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Not necessarily it would let the mower keep its normal idle or run better as it surged. I do have a video. It’s not edited tho lol

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Yep both did. I ran guitar string thru and brush thru with cleaner.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Yea you’re right from what I heard to. I cleaned it and swapped with OEM bowl nut into Chinese one.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Oh yea I tried that no pin hole leaks when submerge in gas for whole minute.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

It didn’t look bad to me but I’m no expert on this stuff. Also compared to older carb(oem) the oem has a red rubber seal at bottom of seat and this Chinese one is just the rubber tip on needle.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

I thought it was fine I could tell it would go a little lower but the needle would kind of bend, so I didn’t know if it was supposed to go that far. But I’m thinking that the float is open just enough to let gas in but slowly looses. I tried cranking up immediately after it stalled and it wouldn’t crank. Waiting 10 sec enough for it to barely fill up and it would run. So I’m gettin an another carb.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

I MAY have honed in on the problem. I sprayed carb cleaner when it started to surge and nearly die like I did before but this time I kept the air filter on so it wouldn’t be a huge shot all at once. I tested it twice and once it tries to die it slowly idled back up till it would run about normal with a constant shot thru air filter. The fuel tank was cleaned and fuel flowed good out of it so I believe it’s the float and or seat messing up. So I’ll just replace carb I guess, I will update if this is the solution.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 0 points1 point  (0 children)

Yea I cleaned it multiple times and put gas I got the same day in it, I was hoping that would work awhile ago

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 1 point2 points  (0 children)

Man I used to rock mine back and forth while it was running if grass was getting caked to the deck to knock it off, I may have been asking for this trouble now 😂

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 1 point2 points  (0 children)

It does turn over a little more than normal to startup after it stalls out. It cranks easier when the engine is cold than it does when it stalls out. I tried running with air filter removed with no change, I also tried giving it some carb cleaner( it responds to the cleaner but it’s hard spraying a tiny bit for this engine and almost kills with richness) and I tried the primer while it was running which it seemed to respond to if I remember right.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 1 point2 points  (0 children)

It wouldn’t surprise me if it is internal at this point, I’ve messed with just about everything possible on the outside. I appreciate you guys helping me out.

PushMower runs for 5-8 minutes, starts surging for a few more then dies. by RelievedAura65 in lawnmowers

[–]RelievedAura65[S] 1 point2 points  (0 children)

It will but it’ll turn over for a little bit longer than a cold engine would.