kawimaniac2145 6 #1 Posted July 11, 2021 i have talked on here before and am having a problem with my onan p220g surging. i cant seem to figure it out. i rebuilt the carb once already, and cleaned it more than 5 times and is clean but is still surging here is a link to my youtube video. Share this post Link to post Share on other sites
kawimaniac2145 6 #2 Posted July 11, 2021 thanks in advance Share this post Link to post Share on other sites
lynnmor 6,706 #3 Posted July 11, 2021 Is the 3/8” Welch plug in place that is just above the idle mixture screw? Did you remove it to clean behind it? Did you adjust the idle mixture? Did you adjust the float as shown in the manual? Is the float in good condition? Are the linkages in the proper holes? Share this post Link to post Share on other sites
WheelHorse520H 706 #4 Posted July 12, 2021 I have a similar problem, you could try to spray brake cleaner around the gaskets on the intake and if it changes pitch then you have air entering at a seam. Here is the link to the thread I started for the same problem. Link. Andrew Share this post Link to post Share on other sites
Jeff-C175 7,195 #5 Posted July 12, 2021 44 minutes ago, WheelHorse520H said: spray brake cleaner around Brake cleaner not for me. That stuff is nasty. Takes paint off. Use starting fluid instead. 1 Share this post Link to post Share on other sites
lynnmor 6,706 #6 Posted July 12, 2021 Some brake cleaners are non-flammable and they will not prove anything if used. 1 Share this post Link to post Share on other sites
stevasaurus 22,197 #7 Posted July 12, 2021 carb cleaner is the best to use. 2 Share this post Link to post Share on other sites
kawimaniac2145 6 #8 Posted July 13, 2021 If y’all are talking about spraying stuff on the intake to see if you have blow by I don’t. I just don’t know what to do next should I put that welsh plug-in would that help Share this post Link to post Share on other sites
Jeff-C175 7,195 #9 Posted July 13, 2021 28 minutes ago, kawimaniac2145 said: to see if you have blow by I don’t Not 'blow by', but rather a vacuum leak. That's a different thing than blow by. Those Onan intake manifolds are known to leak between the two halves of the manifold. Are the shafts on the throttle plate, and the holes in the carb where the shaft runs in tight? Could be sucking air there also. Might need to install bushings in them. 2 Share this post Link to post Share on other sites
lynnmor 6,706 #10 Posted July 13, 2021 1 hour ago, kawimaniac2145 said: If y’all are talking about spraying stuff on the intake to see if you have blow by I don’t. I just don’t know what to do next should I put that welsh plug-in would that help You spray to see if the stuff is sucked in and the engine changes speed. Don't tell me, after all of this, that you are actually trying to run it with the welch plug out. Share this post Link to post Share on other sites
kawimaniac2145 6 #11 Posted July 15, 2021 Will putting in the welsh plug in help the running 1 Share this post Link to post Share on other sites
Tuneup 1,412 #12 Posted July 15, 2021 Hey there, Mr. Kawi (I had a KZ650 once)... That plug covers a small reservoir that is key to the idle circuit. My 16's was missing when I got the tractor and did exactly as yours. That circuit also impacts the tractor in mid-range with these carbs. Get that carb off and replace replace the plug. Take that opportunity to go through the carb and adjust it properly. The float set especially. Share this post Link to post Share on other sites
lynnmor 6,706 #13 Posted July 15, 2021 11 hours ago, kawimaniac2145 said: Will putting in the welsh plug in help the running On June 11 I mentioned the welch plug. Share this post Link to post Share on other sites
kawimaniac2145 6 #14 Posted July 19, 2021 update: i am trying to source out a 3/8" welsh plug. and nappa didn't have it, my local hardware store didn't have it. and jackssmallengines.com had them. i types in welsh plug. and they had them. but didn't label it as 3'8 under specs. so i am going to try my local small engine repair shop. and another online places. i will keep you updated. Share this post Link to post Share on other sites
kawimaniac2145 6 #15 Posted July 19, 2021 if yall can find one. and send me a link i would appreciate it. Share this post Link to post Share on other sites
Jeff-C175 7,195 #16 Posted July 19, 2021 (edited) 1 hour ago, kawimaniac2145 said: i types in welsh plug Try spelling it with a C instead of an S; i.e. WELCH plug I think you want ALUMINUM for use in your carburetor, yes? (although it appears that Mrs. Google will fix that for you anyway, so never mind) By the way, if you can get your finger to cover the hole safely while the engine is running, it would give you a good idea if that missing plug is the culprit. Here's one for 88 cents, otherwise there are several places that will sell a 10 pack for about a buck each. I'm sure if you order one they're going to hit you for $10 shipping anyway! http://www.tsracing.com/Welch-Plug-38-HL304-HL348-Tillotson-P3609.aspx Here's their shipping rates from Bushnell, FL @Zeek to NJ. Definitely go for that "KART Shipping" ! holy crap, are they kidding? Edited July 19, 2021 by Jeff-C175 Share this post Link to post Share on other sites
John2189 404 #17 Posted July 19, 2021 Does it have that small anti surge spring on the carb linkage? Sometimes the hook wears off 1 Share this post Link to post Share on other sites
kawimaniac2145 6 #18 Posted July 19, 2021 36 minutes ago, John2189 said: Does it have that small anti surge spring on the carb linkage? Sometimes the hook wears off yes the spring is still intact. Share this post Link to post Share on other sites
kawimaniac2145 6 #19 Posted July 19, 2021 57 minutes ago, Jeff-C175 said: Try spelling it with a C instead of an S; i.e. WELCH plug I think you want ALUMINUM for use in your carburetor, yes? (although it appears that Mrs. Google will fix that for you anyway, so never mind) By the way, if you can get your finger to cover the hole safely while the engine is running, it would give you a good idea if that missing plug is the culprit. Here's one for 88 cents, otherwise there are several places that will sell a 10 pack for about a buck each. I'm sure if you order one they're going to hit you for $10 shipping anyway! http://www.tsracing.com/Welch-Plug-38-HL304-HL348-Tillotson-P3609.aspx Here's their shipping rates from Bushnell, FL to NJ. Definitely go for that "KART Shipping" ! holy crap, are they kidding? thanks for the link bud. that helps out alot. Share this post Link to post Share on other sites
kawimaniac2145 6 #20 Posted July 20, 2021 4 hours ago, Jeff-C175 said: Try spelling it with a C instead of an S; i.e. WELCH plug I think you want ALUMINUM for use in your carburetor, yes? (although it appears that Mrs. Google will fix that for you anyway, so never mind) By the way, if you can get your finger to cover the hole safely while the engine is running, it would give you a good idea if that missing plug is the culprit. Here's one for 88 cents, otherwise there are several places that will sell a 10 pack for about a buck each. I'm sure if you order one they're going to hit you for $10 shipping anyway! http://www.tsracing.com/Welch-Plug-38-HL304-HL348-Tillotson-P3609.aspx Here's their shipping rates from Bushnell, FL to NJ. Definitely go for that "KART Shipping" ! holy crap, are they kidding? hey bud. thanks again i just ordered 2 thanks again for the link 4 hours ago, Jeff-C175 said: 1 Share this post Link to post Share on other sites
Zeek 2,283 #21 Posted July 21, 2021 (edited) On 7/11/2021 at 3:33 PM, kawimaniac2145 said: i have talked on here before and am having a problem with my onan p220g surging. i cant seem to figure it out. i rebuilt the carb once already, and cleaned it more than 5 times and is clean but is still surging here is a link to my youtube video. I went through this with a Kohler Courage 26 HP. After doing exactly what you did wasting hours of my time, I finally threw the carb in the garbage and got a new one from Amazon. Here's yours for $37. I put the new one on with zero adjustment and it ran like new. Edited July 21, 2021 by Zeek 1 Share this post Link to post Share on other sites
kawimaniac2145 6 #22 Posted July 25, 2021 that welsh plug did not help now its running rough Share this post Link to post Share on other sites
Tuneup 1,412 #23 Posted July 25, 2021 But it's running differently so that plug did something. Surge gone? The idle adjustment is very sensitive. You can get her really smooth at 1200 with a fresh filter. Mine took several adjustments until I got it right. Share this post Link to post Share on other sites
WheelHorse520H 706 #24 Posted July 25, 2021 6 minutes ago, Tuneup said: But it's running differently so that plug did something. Surge gone? The idle adjustment is very sensitive. You can get her really smooth at 1200 with a fresh filter. Mine took several adjustments until I got it right. I agree if it’s running rough then that plug did do something. And yes the idle is sensitive, did you adjust it to make the surging go away at all? That could cause it to run differently, not that I think about it though I am not sure it was cause it to run rough. Anyway if the surging is gone then you made progress, it’s like my dad always says “two steps forward and one step back”. Andrew Share this post Link to post Share on other sites
kawimaniac2145 6 #25 Posted July 26, 2021 it still surges at high rpm and how do i adjust it. Share this post Link to post Share on other sites