Tecumseh Enduro OHV XL/C 17.5 HP

Hi ,

I have a Tecumseh 17.5 OHV XL/C single cylinder engine that I posted about before . I took my old carb and two more off of motors exactly like mine and made one carb after trying all of them individually . I finally got it running , but the carb throttle butterfly and governer fluccate back and forth . I forget the correct term . It's like I'm revving the throttle up and down when I'm not . Any ideas as to what is causing this and how to stop it ? Thanks for any and all ideas .

The motor numbers are :
Model - OHV180
Spec. - 208001A
Engine Family - 3TPXS. 4902AA
DOM - 02304CB0248
Disp. - 490 CC

Thanks,
Whizkid

Have a Happy and Safe July 4 .

P.S. See my post under Tractor tales on this site .

The more than likely cause of your problem is dirt in main jet or idle passages in carb body(a common problem on tecumseh carbs)with dirty/plugged idle passages this will cause eng to surge/hunt for it's speed,as the govenor moves the throttle shaft/butterfly between hi & low speed jets to maintain eng set speed,if low speed/idle passages in carb dirty/plugged,when butterfly closes & eng tries to pull gas from idle jet & can't get same,eng slows down & govenor senses this & nudges/slams throttle to wide open position & eng gets gas off hi speed jet,then govenor slows eng down to match set speed & whole surging/hunting process starts over again OR the other possibility,govenor spring/linkages installed incorrectly or misadjusted.

Joe Csuti,


Thank you for the information however there was a couple of things that I forgot to mention that you reminded me of. One is that I cleaned the top metal part of the carb. ( the part that looks like a big heatsink ) as I said about the Briggs engine below this post I cleaned it with carb cleaner , poked it out with a small wire , blew it out with a air hose and soaked it over night in a gallon of Berrymans , ( I believe it was ) carb. cleaner . But , still that dosen't mean that it's clean and not stopped up somewhere . Another thing is the O ring / washer thing that the fuel solenoid presses up against in the bottom of the carb. bowl was closed up a little and I punctured the hole out a little bigger with a nail . I didn't soak the carb bowl as I thought that the carb cleaner might damage it , but there is some small holes that I couldn't get a wire into, muchless a lot of spray carb cleaner . I'll take it off tommorrow and try to soak the whole thing in carb cleaner. Is the stoppage in the hi / low jets in the carb bowl or the metal top ? I'm thing the bowl where the main jet is . Am I right ? How big should the hole in the fuel solenoid O ring be , the O ring that the fuel solenoid pressures the spring and stopper up against in the bottom / side of the bowl ?

Thanks ,
Whizkid

I looked at carb at partstree,there are low speed/idle passages in carb bowl & carb body,these passages could be dirty/plugged in either/both,if you look at carb drawing at partstree for your eng,you'll see a welch plug(47)in top of carb body,under same are passages that form a T,this is a favorite spot for dirt/gum to collect & block one/more passages,you'll probably have to destroy plug to remove,with plug removed you'll be able to run a wire/shoot carb cleaner thru air bleed vent,passage to carb bowl & low speed jet passage,after that you can buy a new welch plug & replace,the O ring may be soft/mushy due age & ethanol content of gas & need replacement,in addition you may have a leaking gasket where carb bowl meets carb body,idle passage passes thru this gasket from bowl & same may be leaking & idle passage sucking air,you're probably ahead of the game buying a rebuild kit for carb as you will have new parts & all parts needed to repair,then take it from there if you still have problem.

Is this the carb with the plastic bowl and NEITHER idle or high speed mixture adjustment?
If so I work on one of these about three years ago. The only way I could make it run was to drill out the Brass idle mixture jet and the PLASTIC high speed jet.

Kent