Idles Rough a lower speeds, and with blades engaged acts as if it’s bogging down. Any suggestions

[Paul Blaume]

 

[mgwin]

Welcome Paul!
I'm not familiar with newer cub cadets, but I would be guessing it is starving for fuel, or the fuel could have gone bad.
Other members will soon give more knowledgeable suggestions.

 

[Paul Blaume]

I replaced the gas, gas filter, gas pump, air filter, carburetor and the spark plugs

 

[gary noblit]

Paul,my question is..did anything change after adding all the new parts?

 

[Paul Blaume]

No no change

 

[jbratton]

Did you check the timing?

Edit: I see that you have a newer machine. Never mind.

 

[1811Cub]

I'd be looking for a partially sheared flywheel key. That would drastically affect timing.

 

[mgwin]

Years ago, the B&S motors on push mowers were notorious for that. I replaced a flywheel key once that you could barely see a mark on it, and you could not fell the mark. That fixed it though.

 

[gary noblit]

Paul,assuming that engine is a twin Kohler...my uneducated thoughts go to carb blockage inside the carb..point being not enough fuel to maintain rpm..depending on engine mod. if carb has adjustment screws or not..I've worked on a lot of modern cubs(not an xt1)...modern carbs the jets are so small it doesn't take much to throw the ratio out of balance...If I were working on it I would remove and clean carb completely...you have basically changed everything ....when you kick the deck in it's a load needing more fuel. that's my only clue.....

 

[Paul Blaume]

I removed carb cleaned and the even replaced with New carb.

 

[eweiss]

Make sure the fuel is getting to the engine. Pull the fuel line running from the pump to carb. Put the hose in a jar. Spin the engine over to observe the amount off fuel delivery. Should be a good pulsating stream.

 

[Paul Blaume]

yes and also I replaced the fuel pump

 

[gary noblit]

Paul, does it still idle rough as well?

 

[Paul Blaume]

Yes still

 

[jpaulus]

check compression and check valve clearances

 

[gary noblit]

Paul, you've got a lulu going on...Jerry said ,valve clearance,I agree.Have you seen any mouse wire damaged when the shroud was off?...There are so many possibles to a rough idle so there is really no magic answer...Is this engine single or dual coil.. a chance of 1 bad coil?? Can you turn deck easily by hand if so then it is engine related which brings me back to fuel... Is fuel pump vacuum type? Is line good and tight?...From this distance I'm sorry I can't be more help but I can only read what you write....Square 1 is start over and check every possibility again...sorry

 

[Ben Stoline]

Symptom sounds like fuel starvation.

1) Possible fuel tank lines restricted at the bottom of the tank, there may be a fitting that is clogged up depending on how its all plumbed in there. Had similar problem last summer with diesel John Deere units, every one had sediment strainer on the pick up tube full of dirt , years worth, blew it out with air.

2) Possible rubber fuel hoses getting old and restricted on the inside, replace all supply hoses.

Hope this helps.

 

[jpaulus]

It's difficult to believe it is starved for fuel at idle and still runs at full throttle. A very interesting problem. I can't wait to hear the solution. It sounds as if the fuel system has been totally replaced.

 

[tkhoffman]

Rough idle. Yet it runs up to high RPM. Gets cranky while under a load... I'm thinking, bad Spark. Make sure ignition wires are not jumping spark to the engine block. I had a problem with bad insulation right at the spark plug boots