Choke Controlling RPMs...Idling Problems

[Xtreme Cartz]

I put a new 13hp HF engine in the limo this week after the old one finally went bad. I'm having trouble getting this to idle properly. Starting it, the engine revs up very high with the choke half way. Then pushing the choke in causes the rpms to drop and it dies at idle. All linkages are the same as were on the old engine and it never happened before. Any ideas what I should check? Thanks!

[Xtreme Cartz]

Well, I returned the engine's throttle controls back to stock with the gov spring, wanting to get an idea of how it runs out of the box. Something must be adjusted or setup wrong from the factory. Choke halfway causes the rpms to jump high and the clutch engages. Now with the controls back to stock, push the choke in and the engine surges at idle. There is no throttle control. The throttle linkage connecting to the carb bounces around back and forth and when held still, the engine dies.

[TheNewGuy]

Wow that sucks, can you exchange the engine?

[sho305]

If you change the airbox or muffler you have to rejet. They break off the idle jet you can get one on ebay, cut a slot in it, heat it up and it will come out. Or you could try your old carb on it. I don't understand what you are saying about the linkage, but I didn't use the governor either on a 16hp.

[Xtreme Cartz]

Ron, that is what I may end up doing. They are pretty good about exchanges. Just have to pull the engine out of the cart again and hope they take it back. The original engine was 1.5 yrs old when the starter went bad. HF said they dont carry replacement parts in the store, so with the 2 year warranty they just replace the entire engine. Cool. Well I pulled it from the cart last week, got the new one painted and prepped to go back in. Filled with oil and then noticed a huge puddle under it. The bottom of the block was cracked. So, I took that one back to HF and got this newest replacement. Did all the prep work with fuel pump, painted again and installed the engine. Come to find out it doesnt run right. I've had pretty good luck with the hf engine in my cart until now. I'm thinking it's a great time for a Vtwin upgrade!

[Xtreme Cartz]

Originally Posted by sho305

If you change the airbox or muffler you have to rejet. They break off the idle jet you can get one on ebay, cut a slot in it, heat it up and it will come out. Or you could try your old carb on it. I don't understand what you are saying about the linkage, but I didn't use the governor either on a 16hp.

I made an exhaust for it without using the stock muffler and snorkled the intake, but all of that was on the old engine which ran great. Everything is setup the same as before, but this new engine runs badly(surges at idle). I would swap the carbs but they took the old engine for the warranty.

[csason]

Originally Posted by Xtreme Cartz

I made an exhaust for it without using the stock muffler and snorkled the intake, but all of that was on the old engine which ran great. Everything is setup the same as before, but this new engine runs badly(surges at idle). I would swap the carbs but they took the old engine for the warranty.

if it was me, I would disconnect ALL the linkage, down to where I could manage the throttle with my fingers, and then test it.

If is still does it that way then pull it, I guess..

If it does it with no linkage attached and just start the engine, with your thumb on the the throttle at a reasonable idle setting, and it surges.. I guess something is wrong, don't know what would cause that..

[sho305]

I put a car muffler and car airbox in my carrolstream clone (Lifan 16) and had to hog the jet WAY out to get it to run right. It would start and run but surged, and when you hit the gas it pretty much didn't run at anything over half throttle. It should idle though, if its lean you just keep the choke on some and it should run. If not it may be an engine issue. On mine the choke has nothing to do with the throttle, unless the governor on yours is trying to speed it up...I took that off this one.

[DOOmsman]

Is it the internal governor causing the throttle to surge?