CC Carryall 252 FE350 Excessive Lean Condition

[canterburya]

Calling all CC and Kawasaki experts! I am working with an FE350 engine in a Carryall. The engine will not run above idle unless you pinch off the intake hose and restrict the air flow. It is either getting too much air for the amount of fuel being drawn in or not enough fuel. I have tried known good carburetor parts from a good running engine. The compression is good at 155psi. I did a leak down test and the loss was only five percent. I thought maybe the cylinder head was cracked near the intake port so I swapped the head from another engine. No change. This one has me scratching my head. I have the engine out of the cart. I am running it on the bench. Any help in finding a solution to this problem is appreciated.

[CP241]

Couple things off hand.

Make sure you’re using an oem mikuni carb. I’ve never had good luck with aftermarket ones.

Also the intake system in the cart is quite restrictive. Running the cart on the bench without the complete airbox and the entire intake duct (most will run all the way under the cart and up under the cowl behind the dash). If it’s on the bench without the entire intake duct and airbox I’d expect it would run lean, it’s sucking in way more air than it ever would be able to in a cart

[canterburya]

Thanks for the reply. I think that I have figured it out. Someone had drilled holes in the bottom of the air box. This was throwing off the fuel/air mixture and causing the lean condition. Extra air was bring drawn into the air box outside of the plenum.

[CP241]

Originally Posted by canterburya

Thanks for the reply. I think that I have figured it out. Someone had drilled holes in the bottom of the air box. This was throwing off the fuel/air mixture and causing the lean condition. Extra air was bring drawn into the air box outside of the plenum.

That would do it too

These carts don’t like to have stock airbox, carb, or exhaust messed with.