Oil & Fuel 5252 starved for fuel?

[OhioGuy]

I'm having problems with my 5252, it appears to be fuel starved. It's a 25Hp Kohler Command. I'll be mowing and it will start sputtering and may even stall, I can usually keep it running by choking but not with enough power to mow.

I changed the fuel filter, what a poor location for that, inside the framerail under the tractor. I mowed for an hour and a half and it quit, same symptoms.

The next day, I pulled the fuel line at the carb stuck it in a bottle, (A Corona bottle works best for this test) turned on the key for 15 seconds and measured about three ounces. I then mowed for 20 minuted, it sputtered and stalled, measured again, (A fresh Corona bottle is recommended in the manual) about three ounces. Is it time to rebuild the carb, can I pressure check the fuel pump?

Thanks in advance for any ideas!

Curt

 

[DieselPower]

I'm not sure what's up with some of the new engines these day's but I have found a little trick that has fixed many of them. Everything from low HP push mowers to high 20's HP riding mowers. These new non adjustable carbs they stick on motors now day's seem to plug up at the slightest hint of dirt.

Try removing the air filter and completly plugging off the air intake with your hand. Crank the engine for a few seconds and then see how it runs. I know I have fixed a couple of friends push mowers and riders just by doing this, most all of them were fairly new models. The high vaccuum created by completly covering the intake seems to draw whatever spec of dirt is stuck in the carb out and they run fine after that.

 

[OhioGuy]

Thanks, I was leaning toward a carb problem, would have never thought of that trick.

Curt

 

[Cub5k]

I have a 5252 w/Kohler. I had a similar problem where the engine would start running rough etc. There is a rubber tube that I believe acts as a crankcase vent. It runs from the crankcase and into the carb inlet. I noticed something dripping from the tube. Not sure what it was but I suspected condensation. I rerouted the tube so that it did not drip into the carb and I never had the problem again.

 

[Mike5252]

I had a similar problem w/ a push lawn mower this summer. I kept working on the carb thinking it was a carb issue, but it turned out to be an ignition coil that was going bad.

 

[OhioGuy]

Hi guys,

I tried both suggestions, blocked the carb throat and cranked the engine and redirected the crankcase ventilation away from the carb and mowed for about an hour with no symptoms.

I'll mow another hour tomorrow but I'm hopeful one of these two tricks were successful.

Thanks for the help!!

Curt

 

[OhioGuy]

Well,
I mowed for about an hour an 15 minutes and the sputtering returned, I choked the running engine to a stall twice and verified the crankcase vent wasn't pushing anything into the throat of the carb.

I'm now leaning toward a heat related problem on the ignition side. The next mowing I'm going to hook up a spark indicator on each cylinder and see if I'm losing spark on one side. I believe this 25 HP Kohler uses an ignition module for each cylinder, my suspicion is that this is the third failed ignition module for me in the last three years. That's on three different Cubs, 1860, 1872, 5252.

It might still be a fuel problem, but it's so intermittent, it's hard to tell.

But on the bright side, I've got a trusty 20yr old 1872 as a backup. that sure takes the heat off these kind of problems.

Curt

 

[Cub5k]

Any chance of water in the fuel? Could your choke be creeping closed?

 

[OhioGuy]

I don't think it's a choke problem, when it starts to miss and wants to stall, I can keep it running by choking.

I've put about four hours on it running this way, the next mowing (tomorrow?) when it stalls I'll try pulling the fuel line at the carb, running some fuel out and reconnecting.

I also have the spark indicators hooked up, I hope thats not the problem, that's an engine pull.

Thanks for the ideas!

Curt

 

[FL4400]

My 1550 started doing the same thing and finally one day I started it and took off and it quit completely I thought it was a spark problem but ruled that out and then on to fuel. I found the the fuel line was completed blocked just outside of the tank. I was in a hurry that day to mow so I took a coat hanger and bent the end and reamed out the line. What came out was what appeared to be a break down of the rubber on the inside of the fuel line. It has been replaced the enitre way and I have not had a problem since.

 

[OhioGuy]

I'm sorta back to where I started, except I did rule out an electrical problem. The last mowing, the spark indicators were indicating good spark on both cylinders when it stalled out

When I replaced the fuel filter, I used a generic automotive filter because my Cub dealer didn't have one in stock. So I think I'll pull the deck again and start back at the tank. I think it's just not getting enough fuel at full RPM with the deck engaged.

Curt

 

[OhioGuy]

Well, I had some time today to try a few more solutions.
I removed the fuel filter and drained the tank into a can, I had plenty of flow and no obvious debris in the line.

I replaced the fuel filter with the right filter, it had to be ordered, the automotive filter was a clear case and had a bit of debris in it.

I split the carb and removed the top half and float, blew everthing out and re-assembled.

And just on the outside chance that this is a valve sticking when it heats up, I did a thorough cleaning with the air hose of all the engine parts.

Then I mowed for two hours with no symptoms. I'm still not sure it's fixed!

Then I discovered I have a huge grub problem, I was thinking the brown patches were due to lack of water but I noticed a lot of skunk diggings in the yard and when I examined one of the brown patches, it pulled up like a carpet, just like I've read about.

Dang, it's always something!

Curt