How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Curtis B. Your Own Question
Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 28889
Experience:  have worked on and around most engine models for 35 yrs./Polaris ATV expert
Type Your Small Engine Question Here...
Curtis B. is online now
A new question is answered every 9 seconds

I recently purchased a Mtd 15.5 HP Lawn tractor with a

Customer Question

JA: Hi. How can I help?
Customer: I recently purchased a Mtd 15.5 HP Lawn tractor with a Tecumseh OHV155 model#204509E motor Ive been having Issues getting it to run properly. I've cleaned the gas tank replaced the fuel lines and filter. Replaced the carburetor . Replaced the float bowl and fuel solenoid, Replaced the Stator and spark plug. Adjusted the Valve springs. Checked for sheared pin. At this point I have the mower running but really rough. and wont throttle up without backfiring. I can get it to run a little better if I remove the air filter housing.
JA: What's the make and model of the mower? And can you guesstimate how old it is?
Customer: I'm guessing the year is around 99
JA: Do you plan on doing the work yourself?
Customer: I'm trying to just hitting a point I cant figurte it out hoping you can help
JA: Anything else we should know to help you best?
Customer: I think I included everything I can think of.
Submitted: 2 months ago.
Category: Small Engine
Expert:  Curtis B. replied 2 months ago.

Welcome to JUST ANSWER small engines, let me try to help you !! I don't know it all, but maybe together we can get you a satisfactory answer!

Expert:  Curtis B. replied 2 months ago.

You set the valves a .004 inch? Do you have the old fuel solenoid from the carburetor? Take it and remove the working tip, and install it in the carburetor as a dummy, and run test.

Customer: replied 2 months ago.
I did set the valves to .004
from my understanding i put a screwdriver in the spark plug hole and turn the motor till the screw driver is furthest out then set the lash. I randomly read somewhere to turn the motor an additional 1/4 turn then set lash does that habe and validity?
I had originally snapped off the solenoid pin on the original because it was broken, then when I ordered a new carburetor it came with a new float and solenoid. I also replaced the gaskets on the carburetor and intake
Expert:  Curtis B. replied 2 months ago.

I would go back and check the valves again, turn till one valve is spring compressed, (open) and check the one that is up. Then if it is ok, turn till the ok one is spring compressed and check the other. You don't need to even remove spark pug!

Customer: replied 2 months ago.
Adjusted the valves again they where fine.
Still sounding like the timings off
also found of I try to come it she dies
But I can jam two fingers in the intake shroud that holds the air filter and then she'll throttle up but still rough with black smoke
Expert:  Curtis B. replied 2 months ago.

You are not getting enough fuel thrugh the carburetor. I would try the old fuel solenid , with the tip off, to see if it makes any differnce. Is this a gravity flow tank to he carburetor, or is there a fuel pump between? Is fuel pump working?

Customer: replied 2 months ago.
Its gravity
I'll try to switch the solenoid pout
Expert:  Curtis B. replied 2 months ago.


Customer: replied 2 months ago.
Switched out the solinoids no better
I feel like it's getting plenty of fuel.
Expert:  Curtis B. replied 2 months ago.

You are choking the engine, with hand, and making it run richer, the black smoke so it is not getting enough fuel through carb.

Customer: replied 2 months ago.
I guess the reason I question that is when I choke it normally it doesn't do the same it just dies. I can also see excess fuel being spit out of the carb and pooling up in the base of the air cleaner shroud.
Expert:  Curtis B. replied 2 months ago.

Did you remove the flywheel to check the timing key?

Customer: replied 2 months ago.
Keys in tact
Expert:  Curtis B. replied 2 months ago.

No damage?

Customer: replied 2 months ago.
I pulled the entire flywheel of last week and it looked great
Expert:  Curtis B. replied 2 months ago.

OK> I will opt out and see if someone else has seen this! Sorry.

Customer: replied 2 months ago.
Thanks for the help
Hope someone is familiar with this situation