lawnboy 10545 bogging down

[vwthingman]

Greetings all,
I have a old Lawn-boy 10545 self propelled mower that is bogging down after it has been running a while. It has a new plug and new air filter this summer. It seems like if the grass still has dew or is thicker, then it wants to die. I have to raise it up on the back two wheels and let it catch up. I do have a Gator blade on it, but I have ran it for several years on this mower so I doubt that would be the issue. Any help is truly appreciated.

Thanks

 

[Rand]

those can have ignition/coil problems.
other than that maybe a carb problem?

 

[Lawnman23]

Did this problem start occurring all of a sudden or did it gradually get to this point?

Just to get an idea of what's what:
1. Has the carb ever been apart for cleaning/service?
2. What type of gas and oil do you mix for it?

 

[vwmaniaman]

When I got my lawn oy out this spring it would not start. I pulled out the spark plug and checked it and pulled the rope and it sparked OK, so it was on to the carb and exhaust port. Port checked and its open. Carb has a bubbled up looking float and the main jet was plugged solid. I am not sure if something in the gas melted the float and then plugged the jet or what. I had to work at it to get it open with my torch tip cleaners from Harbor Freight, but the ethanol gas leave a film in the jets that narrows then so they are actually smaller in the bore. The cleaner looks like it has varnish on it when I pull it out and no carb cleaner short of dipping it will clean it. That may be your issue.

 

[fdcg27]

The only problem I ever had with my LB was that I needed to clean out the exhaust ports, probably due to using cheap 2-stroke oil at a higher than needed ratio.
Maybe a shot of either each spring, but after that the thing always ran like a beast.
These are nice mowers, good luck in keeping yours functional.

 

[CleanSump]

Have you considered using Yamaha Ring Free to clean and keep your 2-stroke motors running well?

 

[grasscutter]

9 times out of 10 it's the carburetor. Because your average person has no idea how a carburetor works and how susceptible they are to fuel contamination. Before I remove the fuel filler cap, I make sure that all the grass is off my forearms and that there's no grass or dirt around the fuel filler cap. I also check the gas can for contamination on the outside of it too. I keep a paint brush nearby for dusting off equipment next to the fuel fillers.

 

[bunnspecial]

If you've not done so recently, pop the muffler off and clean the exhaust ports. The 10545 is an F engine, so should have an under-deck muffler.

I mow with nothing but two stroke Lawn Boys, and my most used one is from 1974 with a D600 engine(one generation behind the F engine). It can chew through decently thick grass, and when I've used E and F engines(I have a few of both out in the garage/collection) they seem unstoppable. When I start to notice a loss of power, I always go to the exhaust ports.

A little carburetor love can be good too, but there's not a ton you can do beyond cleaning the jets.

I'll mention too that all of my LBs get fed Lawn Boy Gen II oil mixed at 32:1(8 oz bottle in 2 gallon can). This is a TC-W3 oil, which a lot of folks will say isn't "appropriate" for lawn equipment. Remember that these engines-especially the F engine and prior-were designed by a company known for 2 stroke outboards. I have seen technical bulletins where they addressed this very topic, and basically said that TC-W3 was appropriate for the relatively slow, cool running lawmower engine. I mention this as I've noticed the proper LB Gen II oil leaves fairly soft soot deposits that mostly wipe off and, at worst, take a minimal amount of work with a wooden dowel to loosen up.

 

[FZ1]

Greetings all,
I have a old Lawn-boy 10545 self propelled mower that is bogging down after it has been running a while. It has a new plug and new air filter this summer. It seems like if the grass still has dew or is thicker, then it wants to die. I have to raise it up on the back two wheels and let it catch up. I do have a Gator blade on it, but I have ran it for several years on this mower so I doubt that would be the issue. Any help is truly appreciated.

Thanks

Get the blade sharpened.

 

[Lawnman23]

If you've not done so recently, pop the muffler off and clean the exhaust ports. The 10545 is an F engine, so should have an under-deck muffler.

I mow with nothing but two stroke Lawn Boys, and my most used one is from 1974 with a D600 engine(one generation behind the F engine). It can chew through decently thick grass, and when I've used E and F engines(I have a few of both out in the garage/collection) they seem unstoppable. When I start to notice a loss of power, I always go to the exhaust ports.

A little carburetor love can be good too, but there's not a ton you can do beyond cleaning the jets.

I'll mention too that all of my LBs get fed Lawn Boy Gen II oil mixed at 32:1(8 oz bottle in 2 gallon can). This is a TC-W3 oil, which a lot of folks will say isn't "appropriate" for lawn equipment. Remember that these engines-especially the F engine and prior-were designed by a company known for 2 stroke outboards. I have seen technical bulletins where they addressed this very topic, and basically said that TC-W3 was appropriate for the relatively slow, cool running lawmower engine. I mention this as I've noticed the proper LB Gen II oil leaves fairly soft soot deposits that mostly wipe off and, at worst, take a minimal amount of work with a wooden dowel to loosen up.

Cleaning out the ports is a good thing to check but plugged ports wouldn't explain why OP's runs good for a while and then starts bogging under load.

That says lack of fuel, not restriction of exhaust.