notjustair
Well-known Member
I have an 18 horse flat head twin Briggs in my ZTR. It starts great and runs perfectly.
After mowing about an hour it will suddenly start to bog down. If I pull the choke up to half it runs like a top. It will do it a couple more times until I cap out at 3/4 choke. Mowing fine as long as you have it at the sweet spot. If it cools down a bit it will start all over again.
It has had a carb and fuel pump kit. The carb is adjusted well because it runs very well until it gets good and warmed up. I did take all of the shrouding off and clean it out - the engine isn't getting hot. I'm beginning to wonder if it is valves?
Thoughts?
After mowing about an hour it will suddenly start to bog down. If I pull the choke up to half it runs like a top. It will do it a couple more times until I cap out at 3/4 choke. Mowing fine as long as you have it at the sweet spot. If it cools down a bit it will start all over again.
It has had a carb and fuel pump kit. The carb is adjusted well because it runs very well until it gets good and warmed up. I did take all of the shrouding off and clean it out - the engine isn't getting hot. I'm beginning to wonder if it is valves?
Thoughts?
