Hey all, I have an older Briggs opposed twin on a MTD mower and I cannot seem to find out what the RPM is supposed to be for mowing. I've got some throttle work to do (new parts coming in) so I'd like to set it where it's supposed to be. When I got it, the mower was around 2600RPM full throttle but I raised it to 3000RPM. What's the safe limit for the blades and/or engine? Neither the engine manual or mower manual specifies. I also spent 15 minutes on the phone with MTD and right before hanging up on me they said "it varies from mower to mower".
Here's the model numbers:
Model: TMO-3400005A 135Q699H088
Serial: 1L214H30019
Engine: 422707-1214-01-9411185B
I set the engine speed on most tractors between 3000-3200 RPMs. Roughly 3200 for 38" decks, 3100 for 42" decks and 3000 for 48"+. Depends on the pulley sizes and if they are being used for mulching. Just the way I do it and I'm sure that you will get many other answers. It does vary by manufacturer and mechanic.
I could get the pulley sizes if it helps to narrow things down. I'm not so good with maths and figuring out what the blade tip speed is after passing through multiple pulleys. Anyway, I should have mentioned that this is a 46" deck with 3 blades on it. They're pretty small blades. I'm not sure what kind of blades they are (I haven't learned different types) but I don't bag, only side discharge. Thanks for the reply.
Alright. Before the work, my tach said I was running between 2880 and 2940 with the blades engaged and it cut amazingly well. I'll bump it up to 3100 and leave it.
