Low power 18hp in an 1872????
 

I have noticed here recently that the 18hp in my 1872 doesnt seem to have the power it used to. It has a 44" deck on it (not original I know), I have checked it & it is clean, no buildup on it. But when mowing it seems to really bog down, doesn't seem like the governor is adding fuel to raise rpm/power. Is there anything I should look for to try to figure out why the loss of power? You think a tune up will help much, or maybe engine is wore out. I haven't checked compression yet, and I can tune a carb about as well as I can tuna fish..... (sorry).

Thoughts?

Thanks

If it's running fine aside from power, I'd check compression first and foremost.

What range of compression is considered "OK", and below what level is bad?
Thanks

Book will tell you that 90 PSI is the minimum, but both cylinders need to be within (I think) 10% of each other. So one at 90 and one at 95 is ok, but one at 90 and one at 110 is not.

How recent? Have you noticed and smoke? Any loss of oil? Is it just the deck that seems weak?

Take a look under the deck and see if you have a bunch of grass buildup. Check and make sure the spindles and mule drive pulleys are not binding.

What Sam said plus look closely at the idler arm on the mower deck to see if it is holding proper tension on the deck belt. If the deck checks out ok...then maybe the engine is just getting tired.

I don't want to sound silly, but have you replaced the air cleaner recently? :bigthink:

That's actually not silly at all.. good point!

The Idler Beth mentioned in post #7 will mimic the condition you describe.
Deck seems to slow down and engine don't compensate for a phantom load.
Most of those are neglected and are dryer than a popcorn fart.:biggrin2: