KohlerM14 tappet noise

[Dennis C. 142]

Recently purchased a rather nice Toro WH 314H with 540 hrs. Machine is well kept and clean, all controls work.

 After starting the engine I noticed tapping noise which increased with more throttle. Could this be tappet adjustment

or something more serious? As discovered a crankshaft seal leak but that  can be fixed. Thanks. Red Square is my

go to place for help!!!

 

[Herder 2,354]

A valve adjustments is a good place to start.  Over the years I've adjusted many, is most cases it has removed the tapping.  I always check the clearance prior to making an adjustment, this will let you know if it needs it.  I have had some that needed to be and some that haven't needed to be adjusted.  Have you done an oil change?  Proper viscosity could play a part in how noisy it is.  Some preferer using synthetic oil, it is thinner and you may hear more engine noise. 

 

Maybe it's just been my luck, but most of the Magnums I've owned, tapped.  I have one currently, a 10HP and when I got it it both valves tapped, after serval attempts the intake valve is still tapping.  O well, I just run it.                

[kpinnc 12,088]

Agree with what is already posted- valve adjustment is the place to start. 

 

If it becomes excessive (think hammers in a dryer), it could be more involved. Worn piston rod or crankpin, bent valve, or other issues would be the worst extreme. Luckily Kohlers are rebuildable, and there's another 20-40 years of life in it!

 

A little tick isn't completely uncommon. 

Edited August 19, 2021 by kpinnc

[Dennis C. 142]

Thanks

[kpinnc 12,088]

I would add- if the valves check out, might be worth taking the head off and doing an OSI (obvious um stuff inspection). Could be heavy carbon or even something small ingested banging the top of the piston.

[Dennis C. 142]

Thanks Kinppc. I'm hoping it's valve adjustment as the tractor is all original and been garage kept. Heck it only has 540 hrs.   Checked the oil and

it is clean. The ticking isn't loud, just noticeable. Engine does seem hot though, that normal?

[Snoopy11 5,714]

Getchya a good old mechanic's engine stethoscope... stick on valve cover and various bolts of valve cover.

 

Just want to make sure this is valvetrain noise, as sometimes rod-wristpin issues can resemble valvetrain noise, particularly on Hemi engines...

 

Don

[kpinnc 12,088]

3 hours ago, Dennis C. said:

Thanks Kinppc. I'm hoping it's valve adjustment as the tractor is all original and been garage kept. Heck it only has 540 hrs.   Checked the oil and

it is clean. The ticking isn't loud, just noticeable. Engine does seem hot though, that normal?

 

Just for grins- probably a good idea to check under the tin for mouse nests or grass clippings. Not much else I can think of "normal" things that would make a Magnum run hot. Fuel mix lean maybe but not likely. Good clean air filter on it?

 

Maybe it's just that external mounted muffler that seems hot?

[oldlineman 1,481]

Maybe muffler restriction? Bob

[Dennis C. 142]

Engine only has 540hrs on it, I doubt a bad muffler. I will remove the tin when I check the tappets and check for mouse nest.

Not really a good engine diagnostic guy. Thanks for the input.

 

[oldlineman 1,481]

The baffles have been known to rust inside and come loose i had one do that didn't heat up just made noise. Bob  

[Dennis C. 142]

Thanks

[Dennis C. 142]

Today I decreased the entire engine and inside the hood. Lots of oil film, even the deck belt was saturated.

I also decreased the entire deck and reassembled.  Upon further inspection of the engine the breather tube was

disconnected and most likely off for many years. The plug had never been changed in 540n hours. The entire

engine and all the guards are clean. Next I dissembled the breather to get at the tappets. The clearance was huge,

guessing I would say .030 on both valves. I expect this is why the engine ran hot, as the exhaust valve may not have

been opening fully to release all the hot gases. just a thought. Set the tappets according to the manual. Installed a new

breather filter and gaskets. Installed the carb and filter and made sure the breather tube was attached firmly. Since I'm

waiting on a plug I turned the engine over without the plug, no  weird noises. So I think the tappets are set OK. Next to

pull the drive pulley off and see if the output seal is leaking. I bought a new one just in case. Hope it is OK. Next

to get the deck back on and see how the engine runs. Thanks for all the advise!!!

Edited August 27, 2021 by Dennis C.
miss spelling