149 possible engine knock
 

Have a pretty rough 149 that I bought last winter. Rebuilt the carb, set the time using static method, had the s/g rebuilt and now it starts and runs decent. As you rev the engine I can hear a knocking noise that I believe is coming from the engine. Do not hear the noise at idle, but my hearing is not the best. When the engine is put under load as in going up hill with mower running, I can no longer hear the noise. I know it is difficult to diagnose a noise not being able to hear it but thought some one may have encountered the same symptoms. Any help will be appreciated. Sorry for the long post. I check the forum every day and usually learn something new. A lot of smart cc people here.
Bob

Most of the time it's the front PTO clutch disc knocking, can't say for sure, but it's the first thing I would check.

Of course it could be a lot of different things making the knocking noise, but for my 149 it was the balance gears were in several pieces in the oil pan. I removed mine and did not replace them, as per advice from many people. The engine shakes just a little bit more now, but nothing that I am going to complain about. I hope that is all that is up with your 149. Keep us posted.

Cub Cadet 123

I agree with Ben. If it doesn't make the noise with the PTO on, it's probably the PTO clutch.

I had a 1450 that made a knocking sound similar to what you describe I found by removing the head that the piston had wore and was rattling inside the bore. I hope it's something simple like the pto on your 149, I also have a 149 a fine machine

It could be any number of things, rule of thumb would be that a rod in an engine will knock louder when under a load.

If you don't find the problem on the outside of the engine, I do believe that I would be checking (and removing) the balance gears if they are still in there before they escape on their own.

Good luck.

Agree with these fellers, check the external stuff out first and then move to the internals. A big second on looking into the balance gears. The ones in my 14hp were just kind of sagging on their spindle....it's a wonder they hadn't already grenaded the motor.

on my 72, the pto clutch disk "teeth" (the pieces that stick out into the basket pulley to drive it) are rather worn down and the anti-rattle springs are all long since departed. that creates my knocking sound. to test, with the engine not running, engage the PTO and try turning the PTO pulley by hand. if you get a good amount of "wiggle room," that could be your knocking sound.

Drain some oil, and look carefully to see if you have any aluminum powder/flakes in it. Put a couple drops on a paper towel and let it sit for a while. If you see metal powder, it's likely the piston is worn and you're looking at a rebuild.

149 possible knocking
 

Thanks for all the input. Let me add to my original post. The knock is still there when pto is engaged but not as loud when the engine requires more power like going uphill. Did the old timers screw driver test on it today. I could hear the knock with the tip of screw driver on non engaged pto and screw driver handle to my ear. Put the screw driver several places on the engine and the loudest sound was with the screw driver on the exhaust fins as it comes out of the block. Could a blown head gasket cause this or a valve adjusted too loose? Tomorrow I will try to check some of the things that were suggested. Thanks again for all the help and support.

Bob

Carbon build-up in the head can cause a bit of knock, which is where you just described the loudest source.

Not a bad time to order a new head gasket (make sure to get an OEM Kohler gasket with the fire ring). Remove the head, scrape all the carbon off from the head and cylinder top, and then go ahead and resurface the head. It's an easy job, requiring only a nice piece of flat glass and some dry/wet sandpaper.

This might just cure the knock, and most likely is time to be done anyway.

I know the cost of a roll of gasket material from Tractor Supply is $9.97. Pull the 321 and remove the oil pan and preform a inspection. Look inside the engine for worn metal walls, or components. Hope you get the knock problem figured out one way or the other!

There so so many things that can cause sounds like this. About the only way you can find the problem is a step by step trouble shooting procedure. Check all the items on the outside of engine possible, next you can remove head checking carbon build up along with the piston, then pull engine and check bottom end, if I were to go to the trouble of pulling engine/pan I would plan for a rebuild. The suggestions from people here will help you identify the problem... it's now a matter of finding out the problem

Bob can you post a video of the knocking noise? Maybe at varying speeds and loads, that may help identify it better

149 possible engine knock
 

Yesterday I checked the pto per cadzag72's instructions. It had about 1/4 " movement and it would make a clunking sound by turning it quickly clockwise or counter clockwise. Looks like I need a pto rebuild. Today I am going to a local Cub Cadet store and try to pick up a Kohler head gasket. Will then pull the head and de-carbonize it. Once The pto and top end is fixed, I am hoping the knocking noise will be gone. Don't know if I can post a video with sound. I will give it a try maybe later today. Thanks again for all the input.

Bob

Sounds like a good plan Bob. Whenever I de-carbonize, I use the Super Kleen (purple container) found in Wal-Mart. Be sure to use proper protective eye wear and GLOVES as it removes all grease and grime--including the oil from your skin. I never have to scrape when I use that stuff, so it saves me a lot of "elbow grease" (Always give the laziest man the hardest job and he will find the fastest way of getting it done!). Let us know how your situation works out.

Cub Cadet 123

Sounds like that might be it. Hopefully, it will do the trick!:beer2:

I agree! :beerchug:

149 possible engine knock
 

Went to the local cub dealer to get Head gasket. Did not have one in stock, had to order. Ordered one made by Kohler , hope that is what I receive. Went to the Out Building and started the cub.Amazingly I was able to make a video using my Ipod. I am not good at this sort of thing so don't expect too much. First started with out pto engaged, then changed speed of engine. Then engaged the pto and varied speed of engine. I doubt that one will be able to determine anything with all the noise. I do know that it has a exhaust leak where the pipe exits the engine. Thanks again for all the support.

Bob

Could not get the video to upload. Showed connecting to occ but waited 30 minutes and nothing happened. Need some advise.

Advice: Throw the IPOD in the trash and invite everyone on OCC to your place to hear your cub and have a plow day in your backyard and your neighbor's backyard. Be sure to fix lots of cookies (chocolate chip and snickerdoodle) for the members, then have a very large barbeque and hogroast in your backyard to feed all those present. We can listen to your cub and have a great party!!! :beerchug: After 30 minutes, I'm sure something will happen--be sure to withdrawal enough money from the bank to post our bail. :ROTF2::Slap: I already spent most of last week in jail anyway, but I was able to roll doubles a few times and get out before all of the real estate was sold!:biggrin2:

Just funnin'. I don't know much about uploading a video, but before you accept that head gasket, look closely at the internal perimeter of the gasket--the part that goes around the upper chamber. The good ones will have that sealed up or wrapped and the ones that you don't want will not have it sealed up, so you can actually see the layers of the gasket if you look very closely at it. If it is a genuine Kohler head gasket, then it's a quality part.

Cub Cadet 123

The simplest way with an apple device is to use a hosting site with an email upload feature ( I use photo bucket) email your video to the address in the Menu under upload. Then copy and paste the link to OCC.:beerchug:

One easy way to de-carbon an engine is to run it about half throttle after it gets to operating temperature and mist a water spray into the carb, just enough to make the engine stumble. Do this for about 30 seconds.

very interested to see what becomes of your head gasket replacement...i hope it fixes it. i noticed with my k301 it seemed to be making a slight knock noise and when i would increase the throttle somewhat quickly it looked like a small amount of smoke would escape from between the jug and head....already knew a rebuild was in my future...good luck to you..

149 possible engine knock
 

Cub Cadet shop called and said my head gasket was in. Turned colder here and snowed a little last night. Will probably pick up head gasket tomorrow and maybe get started on it by the weekend. Worked hard yesterday and need to rest today. Also working on my brothers simplicity riding mower. Picked up a new solenoid for it. Need to get it running again. Also need to build a head resurfacing tool out of glass and wood. Will be busy once I get started again. Every one have a great day.

Bob

It snowed and your brother needs his mower fixed? Where are your priorities???:biggrin2:

hope pto and the top end are the extent of your troubles! those pto springs are a bit of a pain (the little ones, not the big triangular one), but they do stop that noise from the pto pretty well. good luck!

149 possible engine knock
 

Thought I would give an update for any one interested. Got my Brother's Simplicity up and running. It was the solenoid that was bad. And to Sawdustdad, I always put Family before any thing. Cub 123, your suggestion for a hosting site was a good one, but I am too old to try something like that. I hope to get the head pulled off the 149 this afternoon after it warms up a little. Will post some pictures and hopefully get some opinions as to what needs to be done. Thanks for all the support and have a great day.

Bob

Thanks for the update!