k181 only turns 1/2 round

[chasdrng 5]

Hello everyone

I'm new here and need some help I just had my K181 worked on and during the first time I started it I saw I had a problem. So here's the work he did. He replaced carb, piston, rod, rings, and cleaned off the top of the valves. I got it installed and started it and everything went good for a couple minutes then you could see smoke coming from the little hole in valve cover (maybe a vent) and you started hearing a slight squeal that would come and go. When I killed it the engine seemed very hot so I let it cool down and now when I try to start it the engine only turns about 1/2 turn then stops. When it stops it is either on the magnet on the flywheel or just opposite of it. If you hit the key again it does the same thing again. If you pull the plug it spins fine and seems to have very good compression. I charged the battery all night and this morning it's still doing the same thing also checked the battery at work with a battery tester and it says good with 440CCA. Never had this issues till now. Hopefully someone will have some ideas to share. The guy took it back apart and he said the small spring on the ACR is in place and he was going to see if he can adjust it some to try to tighten it up some. He is also pulling the flywheel to check the magnets on the stator while he's inside it. Open for ideas on what could be happening
Thanks for your advise.

[Tractorhead 9,212]

Hi an  to 

 

i‘m to too experienced in Kohler Engines, but about your description, it sounds to me like a

wrong oil delivery to piston, so i would double check if the connecting rod was inserted in the right direction.

This beeing splash lubed Engines, wrong rod direction will happens in too less oil splash.

As a result was insufficient oil supply.

 

hope it was anything different.

[Achto 29,546]

 

If it spins free with the spark plug out, it may be that the timing is off. If it is trying to fire too soon before the piston reaches top dead center it would stop the rotation.

 

First check to see if your battery cables are installed correctly. If they are reversed it could cause this issue. Not questioning your ability but mistakes happen.

Check the fly wheel position and key.

[The Tuul Crib 7,339]

It also sounds like the acr spring as well . 
Some of the early motors didnt have them

T😎

Edited September 18, 2020 by The Tuul Crib

[Ed Kennell 42,481]

 to the 

 

Several of your  symptoms could indicate a blocked exhaust.      What was the engines problems that caused you to do the rebuild?   

smoke from breather

hot engine

 

 

[WHX?? 52,276]

[bc.gold 3,406]

12 hours ago, chasdrng said:

Hello everyone

I'm new here and need some help I just had my K181 worked on and during the first time I started it I saw I had a problem. So here's the work he did. He replaced carb, piston, rod, rings, and cleaned off the top of the valves. I got it installed and started it and everything went good for a couple minutes then you could see smoke coming from the little hole in valve cover (maybe a vent) and you started hearing a slight squeal that would come and go. When I killed it the engine seemed very hot so I let it cool down and now when I try to start it the engine only turns about 1/2 turn then stops. When it stops it is either on the magnet on the flywheel or just opposite of it. If you hit the key again it does the same thing again. If you pull the plug it spins fine and seems to have very good compression. I charged the battery all night and this morning it's still doing the same thing also checked the battery at work with a battery tester and it says good with 440CCA. Never had this issues till now. Hopefully someone will have some ideas to share. The guy took it back apart and he said the small spring on the ACR is in place and he was going to see if he can adjust it some to try to tighten it up some. He is also pulling the flywheel to check the magnets on the stator while he's inside it. Open for ideas on what could be happening
Thanks for your advise.

 

A mistake made all too often, mechanics accustomed to working liquid cooled engines gap the new rings as it they were going into a liquid cooled engine while the air cooled engines require a much larger end gap to compensate for higher operating temperatures.

 

If by chance if this is what the mechanic did it's possible the rings butted up, broke or worse did some cylinder damage.

 

Don't ask me how I know this.

 

Full article and credits.

What’s the Worst that Could Happen?

“If the top ring is gapped too small, when it expands the ends will run into each other,” DiBlasi continues. “As the engine heat-cycles back and forth through its maximal temperature, the top ring expands and contracts. If the gaps are too small, the top ring ends will run into itself. Since the ring has nowhere to expand at this point, the outward force applied to the cylinder increases.

 

This added force introduces even more heat and the ring expands further. Once that happens, catastrophic failure will occur rapidly as it is a continuous cycle of more heat, more outward pressure, and nowhere for the ring to expand into.”

 

If that sounds bad, it is.

 

The increased force to the cylinders starts to hold the piston tighter to the cylinder wall,” DiBlasi explains. “This added resistance, in conjunction with heat starts to soften the piston. It first will start to pull on the ring grooves and lands, spacing them further and further apart.

 

Next, the lands grow excessively in diameter due to the heat they are seeing, as the rings can no longer adequately pull enough heat away from the piston into the water jackets.

 

At this point, the top land, perpendicular to the pin axis, will be flattened out as it grows with excessive heat. In extreme cases, the top of the piston is ripped completely off the part.”

Edited September 18, 2020 by bcgold

[chasdrng 5]

18 hours ago, Tractorhead said:

Hi an  to 

Thanks Tractorhead ,

The young man that did the work seems to know what he's doing and we can't keep his cards on our counter and have nothing but good reports from customers how ever he did say he's never worked on this type of motor before. Can you explain how to tell the correct direction to install the rod please? Someone else said the same thing and said the rod & cap have holes but my guy said the only hole he saw was in the cap. Using the carburetor as a reference where should the holes be closest to carb or opposite end? Thanks Again for responding.

 

 

[chasdrng 5]

I don't see anywhere to respond to each question can someone tell me how? lol

The reason I had the new rod, piston & ring replaced is because it was using oil & smoking but ran good.

I ask about the ring gap and he said it was fine.

I started the engine and it ran fine for 2 or 3 minutes before everything started messing up.

He has tore the engine down again looking for what happened and said the ACR springs are both attached but he will try to readjust them to try to make sure they are working right.

16 hours ago, Achto said:

Thanks Achto It started fine the first time I started it? Yes battery cables are correct & I made new ones.

If it spins free with the spark plug out, it may be that the timing is off. If it is trying to fire too soon before the piston reaches top dead center it would stop the rotation.

 

First check to see if your battery cables are installed correctly. If they are reversed it could cause this issue. Not questioning your ability but mistakes happen.

Check the fly wheel position and key.

 

[bc.gold 3,406]

 

The oil hole in the connecting rod cap leads first into the oil.

 

[chasdrng 5]

3 minutes ago, bcgold said:

 

The oil hole in the connecting rod cap leads first into the oil.

 

 

[chasdrng 5]

The hole looks to be in the center sorry I'm still confused

[bc.gold 3,406]

3 minutes ago, chasdrng said:

The hole looks to be in the center sorry I'm still confused

 

The oil hole drilled on an angle. this hole must dip into the oil before the extended dipper does which is designed to splash oil onto the upper moving parts of your K181.

 

If by chance the connecting rod cap was installed backwards this would cause the engine to lock up.

 

[chasdrng 5]

Ok so it forces the oil into the hole & up inside everything and if it backwards it doesn't get oil inside !

thanks I'll pass this along to the guy.

[953 nut 61,049]

Here is a picture of an actual Kohler connecting rod. The hole is offset from the dipper and should face the camshaft when installed.

[chasdrng 5]

Just want to thank everybody for your advice.  I got it back and finally got it fired up after figuring out the NEW fuel pump isn't working now for some reason.  I took it off  and looked at everything and reinstalled it but still not pumping.  I had a tank hooked to it up high for gravity feed just to make sure it ran this time. He said he didn't find anything wrong but I'm thinking the rod cap was backwards because I don't hear any squeals and it didn't get hot like last time and I've started it several times with no problems.  I'm sure I'll have more questions like how many volts should it be putting out of the rectifier and where di i hook that wire to keep the battery changed.  Lol

Thanks again guys !!

[chasdrng 5]

Oops didn't mean to attach the photo and couldn't delete it.  

[bc.gold 3,406]

46 minutes ago, chasdrng said:

Just want to thank everybody for your advice.  I got it back and finally got it fired up after figuring out the NEW fuel pump isn't working now for some reason.  I took it off  and looked at everything and reinstalled it but still not pumping.  I had a tank hooked to it up high for gravity feed just to make sure it ran this time. He said he didn't find anything wrong but I'm thinking the rod cap was backwards because I don't hear any squeals and it didn't get hot like last time and I've started it several times with no problems.  I'm sure I'll have more questions like how many volts should it be putting out of the rectifier and where di i hook that wire to keep the battery changed.  Lol

Thanks again guys !!

 

 

If the connecting rod cap was installed backwards as you suspect along with an audible squealing from being starved of lubrication it's possible the rod was damaged, with scoring on the crankshaft journal.

 

What usually happens to aluminum connecting rods is metal transfer onto the crank journal, this is the reason you could not fully rotate the engine a full 360 degrees, the inside of the connecting rod the undamaged section was binding on the metal transfer which had welded itself to the journal.

 

If this is the case I would expect a short life for this engine, have it examined by a professional or do the work yourself.

 

 

 

 

[953 nut 61,049]

10 hours ago, chasdrng said:

I'm sure I'll have more questions like how many volts should it be putting out of the rectifier and where di i hook that wire to keep the battery changed.

The AC voltage from the engine to the rectifier should be around 30 -36 volts AC at full throttle. The DC output of the rectifier will range from 13 to 14 volts DC. The wire from the B+ terminal of the rectifier should go to the "R" terminal of your ignition switch. The rectifier will not read any DC voltage unless it is connected to the battery through the ignition switch.

[peter lena 9,348]

chasdrng , glad you got it going, that fuel pump issue could be anywhere from tank to carb , if you are dealing with old lines, filter , tank debris. something i have done is set up a gallon jug with gas and short line it to the fuel pump , that way instead of adding to the start /run issue , you have eliminated it. that will also let you run in the engine ,at a quick idle and do a carb reset, i always add seafoam to my fuels to regularly clean out the crud. use clear vinyl fuel hose , as it does not break down like rubber hose , also a new fuel filter , use the " squeeze clamps " on hose , they work very well . set up your line routing  so its smooth and protected and secured well . while you are at it THOROUGHLY LUBRICATE BOTH YOUR CARB CONRTOL CABLES . they should operate very smoothly and easily . let us know how you are doing , pete 

[chasdrng 5]

15 hours ago, peter lena said:

chasdrng , glad you got it going, that fuel pump issue could be anywhere from tank to carb , if you are dealing with old lines, filter , tank debris. something i have done is set up a gallon jug with gas and short line it to the fuel pump , that way instead of adding to the start /run issue , you have eliminated it. that will also let you run in the engine ,at a quick idle and do a carb reset, i always add seafoam to my fuels to regularly clean out the crud. use clear vinyl fuel hose , as it does not break down like rubber hose , also a new fuel filter , use the " squeeze clamps " on hose , they work very well . set up your line routing  so its smooth and protected and secured well . while you are at it THOROUGHLY LUBRICATE BOTH YOUR CARB CONRTOL CABLES . they should operate very smoothly and easily . let us know how you are doing , pete 

Fuel pump is new and only has about 3 minutes total time. I have all new fuel lines and every can of gas I bring home gets Sea Foam. In my store we sell more Sea Foam than Lucas or anything else it's great stuff !!

[Tuneup 1,452]

I was going to respond to your original post, wondering if there was oil in the engine. Acted as if....  Yeah, if it started to make noises and smoke out the vent, there is a serious lubrication issue. I would pull the pan and then the rod cap and check it and the crank journal for piece of mind. Ring gap was the other consideration. These are tough birds and you stopped it before something serious happened. The shop's admission that he'd never worked on one of these was eye-opening and a walk-away moment for me. Good luck!