How messed up is my K181?

[82Caddy 851]

Was pushing some snow with the old commando 800 (K181) when it shot a solid 2 foot flame out the exhaust stack and died.  Cranked over to have it backfire out the carb.  Figured something was wrong and that I should look at inside a building.  Pushed the tractor into my shop and did a bit of diagnosis.  Was acting like the intake valve was stuck open.  It'd blow pressure out through the carb and the exhaust. So I pulled the valve cover piece off to find this:

 

 

Have lots of other tools but I don't have a valve spring compressor tool for this and neither do any of my friends.

 

 

I'm stuck between holiday weeks so I can't get parts or tools by the weekend.   So before I go and order tools, how screwed is this motor?  Am I looking at compressing that valve spring and finagling the keepers back in place or is that valve toast and I need to find another one along with pulling the head?

 

Another sad day for the horses at my house.

[rmaynard 14,914]

The other issue that you will have is if the valve needs to be replaced, setting the gap is done by grinding the stem. However, having said that, the K181 is well worth the trouble to repair it.

[pfrederi 17,155]

Really can say much until you get the spring off Hopefully the keepers are under there some where.  But that they failed may indicate some thing is wrong with them or the valve stem itself

[Ed Kennell 35,880]

I would pull the head to decarbon and check the valve seats.  With the head off,  You can probably pull out that loose valve. and carefully slide out the spring and keeper.  At least you will know if the valve and/or keeper need replaced.  Of course you will still need the compressor to reassemble.

[82Caddy 851]

3 hours ago, rmaynard said:

The other issue that you will have is if the valve needs to be replaced, setting the gap is done by grinding the stem. However, having said that, the K181 is well worth the trouble to repair it.

 

That isn't an issue, more of an issue having the right parts on hand and not paying for shipping 2-3 times and weeks of downtime.

 

35 minutes ago, pfrederi said:

Really can say much until you get the spring off Hopefully the keepers are under there some where.  But that they failed may indicate some thing is wrong with them or the valve stem itself

 

That's what I don't know is if something happened to the valve stem, the keepers or the retainer failed.

 

9 minutes ago, ekennell said:

I would pull the head to decarbon and check the valve seats.  With the head off,  You can probably pull out that loose valve. and carefully slide out the spring and keeper.  At least you will know if the valve and/or keeper need replaced.  Of course you will still need the compressor to reassemble.

 

There weren't any odd or funny noises/smoke/etc before it died.  I was trying to avoid pulling the head just because I didn't want to but it looks like I'll be removing the head tonight.

 

Anybody have any ideas how things like this happen?

[slammer302 2,154]

more than likely you just need a new keeper for the valve spring and you will be on your way 

[WHX?? 46,829]

Use a couple of screwdrivers to compress the spring to check the stem. Santa didn't bring me that tool this year but I am pretty good at doin it with screwdrivers.   Were the keepers or any other pieces laying in there? would be possible for the keepers to come off ..say during a backfire... but unlikely... most likely a sheared valve stem. Let us know.

[82Caddy 851]

57 minutes ago, WHX6 said:

Use a couple of screwdrivers to compress the spring to check the stem. Santa didn't bring me that tool this year but I am pretty good at doin it with screwdrivers.   Were the keepers or any other pieces laying in there? would be possible for the keepers to come off ..say during a backfire... but unlikely... most likely a sheared valve stem. Let us know.

 

I did pry it up a little and didn't see anything that didn't belong in there.  I was also trying to hold a flashlight, see in that space and use the screwdriver so it is very possible I missed something.  No sign of the valve keepers flying around either in that space.  Good news is there isn't really anywhere for them to go.

58 minutes ago, slammer302 said:

more than likely you just need a new keeper for the valve spring and you will be on your way 

 

Do you mean this:

or this:

 

Edited December 30, 2015 by 82Caddy

[WHX?? 46,829]

Well now thats bizarre that they weren't in there. The keepers (your bottom pic) are too big to go down the drain hole (the small hole you see in back) to the crank case.  Look real careful and inside both valve springs in case they are wedged in there. I would think even if they got chewed up up by valve gear some pieces would still be there. The retaining washer, your top pic is what wedges the tapered  keepers to a groove in the valve stem. Valve spring pressure is all that holds them in ther. Check the breather tube on the off hand chance see if they didn't try to get blown out there. Slammer might be right and all you need is some keepers. Would be nice to know what happened to the old ones tho and I would endeavor to look for them.

[Ed Kennell 35,880]

I think you will find the two collet pieces  inside the domed washer piece.   The inside lip is probably worn or sheared off.

[82Caddy 851]

6 hours ago, ekennell said:

I think you will find the two collet pieces  inside the domed washer piece.   The inside lip is probably worn or sheared off.

 

We have a winner...

 

I decided against pulling the head for now since I found the valve keepers smashed around the pushrod when i lifted the valve spring with some screwdrivers.

 

 

Guessing the valve keepers aren't supposed to be smooth on the insides.   From the looks of the valve, it appears to be alright so I'm thinking I lucked out and only need another pair of valve keepers.

 

 

Thoughts on replacing the valve keepers and seeing if it runs?

[Howie 882]

Put some new ones in there and try it.It not like an overhead valve engine where the piston would have hit the valve.

 

David

[82Caddy 851]

Ordered a set of valve keepers and the small engine spring compressor.  Hoping to have everything here by early next week and be back up and running.  

 

Up next is to sort out why the K341 on the D160 won't start but that's a different issue for another thread.

[Ed Kennell 35,880]

Yeah, put  the new keeper in  and check the clearance on both valves.  If OK,  light her up.    Then give us some symptoms on the sick D160.  

[Shynon 7,435]

 I would check the keepers on the other valve too. You may have worn ones on that side also. I have never seen this before, makes me wonder what would cause this.

[82Caddy 851]

This engine was rebuilt 8-10 years ago by a local small engine shop. It was used for a summer to mow and was retired at that point due to lack of throttle control (either idle or wide open).

 

When I bought my house last fall I decided to revive the old horse as a mower/snow mover since funds were tight and the driveway is far too large to shovel efficiently.  Turns out the governor was adjusted incorrectly and throttle linkage was installed wrong. Fixed that and have had minor issues (mid adjusted points, broken wires) but nothing major until this. 

 

Once I get that valve spring tool I'll check the other valve keepers just for good measure. 

 

The K341 just won't run. Has new fuel filter/lines and fuel (verified by removing fuel line at carb and cranking engine over), carb cleaned, points adjusted to .02, has a nice spark on new plug. It'll sputter for 1-2 revolutions. Randomly backfire in the exhaust with a flame. I put all new battery cables and a few extra ground cables on just for good measure. I just can't get it to run and I'm out of ideas on it. 

[Ed Kennell 35,880]

You need compression, fuel, and spark to make the 341 run.  Let's assume you have compression.   Will it run if you hand feed (squirt) fuel into the carb ?  If it does, you still have a carb problem.   If it does not, you still have a spark problem or possibly no compression (another bad valve keeper).     Have you checked compression and/ or the valve clearances?

[82Caddy 851]

Have not checked anything with the valves. Compression tester was returned this morning and is on the to do list for this evening. 

[953 nut 51,802]

28 minutes ago, 82Caddy said:

This engine was rebuilt

My guess would be that the keepers were never properly seated and finally jiggled loose. Valve stem looks good, go for it.

[82Caddy 851]

3 hours ago, ekennell said:

You need compression, fuel, and spark to make the 341 run.  Let's assume you have compression.   Will it run if you hand feed (squirt) fuel into the carb ?  If it does, you still have a carb problem.   If it does not, you still have a spark problem or possibly no compression (another bad valve keeper).     Have you checked compression and/ or the valve clearances?

 

Compression was as follows 48, 50, 52 psi on a cold (not run) engine.  I feel like that is really low,.

 

Did not check valve clearances, my feeler gauge has gone MIA.

 

Will run if I squirt gas into the carb.  Looking like I'm going to tear this thing apart and see how bad the piston walls look and rebuild it.  Not what I wanted to do  

[Shynon 7,435]

16 minutes ago, 82Caddy said:

Compression was as follows 48, 50, 52 psi on a cold (not run) engine

Kohler has automatic compression release, you need to do a leakdown test.

[82Caddy 851]

I don't have a leak down tester. Maybe I'll see if it is a loan-able tool from a FLAPS (friendly local auto part store)  near me 

[Ed Kennell 35,880]

5 hours ago, 82Caddy said:

 

 

 

 

 

Will run if I squirt gas into the carb.  

Remember my other post above....If it runs when you squirt gas directly in the carb,  You have a carb problem.     Fix or replace the carb first to get it running, then rebuild the engine if that's what you want to do.

[82Caddy 851]

Are the 40$ ebay carbs any good?  I've been into this one twice with no apparent success.  Once for a leaking float bowl gasket and another for the needle sticking.

[Shynon 7,435]

Make sure you get the one that is threaded American and has the correct choke linkage, I think they are about $75. How much throttle shaft play do you have?

Edited January 1, 2016 by Shynon