2206 engine/mower problem

[jniolon]

hi guys... newbie here - first post, hoping you can help.

I've got a 2206 tractor with a 48" mower. recently I noticed that the engine (20hp Kohler) seemed to be running harder than it should when mowing.

One of the blades was extremely hard to turn without the belt on it so I figured spindle bearings were seizing up. Yesterday I replaced all three sets of spindle bearings... regreased, reinstalled mower and it seemed to help a little but when you engage the mower it still nearly stalls the engine and is slow to come up to speed.. frustrated I parked it in shed and called it an evening

laying in bed I'm studying on the problem... if it's not the mower spindles the only other moving part is the clutch.. I didn't try engaging with no load/belt on the clutch but could a clutch start to seize up and load down the engine ??? by itself with no mower attached ???

I'm at a dead end and hope you guys can help...

tia
John

 

[dross]

John, welcome

You have idler pulleys? when you had the belt off did you spin them to make sure they were okay? That deck belt have a tightener? is it free? I'm not real familiar with this model, it's just a thought.

 

[kide]

Per the parts lookup, it uses two idlers, (tut tut, Dave..

) part number 756-3005...As Dave suggests, these can be frozen.. BTW - Welcome to the Forum!!

 

[dross]

I said "pulleys" and "them". Plurle was implied.

 

[kide]

Dave - just pullin' yer leg - the parts blowup on that deck is "interesting" compared to our older stuff...

 

[dross]

It's okay, I know they x'ed the "pulling your leg" clipart.
I went and looked at the 2206 stuff too. When they hit 40 years old and I can get one for a couple hundred I'm there.

 

[jniolon]

update on my power problem...

first I replaced all the spindle bearings... they turn easy now but didn't help the power problem
checked all the idler pullys and they all turn easily..

so I'm ruling out the deck as the problem.. on to the engine... when I engage the clutch there is no appreciable load on the engine... next to the plugs
left side looks good light brown and compression is 150 #... I'm happy
right side :-( plug is completely fouled with oil... like it's caked in between the housing and the ceramic... compression is 150 # cleaned the plug best I could and regapped... replaced in engine and it runs much better... but now I'm seeing blue smoke from the exhaust...

so I figure I was running off one cylinder... that was the reason for the power drop... now... diagnose the engine problem...

broken ring ?? but why is compression good ??
valve problem ??

enlighten me of gurus of the Kohler 20 hp twin cylinder engine... please

tia
John

 

[mgonitzke]

This doesn't explain why you have 150 psi of compression, but I think they had some head gasket issues with the Commands. Is the cylinder all oily on that side?

 

[jniolon]

haven't pulled the sheet metal off to check but when I shut it down is see smoke from that side of engine so it's probably leaking... BUT if it was a head gasket shouldn't I see low compression on that side ???

 

[dtanner]

john a. niolon

If the engine had a dead plug.you say one was wet,, well wet will leak from a head gasket. I would keep an eye on the oil level and see if the smoke clears up now that the plug is working.my .02

 

[jniolon]

I'm wondering why one plug is fouling ??? it was completely caked with burnt oil... all coked up between insulator and metal housing... I had noticed a couple weeks ago that it had used a little oil... didn't think much of it... it's ten years old... wonder what the fix might be ??? if it's just a head gasket I can probably do that... what else might it be ???

tia
john

 

[dross]

John, Rings?

 

[jdiederichs]

John, You are certain to have a bad head gasket on that side. It allows oil from the small oil return passage to be drawn into the combustion area. The gaskets are of a graphoil material and what will happen is this: a small "worm hole" develops between the oil return passage and the cylinder. Cylinder vacuum will draw oil from the return into the cylinder causing the fouled plug caked with oily deposits.

The oil return passage allows oil in the rocker area to drain back to the block. However since the gasket developed that worm hole some oil is diverted to the cylinder. A similar situation could also occur btween the cylinder and the lifter bore area, however this leak is less common than the oil return passage. Neither will often show any outward leak.

One method to prevent future failures is to avoid backfires as this stresses the head gasket material. Since your tractor has a carburetor with fuel shut-off solenoid, you must turn it off only when the throttle is positioned at 3/4- full throttle; that way no raw fuel is drawn into the engine= no backfire. No harm will come to engine as it coasts to a stop from 3/4 throttle, as the oil pump keeps everything lubed just fine.

Oh, btw, look at the head gasket when your dealer gives it to you. NEVER accept one that shows any bending or creasing, these fragile Graph-oil gaskets don't tolerate that and will soon leak at the crease.

 

[jniolon]

thanks for the nice detailed explanation Jim. Ordered the gasket kit this a.m. and it should be here Thursday... got my weekend chore planned...

any special hints or procedure for changing the gasket or is it pretty much R/R ???... thread lock ?? on the bolts or just oil lightly... any sealer on the gasket ??

thanks everyone for your ideas and knowledge... hopefully by end of weekend my Cub will be percolating properly again

john

 

[wwesterfield]

I think I am having similar problems. I just posted on my "1863 switches" topic that something is kicking in during cranking and slowing it down horribly and now the engine is missing on one cyclinder. Same fauled plug issue that you are having but not as oily. thought I heard some compression(air sound) as the engine shut off on that side. I will look at he head gasket on that side. As I stated in my other post, my 1863 was running like a top when I put it in the garage two weeks ago, I try and fire it up to mow the other day and all this stuff is wrong with it???

 

[jdiederichs]

John, The gasket (kit) includes new head bolts, which must be changed each time the head is removed. They are a shouldered "stretch" bolt design. Follow the instructions, no thread lock on threads, gasket must go on dry and is directional (note lettering on gasket) Be absoltely sure that the head bolt holes are clean, no dirt or oil in them as the bolts will not tighten properly. You can lightly oil the threads during installation.

Since the engine has hydraulic lifters, no adjusting the valves! Simply reassemble and you're good to go. Follow torque specs and do not overtorque head bolts.

I will assume it is the right hand cylinder (when seated on tractor)that failed the head gasket. Check for a good seal where the muffler pipe flange attaches to the head port; a leaking ex. gasket can overheat the area around that head bolt allowing it to "grow" and allow leakage. This is critical on all Command twins, paticularly on the RH cylinder. Your kit will include new intake and exhaust gaskets provided it is Kohler parts.

 

[jniolon]

once again Jim... thanks for the detail. It is the right cylinder.... The kit IS a Kohler kit and should be here tomorrow.. I thought I'd get to work on it this weekend but a road trip is calling my name.

from the original repair manual it says that head bolts (not studs) should be torqued in a cross pattern UR-LL-UL-LR to 200 inch #s then the opposite pattern UL-LR-UR-LL to 370 inch #s... I'm assuming that is still correct since I'm not using bolts instead of new studs/nuts... lettering on gasket goes "UP" facing the head.

after running X number of hours, should I go back and retorque or leave it alone ??

thanks again
John

 

[jniolon]

just an update to let you guys know what happened... ordered the gasket from a local cub dealer (about 30 bucks) it had a new head gasket, exhaust/intake gaskets and 4 head bolts...

the hardest part of this job was trying to remove all the baffles and sheet metal without removing the entire engine... it was a challange. But, got that done and removed the head. head was coked up bad from burning the oil but the head and piston showed no damage... cleaned up the head and block, installed the gasket and new bolts and torqued it all down... new plug and replaced all the sheetmetal..

gave it a crank and it fired right off.. mower runs so much better now with the power it had when new and I swear it's smoother and quieter.. but that might be due to my expert wrenching... job took about 4 hours but most of that was removing and replacing all the sheetmetal...

thanks for all the help... especially you Jim... you guys saved me a fortune probably...

later
john

 

[jdiederichs]

Good to see it worked out for you John! Yes, the sheetmetal ducting and stuff takes more time than the actual job. If you did it in 4 hours that is pretty darned good....

Be a careful operator on the shut downs, don't let it backfire, as that often overstresses the gaskets and it should last for many years. It helps to blow compressed air thru the ducting as well occasionally to clean out the build up clippings as that insures proper cooling of the heads.

 

[jniolon]

posted earlier but it didn't stick ????

I'm a little paranoid... everytime I use the mower afterwards I fill it with gas, check the oil, take out the air filter and clean it and the prefilter and blow out the engine compartment...

I've told my senior operator (wife) to shut it down at 1/2-3/4 throttle from now on to prevent the backfire problem... should keep the sheetmetal on for a long time...

thanks
John