kohler k341 wheel horse c161

[Stormin 4,458]

  All this is familiar. Except for the engine stripping, it sounds just like my C-81. Idles really nice, but open the throttle........   One or two things raised on this topic, which have not been tried, will be soon. Maybe even tomorrow.

[HeadExam 1,783]

I wasn't trying to criticise all your hard work, but it would seem risky to get the engine down to that state and not mic and bore the cylinder. I would hate for you to get it running like a top, only to have the bottom of the skirt blow out, or the balance gears fly off. It would also seem like a lot of work to do this and then take it apart again to rebuild, but hey it is not my labor, only trying to give a little advice from someone that has been down that rode, some of the mistakes made by me due to inexperience, some made by a "trusted" mechanic. I guess I should have considered you might be on a tight schedule in repairing the engine. Best regards

[Stormin 4,458]

I don't think anyone thinks your being critical, Alain. A lot of good info in what you've said. Thanks.

[C-101plowerpower 548]

might be a silly question, but have you got the condenser hooked up to the wrong terminal perhaps? i've had my coil and condenser of when i painted the engine then hooked it up again but got the condenser on the wrong terminal. it would idle pretty damn good but as soon as you touched the throttle pop fart blurgh 

[Stormin 4,458]

Now there's a thought Koen. That's something I'll be checking tomorrow.

[Wristpin 400]

For all matters K series, Mike Hitchins

www.guypartsandservice.co.uk

[bubbalove 54]

well I have checked and the condenser was on the wrong side but when I put new coil on I just copied what was there already fired the engine up runs but poorly re checked the timing spot on to the static test struck her up again sweet as a nut no revs give her some revs pops bangs jumping again fine tuned the carb still the same

1 thing that I have noticed with the head off also looking at the timing marks on the fly wheel is that the "S" on the fly wheel going in a clockwise motion is before top dead centre meaning that the spark occurs just before top dead centre is that right ????

if it was to fire on tdc or just after would that not help push the cylinder back down ???

[C-101plowerpower 548]

the fireing just before tdc is right

[Stormin 4,458]

  Ok. Had a look at the connections on my C-81. All ok. Now although I have swapped carbs, coils, condensers in the past, I decided to swap over the condensers from C-125 to C-81. 

  Fired up the 81 and it revs like a good 'un. No spitting and dying now. All seems ok.  

  Put the 81's condenser onto the 125, fired up and expected the high revs problem to be transferred to the 125. Err! No! High revs ok.

 This proved, I hope, that the condensers are ok. So my conclusion is that the condenser on the 81 was not earthing properly. 

 I'll give them both a run out later and see how things go.

[bubbalove 54]

good luck hope they both run lovely for you im washing my hands and packing up for the weekend its the mrs birthday Tuesday so we going on our boat for the weekend
HAVE A GOOD WEEKEND LADS THANKYOU FOR ALL YOUR HELP THIS WEEK IM VERY GRATEFULL   :bow:        

[C-101plowerpower 548]

have a good weekend away with the wifey Tom

[bubbalove 54]

well I've had a play today and after putting exhaust back on and leaving her running on tick over she purrs like a kitten going from full revs to idle she might pop now and again but nothing like she did when I started so I have got to admit that it must of been either the condenser on the wrong side of the coil or a bad earth combined with the carb not set right but I think im finally there with her. now I no what im doing there will be parts ordered to do a full rebuild been onto a local guy to me and he said he can either re sleeve and go original piston or re bore and go oversize piston what do you guys suggest                   

[HeadExam 1,783]

well I've had a play today and after putting exhaust back on and leaving her running on tick over she purrs like a kitten going from full revs to idle she might pop now and again but nothing like she did when I started so I have got to admit that it must of been either the condenser on the wrong side of the coil or a bad earth combined with the carb not set right but I think im finally there with her. now I no what im doing there will be parts ordered to do a full rebuild been onto a local guy to me and he said he can either re sleeve and go original piston or re bore and go oversize piston what do you guys suggest                   

Unless the cylinder is over .30 thousandths out there is no need to sleeve, as sleeves are generally done to engines that have been bored multiple times or have excessive wear. The sleeve route can also be more expensive as the cost of the sleeve has to be considered. Most engines on initial or first time rebuild are .20 thousandth, or 30 thousandths at most. I would go the the bore and oversize piston rings route. Do not forget the crank surface reface and order a under size connecting rod or rebuild the surface to standard The crankshaft is often overlooked and this will be a source of engine failure if not properly addressed. Finally end play on the crank should be carefully checked and brought to specs if not within tolerances. I'll let someone else chime in about valve and cam issues as I know many more are more familiar with these.. 

[Anglo Traction 1,016]

I believe you have an untouched standard original bore. As Alain suggests, I would also go for a re bore and hone.

I would also go to +0.020" depending on any major scoring and to give the person doing the job more 'meat' to remove and finish hone to a good clearance measurement.

Kohler appear to restrict limit of re-boring to 0.030" , so It could still have another in the future.

The other reason for 0.020" size is that you'll need to purchase a new Piston etc in advance of presenting it for re-boring for the person to accurately finish the bore to the minimum clearance spec of that new piston (they can vary in dimensions slightly) . 

It is likely the Crank will need a regrind to 0.010" under as well.

I had both done and really pleased with the job and the price they charged ( back in 2012)   

 

Point to note- There are 2 types of Piston - 'C' and 'D'. You need to ID which type you have and specify it when ordering, or make sure you obtain the equivalent.  

The reason is that the engine was built with either a statically, or dynamically balanced Piston/Rod and Crank.

The new Piston/Rod must weigh virtually the same as the original, more so if you have removed the Balance Gears and not replacing them. (keep and weigh your original Piston/Rod & Pin).

This is one of the reasons why engines may vibrate more when the B/Gears are removed.

Balance Gears are installed to reduce the vibration caused by Lateral movement of the Crank (front to back direction) as the Crank is balanced for vertical movement.

If the new Piston etc is heavier/lighter, the imbalance will also return to the vertical movement.

A few grams difference should be bearable. 

 

One point on the Cam Shaft is that the Pin/Shaft it rides on goes back in to a specific depth. It may also be worn on the upper face due to downward pressure from the Valve Springs. As most of the pressures are lateral and downwards, you could refit it with the worn face down .

Camshaft End float shims are the same size as the Balance gear Shims so keep them for spares if they're good.

Valve Guides/Stems have finite wear limits. Check them to avoid problems later.

All the Specs, clearances and limits are on page 8 of the K Series Service Manual. I printed that page off for the Re bore Service Staff when I had mine done and I have a copy nailed to my garage wall .

 

Lastly, If your original Carb is a Kohler type, don't junk it, They can be saved with a proper rebuild to the same spec that some here will recall I did on all mine (#26 on K301's)....here's a link to what I did-

http://www.wheelhorseforum.com/topic/42411-new-life-for-an-old-26-kohler-carb/

 

Regards.

[HeadExam 1,783]

I believe you have an untouched standard original bore. As Alain suggests, I would also go for a re bore and hone.

I would also go to +0.020" depending on any major scoring and to give the person doing the job more 'meat' to remove and finish hone to a good clearance measurement.

Kohler appear to restrict limit of re-boring to 0.030" , so It could still have another in the future.

The other reason for 0.020" size is that you'll need to purchase a new Piston etc in advance of presenting it for re-boring for the person to accurately finish the bore to the minimum clearance spec of that new piston (they can vary in dimensions slightly) . 

It is likely the Crank will need a regrind to 0.010" under as well.

I had both done and really pleased with the job and the price they charged ( back in 2012)   

 

Point to note- There are 2 types of Piston - 'C' and 'D'. You need to ID which type you have and specify it when ordering, or make sure you obtain the equivalent.  

The reason is that the engine was built with either a statically, or dynamically balanced Piston/Rod and Crank.

The new Piston/Rod must weigh virtually the same as the original, more so if you have removed the Balance Gears and not replacing them. (keep and weigh your original Piston/Rod & Pin).

This is one of the reasons why engines may vibrate more when the B/Gears are removed.

Balance Gears are installed to reduce the vibration caused by Lateral movement of the Crank (front to back direction) as the Crank is balanced for vertical movement.

If the new Piston etc is heavier/lighter, the imbalance will also return to the vertical movement.

A few grams difference should be bearable. 

 

One point on the Cam Shaft is that the Pin/Shaft it rides on goes back in to a specific depth. It may also be worn on the upper face due to downward pressure from the Valve Springs. As most of the pressures are lateral and downwards, you could refit it with the worn face down .

Camshaft End float shims are the same size as the Balance gear Shims so keep them for spares if they're good.

Valve Guides/Stems have finite wear limits. Check them to avoid problems later.

All the Specs, clearances and limits are on page 8 of the K Series Service Manual. I printed that page off for the Re bore Service Staff when I had mine done and I have a copy nailed to my garage wall .

 

Lastly, If your original Carb is a Kohler type, don't junk it, They can be saved with a proper rebuild to the same spec that some here will recall I did on all mine (#26 on K301's)....here's a link to what I did-

http://www.wheelhorseforum.com/topic/42411-new-life-for-an-old-26-kohler-carb/

 

Regards.

Excellent Post!!! Thanks for correcting my decimal point on the thousandths and adding so much more detail, and while this may seem a lot of technical jargon and a large endeavor, the kohler singles are very simple engines that can produce a lifetime of enjoyment if rebuilt properly.