Toro Zero Turn smoking

[Cboy553]

https://www.jackssmallengines.com/jacks-parts-lookup/manufacturer/toro/riding-products/2004/74350-17-42z-timecutter-z-riding-mower-2004-sn-240000179-240999999/cylinder-head-assembly-briggs-and-stratton-31f777-0162-e1

cylinder head complete ... $213.xx .... lots less than $1250. If the customer wants it to work properly and will not stand for a slight puff of smoke on startup, then it will cost at least this much to replace the head. Doing the valve stem seal(s) may reduce the puffing. An alternative is to have the valve guides reamed or drilled and new guides pressed into the cylinder head. Then ream the guides to the proper size to fit the valve stem diameter. All of that labor will likely be more than a new cylinder head.
A second alternative, or third.. fourth... would be to find a used head that was in better shape.
I am not on the clock, so I would have taken the head apart when I had it that far, and checked the condition of the valve seats, the fit of the stem to the guide, and certainly replaced the seal. If you want no smoke, you will have to do the 'rope' thing, or remove the head and refurbish is or replace it.
I see no alternatives...
tom

Well that’s what I’ll do then. Replace the head.

 

[grumpyunk]

Note: I did NOT check any source for availabiltiy, nor did I do ANY price shopping. That is beyond my level of interest & knowledge.
tom

 

[Cboy553]

Note: I did NOT check any source for availabiltiy, nor did I do ANY price shopping. That is beyond my level of interest & knowledge.
tom

It’s all good though. I think the boss knows it’s not the honing. He suggested it was rings and was wrong. He probably trying make it look like I messed it up. But I don’t care. I have the green light on the head replacement from customer. So that’s that.

 

[sgkent]

typically consistent oil smoke on start up on an engine is oil leaking down from valve guides. Either worn or seals (if any) worn. Make sure the breather is open. I had a shop assign me a job to replace cam seals on a twin OHC engine. The shop foreman sold the guy on the new cam seals and gaskets. I did the work, and it was back in a day. No one told me what the guy's actual complaint was. He was complaining about oil leaks and smoking. Once I knew what his complaint was took about 5 minutes to clean the breather screen that was plugged.

 

[Cboy553]

typically consistent oil smoke on start up on an engine is oil leaking down from valve guides. Either worn or seals (if any) worn. Make sure the breather is open. I had a shop assign me a job to replace cam seals on a twin OHC engine. The shop foreman sold the guy on the new cam seals and gaskets. I did the work, and it was back in a day. No one told me what the guy's actual complaint was. He was complaining about oil leaks and smoking. Once I knew what his complaint was took about 5 minutes to clean the breather screen that was plugged.

That’s interesting I’ll have to look into that as well then. Thanks man

 

[doug9694]

I work at a rental shop and just tore down a zero turn replaced rings and head gasket. Was burning oil badly like a quart an hour. Well now it smokes on start up for about a minute. Well I realize I had oil in the carb so I let it run half an hour. Anyway it still smokes on start up. Any ideas thank

May be breather valve. Try temporarily disconnecting the breather tube. Or may be a warped head allowing oil to get sucked in.

 

[RGSERVICES]

I work at a rental shop and just tore down a zero turn replaced rings and head gasket. Was burning oil badly like a quart an hour. Well now it smokes on start up for about a minute. Well I realize I had oil in the carb so I let it run half an hour. Anyway it still smokes on start up. Any ideas thank

if on start up : valve stem seals, if smokes a short while after start up (usually increasing) : oil control ring / wiper ring. that is the general rule, what colour is the smoke? it maybe fuel and not oil at all! the float needle may not be sealing fully which would allow fuel to run into the cylinder (via atmospheric pressure / gravity) so effectively you are starting a slightly flooded engine - if that were the case the smoke would clear very quickly, the question is what colour smoke have you got black = fuel, blue/grey sometimes referred to as white = oil

 

[Cboy553]

if on start up and clears : valve stem seals, if from start up and constant (usually increasing) : oil control ring / wiper ring. that is the general rule, what colour is the smoke? it maybe fuel and not oil at all! the float needle may not be sealing fully which would allow fuel to run into the cylinder (via atmospheric pressure / gravity) so effectively you are starting a slightly flooded engine - if that were the case the smoke would clear very quickly, the question is what colour smoke have you got black = fuel, blue/grey sometimes referred to as white = oil

White.

 

[RGSERVICES]

White.

does it clear after start up or stay the same?

 

[Cboy553]

customer states the mower was parked for two years then when ran it started smoking. He says when oil gets down low enough to the add mark on dip stick then won’t smoke