JD z425 w/ B&S engine white smoke issue

Just took our JD in to the shop 4 months ago to have a throttle valve replaced to the tune of $600 when all said and done. Recently, this mower started blowing white smoke from both the engine and muffler after running for awhile. It starts out a little at first, then gradually smokes more....no noticeable engine loss or problems other than the smoke. When I first noticed it, I could see oil slowly dripping on the muffler, causing the smoking there. There is dirt/oil buildup between the muffler and engine block, but when I cleaned it off and ran again, looking for leaks, I didn't see any, not even on the muffler like before. I plan on changing oil, fuel/fuel filter, and spark plugs first, but does anyone else have experience or suggestions that a moderate diy'er can do? Trying to keep it out of the shop again if possible....Thank you in advance

*please see lower post w/pics showing oil leak out valve cover and inside after sitting

Engine Model: 44L7 77 0134 G5
23 HP 724cc
JD Turfguard 10w-30 oil

tsmurphygirl said:

Just took our JD in to the shop 4 months ago to have a throttle valve replaced to the tune of $600 when all said and done.

Click to expand...

No idea what was done for 600 dollars? Throttle valve is around a 10 dollar part or the complete carburetor 170 dollars. It looks like I don't get enough pay for my work?? That being said it sound like either a oil leak or the engine is burning oil. What are you using for oil?

I agree; they charged $500 for labor(cleaned carb, fuel tank/line, spark plugs, oil filter).....this is after I told them I already changed all that out and cleaned the fuel tank/line/filter myself. Not happy with them to say the least and the reason I am trying to tackle this myself and use them as a last resort. Wish there were more like you around here. At any rate.....I just went out and took another look at it and there is fresh oil leaking from the valve cover and down the muffler, this is after sitting. So I took off the valve cover and there is clean oil all over in there. The air filter is still clean, no oil there and no oil on spark plug. Use the JD Turfguard 10w-30 oil

tsmurphygirl said:

I just went out and took another look at it and there is fresh oil leaking from the valve cover and down the muffler, this is after sitting. . . Use the JD Turfguard 10w-30 oil

View attachment 27797

View attachment 27798

Click to expand...

So you have oil leaking from the valve cover. Buy a new valve cover gasket, install, and toque bolts to specs. If the valve cover is made of plastic you might want to replace that also? Once you get that done and if it is still smoking (not leaking) you might try a different weight oil. You are using 10w30 and you might try SAE30. Start with the smaller cheaper thing first. Buy your parts for the engine not John Deere or you will pay a lot more for your parts so it seems you are finding this out the very hard way (ouch :frown

There is one JD part you should buy however, the full service manual.
Armed with this book, if you can work out which hand is left & which hand is right you will be able to dissasemble the mower right down to the last nut & bolt then reassemble iy with your eyes closed.
Seriously the JD service manuals ar worth the extra they charge for then because they are written for Joe Public, not greasy Joe the mechanic.
We will be here if you get stuck.
And if all else fails then either take your mower to a mum & dad repair only workshop or a JD dealer.
If the $ 600 came from a JD dealer then send it into JD's head office with a "please explain".
While not as pedantic as small family companies, JD does take customer service & satisfaction quite seriously.
They stipulate the chargeable hours for each & every job and come down like the proverbial ton of bricks on dealers who profiteer.

Thank you both. The valve cover is metal, not plastic. I am going to get a new cover gasket and will also try the SAE30.

Yes, the $500 labor was from a JD dealer. Apparently, the guy who did the work was not the one I originally talked to and gave all the details. I am definitely going to get the service manual. I grew up with a dad and brothers who tinkered, so I come by it naturally I suppose. But, I also know when to admit defeat; and when I have a very expensive lawn mower, there are some things I just don't want to chance.

I will try the simple first and hopefully that will work, until the manual arrives at least. Thank you all and I will try to update

bertsmobile1 said:

There is one JD part you should buy however, the full service manual.
Armed with this book, if you can work out which hand is left & which hand is right you will be able to dissasemble the mower right down to the last nut & bolt then reassemble iy with your eyes closed.
Seriously the JD service manuals ar worth the extra they charge for then because they are written for Joe Public, not greasy Joe the mechanic.
.
.
If the $ 600 came from a JD dealer then send it into JD's head office with a "please explain".
While not as pedantic as small family companies, JD does take customer service & satisfaction quite seriously.
They stipulate the chargeable hours for each & every job and come down like the proverbial ton of bricks on dealers who profiteer.

Click to expand...

Two things here, You don't need to spend a 100 dollars for a service manual to replace a valve cover gasket or change your oil. The next thing is you are wasting your time with the JD head office. Things must be a lot different in Australia then here in the great USA. Oh by the way a service manual is wrote for the professional mechanic not Joe public. Just two different opinions here so take it as you like.