YTH18542 Briggsandstratton motor belching white smoke

HusqvarnaRider

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Greetings Ya'll,

I have a Husqvarna riding mower Md. YTH18542 which we bought new, back in May 2022

Sure enough, 4 days after the warranty expired, during my first "Intentionally Slow moving cut", for the lawn, which I hadn't been able to get to, due to the abnormal rainfall, here in Ohio, the grass, averaged approx. 12" high, & I set the deck at it's highest level.

The mower, would occasionally, "under a load", begin belching a white, somewhat grayish smoke, & spraying oil, from around the dipstick. There was not any "Metallic noise", that would suggest a broken rod, piston, etc.

I stopped the mower, popped the hood up, & saw where it had apparently been spraying, from around the dipstick, & I then let the motor cool off. I cleaned off the oil that had sprayed out,so as to verify it's true source, & then checked the oil dipstick. The oil level was down approx. 2 oz, & I filled it back up to the required level. I then started the mower, & did not see any smoke. I then rode it around for about 5 minutes, & still did not see any smoke.

I then engaged the Mower Deck, which did produce a cloud of White Grayish smoke, but,... That quickly dissipated, & the smoke being ejected via the exhaust actually reduced to a point, where it was not noticeable. Occasionally, I would have to stop, & pick up branches that had fallen from trees, & when I would re-start the Mower, it would belch out the White, somewhat grayish smoke, but then it would clear up. I then finished mowing our two acre lot.

The Original Motor, on this Mower is a "Briggsandstratton" 18.5 HP, 540cc, Md.# 33R777-0005-G1 (586306801) 96045005901, 2020-10/ Ser.# 21111119314332.

I wanted to get, "Technician Tips" hoping that this problem is minor, as well as pricing for repair, & all related data, as well as the cost of a New Motor, which I've been told by a Briggsandstratton Rep is a Md.#33S5877-0019-G1 and that it is a "Direct Replacement", with a Two Year Part Warranty.



Over this weekend, I could find many sources for "parts" for that motor, but not the motor itself, And, as I suspected, today I learned that the motor, went out of production in May of 2023!

Here's my main reason for this post,... Are there "Simple Problems", that could be easily corrected, that would also be similar to a "Leaking Head gasket", or "Piston issue"?

I Fully realize that the Motor would have to be "Physically Diagnosed", in order to determine the precise problem, but,.... Rather than hauling the mower to a shop, for Diagnosis/Repairs, which easily could quickly add up to several hundred dollars, which I was told this morning, from three different shops,... I want to see if it's just a "Simple fix". And, collectively all 3 shops are now swamped with work, with the "Wait time" averaging from 5 days to 3 weeks. Another problem is that any repair to the motor, would only have a "Warranty" that would be from 30 to 90 days, which is why I'm thinking of replacing the motor, with the Revised Motor, and installing it myself.

Since I do HVAC/Electrical/Refrigeration, I'm imagining that replacing the motor, should not be as complicated as installing a New 20 HP Refrigeration Compressor, but then again,... I could be wrong.

I'd appreciate any suggestions, "Tips & Tricks", etc.

Thank You !

David
 

ILENGINE

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Your symptoms are indicative of a head gasket that is starting to fail They will fail in the narrow area between the cylinder wall and the cavity where the pushrods are located. So it will pressurize the crankcase when the piston goes up as well when the plug fires to start the next cycle. Not a bad repair but can take up to a couple hours depending on condition of head and cylinder flatness. Since both are subject to warpage. So ballparking a couple hundred. New engine list at $808
 

slomo

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depending on condition of head and cylinder flatness. Since both are subject to warpage.
True so true.........

Must lap the head and block area where the head gasket sits. Unless you like doing it all over again later.......
 

HusqvarnaRider

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Thank You for quickly replying ILENGINE, & siomo.

Is it common for a repair like that to only have a 30 to 90 day Warranty? I'm thinking that paying approximately 60 to 75% of the cost of a New Motor, with such a short warranty, that replacing the motor would be the better route.

Also, here in this Forum/Website, or even on YouTube,etc. is there Technical Data available that would help in the process of replacing this motor.

If YouTube is as "Rich" in data about Mowers/ Engines, etc., as it is in HVAC/Electrical, & Refrigeration, then I'm assuming that I could DIY this motor replacement
 

Auto Doc's

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Teryl Fixes all has a bunch of engine swap videos. His comedic approach is not quite understood by some folks, but he is playing into the common belief that mechanic are just stupid hillbilly types. In reality the guy really knows his small engine work.
 

ILENGINE

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Thank You for quickly replying ILENGINE, & siomo.

Is it common for a repair like that to only have a 30 to 90 day Warranty? I'm thinking that paying approximately 60 to 75% of the cost of a New Motor, with such a short warranty, that replacing the motor would be the better route.

Also, here in this Forum/Website, or even on YouTube,etc. is there Technical Data available that would help in the process of replacing this motor.

If YouTube is as "Rich" in data about Mowers/ Engines, etc., as it is in HVAC/Electrical, & Refrigeration, then I'm assuming that I could DIY this motor replacement
Most shops will only offer a 30 day warranty on their work. And parts are normally warrantied through the manufacturer for 90 days in some cases, and 1 year in others.
 

HusqvarnaRider

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Teryl Fixes all has a bunch of engine swap videos. His comedic approach is not quite understood by some folks, but he is playing into the common belief that mechanic are just stupid hillbilly types. In reality the guy really knows his small engine work.
:LOL: Is he the guy with the Fake Buck Teeth & Long hair? If do,... He's been very helpful for me, on my chain saw,weed eater, tiller, & the 'Used Mower" that I had.
 

HusqvarnaRider

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Most shops will only offer a 30 day warranty on their work. And parts are normally warrantied through the manufacturer for 90 days in some cases, and 1 year in others.
That's Sad, & somewhat Shocking, at least when comparing the Warranties expected from My Work.

The Majority of Parts be it HVAC/Electrical, &/or Refrigeration, are expected to have at least a One Year Part & Labor Warranty.

LOL! I worked on a furnace several years back at a shop that did repairs, & the Owner tried to get me to give him a "Lifetime Warranty" on his new gas valve, which didn't happen.

I've even had Brand New Parts, break down within months of their installation, & had to honor the "One Year Labor Warranty", but,..... When I notified the Distributors about the failure of the Parts, the bulk of the time, they reimbursed me for my labor.
 
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