Smoking motor

Denny W Smith

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I am glad to find this site as I have lots of questions on what route I should go. I posted this a few days ago but in the wrong location I think.

I have roughly 30 acres to mow most of which is done by a tractor and a 6' bush hog. About 4 or 5 acres I am mowing with my Exmark Lazer Z AS Model # LZA27KC604, S/N 879852 with a Kohler Command Pro 27 engine, Model PS-CV740-3119, S/N 4012800281. I did mow the entire 30 acres once last fall before winter with this mower. This is my first and so far only experience with a zero turn mower. I purchased it at auction in Aug 2021 with 1279 hours on the meter. I am sure it was operated previously by a landscape contractor. It now has 1370 hours on it and this past week the engine has started to lose power under load and is pumping blueish white oil smoke out the exhaust. I am assuming it has bad valve seals or rings (I am not a small engine mechanic). A quick online search indicates a replacement engine is running about $3k. Otherwise the machine is in decent shape I think. The deck is good. My question is should I invest more money into it? What kind of hours should I expect from the drive motors or am I looking at rebuild/replacing these soon?
In comparison to repairing I could really use a 72" deck machine perhaps with a more versatile suspension system to handle the rough terrain better (property was timbered about 10 years ago and is still rough in places) possibly a Ferris ISX3300 ($18k ouch!) or something comparable with a more robust suspension system.
Should I replace the motor and sale/trade it? Buy a finish mower for the tractor instead?
Any thoughts or suggestions would be appreciated. Also, does anyone know the year of this mower via the model or serial numbers?
Thanks in advance for any replies.
 

sgkent

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30 acres is the key statement here.
 

Tiger Small Engine

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30 acres is the key statement here.
You have three basic options:
1) Keep a close eye on the oil and add as needed until power diminishes to the point of rebuild/repower
2) Repower with new engine
3) Spend $16,000 plus on a new zero turn.
 

OldMasterTech

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The Kohler serial number is circa 2010 if I read their chart correctly.
If the rest of the machine is solid I'd repair it but for that rough terrain area I'd buy whatever attachments were appropriate and use the tractor, it'll last longer!
 

hlw49

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Is it fouling the plugs? It could be blown head gaskets. I have seen those engines with thousands of hours and still not use oil given reasonable maintance.
 

Born2Mow

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Exmark Lazer Z AS Model # LZA27KC604, S/N 879852 with a Kohler Command Pro 27 engine, Model PS-CV740-3119, S/N 4012800281. I did mow the entire 30 acres once last fall before winter with this mower. This is my first and so far only experience with a zero turn mower. I purchased it at auction in Aug 2021 with 1279 hours on the meter. I am sure it was operated previously by a landscape contractor. It now has 1370 hours on it and this past week the engine has started to lose power under load and is pumping blueish white oil smoke out the exhaust. I am assuming it has bad valve seals or rings (I am not a small engine mechanic). A quick online search indicates a replacement engine is running about $3k.
• First of all, I proabably would have shied away from a used motor from a landscape crew with over 1000 hours, unless it was from a dealer with a warranty. Especially buying from an auction where you don't know the history, don't get the maintenance records, and can't contact the PO. You basically bought "a pig in a poke". It's a great mower.... but only when it has great maintenance. [This is all water under the bridge.]

• My primary question NOW is: what have you done in the hours between 1270 and 1370 ?? That's 100 hours and the machine should have experienced at least 2 oil/filter changes. Plus, with zero maintenance history, I would have started with a complete hydraulic oil change on Day 1.

The lesson here is that high grade oil is cheap compared to new engines.

Oil in an air-cooled engine is about 4 times more important than in your water-cooled car engine. Engine parts are running MUCH higher temps in an air-cooled engine, and as such engine oil proabably represents 50% of the engine cooling system. Especially if the owner has not cleared the air cooling fins of lawn clippings on an annual basis.

I am assuming it has bad valve seals or rings (I am not a small engine mechanic).
This is nothing but wishful thinking. It's far more likely that both owners have practiced "deferred maintenance" and a great engine is simply been "used up".
 
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