Scag mower has engine oil leak

My Scag Turf Tiger has 1650 hours and is about 14 years old, Kohler 25 hp Command Pro engine. This spring it started leaking a few drops of oil, even when parked and engine cold. Since then, the oil leak has steadily increased with use to the point oil is almost pooling on the floor. Can someone give me advice on using an additive to help stop or minimize the leak. Will this help? Does it damage the engine? Also, should I consider replacing the engine, and if so, what make and horsepower would be suggested? Thank you for your help and advice!

Mowergal said:

My Scag Turf Tiger has 1650 hours and is about 14 years old, Kohler 25 hp Command Pro engine. This spring it started leaking a few drops of oil, even when parked and engine cold. Since then, the oil leak has steadily increased with use to the point oil is almost pooling on the floor. Can someone give me advice on using an additive to help stop or minimize the leak. Will this help? Does it damage the engine? Also, should I consider replacing the engine, and if so, what make and horsepower would be suggested? Thank you for your help and advice!

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Additives are there to get you home and avoid being towed. Most will make things substantially worse and add $$$$$ to the repair so forget them.

Start by degreasing the mower thoroughly so you can see exactly where the oil is coming from
There are 3 places the engine usually leaks down the bottom
1) the dip stick tube.
It has a rubber seal or O ring depending upon the model which can go bad & leak.
This will always happen if the oil level is too high.
The level should be just below the top of the hole in the casting that the dip stick tube sits in.
I have found a lot of engines with the wrong dip stick fitted so the oil level is too high.

2) the sump gasket.
You can see the join line in the engine so look for oil leaking out of there.
Only solution for that is to pull the engine & replace it.

Both of these will leave oil on top of the mower floor and while it can & will drip down & accumulate under the mower, there still will be oil on the top.

3) the output ( PTO ) shaft or crank shaft extension if you like.
This will leak oil under & only under the floor and usually it will pool on the drive pulley then get flung all over the UNDERSIDE when the engine is running.
These can be replaced with the engine in the mower, but it is a lot easier to take it out.

Once you have determined where the oil is leaking from then you can decide what to do about it.
Blown seals oft go hand in glove with a worn lower bush which ends up requiring a new sump & sump gasket

Thank you so much! Very good advice and excellent information! I sent it to a dealership for repair. The estimate was $1200, but I was not told what/where it was leaking, and they did not de-grease the machine... I was told it would be 10 hours to pull the engine, repair it, and re-install it. I thought that appeared to be excessive and lacking specific information, I had it returned to me. It leaked very little when placed back in the barn, but after using it for 1+ hour several days ago, it started leaking and after several days of non-use there is oil on the floor over a fairly wide area, mainly towards the rear of the machine. I expected this, of course, just trying to figure out what to do next. Again, thank you for time and advice!

Mowergal said:

My Scag Turf Tiger has 1650 hours and is about 14 years old, Kohler 25 hp Command Pro engine. This spring it started leaking a few drops of oil, even when parked and engine cold. Since then, the oil leak has steadily increased with use to the point oil is almost pooling on the floor. Can someone give me advice on using an additive to help stop or minimize the leak. Will this help? Does it damage the engine? Also, should I consider replacing the engine, and if so, what make and horsepower would be suggested? Thank you for your help and advice!

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With that many hours I would think about replacing that engine, as long as the rest of the mower is in good shape

Yes that sounds like a "we really do not want to do it but if you pay us enough we will " type of quote.
Basically it is 2 hours to pull the engine and naturally 2 hours to put it back, I will be very generous and go 1/2 for cleaning.
To the 4.5 hours add 1 hour for replacing the seal or 1.5 hours for replacing the gasket.
So that is 6 hours tops, and I am a slow mechanic.

However that is putting the cart before the horse.
Your next step is to let loose with a can or 2 of degreaser and a good strong hosing down then allow it to dry .
After that run the engine for a while , say 15 minutes or so then check for oil leaks.
make sure the mower is level and the oil is not over full.
It can be a little lower that the top mark, but not below the bottom.

As an aside, I just returned an old Toro HXE tractor which was filthy with oil.
Suspecting the dip stick grommet, I removed the dip stick tube to be confronted with oil pouring out every where.
This mower had the wrong dip stick which had the oil level about 1/4" too high so it leaked out of the dip stick tube grommet.

Look for oil in the places that were previously mentioned and also check if it is more towards the front ( nearest the driver ) or back, nearest the exhaust.
Some times a breather or blown rocker gasket whill deposit oil all over the mower but be barely visible on the engine itself.

For 10 hours labor they should be about able to pull the engine, totally strip it down, bore the cylinders for a full overhaul, and reassembly and put the engine back on. Flat rate labor for R and R engine and replace the gasket/seat would be 3 hours so 4-4.5 hours would be more realistic unless the engine is a horizontal with a lot of stuff that has to be removed from the mower to get the engine out.

Hi Troops,
Scag Turf Tigers have horizontal shaft engines with crankshaft facing forward. Having repowered several TTs, they are more involved than usual and with any engine removal other areas will need attention.
I suggest repowering this tractor rather than repairing the original Kohler. However the cost to have a shop repower this machine may be high to the point of considering a new machine.:biggrin:

Mad Mackie said:

Hi Troops,
Scag Turf Tigers have horizontal shaft engines with crankshaft facing forward. Having repowered several TTs, they are more involved than usual and with any engine removal other areas will need attention.
I suggest repowering this tractor rather than repairing the original Kohler. However the cost to have a shop repower this machine may be high to the point of considering a new machine.:biggrin:

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Surely you are not suggesting that a mower vendor is handing out inflated quotes as an aid in the sales of new mowers !!!!!! scandalous, perish the thought :laughing:

Mad Mackie said:

Hi Troops,
Scag Turf Tigers have horizontal shaft engines with crankshaft facing forward. Having repowered several TTs, they are more involved than usual and with any engine removal other areas will need attention.
I suggest repowering this tractor rather than repairing the original Kohler. However the cost to have a shop repower this machine may be high to the point of considering a new machine.:biggrin:

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I have replaced a few Triads in Walkers and heaven knows how many Kohlers in Troy Bilts so am no virgin when it comes to horizontal engines.
But 10 hours is near twice the time required to do the job particularly in a properly equited workshop that regularly services that brand.

Hi Bert and group,
Lets look at this from a practical view:
Dealer cost of repower engines.
Time and equipment involved just to clean the machine before engine removal.
Time involved to prepare the machine for engine removal and removing the engine.
Time for engine cleaning, teardown, inspection and repair cost estimate or repair.
Time to inspect other areas on the machine that need to be addressed as this machine has 1,650 hours on it.
Fuel hoses, hydraulic hoses, V belts, pulleys, spindles, tensioners, and in the case of a Turf Tiger, the drive shaft for the deck, this list goes on as you know.
And then actually doing the work!
The job isn't "done" until all the paperwork is completed, the shop area is clean and ready for the next job, the junk parts, waste oil and trash have been disposed of, the job is paid for and the machine is delivered back to the customer in full functioning order, this list goes on!
Having worked in several shops over the years, this sort of work in season takes a lot of time when quick turnaround of service is important. Encouraging the customer to consider a new machine benefits both the customer and the shop as this sort of work is off season when quick turnaround isn't as demanding.
Just my thoughts! :dance1: