Toro z5000 seized up?

solefate said:

I was mowing with it at the time, it lost power all the sudden and I limped it to my shop. I could smell burnt oil, and smoke was coming out of the valve cover vent line. Now, a couple days later I'm ripping it apart and I cannot turn the flywheel. I have the head off, and there is no scoring on the cylinder wall, and there was still oil in the valve cover area, and around the piston. I have no flywheel puller to make it much further. Is it a total replacement, or shall I get a puller and keep tearing it down. (contemplating this anyway for education)

Forgot to mention it was dangerously low on the dipstick, though no signs of it burning off or leaking oil before now.

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bertsmobile1 said:

Sounds like you have cooked the engine.
If you were lucky you might get out of it with nothing more than a pair of new rods.
To take the flywheel off undo the retainer then do it back up, loose 1 turn
Put a pry bar under the flywheel so it is on a strong part of the engine ( not the fins ) and also not under the magneto magnets.
I like to use the area under the magneto coils as in most cases the coils will need to be removed
Push down hard, very hard on the pry bar then smack the flywheel bolt hard with the biggest hammer you can hold.
Two people make this a lot easier.
The flywheel will pop off the taper after which it can be lifted off once the bolt is fully removed.

If you slip the belts off you can do this with the engine in the mower and in fact it is easier this way

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7394 said:

I NEVER start my mower before I check the oil level. I was raised that way.

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bertsmobile1 said:

Start by undoing the rods which may be quite awkward depending upon where it has stopped.
Push the rods up into the bore
If the flywheel is not off, take it off as you will need to remove the crank shaft.
Was not expecting you to get this far this quick so just in case you have not been doing it,,,,, TAKE LOTS OF PHOTOS
Engine with part in, then the part by itself then the engine with part removed.
If the engine is rebuildable they will come in handy,
If it is only the rods then rebuild.
If the crank has seized on the top or bottom cases then it is good night Irine.
The bottom case is replaceable for a reasonable price , but the top is a full short block which is not much less than a completer replacement engine from one of the surplus engine suppliers.
There iis no bush where the crank goes through the cases and the clearance is around 0.001" to 0.002".
I have seen some fitted with bushes but that requires a friend with a good workshop and a taste for a nice burbon :licking: otherwise the cost is way too much.

Go to Kohler.com and download your engine manual and your engine parts book.
Log on as guest when the log on screen appears.

The trick is to get the rods off and out of the way, then take the plugs out , bolt the cases together and try rocking the flywheel and the PTO shaft
If it moves left right then the engine is toast.
Up down you should have around .020" to .050" but left right is the problem.
If the crank has a build up of alloy on it where it goes through the bottom then that needs to be removed first .

When I started out I got hold of some large diameter key rings which I put a company tag on.
The mowers were always left with the keys hanging over the dip stick & i encouraged customers to do the same so it reminds them to always check the oil.
There is SFA oil in there and by the time it drops to the end of the dipstick you are doing serious engine damage.

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