Hi all, I had given to me a 2017 Toro ztr with ( I think is a Loncin engine ) 708cc 24.5 hp engine, Model # 127-9040. The guy told me it was a real smoker. it been setting in my garage about a year and half till I finally got time to check it out. When I tried to start it would turn over till hit compression then stop, put in known good battery same thing, pulled valve covers put on tdc .020 feeler gauge fell straight through lol, set valves put valve covers back on engine started right up, motor sounded good ran good but immediately started to smoke. My garage is 30x40 and in less than a minute ( no kidding ) my garage was completely full of smoke, I have never seen any engine smoke like that in my life. checked compression 95 Ibs both cylinders, looking at engine diagram I seen what is called a valve breather or reed valve (which I know nothing about really ) the cork gasket was totally saturated with oil like it might be filling the cavity up ( is this normal ). Could this valve be sucking to much oil into the cylinders ( right plug was dipping with oil. Could blown head gasket (s) make it smoke that bad. what do you think.
Please post the model and serial numbers, off the ID tag, so we can see exactly what you have.
#3
kbowley
Is the oil level correct? Did you change the oil and filter? From your description, the crankcase is building pressure and blowing out the breather tube. Remove the breather hose from the air cleaner and see if it is blowing oil from it. let us know...may be bad piston rings but usually the compression would be low.
Those model and serial numbers for a Timecutater don’t show up. Please look at the ID tag again. Toro uses a 5 digit model number, like 74755 and a 9 digit serial number like 316XXXXXX.
It should be on the left side of the engine pan below the fuel pump, or the model and serial number can be found on a sticker between the engine and the seat.
#9
kbowley
Another thought...I know, scary...it very well could be a head gasket(s) failure allowing oil from the pushrod galley into the cylinder(s).
Yes, you have a Loncin engine, probably model 2P77F. Attached is the service manual for your unit. Start with the simple things first. I’m guessing either a blown head gasket or carb problem. Start by pulling both plugs, remember which side they came from and look at the color. Also, smell the oil for gas. Let use know what you found and we’ll go from there. What did you set the valve clearance at?
Rivets it is a 2P77F, standing behind the mower the right side plug had lots of oil, checked the oil before i started it it was right on no gas smell, the left plug looked pretty good
Thanks Rivets, I will the gaskets ordered doing the right side first and will go from there,really appreciate all the help, soon as I can to it I will let you know how it went .
Remember you don't just toss on new head gaskets and cut some grass. You need to lap the head AND the area where the gasket sits on the block. Never seen a flat head pulled from an air cooler mower engine. Talking about 150 grit paper and a plate glass window. I use my side garage door window. Hold the paper at the top right corner of the glass and LET THE PAPER DO THE WORK. Sorry for the caps. Just emphasizing some tips and tricks for you. No need to press on the glass other than making contact with the paper. Rotate the head as you lap.
3 step head bolt torque is another good idea.
Lastly I spray the gaskets with Permatex Hi-Tack sealant spray.
First, NEVER use a secondary sealant on head gaskets, not designed for that purpose. A head gasket should always be installed dry. Second, before you try to smooth the surface of a head, check it first with a good straight edge. You can do more damage than good if done incorrectly. I’ve replaced hundreds of head gaskets and I doubt if I’ve had 2 dozen that needed sanding.
