Hi all,

Working on a DT3 project. The engine was seized. I got it lose with Mystery oil and it moves freely.

The crank case was almost dry. It seems this motor had very low miles but was very dry from sitting.
I don't see much evidence that water got into it.

I am concerned about rotating the engine with no gas/oil mixture that the crank bearings are not getting lubrication. Should I pour some 2 stroke oil or mystery oil down the carb intake to get some lube to the bearings? Does crankcase oil lubes the crank bearings?
Thanks

I filled up the case with 10w40 .

Somebody else that knows more than me will probably need to chime in but, I believe the oil in the fuel lubes the big end rod bearings and the crank bearings. I think the transmission bearings, clutch assembly and output bearings are lubed with the gearcase oil but I could be wrong.

Crankcase/transmission oil (10w40 etc.) lubes the tranny. 2 stroke oil in the fuel lubes the crank/rod bearings. Squirting some 2 stroke oil into the cylinder will not hurt but the only real way to get the crank bearings oiled pre start-up is to take the cylinder off and oil the bearings through the journal galleys.

Thanks for the input. Would I put straight 2 stroke oil into the galleys or premix? How much?

It may be a few weeks before I can attempt a hot start up. I just want to get the bearing living in lube until I am ready.

Thanks again.

What was seized?

Piston was stuck I am assuming. I put some mystery oil in the spark plug hole and started to tap the the flywheel bolt and got it to move. The motor is turning easily now by hand. There is resistance (compression) with without the pipe, plug and carb installed. I feel the bearing are turning easily but feel dry and rough. I am hoping some lube will get a smoother feel.

These 2 strokes are pretty bulletproof but if the bearings are trashed (and I'm not saying they are) be careful. Crank bearing failure in a running motor can equal expensive repairs.

Not a bad idea to pull the cylinder anyway to inspect the top end, check for conrod play etc.

Acknowledged, I am will move ahead carefully. Good to understand how the motor gets lube.

Many thanks!

That's kind of what I figured. It would definitely be worthwhile to pull the top end. The "roughness" you are feeling probably has more to do with piston than bearings. Would be best to clean out the grit.

Then you can easily wash out the crankcase and add a little oil to bearings if it needs it... the confusing thing is you said crankcase was dry but if you didn't pull top end you wouldn't know... bottom end could be flooded with oil. (which will make it very hard to start.)

+1 on that Mark, every "it's been sitting a long time" 2 stroke I've acquired had some measure of oil sitting at the bottom of the crankcase.