Cranking motor without a transmission installed

fourwheelinj1

Well-Known Member
Joined
Apr 11, 2011
Location
Raleigh
Should I be able to crank my jeep with 4.2 258 with only the bellhousing installed with no transmission (T-5)? The project scrambler I just bought has a questionable motor and I want to do a compression test and get if running if it will before I waste my time installing the transmission that the previous owner removed. I pulled the plugs today on the motor to put some Marvel mystery oil in the cylinders and found that 2 of the plugs were oily. One of them was actually soaked and dripping oil which seems strange for a motor that hasn't been run in 12 years. If the rings are worn enough to allow oil to get to the plug wouldn't it allow the oil to drain back to the oil pan after 12 years?
 
In theory, yes, most any motor can be run stand-alone just sitting on a stand, just need some degree of exhaust and intake etc so the flow is right.
However may run into issues w/ the harness/ECU... I don't know anything about this motor, the ECU may want to have input from several various sensors before it will start.
 
Yup, do it all the time.... Just watch the flywheel area..

Had a test/run stand back long ago with a rad and some gages. Was used for some basic tuning and breaking in cams etc.. Also planning to fire my ecotec up same way..

I would crank that engine a few times by hand to ease it in a little. Plus it will let you feel how its turning vs just using the starter.

Make sure you have oil pressure first.. Pull dist and use a drill and flat blade screwdriver.
 
no thoughts... change them. hard to draw conclusions based on unknown history of a motor thats been sitting for 12 years....

Change the oil. Crank it by hand a bit... then crank it up...
 
Do the compression test first. It will save you a lot of machine shop and parts expense if you crank it on a broken ring, stuck valve, collapsed valve spring, etc... If you have a dead hole squirt oil in it. If it seals up it is a ring if it dosent you have valve or spring issues.

Of course if you dont really care because its suspected to be :poop: hit the switch and let it run. Be sure and support the back of the engine with a jack and block of wood on the oil pan.
 
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