Guys,

In the final stages of getting the car back together. Here's the specs:

Stock GM crate motor shortblock, LT4 HotCam, stock heads/intake, Crane 1.6RR's.

Ok,....the motor has been assembled for about 10 months now. Back in Febuary, while on the stand, it turned over fine without much effort while setting all the valves/rockers. Bolted the clutch assembly/bellhousing up, then it sat for about 9 months. Recently the tranny, and motor were dropped back in the car. Got ready to fire it up yesturday. Nothing. The starter engages to the flywheel, but will not turn the motor over. It moves the flywheel maybe ½ inch or so then locks. When it disengages the flywheel moves back. Cannot turn the motor over by hand at all either. Tried removing all the spark plugs that way the starter didn't have to fight the compression, but still won't turn the motor over. Since it turned over fine while setting the valves/rockers the only thing that has changed is the clutch/bellhousing/tranny being bolted up. Is there anything that could be keeping it from bumping over? Yes the clutch is pushed in when attempting to start. I'm at a loss. Any ideas? I would be almost certain there's nothing going on in the bottom end of the motor since it's brand new and turned over fine on the engine stand.

Thanks in advance for any help offered.

 

Is the clutch not engaging and seperating the engine from tranny?

 

Something is blocking or binding the crankshaft. Looks like it will have to come out and a teardown far enough to look see what the problem is.

 

The clutch pedal is firm. So I'm assuming everything is working as it should. Can't really see to see if it's actually disengaging, however, with the tranny in neutral, were able to rotate the rear wheels and see the driveshaft turning. So at least nothing in the backend of the tranny is locked up. I've racked my brain and can't come up with anything. About ready to pull the tranny out, bellhousing off, and just take a look at it all.

 

Ok so you've gotten the rears to turn, thats a good sign. Also a crappy sign since you're back to square one. Hmmmm......

Perhaps drop the pan to see if something is a muck in there. Hopefully you didn't forget to put the cap on one of the connecting rods or something like that.

 

I'm guessing it's something in the bellhousing/cluth assembly area. As I said, this motor was a brand new GM crate motor shortblock, and has done nothing but sit assembled since Febuary when we could turn it over by hand on the stand when setting the valves/rockers.

 

As stated above, the bottom end was a complete assembled stock GM LT1 shortblock. All we did was install the cam, bolt the heads, intake, rockers on. At that point we could turn the motor over by hand on the stand, set all the valves, then bolted the new clutch on, then the bell housing. It sat for about 9 months, then reinstallation into the car.

 

9 months can be plenty of time for moisture creep in?? Perhaps the flywheel is binding against the block or something silly like that?? Did you turn it over after installing the flywheel?

 

Yes, but did you inspect it? I would of gone over it with a torque wrench and a few feet of plastigauge making sure everything was what it should be.

 

No, I did not. I assumed all was well. However, I still fail to see if we were able to turn the motor over by hand, why now it acts as if it's locked down.

 

I'm with you that I don't THINK its the engine, but I'd just want to make sure.

Imagine a rod cap not being bolted in place. It may of come looser and looser while turning it over many times and eventually fallen off of the rod bolts. At that point the crank lowers and the piston isn't pulled down. Upon the next upward rotation of the crank the exposed rod bolts (or the lower part of the rod) could get into the way of the journal and prevent any further movement.

Do I think this happened? No.
Is it a possibility? Yes.
Would I check anyways if removing the tranny shows no good? Yes.

 

[QUOTE]Guys,

....the motor has been assembled for about 10 months now. Back in Febuary,...... The starter engages to the flywheel, but will not turn the motor over. It moves the flywheel maybe ½ inch or so then locks. /QUOTE]

If the crank did not move at all, I would suspect corrosion and spray some rust inhibitor throught the spark plug holes, let it sit over night and fire it up the next day.
However, since the flywheel does move, and "then locks", I think a foreign object, a small screw, etc. has fallen into your engine over the past 10 months or so. Did you poly-wrap your new engine while the car was being made ready?
This scenerio is possible, ask me how I know. LOL

 

Were you able to turn the engine over AFTER setting the lifter preload with the engine on the engine stand? After all the rockers were set could you still turn it over?

Jake

 

As you said, you might have to split the engine/tranny then turn the motor over,if it turns then you can look into your clutch& pressure plate. Is the clutch installed correctly? If the clutch disk is in backwards this could explain your "spring back" condition.

 

Its got to be something in the bell housing or clutch causing this. Even if the engine was all together and the spark plugs were in the holes. If the engine was stored inside I doubt there could be enough rust or corrosion to seize the enging up enough so that it wouldn't turn. Maybe if it sat for years but not months. I have a near new LT1 that came out of my car in 1996, I took it out of storage three months ago and it turns over just as easy as it did the day I put it in storage. I opened it up and poked a bore scope into the plug holes and there was not one sign of rust or corrosion. I did however spray a bunch of WD40 into the cylinders before sealing it up for storage. And if this is a brand new engine I would be sure that there was some kind of lube on the cylinder walls.

I doubt that there is something in the timing cover causing this because he stated that he lashed the valves so that means he had to have turned the engine over several times after the cam and the timing set was installed. I would drop the tranny and peek inside the bell housing to see if I could see anything obvious. If I couldn't then I would remove the bell housing and try to turn the engine over again. And go from there.

 

Flywheel or clutch bolts too long ?

 

I would deffinately suggest that you drop the tranny and check to see if the engine turns from there. Also, make sure the clutch was installed properly. Good luck!

 

I haven't read all the ideas, but have you thought maybe after nine months crank to bearings/cam to bearings could have binded a little just take off caps add oil stick back on (assuming it hasn't rusted) and then turn over by hand to check for smoothness? sounds like not enough oil, and steel has started to bind.

 

Really stumped here. (Yeah, alot help there, I know :rolleyes: )

My clutch safety switch is disconnected and with the car in gear I could disable the fuel system and drive it with the starter, so even if the clutch is not engaging and the tranny is in gear it should still turn over. Even by hand, I almost rolled my car off jack stands turning the motor over by hand with it in gear and the rear wheels on the ground, almost.(oops).

What I'm saying is, I can't see why anything you did would cause this.

Have you tried turning the motor reverse rotation? Another left field suggestion would be a hydro-lock situation. A damaged head gasket during assembly that dripped coolant into a cylinder over ten months.

Good luck and please let us know.

 

I agree with the posiblilty of a clutch problem. Try removing a couple of bell housing bolts and install some long studs so you can nut them. Remove the rest of the bell hsng bolts and back away the housing a liitle then try to rotate the engine, if it moves you found the problem. Hope this helps....
:cheers: