triage400

car ran perfect smooth 215 k on LS 400...This whole issue started with a bad water pump and water accumulating in valley pan around starter. So I have done a complete clean up redo Intake manifold, all new gaskets new starter, new EGR pipe, New heater valve and hoses. Front and rear Water bridges cleaned up installed w new gaskets. New Fuel injectors. New power steering pump and Hoses. Valve covers painted and new gaskets. Went ahead and replaced Timing Belt which only had 15k miles since last change. Thats where the possible problem is. With Spark plugs removed I cannot turn the crankshaft over using a 24 inch breaker bar on crank bolt. It will move back and forth from 11 o'clock to 1 o'clock position but Locks right before TDC marking on crank. Extreme pressure would be required to move it or something might break. Valve covers are off so I can visually see #1 is ALL 4 valves are CLOSED. Supposedly This first gen. 1994 ls 400 is a NON INTERFERENCE 4.0 engine. Timing marks etc on new belt are all good and lined up properly with CAM timing marks. Would the new DENSO starter cause the flywheel to lock. I havent put any battery power to starter yet. Is it safe to rotate CAMS clockwise without timing belt on to see if there is any binding on either Bank?

oldskewel

iTrader: (1)

Yes, being non-interference (90-94 only), with the TB on or off, you should be able to rotate the cams and crank however you like and there should be no valve-to-piston contact.

And that test you're suggesting is what I would do as well. Belt off. Confirm the cams turn freely. See if moving the cams has any effect on how the crank turns.

Spark plugs out removes another potential weird issue, so that's good.

You did not remove the cams or anything, right?

My guess is something external to the engine that will become clear once you do that test with the belt off. Resist the temptation to force it. It should be perfectly smooth, and if it's not, you will break whatever it is that it's stuck on by forcing it.

triage400

I Did not remove Cams. So they are good. TB is off so I did test each cam rotation clockwise and all is good. Using 3/8 socket with 15mm I turned each one 6 times back to TDC. All 4 valves closed #1. After rotating the cams I attempted to rotate crank with breaker bar.and 22mm in crank bolt. I went back in and removed the new starter just to be sure flywheel good etc. The cam rotation seemed to have allowed a little more positive movement in the crank towards TDC markings. With some amount of pressure I was able to bust thru? rotate the crank 1 revolution to only hit a hard spot again. That cant be the cam valve springs tension as the timing belt is not on and spark plugs removed. Apparently as long as piston height checked TDC with screw driver in #1 cylinder. and all 4 valves are CLOSED on # 1 cylinder. line up belt marks with cams & crank at TDC It should be good to go..??

spuds

Interesting thread.....