I would tear it apart check everything all clearances all the bearings my small block with no plugs in it will turn with with 35-40ft/lbs

 

I must have rotated it 20+ times in the late spring...now after sitting a few mos it won't rotate? The last thing I need right now is to pull this engine apart

 

Pull the spark plugs and back off the rocker arms.You may have a valve contacting a piston top.If you have a ring gear/flywheel installed..make sure it is not contacting the engine stand.Hope this helps.

 

Well the rockers are all loose and it still won't rotate...and now that I come to think of it...i think i did all the lash settings AND THEN installed the oil pump and pan which has a windage tray/ crank scraper...
parts : MOR-20191 Oil Pan and MOR-22134 Oil Pump and Pickup Assembly
...before I pull the pan is it possible the crank is hitting???...it's a 3.75 crank in a 400 block, no stroker crank here * although I am using a 6" rod...maybe that's the problem???

 

Well the rockers are all loose and it still won't rotate...and now that I come to think of it...i think i did all the lash settings AND THEN installed the oil pump and pan which has a windage tray/ crank scraper...
parts : MOR-20191 Oil Pan and MOR-22134 Oil Pump and Pickup Assembly
...before I pull the pan is it possible the crank is hitting???...it's a 3.75 crank in a 400 block, no stroker crank here * although I am using a 6" rod...maybe that's the problem???

I dont know this for sure but i'll give it a shot. If I remember correctly the 400's used 5.56? or 5.65? rods to clear the extra stroke??? Has you block been machined to clear the rods? If you turned the motor 20 times prior to this it would have hit then and it wouldn't all of a sudden start doing it. Check to see if the flywheel or rear of the crank is hitting the engine stand... that is what happend to me.

 

Two words... UH OH !!! Start from scratch and re check everything. Always better to do it right the first time. Will save you LOTS of TIME and MONEY down the road.

 

If it turned when you put it together, it will turn now.

Pull the balancer off, and get one of those tools that engages on the crank keyway, then you don't have to worry about breaking the crank bolt. Lean on your breaker bar, sh'll move.

 

Stop leaning on that crank bolt before you go bad to worse.

You don't need to pull the balancer to use a crank tool. There is one that bolts to the balancer in place of the pulley. I bought one from Summit or Jegs last year to use when I was spinning my ZZ502 while priming the oil system.

I assume your valve covers are off or you wouldn't be able to see oil coming off the rockers while priming. If the covers were on and you are using roller rockers under covers that are too short, there's a possibility of interference there.

If the motor you are speaking of is a stroker, and the bugger turned with the pan off like you said, then you might be bumping rods into your pan or windage tray. Pull the pan and try again.

Does it turn in the reverse direction?

The only other thing I can think of (considering it used to turn and now it doesn't after sitting for so long) is that if you didn't use liberal amounts of assy lube in all the right places, perhaps the internals have corroded together enough to keep it from rotating.
Tim

 

If you have the flexplate/flywheel on it, use a long screwdriver to pry against the teeth of the ring gear at one back corner of the block or engine stand. You can get some pretty amazing leverage this way, believe it or else.

 

If you have the flexplate/flywheel on it, use a long screwdriver to pry against the teeth of the ring gear at one back corner of the block or engine stand. You can get some pretty amazing leverage this way, believe it or else.

Yes, try this ^^ also turn in both directions, take plugs out too.

 

So,,,Dave, how'd it go? Dave?

 

I'm leaving work now...maybe I'll pull the pan tonight. Thanks for all the info guys.

 

my guess would be condensation has rusted the cylinder walls.look in the spark plug holes with a flashlite and see if you see rust.if you do,pull it apart.

 

I'll put money on the "Crank Scraper" and or Oil pan interference.

 

I didn't have enough time last night except to look and see no signs of rust...I have a feeling there's something with the windage tray. The dipstick won't drop down alll the way so that must be hitting it as well. Hopefully I'll have time tonight/tomorrow night.

 

Hmm, I seem to be having similar problems with my engine but this started during my problems when trying to get the engine to start for the first time. I know I have clearance because I checked everything over and it rotated fine even after it was in the car. When it does turn with too much effort now it makes a rubber squeek sound near the rear of the engine. Has anybody ever heard of that before?

I also backed all the valves off. I m wondering if it might be the timing chain binding up.

I really don't see how his oil pan or tray could cause the problem unless it wasn't installed when it turned before. When I installed my tray (Milodon) I did have to bend it a bit to get it to clear in the front and this is with a 327.

 

well I just had some time to pull the pan...it wasn't the pan or screen...still can't turn it over by hand...don't see it hitting...I have no idea what it is...but ruled out pan, valves, valve train, cylinders don't show rust. the crank threads are a little f'cked from all the torque I leaned on it but the crank bolt doesn't spin free so I don't think it's that either. can it be something with the timing chain? thanks

 

I'd just start working backwards. Pull the oil pump and pump shaft and try to spin. Then pull the valvetrain and try to spin. If that doesn't work, pull the timing chain.

 

Dave you haven't ever told us if you have the flywheel on unless I missed it.

A too long flywheel bolt can hit the block.

Are the big ends of the con rods free(side play)?

Does the crank have end play?

On your balancer bolt threads, you can just tap em out and get a bolt that's 1/2" longer and you'll be fine there.

 

Dave you haven't ever told us if you have the flywheel on unless I missed it. A too long flywheel bolt can hit the block. Are the big ends of the con rods free(side play)? Does the crank have end play? On your balancer bolt threads, you can just tap em out and get a bolt that's 1/2" longer and you'll be fine there.

no flywheel on.

i'll check on the other questions.

(taking a break to watch the yanks blow game 2)

 

Not sure if this might be an option but if the wrong bolt is used to attach the oil pump to the rear main cap you can damage the rear main bearing/crank journal. Not sure it this would totally stop it from turning but might be worth a look since the pan is off.

 

What did you do to it AFTER it was turned over before? If it turned fully over before and won't now, it's something you did after turning over, or I'm going with the previous mention of light rust at the rings and cylinder wall, where they have been touching for the last few months, you won't necessarily see the rust. It also could be any other piece that has metal to metal contact, or all of them a little bit.
You definately need to quit using the crank bolt and get a proper piece to turn it over, then try to break it loose. If you use the proper tool, you will flip the engine off the stand before you break anything, if you have 8 rings lightly fused to the cylinders, it will take a pretty good stroke to break it free.
Also, if it was a clearance issue, it would turn backward still, unless it was real bad.

 

Has this engine got a fuel pump on it yet?

If so take it off and pull the fuel pump rod as well. The rod could be held in place by the bolt(Long one for pump install) and when the cam comes around to drive the rod the engine stops. Most likely it should rock back and forth but I haven't seen a reply as to whether the thing will budge backwards either.

 

when I try to turn couter-clockwise the crank bolt just comes off. I need a tool to turn it using the keyway on the crank. (i just re-tapped the hole after taking the balancer off.) but it hasn't budged fwd OR back

I used an arp stud to mount the oil pump. I also had to remove the rear cap a few mos ago...possible I damaged that bearing? maybe...I had an issue getting the oil pump driveshaft to drop through so I had to remove the rear main.

*WHEN I TRIED TO PRIME the engine I only got one rocker arm dripping any oil out...can this be an indication of damage to the rear main bearing???

*as far as play in the crank, by hand, I can't budge it fwd or backward in the block

the fuel pump rod is not contacting the cam right now

(yanks blew the game so I'm going to head back out and check on the rear main)

THANKS for all the help tonight!! =)

 

In lieu of further hurting the crank with the bolt, have you tried putting a couple of flywheel bolts into the rear side of the crank and then use a bar or something to turn the crank over. Make sure not to run the bolts in too far or they may hit the block and then become the problem.

 

didnt think of that, will go give it a try

 

I think now that I would spray each cylinder with WD 40 and let it set for a day. With the damper on, you can use a pipe wrench clamped down snug sideways on the flange of the damper. You side-load the pipe wrench doing this but I have used this method a lot of times. Until you find out if you can or cannot turn it backwards it is just a guessing game. If you can turn it backward then there is something out of place. If you can't turn it backward then I am going with the rust suggestion.

 

I used a breaker bar on a flywheel bolt and she doesn't wanna turn counter-clockwise either.....its time to sit down and drink another beer

 

Just wonder if you got a rod backwards(GM) the little cap flanges could hang on eachother. Other thought , rod bearing tabs in wrong place? Water in cly? but you said it would not turn backwards either.

 

alot of times when the cyl flashrusts, the motor wont spin either way, but you can,as deerhunter said, spray pb blaster or wd40 into the cyls via the plug holes...with the plugs out, rock the motor back and forth...i had a frozen 454 in a boat that i broke free by taking the crank pulley off...mark the boltholes out on a piece of 1/4 plate steel...(about the same size as the pulley)drill the holes including a large hole for the crank bolt right in the center...(unibit works good here)weld a piece of crap 1/2 drive socket onto the plate over the crank bolt hole...if you have a 7/8 or bigger, that works well,as you have plenty of material to weld to...bolt the new tool onto the crank, and use a breaker bar to rock the motor loose...the bbc i used this meathod on actually broke the crank bolt off trying to use it to do this...i was able to extract the bolt without issue, but thats not always the case, so easy on the crank bolt...there were no noticable ill effects with this meathod on the boat except for the first 10 mins smoke cloud...lmao...after that, it cleaned up and ran great...keep in mind that you could possibly crack a ring doing this, so be a little ginger...

 

I bought a 49 Chevy PU one time, for it's cab. Wanted it for our 50. The engine in the 49 was siezed terrible. I couldn't resist

I put many many flavors of oil in the cyls, and let it sit a day or 2, blow it out with air and put a different flavor. Repeat, rinse with solvent, etc. Did this over about a 2 week period. And I gradually got it broke loose. A teeny bit at a time it would turn further and further back and forth. Until finally it would go through.

Then I pulled the cab off, and forgot about it a month or 2.

And one day I was bored or got a wild hair, and decided I would make that engine run

Like I say, it would spin. But there wasn't anybody home.
That engine had 30# on 1 cylinder and 0# on 5 cylinders.

I tried more oils of various flavours to no avail, the rings never freed. And I got to thinkin. What's to be lost? Nuthin.

So I put about all the oil I could get in each cylinder. Got all my ignition and carb just perfect. Put 12 volts to the 6 volt starter. Gave her a good heavy overdose of ether.... hit the starter and oh that was a pissed off motor for 20 or 30 frightening seconds cuz I just kept laying the ether to it...and then blam, that thing was runnin. AND it ran sweet(on gasoline) no knocks or misses BUT....

God that engine smoked. We laughed until we about cried. Named it Smokey. Ok, so I set me a bucket up on the frame and hoist my carcass up there and sit at the wheel and throw her in gear and dump the clutch.... and Smokey smoked 'em. Oh man it was funny. The tires were 30+ years dry rotted and heaving chunks. You couldn't tell which end was making the most smoke. That was a good time.

 

I sprayed wd40 into the plugs holes, will borrow from a buddy this week that special wrench that grabs the end of the crank by the keyway...I'm gonna lean on it...we'll see what happens. Wish me luck/ thanks for all the advice.

 

There is a trick that is good to use with stuck hardware. I presume a flash-rusted motor would benefit from the same trick. When you get the motor to turn, don't force it to turn continuously in the same direction. Go forward a few degrees and then back a few degrees. This will help break off the rust and keep it from lodging in the rings and cylinders.

 

WILL DO...THX