timg83

Hey there, I've been reading for a while but first time poster.

here is my problem.
I just finished rebuilding a 350.
I had a machinist bore/hone/align hone the block and set up all the bearing clearances.

when finished assembling the motor, i set the valve lash and it turned over fine.
When i dropped the motor in the truck and tried to start it, it turned over a few times sluggishly, and it sounded pretty harsh.

now it won't crank at all.
the starter engages it just doesn't spin.

i took the plugs out and it still wont spin.
i took the starter off and the starter spins by itself.

now i cant even get the motor to turn by hand

any help or ideas anyone can offer would be appreciated.
Thanks

FRMULA88

First: Did you crank the engine by hand as you assembled it? especially after installing key components; Crank, rods/pistons, timing chain. This is to make sure there are no issues during assembly.

Second: Did you use assembly lube as required? file fit the rings, check all clearances?


Third: Did you prime the oil pump/engine before starting it for the first time? (dist. removed & primed with drill & priming tool) with valve covers off did you make sure oil flowed thru all the pushrods to the rockers. It usually takes 5-10 minutes to prime the engine.

Sounds like you dry started it and it's locked up...

redneckjoe

try squirting some oil in the cylinders with the plugs out and see if it helps.

timg83

i did crank it by hand when i was assembling it and it turned fine,
i did use assembly lube

and i did prime the oiling system, but not for five to ten minutes, probably only for a minute or so.

if its locked up due to lack of oil, if i prime it again for the correct time do you think it will free up?

FRMULA88

If you started the engine "dry", meaning it was never primed (or not primed correctly) and you just had assembly lube, you stand a good chance of wiping the camshaft and lifters. possibly even locking the piston rings.

Someone suggested removing the spark plugs and squirting the pistons with oil. the rings are oiled by "splashing", as the counterweights spin they fling oil on the cylinders which lube the rings

I would do that then remove the valve covers and prime the engine correctly... until you see oil come up all the push rods oil holes and reach the rocker arms.

Be patient this will take some time to complete, there is no "correct amount of time" it takes as long as it needs for the oil to reach all the rocker arms.
and you want a steady stream at each one.

BUT this process makes sure the entire oiling circuit is primed, including the cam and lifters and is a safety check: Say after 15 minutes you have no oil in the valve-train, means your oil pump / oil pick-up is not right. or you forgot to install the oil galley set screws.. etc... This will save you costly damage.

FRMULA88

LOL it take a long time to prime it when it's new.
but what you want to see on all 16 rocker arms is what you see on 1, 3, & 5 exhaust rockers in this picture


My builder working the drill as we got my motor ready for the dyno.

Note: the cardboard "dam" to keep the oil from spilling over the side of the heads.

FRMULA88

This is a critical step and has to be done to ensure proper start up.

I don't know what state your engine is in right now but it it's locked up priming at this point may not help..

You can try and if it does not free up by hand cranking forwards or backwards I suppose you could force it with the the starter, but at that point you probably have metal to metal contact due to lack of oil...

if it can't crank my hand you have an issue.

bwiencek

Manual or automatic? If it's an automatic - see if you can un-bolt it and pull the converter away from the engine and then see if the engine spins free (although that's going to be tough to do when the engine won't turn) - are you sure you properly seated the converter?

Try using a flywheel turner to move it back and forth and see if it'll move manually. If you dropped something in the intake and that is jamming a piston no amount of priming will get it to turn over (but it should turn 'backwards' away from the jam), if a valve keeper came loose no amount of priming is going to get it to turn over (again it will be obvious if you pull the valvecover or rotate the engine backwards). If you siezed a bearing to the crank - well do you really want it to turn over (the damage is going to still be there)

You need to figure out what is "stuck" or "stopping" the rotation and none of that is going to be simple or solved by dropping a little oil down a cylinder of an engine that was fresh...

Also - are you sure it's "stuck" - (i.e. are you sure you've charged the battery fully and connected the grounds to the engine properly and the connections are super clean and have enough ampearage to turn the starter over, etc.) Seen more than once where a weak battery/starter would barely turn a fresh engine over - especially when the battery sits for months while the engine is off being built...

FRMULA88

Make sure the transmission is in neutral or park...

you may have the converter installed wrong, try loosing the converter from the flexplate and see if the engine will turn over by hand.

IrocRoadRacer

That's what I would say. loosen those bolts, and the motor should turn. It would be easier to turn if you also took out the spark plugs. If you can't turn the motor after doing all that, its probably a seized motor.

InfernalVortex

iTrader: (4)

Assembly lube and whatnot is there specifically to protect the parts during initial startup. The lubricant that you can get for your camshafts for break in are specifically meant for protecting the parts at startup. Priming will just blow all that gunk back into the oil pan instead of leaving it in the bearings. Have you guys ever even seen how quickly oil pressure builds up on these things? You park the engine for a few days and for all intents and purposes it's a "dry" start, but you dont see engines seizing from sitting for a week. Priming is mostly superstition at this point. Do what makes you happy..

Im not gonna suggest NOT priming, but I certainly wouldnt get hung up on that as the raeson you're having issues. I think the mains get oiled quickly enough by the pump they're not really a big deal, teh assembly lube will hold them over until that happens. The cam lobes are not really oiled under pressure either, so using a good cam lubricant during assembly is important there. The lobes themselves are splash oiled for the most part, which IS a concern with a new engine, you want it to start running and spinning very quickly to break in a flat tappet cam properly. But I dont think it will care about oil priming. Neither will that cause it to seize up immediately.

I would be more concerned about camshaft timing. Maybe you've had some valves hit pistons. If it's completely seized up and you can't turn it backwards or forwards that'd be the first thing I'd worry about. Pull the valve covers and loosen the lash on EVERY rocker arm. If any of the valves dont come up to the same height as the rest.... Well tehy're bent into the chamber somewhere. See what happens after you do that. Also, the guys above are right on about disconnecting the torque converter. Definitely worth trying. I'd also take any belts off. Just eliminate as many possible sources of resistance as possible.

FRMULA88

for your reference.


this is why initial priming of new build is critical.

priming on a new build ensures the oil galleys are clear and the oil circuits flow as supposed to. You will not wash away all the assembly lube because the engine in not rotating you are merely spinning the oil pump.

http://www.cranecams.com/uploads/breakin/548e.pdf


On a camshaft with "flat" tappets you HAVE to break-it in on initial start-up.

This process ensures the flat tappets are properly broken in with the cam lobes.

Priming and cam break-in are critical steps, they are not superstitious beliefs.. there are some well intentioned cyber mechanics that unfortunately give out advise that is not based on any actual experience.

DO this wrong and you WILL wipe the cam lobes.

FRMULA88

Figure out what is causing it to bind first, then proceed accordingly.. if the engine rotated by hand during the assembly steps (hopefully you also did this after you installed the valve-train) You should not have clearance issues.


good luck

grumpyvette

from the limited info posted, and if the engines placed in neutral and won,t turn, Id strongly suspect the valves were not correctly adjusted and hes bent one or more valves and the bent valves are preventing engine rotation,or the valves are adjusted way to tightly, Id suggest removing all the rocker arms as a first test to see if it frees up rotation of the engine,if it does do a compression test, to see if you have bent valves, if the engine won,t turn,once the rockers are removed its time to pull the heads to inspect carefully, honestly the whole test and isolate process is not that difficult so approach it logically and don,t be reluctant to tear it down as far as required to locate and correct the problem, rather than making wild guesses

Richboll

Subscribed...nothing to add, just want to see what the problem is.

InfernalVortex

iTrader: (4)

Cam break in is obviously not superstitious. That's a really big deal. I suggest everyone just go to roller cams at this point. But the fact is that priming has ZILCH to do with cam break in. As far as actual priming goes, If you've got **** clogging up your oil galleys that a hand drill can unclog, (did you not clean those before assembly?!) the oil pump will unclog it on its own, immediately. Priming is good for finding out if you have a problem... That's really about it. I know lots of people who "prime" seasonal engines by killing spark and pulling the plugs and just having the starter turn the engine over for several seconds. Works just as well. You can verify you have pressure and oil up all the bearings and friction surfaces before they have to handle compression. But for a new build that should be slathered in all kinds of assembly and break in lube before you even get it into the car... I doubt priming does anything beneficial at all. Furthermore, if what you say is true and you cant pressurize the system to the point that every area oil is supposed to go, oil will already be there (of course it will drain back out by the time you start the engine anyway, so no big loss) what's the point?

Priming is akin to checking over the firing order before you start. Doesn't hurt, but if you did everything correctly, then I dont see how it could help either. If you forgot an oil plug somewhere that will prevent it from pressurizing then a drill with a gauge on the block will tell you that... assuming the drill is powerful enough. But you'll notice that when you start up the car and it doesnt build oil pressure right away either.

There's a lot of old wisdom in priming motors, and Im not gonna tell everyone to not do it. But insinuating that his motor seized because he didnt prime it long enough is absurd. Even if it seized due to a missing oil plug somewhere, priming wouldn't have fixed that unless he had a gauge on the engine while he was doing it.

FRMULA88

I take it you did not READ the flat tappet cam installation / break in procedure?

I was not there when OP assembled his engine

I don't know what he used for assembly lube or break-in oil.

He could have too much pre-load on the push rod(s) or who knows what else.

A first time builder can make ALOT of first time mistakes, but incorrectly priming a fresh rebuild should NOT be one of them.

My builder has be doing his trade for over 30 years and every new build whether it goes on the dyno for testing, or not, get's primed.

Most of his customers have their engines dynoed, not to see some magic #s, but to make sure the engine is operating correctly, before it goes in the chassis, it's nice to do but not required.

If you are going straight into the chassis it's more critical that everything in that chassis be 100% (battery fully charged alternator good, cooling system good, etc) to avoid surprises..


I will take my mine and my builder's experience over a stranger's any day.

Richboll

To prime or not to prime is not the question, its that the engine doesn't turn. Let's wait to see what the exact cause of the OP's problem is and then we can discuss the various aspects of engine building. If he was spinning it by hand, fully assembled prior to installing it, it sounds like it could easily be anything from a bad battery to a drive line problem instead of an internal problem.

1983Zsled

The others in that have replied are probably closer than I but here is a long shot.....How much oil did you put in the engine? if you overfill the crankcase..alot....you could have a case of Hydrolock. Just something else to check before proceeding.

InfernalVortex

iTrader: (4)

It depends on when he went through the valve lash procedure. It's conceivable he checked it for smooth rotation before he ever touched the lash settings. If he overtightened the rocker arms to the point that the valves were opening too far and hitting the pistons, that wouldn't show up until AFTER he set valve lash, obviously. And if he did that last... Valve lash is one of those things that's not hard to do, but it's very easy to get wrong.

evilemokid94

iTrader: (6)

As others have said, take your belts off from then front of the motor, disconnect the torque converter, and get on tjebflexplate and try to rotate the engine backwards.to see if it helps any. Gotta say though, I'm glad I didn't have any of these issues when I rebuild my l31. I didn't prime it either and its still going strong today so I can't chime in on the priming aspect.