crank won't turn by hand

[pg_thao]

today i changed my timing belt on my 6bolt, everything was fine, started it up and it died, it sounded like it got stuck or something and now my crank won't move at all.

I did do the timing again just to make sure it didnt jump a tooth and it started again and did the same thing, started and got jam.. I don;t know what can be the problem. Any idea??

BTW, i did a leak down test on all the cylinders and its good, so no bent valves.

 

[trsaudio]

hello,

take the timind belt back off and see if the crank will turn, turn the crank threw a few cycles, check to osee if there are any sticky spots. if there is a bearing spun onthe rod or the main bearing, if not then do the same to the balance shafts. this is called process of elimination. let me nkow what happens

 

[toybreaker]

Easy now....

These motors are really touchy about being turned over without the belt on.

If you're starting at tdc #1 with the belt off, and both cam dowels straight up, you can rotate the crank backwords (counterclockwise), away from the valves, 90* without any trauma. If it turns nicely, leave it there...

With the crank 90* from tdc, turn each cam, one at a time, and check for binding. They will get stiff as the rocker goes up the lobe, and then it will spring ahead as the lobe crests, and starts down the other side. Please, Be carefull, if you use a wrench, you could whack a knuckle or two, I use a ratchet.

Also, as was previously suggested, check your balance shafts. They have been known to sieze occaisonally. The rear balance shaft drives the oil pump, and it is also known to lock up.

One of my buddies left the screwdriver in the access hole on the rear of the block, (used to check the balance shaft phase), just throwing that out there...(no offense intended )

Please, keep us posted on what you find.

 

[oldman]

let me nkow what happens

My guess is either he can't turn it very far, or bent valves if he forces the issue. I just wanted to make sure readers understand what was already said in tybreaker's post, crank is not to be turned (unless you have a good understanding of egine internals) without a timing belt while head and cams are still attached.

 

[pg_thao]

alright, i did spun the crank with the belt off and cams notches at 12, spins freely, did the 90 degree thing, seems to be ok, so i put back the belt back on and crank it. Spun freely for 3 rev and then got stuck. How can i check the balance shafts to see if they are shot?

 

[toybreaker]

Conviently enough, there's no clearance issues with the balance shafts, so you can spin them (with the belts off) without damaging anything.

I wouldn't get too crazy with the front balance shaft, as there's only residual oil coating the shaft/bearings, and after a few turns, it may start to go dry, but within reason, you can spin it without hurting anything.

In fact, putting a 14mm socket on a cordless drill and spinning the rear balance shaft/oil pump may help you to find the problem. Please, do not use an impact gun, (or even an air ratchet) to spin the rear balance shaft. The resistance from the oil pump pumping cold, thick oil will cause the higher power air tools to overtighten/break/strip the balance shaft hardware. Your drill will probably start turning pretty fast, and then bog down some when the oil pump starts moving oil around. Just keep turning it for a bit, the pitch/speed shouldn't change much, after the pump is primed and pumping oil through the system..

I'm sorry, I didn't catch if the cams turned freely from your post. With the crank midway, did you turn the cams individually? With the crank/pistons at half mast, you can turn the cams, one at a time, to check for binding/other difficulties, without running the valves into anything. Could you clarify that part for me? (thanks!)

Please, keep us posted, I'm curious as to what the problem is!

 

[anubis]

indeed a very strange problem... at first i thought this was going to be a post from a newbie engine rebuilder who put the crank girdles in the wrong spots or the connecting rods on backwards or something along those lines.

good luck with the trouble shooting and keep us informed.

 

[nightspeed87]

also your cams could be frozen with the valves open not allowing the pistons to turn.
I just ran into a cam cap problem on my 6bolt rebuild/ engine swap recently from the head shop putting the wrong cam caps. And my intake cam seized..... Im sure you can guess the rest.

 

[pg_thao]

with the crank at half way, i sping the cams freely 180 degres counter and counterclockwise.

as for the cams seizing it could be because i took the cams out and saw that the journals where painted and not mirror smooth. I have to sand it down back to orginal shine, just incase that is the problem.. anyone agree?

 

[oldman]

with the crank at half way, i sping the cams freely 180 degres counter and counterclockwise.

as for the cams seizing it could be because i took the cams out and saw that the journals where painted and not mirror smooth. I have to sand it down back to orginal shine, just incase that is the problem.. anyone agree?

That is definitely a possibility.

 

[pg_thao]

thanks for the inputs, car runs now, it was a seized oil pump ,

 

[blizz99]

I also have a problem like this, sorry to use your thread, pg thao, but I didn't want to start a repitive thread. My problem is I can spin freely up until a certain point. The spot that I can't move anymore is about the 2 to 3 o'clock position. It spins freely clockwise and counter clockwise. Anyone have any clue what this is from?

 

[TwoLiterLaser]

Is the head on the car?

 

[blizz99]

yea, and belt on

 

[blizz99]

I just found out that my friend turned it without the belt on.

 

[toybreaker]

Blizz99,

I'm not quite sure what you mean when you say the two or three o'clock position...is that on the crank or the cams?

Either way, if the marks were aligned afterwords, and the belt was reinstalled, and now the motor won't turn over by hand, you may have bent some valves.

A cylinder leak down test will tell the tale.