Nut jamming engine

[voodoo VT]

Right-o major problem.

I was just about to bolt the gearbox back to L67 to then start install tomorrow morning.

But something is stopping the engine from turning a full cycle, its doing about ¾ of one full rotation.

On sat evening I noticed the alternator power-lead nut had come off, after looking for some time I thought maybe it has dropper onto the ground and left it at that.

At this time the valve covers and charger where off.

I’m thinking the nut has fallen into the air inlet and now is on top of a piston.

Now who has a trick for getting that out?? I have thought about slinging the engine upside down and trying to get it to come out as it went in. Dose anyone know if this might work or if ill be wasting my time and should just pull the engine down to get in there.

I can’t be 100% sure this is the problem but the engine was spinning freely before I moved it into the shed to get ready for the swap over.. Any other thought on what may have happened here ??

(looks like that cam might be going in sooner then I thought)

[delcowizzid]

flex magnet down the plug hole

[ScoHar]

don't push too hard it might be stuck between a valve and valve seat = damage.

[voodoo VT]

flex magnet down the plug hole

i think the nut will be too big to get out of plug hole, for some reason they have those big head nuts on there i think 13-14mm

[Not_An_Abba_Fan]

If it won't fit through the plug hole it won't fit through the valve opening. I would say it has jammed open a valve and the valve is hitting the top of the piston. (If it has indeed dropped down inside the intake.) Take the covers off again and spin the crank backwards and see which valve stays open. Then you may be able to get down there with the chager off again.

[voodoo VT]

Right o the update.

Yeh I’m thinking maybe it has just jammed a valve open. I bought myself a flexible magnet from our good friends at super shit auto.

I’ve had it down every plug hole feeling the top of the piston doesn’t seem to pick up any loose object as I’d expect the magnet to suck the nut to it if its floating around in there. (Doubt it will come though the plug hole but at least to locate it.)

I pulled the charger off and has a quick feel around couldn’t feel anything so fair. But I think I’ll have to work out witch valve we are working with to make sure its fully open if the nut is jammed in there, so the magnet may pick it it.

Is there any changer in could work its way down the top right corner of the valve ports? There is a gap there but I’m not sure to what depth it runs.


Cheers to everyone for the replies on there, really not keen to pull that engine down to get the barsted out !!

[HARVZ-6]

still got the rocker covers off?

thats ya best bet to see if its a valve

make sure theyre all sitting right

but note that wouldnt stop the engine turning over unless the piston is hittin a valve, and that will be obvious with the covers off

hope this helps mate

[voodoo VT]

still got the rocker covers off?

thats ya best bet to see if its a valve

make sure theyre all sitting right

but note that wouldnt stop the engine turning over unless the piston is hittin a valve, and that will be obvious with the covers off

hope this helps mate

no worries man got a few things to try out tomorra now.

chees to everyone for ya help.

[Baldric]

unbolt all rockers and see if it roates then.. if it does 1 by one add a rocker back into the equasion then you will isolate it to a selected area

[voodoo VT]

Today’s effort so fair,

I took both covers off charger off loosened all rockers, engine still won’t spin full rotation. The sound when it locks up sounded deeper and I thought maybe the nut has gone though an oil channel jamming the crank somewhere

So I dropped the sump and still no sign of the barsted. But I have located it to number 3 cylinder. I thought I may be able to unbolt the con rod and drop the piston out of the bottom of the cylinder but of course there isn’t enough room.

Can I pull the valves out and get in from there or are they seated from the under side of the cylinder head?

I’ve had the magnet down every hole. Plug, injector, air intake. And I can’t seem to feel anything loose in there.

I’m guessing with the rockers loose if the nut was to be jamming a valve open this would alloy the engine to spin freely while the rocker is loose?

So with that in mind I’m guessing it must have made its way on to the piston??

Good news is the engine looks good from underside and besides a couple of small spots on the sump nice and clean in there too.

[ScoHar]

the valves are seated from the underside of the head, if you were to remove your valves it would be very easy as you would have the head off.

[voodoo VT]

the valves are seated from the underside of the head, if you were to remove your valves it would be very easy as you would have the head off.

If I pull the head off can I get the head out with out pulling the air inlet manifold out ?

I’m looking at $160 for the gasket kit to do air intake $36 for a head gasket if I can get away with doing the one side may come out alright.

[Baldric]

is this a ls1 or a v6 varient ?

[Not_An_Abba_Fan]

If the nut has jammed a valve open, even with the rockers loose, the valve would still be hitting the piston, stopping the engine from rotating. You may have to remove the head, and no, you can't do it with the inlet manifold still attached.

[voodoo VT]

I'm working with a V6 L67 motor.

so we all thinking pull the intake and head off? if im going in there should i do the other side and change that head gasket while im there ??

is it worth looking into a cam to go in now or will the fresh gaskets hold up to the engine being pulled down again? If so, where should i look for one and what would be the go for a stock L67.

[Not_An_Abba_Fan]

A cam is always a good upgrade. I would do both sides while I had it half apart anyway. It depends on your budget now, if you can afford it, do it. Get it tuned while you are at it as well.

[voodoo VT]

A cam is always a good upgrade. I would do both sides while I had it half apart anyway. It depends on your budget now, if you can afford it, do it. Get it tuned while you are at it as well.

what do you mean get it tuned man ?? as it is now or once its in and running..

i cracked the head off and it fell out as soon as the seal opened did't even get to see the bugger in there but say it was ontop of piston and just fell out.

[Not_An_Abba_Fan]

Good that you got it out.

Tuned as in retune the ECU so that it has more go.