Engine Locking Up.....Won't Start??????
 

Tried to start my car last week, it turned over for a bit then made a clunking noise and wouldn't turn over at all.
First thoughts were the starter motor jammed, so thought i'd try to bump start it, but no chance, the wheels just locked as soon as the clutch was lifted in 4th gear.
Then thought the engine must be seized, was advised to try turning it over by hand off the crank pulley, done this, it was stiff but free'd up the more it was turned over, initially making a squelching noise (fuel being forced pass the pistons i think)
When i tried to start it again, it turn over for a bit then locked up again.
Turning the engine over by hand must be forcing petrol past the pistons as there is now petrol in the oil.
If i disconnect the Crank & Cam sensor (so no fuel goes into the engine) the engine will turn over with no problems.
Cam belt looks ok.
I did manage to get it to started yesterday, by freeing it by hand, then starting with the accelerator pedal fully pressed in, when started it sounded fine, only ran for a few second due to there being quite a lot of petrol in the oil, when i switched it off and try to restart it again it just locked up.

Anybody got any thought on what could be causing it lock up??? Thinking possibly faulty Crank/Cam sensor, i've order these today but won't get them til Monday.

its fooked
petrol past the pistons?..I think you're right..I think you may be missing a large portion of a piston in there somewhere

Also had that thought, either piston or ring damage, but i drained the oil today and no sign of any metal in the oil at all.
But if it was a damaged piston or ring why does it turn over fine with no fuel going into the engine?? and how did it start and run ok yesterday?? :confused:

Probably not a good idea to try and bump start it with a fuel lock in the cylinder, IMO....
Is is possible that a failed injector is allowing fuel rail pressure to flood a cylinder?

How can i check for that??

Thinking about it, I don't think it's possible. You would think that if the crank sensor is disconnected there would still be fuel pressure in the rail but the injectors wouldn't fire....? Therefore, it would still flood. Sorry for the red herring.....

compression test will give you a better picture

as said a compression test is the next step now.

i would agree with redscoob, hydrolocking with fuel. although the amount of fuel through an injector to hydrolock on one cycle would be quite large, and i'm not sure if an injector could deliver that much fuel even if stuck open unless it is damaged....

going back to the idea that an injector had seized open, if i may, if the pump is running and pressurizing the fuel line then could the fact that the cylinder is full of fuel and the pump is not running cause the lock up??:wonder:
So that, when the fuel system is isolated, the pump isnt running, the fuel line is clear, so allowing the cranking of the engine? the squelching noise be fuel passing back into the fuel line? then the engine is able to crank because no more fuel is being forced into the cylinder.:wonder:

Just a thought, but i think you can check the injector by putting a 12v source accross its plug, it will click, if not seized. i checked mine like that and they click away quite merrily. I also have a spare good injector if required, assuming you need a classic standard.

Mike

remove plugs and turn engine over by hand, you will be able to tell if there is fuel in the bores as it will fly out of the plug holes.

Whilst plugs are out, do a compression test as stated previously

Take this guys advice! start with the basics

Thanks for the advice guys, will try that next tomorrow.

This sounds exactley like the problem i had with a 2.5 conversion i did a year ago. When fitting the larger injectors i unknowingly damaged one of the bottom o-rings. The cylinder then filled with fuel.As theres 3 bar on the line,it filled the the point of hydrolock very quickly,and jamed.
I then did the same as you,turning over by hand,forcing the fuel int the oil.(only found out when checking the oil,was really full/thin)
As long as theres pressure on the line it will just keep filling,sensors/pump connected or not.
Once the o-ring was replaced,i drained the cylinder by removing the plugs and turning it over for a while.
I was lucky not to bend anything!!

Mit

I still dont understand why the fuel gets into the oil???

:wonder: I don't fully understand it either, but i guess because it has nowhere else to go unless u take the spark plugs out.

If it was a damaged/faulty injector would it not still lock up with the crank/cam sensor unplugged???
As they are what is used by the ECU to determine the injector pulse, if the injector was stuck open would it matter if it was recieving a signal or not??? :wonder:

nipped oring, hydraulic locked.. petrol will pass rings slowly but won't compress hence the lock.. you should tow start them.. you may have bent a rod doing so

remove spark plugs and remove ht leads and spin over to find which injector is leaking..

fix oring.. start it up to find out if you have bent a rod or not.. ie. knock knock..

change oil if all okay as petrol in the oil is not good

Simon

Agreed

The petrol's much thinner than oil, so the rings will pass it under compression,straight into the oil.
Another reason i found my leak so quickly, is i had a fuel pressure guage,which showed no pressure. A good leak free system should hold 3 bar.
Just out of interest,doesn't the fuel pump work all the time,regardless of cam/crank sensors? The injectors won't be opperating with sensors off,returning the fuel to the tank? So, if this is true( :wonder: ) the u/s injector may only lock open when given a signal to open,sticking between pulses,thus filling the cylinder.Which would mean it would turn over(once the fuel's been dispersed into the oil/exhaust) with no injector signal.
I am known to talk crap:freak3: ,so please tel me if i am!!

Mit

Has started once since i tried to bump it, and sounded fine, no koncking, so hopefully ok, 2.5 will be going in soon anyway but want to find the fault first to confirm 100% if this engine is still good and don't want to transfer the fault to the new engine.

you need to remove plugs to establish which cylinder is full..

just keep leads out the way or remove them and turn it over to see which one sprays fuel out.. with injector plugs off you should get no fuel

then remove that injector and replace the bottom seal

Simon

Just found exactly the same with mine, now going to remove the plugs as JGM has suggested to find which injector in causing the problem.

Definitely a fuel injector O-ring.

Check all injectors and replace o-ring,
Oil and filter change is a must. I would do once with cheap sh*te oil. run up to temperature then drop it again and put some good stuff in.

This happened to me after a rebuild a couple of years ago. Engine is still going strong.

Found it is the injector nearest the turbo :) Which is the one the squelching noise was coming from.

O-ring is in tact but seems slightly swollen, when trying to reseat the injector it doesn't want to go back in properly.
Going to get a new o-ring and try it, if not then it looks like the injector is F**Ked :(

grease the oring ;)

Simon

Tried that :thumb: Will get a new one and go from there, it's typical i only sent my orginal injectors off to be modified 3 days ago, i could of took an o-ring off them to try. :Whatever_

It's nice to find a simple fix to something that first looks really expensive(assuming that nothings been bent!):thumb: I agree with the rubish oil first method, as it will get rid of the last dregs of bad oil(don't be tempted to use flush!!):nono:

Mit

imho.. cheap oil mixed with decent is worse than a little petrol in good oil..

do an oil change and use decent oil imho.. too much cheap oil will hang around if you change it.

any left over petrol will burn off and come out the breathers once oil is upto temp.

Simon

I should have elaborated. a Cheap API spec oil would suffice.

I use a semi synth 15/50 thats £15 for 5 litres by comma its just as good as mobile one at 3 x the price