Blown Piston
My #4 piston blew up yesterday It was running beautifuly then all of a sudden BAM and the engine died. What makes me wonder is I'm not sure why this happened. All that I've noticed that doesn't seem right so far is that the cam on the side that blew the piston is out of time with the crank, distributor, and other cam. I'm not sure if the cam being off caused the piston to blow or if the piston caused the cam to be out of time(which came first the chicken or the egg kind of thing). I'm still in the process of removing the afflicted piston so I can get pictures of anything in particular if it will help.
Here are some pics of the damage and the timing marks.
Here are some pics of the damage and the timing marks.
- Attachments
-
- I almost cried when I saw this
- spark_0001.jpg (46.8 KiB) Viewed 14909 times
Alex
84 GTV6
84 GTV6
My original 2.5 engine blow up in a very similar way.
I was uphill full throthle around 5800 rpm in 5th gear, and suddenly BAM, white smoke.....
I saw the spark plug like the one in the picture and then i start to look for a 3.0 engine...
No metal on the intake, but i didn´t check more things, only take the engine apart and get the rotor arm for the 3.0 conversion.
I was uphill full throthle around 5800 rpm in 5th gear, and suddenly BAM, white smoke.....
I saw the spark plug like the one in the picture and then i start to look for a 3.0 engine...
No metal on the intake, but i didn´t check more things, only take the engine apart and get the rotor arm for the 3.0 conversion.
Thanks for the replys
Heres a pic of the #4 injector and the #5(#4 is on the right )
I was running at about 4000rpm in 4th maybe 25% throttle on what I think was pretty level road. I had been driving for about an hour and half some of which was somewhat hard driving and it was pretty hot outside ( though the car was running where it should around 175 degrees)
Also I'm wondering if theres a way to get the head off without moving the brake servo. I tried to get the studs out of the end where the servo is in the way by locking 2 nuts on top of eachother and loosening the bottom one but that didn't work(I'm guessing maybe the studs are pressed in some way )
I appreciate the help
thanks
Heres a pic of the #4 injector and the #5(#4 is on the right )
I was running at about 4000rpm in 4th maybe 25% throttle on what I think was pretty level road. I had been driving for about an hour and half some of which was somewhat hard driving and it was pretty hot outside ( though the car was running where it should around 175 degrees)
Also I'm wondering if theres a way to get the head off without moving the brake servo. I tried to get the studs out of the end where the servo is in the way by locking 2 nuts on top of eachother and loosening the bottom one but that didn't work(I'm guessing maybe the studs are pressed in some way )
I appreciate the help
thanks
- Attachments
-
- injectors.jpg (50.86 KiB) Viewed 14836 times
Alex
84 GTV6
84 GTV6
-
- Verde
- Posts: 1552
- Joined: Mon Nov 29, 2004 7:06 pm
This was probably caused by either a bad injector or a bad injector seal on #4. This is quite common on 20 year old cars running original injectors and seals.
Greg Gordon www.oldebottles.com/italiancars.htm
Greg Gordon www.oldebottles.com/italiancars.htm
Hi Alex
To remove the motor, you have to remove the brake booster, which is a total pain, as you have to work underneath and inside the dash.
The cylinder head studs in the block aren't designed to be removed so leave them alone.
I don't think the small cam mistiming is what killed the motor, nor does the driving you were doing sound like the problem.
If you still want to investidate what went wrong, then try and hook up the fuel rail and look at the injector flow patterns. If #4 is much weaker than the rest, then that is the answer, not enogh fuel for #4 cylinder, lean running leading to detonation and piston failure.
Bye for now
To remove the motor, you have to remove the brake booster, which is a total pain, as you have to work underneath and inside the dash.
The cylinder head studs in the block aren't designed to be removed so leave them alone.
I don't think the small cam mistiming is what killed the motor, nor does the driving you were doing sound like the problem.
If you still want to investidate what went wrong, then try and hook up the fuel rail and look at the injector flow patterns. If #4 is much weaker than the rest, then that is the answer, not enogh fuel for #4 cylinder, lean running leading to detonation and piston failure.
Bye for now
I have heard it's possible to remove the heads by dropping the engine and tilting it forward for the head to clear the servo. To do this, you will need to drop the propshaft, engine mounts, radiator to create more room for movement.
Anyone tried this method? To me both are tough...figure out which is easier for you.
Anyone tried this method? To me both are tough...figure out which is easier for you.
Every journey is an adventure.....