Engine not happy!
#2
Safety Car
https://youtu.be/CamKk8kt3N8
engine aint so happy, any clues on what my knocking noise might be, ive got some idea's, getting a 2nd opinion??
engine aint so happy, any clues on what my knocking noise might be, ive got some idea's, getting a 2nd opinion??
#4
Burning Brakes
Thread Starter
#5
Le Mans Master
Had a sound just like that and it turned out to be a bad lifter that shattered and ended up completely destroying my engine.
#6
use a stethoscope or rubber hose to try and isolate the source of the noise. I had a hard to chase knock once and the return spring on the mechanical fuel pump arm had broken causing the arm to make the noise.
#7
Safety Car
After removing the heads, I found it was detonation damage (pistons and heads) to the #2, #8, and #3,#5 cyls. #5 had part of the piston broken off. I was surprised the engine was running at all. Like I said, it sounded exactly like yours.
#8
Melting Slicks
I wouldn't run it anymore. The more you run it, the less parts you'll be able to reuse. Start tearing it down. It's not going to heal itself. As suggested, start at the top and work down until you find it.
Mike
Mike
Last edited by v2racing; 07-16-2018 at 06:22 PM.
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73racevette (07-16-2018)
#9
Burning Brakes
Thread Starter
thanks guiys, will start at top and work my way in, got a boroscope coming tomorrow , so will have a look in at the valves and pistons via sparkplug hole
#10
Race Director
Grab a piece of heater hose. Makes a good stethoscope. THEN run it along the oil pan. This is an easy car to drop the pan. It is a rod. If brave enough to mess with rod bearings, get the size off the bad ones and post it.
#11
Burning Brakes
Thread Starter
#12
Melting Slicks
I would first drain the oil and pull the pan. Look at the crank assembly and inspect what's visible there. Oil analysis is a good thing for identifying failed components, but if there's a lot of Metallica present in it, just save the money you'd spend the analysis and spend it on the rebuild/replacement.
Good luck.
Just curious: What's the engine's history?
Steve
Last edited by Cavu2u; 07-16-2018 at 06:59 PM.
#14
Burning Brakes
Thread Starter
Take Mike's advice.
I would first drain the oil and pull the pan. Look at the crank assembly and inspect what's visible there. Oil analysis is a good thing for identifying failed components, but if there's a lot of Metallica present in it, just save the money you'd spend the analysis and spend it on the rebuild/replacement.
Good luck.
Just curious: What's the engine's history?
Steve
I would first drain the oil and pull the pan. Look at the crank assembly and inspect what's visible there. Oil analysis is a good thing for identifying failed components, but if there's a lot of Metallica present in it, just save the money you'd spend the analysis and spend it on the rebuild/replacement.
Good luck.
Just curious: What's the engine's history?
Steve
#15
Burning Brakes
Thread Starter
#17
Pro
Had a very similar sound on my 406 a few years ago - a roller rocker arm trunnion clip broke and the rocker arm was loose - made an awful clacking sound.
I pulled the pan and found the clip in 3 pieces.I tore the engine down, and unfortunately found some pretty bad scratches in the cylinder walls. I considered cleaning and running it - I probably could have - but instead chose to replace the block (it was an old junkyard block anyway. It was also an excuse to upgrade).
I pulled the pan and found the clip in 3 pieces.I tore the engine down, and unfortunately found some pretty bad scratches in the cylinder walls. I considered cleaning and running it - I probably could have - but instead chose to replace the block (it was an old junkyard block anyway. It was also an excuse to upgrade).
#18
Burning Brakes
Thread Starter
Update - so i removed the shaft rocker from low compression cylinder, with the rocker on, it produces 120 psi, all others are 140+, with the rocker rermoved, ie valves fully closed when turning engine over, it only managed to produce about 70 psi and then after another few trys at turning over engine, ended up down at 10 psi, so what does that mean?? bent valve or ?? - there is alot of oily burnt crusts on the pistons, which is more than likely on the valves aswell, seen on my boroscope today
Last edited by corvettedave383; 07-19-2018 at 01:17 PM.
#19
Burning Brakes
Maybe it's just the picture, but it looks like the valve stem has started mushrooming?. Maybe the rocker was pounding on the valve due to being too loose?
Also the sweep pattern looks quite wide?
Also the sweep pattern looks quite wide?
#20
Burning Brakes
Thread Starter