Oil Leak in Spark Plug?
Thread Starter
Intermediate
Joined: Dec 2024
Posts: 25
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Wow, that does not sound like the customary LS valve train noise to me, it is much louder. I would be concerned if I were you, use your stethoscope and see if you can locate the general area where the noise if emanating from. If it is louder from the bottom of the engine, a damaged main / rod bearing, or wrist-pin bushing are strong possibilities. The engine appears to have been modified, do you have any history as to what was done?
In terms of work that's been done:
- 383 Stroker Kit
- Eagle Forged Crankshaft
- Larger Camshaft
- LS2 Ported Heads
- Sniper Induction Kit
I am not driving the car anyway or even revving it until I know what the issue is.
Le Mans Master
Joined: Jun 2016
Posts: 5,456
Likes: 4,015
From: Cincinnati, OH
Looks like you bought a car with someone's hands all over it...
Clean everything
Pull the valve covers off and check all rocker arms etc that non are loose or a bent push rod
Fix anything broken/wrong
Put in new spark plugs and wires (never a bad idea when getting a used vehicle)
Retest
Clean everything
Pull the valve covers off and check all rocker arms etc that non are loose or a bent push rod
Fix anything broken/wrong
Put in new spark plugs and wires (never a bad idea when getting a used vehicle)
Retest
Melting Slicks
Joined: Sep 2021
Posts: 2,555
Likes: 1,213
I actually bought a stethoscope and it arrived today, struggling to work out what I'm listening for. It all kinda sounded the same to me and I can't tell if the rattling I hear on the stethoscope is from the engine or just my stethoscope vibrating against the side of the engine.
Do you have good oil pressure? Seeing any metal flakes in the oil?
Le Mans Master
Joined: Jul 2010
Posts: 6,021
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Well seems like the consensus, is that its not normal so, start digging into it. Starting with the valve covers. Or just drive it. There's many post out there where people just get fursated running down nothing. If your not getting anywhere, i would take it to an mechanic before something lets go.
Thread Starter
Intermediate
Joined: Dec 2024
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Not seeing any metal flakes in the oil - my oil pressure gauge is broken sadly so I haven't been able to check.
Team Owner
Joined: May 2001
Posts: 87,404
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From: Western NY
That engine does NOT sound normal to me. Not trying to be a wise-***, but are you sure your oil pressure gauge is broken, and not showing oil pressure because there's barely any??? That engine is LOUD and not in a good way....
Thread Starter
Intermediate
Joined: Dec 2024
Posts: 25
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The oil pressure gauge is just sat at 80 PSI and literally never moves. I think the battery gauge is broken too because it is sat at 14V but I took it to a local car shop and they did a free battery check that said it's at 6% of it's life.
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Thread Starter
Intermediate
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Just an update for everyone, thank you for your help. I had a mechanic pop over and diagnose - several pistons were misfiring due to oil leaking into the cylinders which makes sense with the spark plug leak.
The rattling is from the engine being off balance and the sudden changes in torque are making the torque tensioner wobble every now and then too.
They have diagnosed it as being the valve stem seals being the cause of the oil leaking into the cylinders so these will be replaced and some new spark plugs whilst I'm at it.
The rattling is from the engine being off balance and the sudden changes in torque are making the torque tensioner wobble every now and then too.
They have diagnosed it as being the valve stem seals being the cause of the oil leaking into the cylinders so these will be replaced and some new spark plugs whilst I'm at it.
Race Director
Joined: Oct 2004
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Torque tensioner??? What is a "torque tensioner?" Do you have ported heads? Many times on ported heads, the female rocker arm hold down threads will break into the ports. Intake ports would then be creating a vacuum situation, and can draw oil into the engine that way. Might be worthwhile to unbolt the rocker hold down bolts, clean both them and the female threads in the heads with brake cleaner. Blow everything off/out with compressed air. Then use a small amount of silicone, or white teflon pipe thread sealer on each bolt thread. BE CERTAIN there is nothing on the END of the bolt, or you could hydraulically crack the rocker boss!! Torque the rockers down and see if the problem stops. Easier than removing valve springs and guide seals. If it works, great. If not, you've got 1 less area to worry about. Again, if your heads aren't ported, just go straight for the guide seals. Hope this helps someone.....
Thread Starter
Intermediate
Joined: Dec 2024
Posts: 25
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Torque tensioner??? What is a "torque tensioner?" Do you have ported heads? Many times on ported heads, the female rocker arm hold down threads will break into the ports. Intake ports would then be creating a vacuum situation, and can draw oil into the engine that way. Might be worthwhile to unbolt the rocker hold down bolts, clean both them and the female threads in the heads with brake cleaner. Blow everything off/out with compressed air. Then use a small amount of silicone, or white teflon pipe thread sealer on each bolt thread. BE CERTAIN there is nothing on the END of the bolt, or you could hydraulically crack the rocker boss!! Torque the rockers down and see if the problem stops. Easier than removing valve springs and guide seals. If it works, great. If not, you've got 1 less area to worry about. Again, if your heads aren't ported, just go straight for the guide seals. Hope this helps someone.....
I am not sure what you mean about the threads breaking into the ports?
Le Mans Master
Joined: Jul 2010
Posts: 6,021
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Weird, tenisner is in the front of engine. I would just take the belt off and see if the noise goes away.
Thread Starter
Intermediate
Joined: Dec 2024
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As I say several pistons aren't firing from too much oil entering the cylinder throwing off the balance and I am told it's 90% most likely going to be the Valve Stem Seals.
The mechanic said had it been a V4 the engine would have rattled itself to pieces but the weighty V8 semi-balanced itself out with only a slight rocking.
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Thread Starter
Intermediate
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Le Mans Master
Joined: Jul 2010
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Ok quick test. When i run into a shake like your. First thing i do is pull each injector connector and if it does change you know that's the bad one. But i think its moot now because there is another problem creating the oil. Instead of pulling all of them to find the bad ones. Or your just going to change them all??
Melting Slicks
Joined: Sep 2021
Posts: 2,555
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Look at these images of LS2 ported heads. Do you see any red ones?
Maybe it's just me but I like to be sure the replacement parts are going to fit BEFORE I start the job. It annoys me to take the thing apart only to find out I have to order new parts because what was supposed to fit, didn't.
Thread Starter
Intermediate
Joined: Dec 2024
Posts: 25
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Ok quick test. When i run into a shake like your. First thing i do is pull each injector connector and if it does change you know that's the bad one. But i think its moot now because there is another problem creating the oil. Instead of pulling all of them to find the bad ones. Or your just going to change them all??
Thread Starter
Intermediate
Joined: Dec 2024
Posts: 25
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"LS2 Ported Heads" doesn't mean much.
Look at these images of LS2 ported heads. Do you see any red ones?
Maybe it's just me but I like to be sure the replacement parts are going to fit BEFORE I start the job. It annoys me to take the thing apart only to find out I have to order new parts because what was supposed to fit, didn't.
Look at these images of LS2 ported heads. Do you see any red ones?
Maybe it's just me but I like to be sure the replacement parts are going to fit BEFORE I start the job. It annoys me to take the thing apart only to find out I have to order new parts because what was supposed to fit, didn't.
I've got the old owner to reach out to the previous owner before him and find out why it's red lol