a few years back I had all 32 lash adjusters replaced because of a tapping noise. Quiet until now ?? what would cause a lash adjuster to go bad? seems to be the same noise as well, is there a way to check oil pressure not sure why the noise is back.
termi guys help an 01 guy
- Thread starter cobraetti
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Are you getting the noise from a particular bank, cylinder number or both banks?
These engines do have 3 different oil pressures. Main, bank 1 and bank 2. The heads actually have "bullet" style restrictor which if a piece of debris becomes lodged will reduce oil psi to that entire cylinder head. This would only be suspect if one entire bank is noisy. The restrictors are located underneath the widest cam cap with 3 bolts vs 2 and will appear as a small tube protruding from the head with the cap removed. The oil enters the bank 1 head at the rear and the bank 2 at the front. There are oil ports for obtaining the head psi's on the same surface as the exhaust manifolds. Bank 1 in front of exhaust port #1 and bank 2 behind #8 exhaust port. These ports are at the top where the am cover gasket seals.
They are not impossible to get to but not easy. I wouldn't pursue head oil psi unless there is noise from an entire bank vs the other bank. Also if a head oil psi restrictor was clogged with debris it wouldn't take a few year for the noise to return.
Is your valvetrain stock or do you have upgrade valve springs, cams, etc?
These engines/lash adjusters are sensitive to oil and viscosity. If the oil has any issues with age/mileage I would start by changing it first.
These engines do have 3 different oil pressures. Main, bank 1 and bank 2. The heads actually have "bullet" style restrictor which if a piece of debris becomes lodged will reduce oil psi to that entire cylinder head. This would only be suspect if one entire bank is noisy. The restrictors are located underneath the widest cam cap with 3 bolts vs 2 and will appear as a small tube protruding from the head with the cap removed. The oil enters the bank 1 head at the rear and the bank 2 at the front. There are oil ports for obtaining the head psi's on the same surface as the exhaust manifolds. Bank 1 in front of exhaust port #1 and bank 2 behind #8 exhaust port. These ports are at the top where the am cover gasket seals.
They are not impossible to get to but not easy. I wouldn't pursue head oil psi unless there is noise from an entire bank vs the other bank. Also if a head oil psi restrictor was clogged with debris it wouldn't take a few year for the noise to return.
Is your valvetrain stock or do you have upgrade valve springs, cams, etc?
These engines/lash adjusters are sensitive to oil and viscosity. If the oil has any issues with age/mileage I would start by changing it first.
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what I did is change to 5-40 from 5-20..i was getting a little blow-by. so after I went to a 5-40 went on a little road trip and then noticed...changed back to 5-20 after about 300 miles with the 5-40 in it. have not driven the car much since I went back to 5-20
I does seem to come from the drivers side bank as well.
I does seem to come from the drivers side bank as well.
Stock motor?
yes sir
I have never heard of an 01 cobra having the same exhaust guide wear as the 03-04 but I guess it could be possible. I would think it would be more likely if you had power adders resulting in similar HP #s as the terminators which would equate to more heat/wear of the exhaust guides.
If you are suspecting the head tick is from the exhaust guides wearing you should get a mechanics stethoscope and listen to the 6, 7 & 8 exhaust manifold runners or intermediate pipe right before the upstream bank 2 catalyst. If the noise is the loudest in the exhaust then it could be the terminator tick.
I would think it is more likely the lash adjusters based on using thicker oil which not coincidently the noise started after the oil weight swap. How about swapping in a quart of Rislone since you said you had blow by. This may help quiet the noise if in fact related to the lash adjusters and maybe help with the blow by.
Smoke on heavy accel? How many miles on engine?
If you are suspecting the head tick is from the exhaust guides wearing you should get a mechanics stethoscope and listen to the 6, 7 & 8 exhaust manifold runners or intermediate pipe right before the upstream bank 2 catalyst. If the noise is the loudest in the exhaust then it could be the terminator tick.
I would think it is more likely the lash adjusters based on using thicker oil which not coincidently the noise started after the oil weight swap. How about swapping in a quart of Rislone since you said you had blow by. This may help quiet the noise if in fact related to the lash adjusters and maybe help with the blow by.
Smoke on heavy accel? How many miles on engine?
no smoke on accel...108K on motor
I ran a bottle of sea foam through the crankcase and went for a spin..drove it pretty hard for a bit and stopped all quiet.
not sure what's going on? are lash adjusters that sensitive?
I ran a bottle of sea foam through the crankcase and went for a spin..drove it pretty hard for a bit and stopped all quiet.
not sure what's going on? are lash adjusters that sensitive?
Seafoam the combustion chamber cleaner or some type of oil additive?
as an oil additive.. figured what the heck
I hear you.... Nothing wrong with oil additives to try before cracking into the engine.
The lash adjusters are extremely finicky when it comes to oil viscosity.
Things I've seen due to oil/lash adjusters:
Misfire codes
Rough run
Tick noises
Dislodged roller followers
I was a Senior Master Tech at a Ford Dealer back in the 90's and early 2000's so most of the Guinea pigs were taxi or police interceptor 4.6. When you changed the oil these symptoms would occur on the firsts start or come in with them from the owners putting in junk oil or just wrong weight/type.
The Seafoam may have helped restore some of the "pump up" functionality to the lash adjusters or by driving hard you just got the oil nice and hot and thin and pushed out the prior installed incorrect weight and filled with the fresh/right oil type.
god I hope so
If it was mechanical then the additive really shouldn't have resolved it.
It is safe to say it is hydraulic. If it returns then you may actually have to replace the effected component/lash adjusters but it wouldn't be something I'd worry about too much.
It is safe to say it is hydraulic. If it returns then you may actually have to replace the effected component/lash adjusters but it wouldn't be something I'd worry about too much.
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