Lifter/Rocker arm noise?
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From: Camino CA
Lifter/Rocker arm noise?
Whenever my car is in gear and I punch it it makes a kind of a clanking sound around 2000 - 2500 RPMs. I can rev the engine in neutral and it doesn't do this, and if I accelerate slowly it doesn't happen. I've noticed that it only seems to happen after I've been driving for about 5 minutes. I replaced the camshaft in December and I adjusted the rocker arms at that time, would I need to re-adjust them now that it's over 100 outside?
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Re: Lifter/Rocker arm noise? (Ben Taylor)
Two questions:
1)Are you sure that's not pinging you are hearing ?
2) Did you adjust the valves with the motor running ?
1)Are you sure that's not pinging you are hearing ?
2) Did you adjust the valves with the motor running ?
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Re: Lifter/Rocker arm noise? (Ben Taylor)
It only makes the noise under load?
Can you tell which side of the engine it's coming from?
Is it quiet for the first 5 minutes and then is there all the time?
If so, it sounds like piston slap to me, or maybe a loose wrist pin. Probably a wrist pin. Since Aluminum expands more than iron, the hole in the piston will grow faster than the wrist pin will. If there's any slack at all in the fit, it can make noise.
Odd though that it's only in that limited RPM range. That has me confused and thinking maybe it's something else. Is that the ONLY time you can get it to make noise? What if you rev it in Drive with the brake on (so the engine is under load)?
Dave
Can you tell which side of the engine it's coming from?
Is it quiet for the first 5 minutes and then is there all the time?
If so, it sounds like piston slap to me, or maybe a loose wrist pin. Probably a wrist pin. Since Aluminum expands more than iron, the hole in the piston will grow faster than the wrist pin will. If there's any slack at all in the fit, it can make noise.
Odd though that it's only in that limited RPM range. That has me confused and thinking maybe it's something else. Is that the ONLY time you can get it to make noise? What if you rev it in Drive with the brake on (so the engine is under load)?
Dave
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From: Camino CA
Re: Lifter/Rocker arm noise? (ddecart)
MotorHead:
1) It's not pinging, it sound kind of like a metalic rattling.
2) No, the only way I've ever done it was by turning the crank 90 degrees and adjusting each valve. I'm not sure how I could do it with the motor running without making a mess.
Dave:
The engine sounds completely normal when the car is in park or neutral.
It definitely sounds like it is coming from the passenger side.
I took it for a test drive when it got dark, and it seems to be louder as the car gets hotter.
When I did the test drive I noticed that it seems to happen exactly at 2000 RPMs and it only lasts for about a second or so. Everything seems to be fine when the RPMs are above or below 2000.
The sound is very noticable in 1st gear and there is a slight hesitation, it's about half as loud in 2nd with no hesitation and not noticable at all in 3rd.
So now I'm thinking it's something in the transmission, but the sound really seems to be coming from up front on the passenger side.
The car is an 81 with an automatic transmission.
1) It's not pinging, it sound kind of like a metalic rattling.
2) No, the only way I've ever done it was by turning the crank 90 degrees and adjusting each valve. I'm not sure how I could do it with the motor running without making a mess.
Dave:
The engine sounds completely normal when the car is in park or neutral.
It definitely sounds like it is coming from the passenger side.
I took it for a test drive when it got dark, and it seems to be louder as the car gets hotter.
When I did the test drive I noticed that it seems to happen exactly at 2000 RPMs and it only lasts for about a second or so. Everything seems to be fine when the RPMs are above or below 2000.
The sound is very noticable in 1st gear and there is a slight hesitation, it's about half as loud in 2nd with no hesitation and not noticable at all in 3rd.
So now I'm thinking it's something in the transmission, but the sound really seems to be coming from up front on the passenger side.
The car is an 81 with an automatic transmission.
