Noise at cold startup??
Thread Starter
Racer
Joined: Jun 2000
Posts: 428
Likes: 1
From: Friendswood Texas
Noise at cold startup??
When I start my 86, after it has been sitting over night, I can hear a rattling/tapping noise from the engine for a few seconds. It then goes away. Subsequent starts during the same day are normal without the noise.
Let it sit over night and I get the noise again on the first start.
The engine is 100% stock - well maintained - running great. No loss of power. Oil pressure is normal. It's got 147k miles on it.
Any ideas? It's almost like something is losing lubrication as the engine sits (oil drains back to the pan). Then when it starts is makes a racket until oil circulation restores the lub. Any help would be greatly appreciated.
Let it sit over night and I get the noise again on the first start.
The engine is 100% stock - well maintained - running great. No loss of power. Oil pressure is normal. It's got 147k miles on it.
Any ideas? It's almost like something is losing lubrication as the engine sits (oil drains back to the pan). Then when it starts is makes a racket until oil circulation restores the lub. Any help would be greatly appreciated.
Pro
Joined: Oct 1999
Posts: 515
Likes: 0
From: Nashua NH
Mike-
If this is a new thing, it could be that your oil has lost its viscosity. When was the last time it was changed? Does it smell like gas? At 147K, you could probably stand to roll in a new set of bearings...
If this is a new thing, it could be that your oil has lost its viscosity. When was the last time it was changed? Does it smell like gas? At 147K, you could probably stand to roll in a new set of bearings...
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It sounds typical of a weak lifter to me.
Thread Starter
Racer
Joined: Jun 2000
Posts: 428
Likes: 1
From: Friendswood Texas
Changed the oil about 2k miles ago. I did change brand of oil and oil filter. I went to Mobil 1 Extended mileage and a K&N filter. Oil pressure is 60 psi cold and never goes below 25 psi at a 650 rpm idle when hot. Oil run about 55 psi when hot and rolling above 1800 rpm.
I'm thinking lifter or bearings.
I'm thinking lifter or bearings.
Burning Brakes
Joined: Dec 2006
Posts: 936
Likes: 2
From: Tyrone PA
My '05 Dodge hemi truck does that. I was worried about it till my brother said to listen to his truck. It is a 6.0 Chevy and does it twice as loud as mine for twice as long. It raps for 5 or 6 seconds then clears up. It has 80,000mi on it. He bought it new and said it has done that since day 1.
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