#1 piston cleanest
Thread Starter
Burning Brakes
Joined: Jun 2001
Posts: 924
Likes: 0
From: Columbia South Carolina
#1 piston cleanest
Hello everyone,
I finally got both heads removed from my '87 and they are in the machine shop.They were removed because of a blown head gasket. the tops of all of the pistons are covered with serious carbon buildup except for #1 which is extremely clean with virtually no carbon. In your opinions,why is #1 so clean? Thanks in advance to all who respond.
tankman
I finally got both heads removed from my '87 and they are in the machine shop.They were removed because of a blown head gasket. the tops of all of the pistons are covered with serious carbon buildup except for #1 which is extremely clean with virtually no carbon. In your opinions,why is #1 so clean? Thanks in advance to all who respond.
tankman
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Coolant leaking into the cylinder while the engine is running will clean off the top of the piston. Did your machinist show you the gaskets when you took them off and indicate which cylinder he thought was the problem. I remember that you indicated he showed you a couple of areas, is this one of them?
If you still have the gaskets, you could look at them and see if there is a break leading into cylinder #1.
If you still have the gaskets, you could look at them and see if there is a break leading into cylinder #1.
Thread Starter
Burning Brakes
Joined: Jun 2001
Posts: 924
Likes: 0
From: Columbia South Carolina
Coolant leaking into the cylinder while the engine is running will clean off the top of the piston. Did your machinist show you the gaskets when you took them off and indicate which cylinder he thought was the problem. I remember that you indicated he showed you a couple of areas, is this one of them?
If you still have the gaskets, you could look at them and see if there is a break leading into cylinder #1.
If you still have the gaskets, you could look at them and see if there is a break leading into cylinder #1.
Hello John,I still have the gaskets,I'll take them back with me when the heads are done and get an opinion from the machinist. I am no good at "reading" the head gaskets,but the machinist did show me some areas and I don't remember if # 1 was one of them.I think he showed me #7 and that cylinder was loaded with coolant. The intake manifold gasket was cracked,broken,torn,and brittle. If the cylinder wall is cracked,I've got some serious thinking to do regarding moving ahead with this.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
It is more than likely a slow leak from the head gasket that sprayed the #1 cylinder. Your head gasket, then the head would fail before the cylinder wall. Remember that the block does not sit level in the car, but is slopped to the rear and #7 and #8 are the low points. So if you were not able to drain the block the coolant would seek the lowest point when you pulled off the heads....#7 or 8 cylinders. So, it would appear that #1 was leaking for awhile since it is clean. I would guess that #7 just filled with coolant when you pulled the head. Especially if there was still carbon build up on the top of the piston.
When I blew my head gasket, it was a slow leak into #8. By the time I nursed it back from LA....it was a stead flow. #8 piston had no carbon build up. It looked new and clean.
Keep the faith......
Look at he gasket for deformed areas or actual breaks. There is usually a steel "ring" in the gasket that would go around the cylinder. See if there is part of the gasket around these areas that are broken...check from the coolant passage holes to the edge around the cylinder "ring".
John
When I blew my head gasket, it was a slow leak into #8. By the time I nursed it back from LA....it was a stead flow. #8 piston had no carbon build up. It looked new and clean.
Keep the faith......
Look at he gasket for deformed areas or actual breaks. There is usually a steel "ring" in the gasket that would go around the cylinder. See if there is part of the gasket around these areas that are broken...check from the coolant passage holes to the edge around the cylinder "ring".
John
Last edited by John A. Marker; Aug 11, 2013 at 12:11 AM.
Thread Starter
Burning Brakes
Joined: Jun 2001
Posts: 924
Likes: 0
From: Columbia South Carolina
It is more than likely a slow leak from the head gasket that sprayed the #1 cylinder. Your head gasket, then the head would fail before the cylinder wall. Remember that the block does not sit level in the car, but is slopped to the rear and #7 and #8 are the low points. So if you were not able to drain the block the coolant would seek the lowest point when you pulled off the heads....#7 or 8 cylinders. So, it would appear that #1 was leaking for awhile since it is clean. I would guess that #7 just filled with coolant when you pulled the head. Especially if there was still carbon build up on the top of the piston.
When I blew my head gasket, it was a slow leak into #8. By the time I nursed it back from LA....it was a stead flow. #8 piston had no carbon build up. It looked new and clean.
Keep the faith......
Look at he gasket for deformed areas or actual breaks. There is usually a steel "ring" in the gasket that would go around the cylinder. See if there is part of the gasket around these areas that are broken...check from the coolant passage holes to the edge around the cylinder "ring".
John
When I blew my head gasket, it was a slow leak into #8. By the time I nursed it back from LA....it was a stead flow. #8 piston had no carbon build up. It looked new and clean.
Keep the faith......
Look at he gasket for deformed areas or actual breaks. There is usually a steel "ring" in the gasket that would go around the cylinder. See if there is part of the gasket around these areas that are broken...check from the coolant passage holes to the edge around the cylinder "ring".
John
I checked around the steel ring of both gaskets and all I can locate is a very tiny raised portion of the steel ring that covers the #4 cylinder. I can't identify anything else because I'm just not learned enough. I wish I knew how to post pics. Maybe I jumped the gun on pulling the heads and something else was causing the white smoke/steam to billow out of both tailpipes.
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Thread Starter
Burning Brakes
Joined: Jun 2001
Posts: 924
Likes: 0
From: Columbia South Carolina
Thread Starter
Burning Brakes
Joined: Jun 2001
Posts: 924
Likes: 0
From: Columbia South Carolina