Slight Cylinder Score
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From: saratoga, ca
the razor can do damage, even though the block is high silicon 15% aluminum. so be careful
I did a 2 vavlve with cam tower gasket that was just baked on from 20 years of use! it took 8hous of scraping in the car, to clean it with razor blades. nightmare! but it works. (all to do that cam swap on my part euro 2 valve)
Mark
I did a 2 vavlve with cam tower gasket that was just baked on from 20 years of use! it took 8hous of scraping in the car, to clean it with razor blades. nightmare! but it works. (all to do that cam swap on my part euro 2 valve)
Mark
Just to add to this.
The razor will not damage the surface of the block due to the high silicone content.
However I did have a cam tower gasket on a car that I just did that took HOURS to get off as it had to be scraped off in layers. It was like someone used superglue that permeated the gasket too..... bloody PITA!
The razor will not damage the surface of the block due to the high silicone content.
However I did have a cam tower gasket on a car that I just did that took HOURS to get off as it had to be scraped off in layers. It was like someone used superglue that permeated the gasket too..... bloody PITA!
Three Wheelin'
Joined: Sep 2003
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From: SF Bay Area
Mark,
Not to hijack the thread - but what do you know about cam differences on 16 valve engines - US models
What were the changes from 4.5 CIS to the 4.5 Electonic injection and to the 4.7 US motors. Is there anything gained in power by swtiching around cams. I have heard an 85-86 thirty two valve cams on an S4 will increase the horse power making the engine more like a GT. Is there an advantage to put a 4.7 cam on a CIS 4.5 engine.
I figured if anyone knows it would be you
Not to hijack the thread - but what do you know about cam differences on 16 valve engines - US models
What were the changes from 4.5 CIS to the 4.5 Electonic injection and to the 4.7 US motors. Is there anything gained in power by swtiching around cams. I have heard an 85-86 thirty two valve cams on an S4 will increase the horse power making the engine more like a GT. Is there an advantage to put a 4.7 cam on a CIS 4.5 engine.
I figured if anyone knows it would be you
Three Wheelin'
Joined: Sep 2003
Posts: 1,526
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From: SF Bay Area
Aryan,
I was joking. In my opinion the piston is toast. Keeping it would be foolish as it could further disingrate and cause much more damage to an engine block that is now salvagable.
The piston can be changed in the car. The pan probably leaks any way. Yes it is easier to pull it but some people do not have a fully equipped shop. And of course as Mark noted all the pistons should be inspected.
Sometimes the simple fact these cars are old is overlooked in the ongoing quest for perfection. But then if you want a perfect car buy a 911.
Good enough is often the best course. With a new piston all other things being equal this engine could run a very long time. Or until the transmission fails.
Harbor Frieght sells a bore scope for less than the gaskets to pull the other head.
I was joking. In my opinion the piston is toast. Keeping it would be foolish as it could further disingrate and cause much more damage to an engine block that is now salvagable.
The piston can be changed in the car. The pan probably leaks any way. Yes it is easier to pull it but some people do not have a fully equipped shop. And of course as Mark noted all the pistons should be inspected.
Sometimes the simple fact these cars are old is overlooked in the ongoing quest for perfection. But then if you want a perfect car buy a 911.
Good enough is often the best course. With a new piston all other things being equal this engine could run a very long time. Or until the transmission fails.
Harbor Frieght sells a bore scope for less than the gaskets to pull the other head.
Team Owner
Joined: May 2004
Posts: 31,296
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From: Philly PA
Mark FWIW the razor if its used the way i describe will not damage any surface its used on.
That is to hold the razor at a 90 degree angle from the surface its being used on or perpendicular to the surface.
A fresh razor will level the surface its being used on.
You would use a back and forth motion, this is the best way to clean small deposits off of a surface without damage
Also advising to use the damaged piston isnt a good idea either,
since it has damage then it should be replaced, and since the engine is apart now is the time to do it,
if the block isnt cracked then this cylinder can live a long life, just the way it is.
Just dont use any type of abrasive cleaners on it, and put the scotch pads away
That is to hold the razor at a 90 degree angle from the surface its being used on or perpendicular to the surface.
A fresh razor will level the surface its being used on.
You would use a back and forth motion, this is the best way to clean small deposits off of a surface without damage
Also advising to use the damaged piston isnt a good idea either,
since it has damage then it should be replaced, and since the engine is apart now is the time to do it,
if the block isnt cracked then this cylinder can live a long life, just the way it is.
Just dont use any type of abrasive cleaners on it, and put the scotch pads away
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From: Ball Ground, GA
One possible cause for the carbon deposits on that piston - the top ring land could be beat down onto the ring. The stuck ring can cause blowby, which sticks the oil control rings.
Thread Starter
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Joined: Nov 2009
Posts: 8,660
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From: Dubuque, IA
Car has:
New trans
New steering rack
new volvo motor mounts
new alternator
new ac compressor
all new ac orings, drier, expansion valves, etc
new radiator
new oil cooler
new water pump
new timing belt
newer cam sprokets
steel oil pump sprocket
new caps and rotors and wires
new HVAC pods
porkensioner
new master cylinder
full intake refresh with every hose, gasket, sensor and vac line
all new hoses on ac, heater, radiator
rebuilt half shafts
new springs
new shocks
new oil pan gasket
new custom radiator overflow tank made of aluminum
I am pulling motor saturday. have new tolerance group 1 piston coming, new rings, new conn rod bearings, silicone oil pan gasket
pretty much got it covered.
New trans
New steering rack
new volvo motor mounts
new alternator
new ac compressor
all new ac orings, drier, expansion valves, etc
new radiator
new oil cooler
new water pump
new timing belt
newer cam sprokets
steel oil pump sprocket
new caps and rotors and wires
new HVAC pods
porkensioner
new master cylinder
full intake refresh with every hose, gasket, sensor and vac line
all new hoses on ac, heater, radiator
rebuilt half shafts
new springs
new shocks
new oil pan gasket
new custom radiator overflow tank made of aluminum
I am pulling motor saturday. have new tolerance group 1 piston coming, new rings, new conn rod bearings, silicone oil pan gasket
pretty much got it covered.
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Mark,
Not to hijack the thread - but what do you know about cam differences on 16 valve engines - US models
What were the changes from 4.5 CIS to the 4.5 Electonic injection and to the 4.7 US motors. Is there anything gained in power by swtiching around cams. I have heard an 85-86 thirty two valve cams on an S4 will increase the horse power making the engine more like a GT. Is there an advantage to put a 4.7 cam on a CIS 4.5 engine.
I figured if anyone knows it would be you
Not to hijack the thread - but what do you know about cam differences on 16 valve engines - US models
What were the changes from 4.5 CIS to the 4.5 Electonic injection and to the 4.7 US motors. Is there anything gained in power by swtiching around cams. I have heard an 85-86 thirty two valve cams on an S4 will increase the horse power making the engine more like a GT. Is there an advantage to put a 4.7 cam on a CIS 4.5 engine.
I figured if anyone knows it would be you
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Joined: Feb 2003
Posts: 29,828
Likes: 218
From: saratoga, ca
Mark,
Not to hijack the thread - but what do you know about cam differences on 16 valve engines - US models
What were the changes from 4.5 CIS to the 4.5 Electonic injection and to the 4.7 US motors. Is there anything gained in power by swtiching around cams. I have heard an 85-86 thirty two valve cams on an S4 will increase the horse power making the engine more like a GT. Is there an advantage to put a 4.7 cam on a CIS 4.5 engine.
I figured if anyone knows it would be you
Not to hijack the thread - but what do you know about cam differences on 16 valve engines - US models
What were the changes from 4.5 CIS to the 4.5 Electonic injection and to the 4.7 US motors. Is there anything gained in power by swtiching around cams. I have heard an 85-86 thirty two valve cams on an S4 will increase the horse power making the engine more like a GT. Is there an advantage to put a 4.7 cam on a CIS 4.5 engine.
I figured if anyone knows it would be you
Yes, the 85 4 valve cams are basicallly GT cams, so you get the performance of the GT by installing them, sans the ECU changes that up the rev limits and some timing /mixture differences. the 85cams need to be modified slightly on one cam (not major, but not minor either as you have to change a bearing surface) and the other cams just need the ends cut off.
Mark FWIW the razor if its used the way i describe will not damage any surface its used on.
That is to hold the razor at a 90 degree angle from the surface its being used on or perpendicular to the surface.
A fresh razor will level the surface its being used on.
You would use a back and forth motion, this is the best way to clean small deposits off of a surface without damage
Also advising to use the damaged piston isnt a good idea either,
since it has damage then it should be replaced, and since the engine is apart now is the time to do it,
if the block isnt cracked then this cylinder can live a long life, just the way it is.
Just dont use any type of abrasive cleaners on it, and put the scotch pads away
That is to hold the razor at a 90 degree angle from the surface its being used on or perpendicular to the surface.
A fresh razor will level the surface its being used on.
You would use a back and forth motion, this is the best way to clean small deposits off of a surface without damage
Also advising to use the damaged piston isnt a good idea either,
since it has damage then it should be replaced, and since the engine is apart now is the time to do it,
if the block isnt cracked then this cylinder can live a long life, just the way it is.
Just dont use any type of abrasive cleaners on it, and put the scotch pads away
I dont recomend using a damaged piston. if it is suspect, certainly remove it.
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From: Muriland
Jeff, I may be in for this on one cylinder myself. If you have the time to photograph / post the steps you follow in the piston swap, that would be hugely helpful.
Thread Starter
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From: Dubuque, IA
Heads are out at a shop being cleaned rather than me doing it with a razor blade. They'll check for square also. If they take any material off to level, I'll have to get the resurfaced head gaskets but that's no big deal.
They are also checking valve's, guides and the other stuff I know nothing about and fixing what needs fixing.
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From: Germany
Aryan,
I was joking. In my opinion the piston is toast. Keeping it would be foolish as it could further disingrate and cause much more damage to an engine block that is now salvagable.
The piston can be changed in the car. The pan probably leaks any way. Yes it is easier to pull it but some people do not have a fully equipped shop. And of course as Mark noted all the pistons should be inspected.
Sometimes the simple fact these cars are old is overlooked in the ongoing quest for perfection. But then if you want a perfect car buy a 911.
Good enough is often the best course. With a new piston all other things being equal this engine could run a very long time. Or until the transmission fails.
Harbor Frieght sells a bore scope for less than the gaskets to pull the other head.
I was joking. In my opinion the piston is toast. Keeping it would be foolish as it could further disingrate and cause much more damage to an engine block that is now salvagable.
The piston can be changed in the car. The pan probably leaks any way. Yes it is easier to pull it but some people do not have a fully equipped shop. And of course as Mark noted all the pistons should be inspected.
Sometimes the simple fact these cars are old is overlooked in the ongoing quest for perfection. But then if you want a perfect car buy a 911.
Good enough is often the best course. With a new piston all other things being equal this engine could run a very long time. Or until the transmission fails.
Harbor Frieght sells a bore scope for less than the gaskets to pull the other head.
I was just trying to figure out how some slight dings would cause a major disaster. Pistons are under stress, but I have no idea how this damage will work on the piston.
Three Wheelin'
Joined: Sep 2003
Posts: 1,526
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From: SF Bay Area
From what I saw of the picture the top of the piston was danaged. I am not sure how that happened. Maybe something fell into the engine and chewed the thing up. I once had a brass piece off a carborator fall into the engine one time. It rattled around for a while and then blew out the exhaust.
I do know of the piston is damaged enough that it will blow by gases and can burn up. This piston may have been run lean - which would suggest problems with the injection. Or there may be some problem in cooling this piston. All things to check. If more gases blow by and the piston gets fried then the piston wall will also be danaged. At that point chips can come off the piston and act as I suggested like a garnade cracking the cylinder wall.
I do know of the piston is damaged enough that it will blow by gases and can burn up. This piston may have been run lean - which would suggest problems with the injection. Or there may be some problem in cooling this piston. All things to check. If more gases blow by and the piston gets fried then the piston wall will also be danaged. At that point chips can come off the piston and act as I suggested like a garnade cracking the cylinder wall.
