How do I remove 16V head
#61
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Originally Posted by high-brass
PS: the large reliefs in the piston heads remains a mystery. This car was #1411 built. Which is outside the first 500 receiving the previous model years pistons.
Rich
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Rich,
This is the car number. I reviewed your previous posting and you did state engine number. I will go back and take a look at that. Thanks for your follow up post.
BIG AL from Virginia
84 928S euro twin distributor monster
This is the car number. I reviewed your previous posting and you did state engine number. I will go back and take a look at that. Thanks for your follow up post.
BIG AL from Virginia
84 928S euro twin distributor monster
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Cleaning carbon
Well, this did not go as I had hoped. The way it was supposed to work is squeeze oil between the piston and the cylinder wall. Then apply combustion cleaner on the face of the piston. After some time, use scotch pad to scrub off the loosened carbon. Clean and scrape carefully with a putty knife till all carbon is off. Then turn the crank clockwise and as the piston retracts the oil will have suspended the particle on the wall of the cylinder. Then wipe clean.
Well the combustion cleaner removed some of the carbon on the cylinder wall. And the cleaner seemed to breakdown the oil so it did not suspend the particles like it should have.
Anyway, I hope the bad stuff docummented here helps as well.
Big AL from Virginia
84 928S euro twin distributor monster
Well the combustion cleaner removed some of the carbon on the cylinder wall. And the cleaner seemed to breakdown the oil so it did not suspend the particles like it should have.
Anyway, I hope the bad stuff docummented here helps as well.
Big AL from Virginia
84 928S euro twin distributor monster
#64
Drifting
As to removing the sharp burrs, what did you do?
Did you grind it down, fill it in, or both, or what? It is not clear to me.
Are you going to remove the scale from the coolant?
Did you grind it down, fill it in, or both, or what? It is not clear to me.
Are you going to remove the scale from the coolant?
#66
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Al, the engine serial number is stamped in the location highlighted, behind the passenger side of the water pump.
Looks like this
Yours should start with M28/21 if 5spd, M28/22 if auto. Hope this helps.
Rich
Looks like this
Yours should start with M28/21 if 5spd, M28/22 if auto. Hope this helps.
Rich
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Originally Posted by tv
As to removing the sharp burrs, what did you do?
Did you grind it down, fill it in, or both, or what? It is not clear to me.
Are you going to remove the scale from the coolant?
Did you grind it down, fill it in, or both, or what? It is not clear to me.
Are you going to remove the scale from the coolant?
TV,
I used a dremel drill with a 120 grit sanding drum running on #3 speed to sand it down and smooth any sharp edges. I did not fill it in. I had several excellent sources that told me it would not be a problem.
I intend to try and remove the scaling. I have started to look at some chemical flushes. Do you have any suggestions?
Big AL from Virginia
84 928S Euro twin distributor monster
#68
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well, what is the engine number? i still cant believe that the 84 euro can have the deep dish valve cuts, even in an earlier version of the same year
Rich, what have you done to yours??? head removal in the car, very impressive!
MK
Rich, what have you done to yours??? head removal in the car, very impressive!
MK
Originally Posted by high-brass
Rich,
This is the car number. I reviewed your previous posting and you did state engine number. I will go back and take a look at that. Thanks for your follow up post.
BIG AL from Virginia
84 928S euro twin distributor monster
This is the car number. I reviewed your previous posting and you did state engine number. I will go back and take a look at that. Thanks for your follow up post.
BIG AL from Virginia
84 928S euro twin distributor monster
#69
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Its all in PET and pretty simple at the end really.
First engines to get high compression pistons were 0597 for manual cars and 6114 for automatics. First manual car engine number was 0001 and first automatic engine was 5001. This means there were total of 596 + 6113 - 5000 = 1709 '84 MY ROW S made with low compression pistons. VIN 1411 is 1411 - 60 = 1351th ROW car made in '84 MY. Its well within old style piston range. Even if it were not and was infact last made '84 MY ROW its still possible it could have old style engine as engines were not put into cars in any particular order.
Its also possible manual and automatic engines were given new style pistons at different times. This would mean manual or automatic cars with smaller or higher VIN than 1709 + 60 = 1769 could have late pistons. Very large difference in cutoff point isn't likely thought and above numbers give climpse into manual vs automatic car ratio in early part of '84 MY in ROW markets. Abroximately 35% of the production was manual cars.
What is interesting is that there are totally different piston part numbers for '85-86 ROW engines compared to either versions of '84 pistons. For example, looking into standard 97.00mm tolerance group 1 part numbers:
928 103 086 10 '80-84.0
928 103 086 14 '84.5
928 103 093 12 '85-86
This leads me to believe late style '84.5 pistons were just low cut early S piston casting and '85-86 were different style pistons all together.
Other interesting thing is that there are two oversize piston sizes available for both '84 MY styles, 97.50 and 98.00mm. There is only one oversize for '85-86, 97.50mm. '84 ROW S was last engine with two oversizes. After it there was only one size with three different tolerance groups available.
First engines to get high compression pistons were 0597 for manual cars and 6114 for automatics. First manual car engine number was 0001 and first automatic engine was 5001. This means there were total of 596 + 6113 - 5000 = 1709 '84 MY ROW S made with low compression pistons. VIN 1411 is 1411 - 60 = 1351th ROW car made in '84 MY. Its well within old style piston range. Even if it were not and was infact last made '84 MY ROW its still possible it could have old style engine as engines were not put into cars in any particular order.
Its also possible manual and automatic engines were given new style pistons at different times. This would mean manual or automatic cars with smaller or higher VIN than 1709 + 60 = 1769 could have late pistons. Very large difference in cutoff point isn't likely thought and above numbers give climpse into manual vs automatic car ratio in early part of '84 MY in ROW markets. Abroximately 35% of the production was manual cars.
What is interesting is that there are totally different piston part numbers for '85-86 ROW engines compared to either versions of '84 pistons. For example, looking into standard 97.00mm tolerance group 1 part numbers:
928 103 086 10 '80-84.0
928 103 086 14 '84.5
928 103 093 12 '85-86
This leads me to believe late style '84.5 pistons were just low cut early S piston casting and '85-86 were different style pistons all together.
Other interesting thing is that there are two oversize piston sizes available for both '84 MY styles, 97.50 and 98.00mm. There is only one oversize for '85-86, 97.50mm. '84 ROW S was last engine with two oversizes. After it there was only one size with three different tolerance groups available.
Last edited by Vilhuer; 03-12-2007 at 03:57 AM.
#70
Drifting
Originally Posted by high-brass
TV,
I intend to try and remove the scaling. I have started to look at some chemical flushes. Do you have any suggestions?
Big AL from Virginia
84 928S Euro twin distributor monster
I intend to try and remove the scaling. I have started to look at some chemical flushes. Do you have any suggestions?
Big AL from Virginia
84 928S Euro twin distributor monster
I agree that some chemical stuff might be needed depending on how stuck the stuff is. Do a good internet search because it might be something like a baking soda mix or simple green. I would want to use some old farmers almanac deal before using some nasty ****.
With or without chemicals I would use plastic or wood as a chisel to score it and then try prying it off. The wood could be a ruler as it has to be thin. You don't want to scratch it or chemically mess it up.
Have you measured the depth of the piston cuts so that i can compare to my 85 spare which has its heads off now.
#71
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the cuts are either near .175" or .3". typically this is for the older '83s vs the 84-'85s. the pics shown on this thread, are the deep piston cuts.
mk
mk
Originally Posted by tv
I agree that some chemical stuff might be needed depending on how stuck the stuff is. Do a good internet search because it might be something like a baking soda mix or simple green. I would want to use some old farmers almanac deal before using some nasty ****.
With or without chemicals I would use plastic or wood as a chisel to score it and then try prying it off. The wood could be a ruler as it has to be thin. You don't want to scratch it or chemically mess it up.
Have you measured the depth of the piston cuts so that i can compare to my 85 spare which has its heads off now.
With or without chemicals I would use plastic or wood as a chisel to score it and then try prying it off. The wood could be a ruler as it has to be thin. You don't want to scratch it or chemically mess it up.
Have you measured the depth of the piston cuts so that i can compare to my 85 spare which has its heads off now.
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Originally Posted by mark kibort
well, what is the engine number? i still cant believe that the 84 euro can have the deep dish valve cuts, even in an earlier version of the same year
Rich, what have you done to yours??? head removal in the car, very impressive!
MK
Rich, what have you done to yours??? head removal in the car, very impressive!
MK
The depth of the cut out on the piston is 1cm.
Big AL from Virginia
84 928S Euro twin distributor monster
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How does one explain the Porsche claims of compression for this model year Euro shown in their own workshop manual? Do they owe me new pistons? Or should I be happy for the deep cuts? Is it now an 84 euro motor with a non-interferon design? Spelling sorry?
Big AL from Virginia
84 928S Euro twin distributor monster
Big AL from Virginia
84 928S Euro twin distributor monster