Replacing Pistons Rings...
#1
Three Wheelin'
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...without removing engine. Has anyone done this and can share your thoughts/insights/recommendations.
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.
![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
#2
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...without removing engine. Has anyone done this and can share your thoughts/insights/recommendations.
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.
![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
#3
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...without removing engine. Has anyone done this and can share your thoughts/insights/recommendations.
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.
![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
#5
Burning Brakes
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...without removing engine. Has anyone done this and can share your thoughts/insights/recommendations.
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
Somewhere along the road of engine break in, something went horribly wrong. The rings have never seated, my compression numbers are below what i'd expect on a new motor (125-128) and leak down has gone from acceptable 5-7% to miserable 15-18%. It literally sounds like a jet taking off out of the oil filler tube.
![soapbox](https://rennlist.com/forums/graemlins/soapbox.gif)
This trully sucks...
#6
Three Wheelin'
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Chris - I'm not exactly sure what the cause could be. I followed a conservative break in routine. I used non-syn 20/50, changed at 250/750/1500 from there went to VR1 20/50.
What else could cause this failure?
The bores are Alusil bored to 100.5. The pistons were new Mahle, with rings.
The motor has approx. 3,500 miles on it.
Back in the beginning...
The only thing I can think of is during my initial tuning it went extremely lean for a few moments before I shut it down. When I opened the hood the headers were glowing red hot. This all happened in the matter of seconds, it went very lean. I've always wondered about this. I might have cooked the top sealing ring just enough... At this point I'm really hoping this is my worst case scenario and the cylinders have escaped damage.
Weighting my options for the moment...
What else could cause this failure?
The bores are Alusil bored to 100.5. The pistons were new Mahle, with rings.
The motor has approx. 3,500 miles on it.
Back in the beginning...
The only thing I can think of is during my initial tuning it went extremely lean for a few moments before I shut it down. When I opened the hood the headers were glowing red hot. This all happened in the matter of seconds, it went very lean. I've always wondered about this. I might have cooked the top sealing ring just enough... At this point I'm really hoping this is my worst case scenario and the cylinders have escaped damage.
Weighting my options for the moment...
#7
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Did the shop follow the correct alusil boring procedure?
Alusil usually is a lot less fussy than steel for break in.
Willard? Is that really you?....you don't usually miss stuff like that! Yes, you need to drop the oil pan and remove the pistons from the top - but dropping the crank takes a lot more - you would need to remove the entire front of the engine to get to the oil pump and remove that. You would also have to remove the bell housing to get the flywheel off....at that point you might as well just pull the engine!!
On the bright side - you can clean up the cylinders with the crank in place.
Alusil usually is a lot less fussy than steel for break in.
Willard? Is that really you?....you don't usually miss stuff like that! Yes, you need to drop the oil pan and remove the pistons from the top - but dropping the crank takes a lot more - you would need to remove the entire front of the engine to get to the oil pump and remove that. You would also have to remove the bell housing to get the flywheel off....at that point you might as well just pull the engine!!
On the bright side - you can clean up the cylinders with the crank in place.
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