broken ring rough.
05-10-2013, 10:46 PM
#1
Le Mans Master
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broken ring rough.
Now the vacuum reading, rough idle, slight overheat and the oil on the plug makes sense... The cam looks fine so I think I can take the heads off and have the valves checked out once more and remove the piston from the top to replace the bad set of rings.
#5
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The rest look good!
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Some burn marks from #5 on #4.
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#5
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[/IMG]The rest look good!
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[/IMG]Some burn marks from #5 on #4.
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05-11-2013, 01:33 AM
#2
Race Director
Those are some nice pics. Not sure what I am supposed to be seeing in pic #1, but it does remind me how close everything come during rotation.
Doug
Doug
05-11-2013, 02:34 AM
#3
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Picture #1. Look at the burnt deposits underneath the #5 which was fouled. This motor has less than 500 miles so it should be very clean underneath which is the case with all of the other pistons. I found two small non-magnetic fragments on the pan which are quite bendable (broken ring). I think this is causing the rough idle, weird vacuum readings, fouled plug and slight heating condition. I bet the inside of number 5 has lots of oil burnt inside. I guess it is easy to check just time and a new set of gaskets... I thought maybe it was timing. Now, I think the ring is not sealed or partly broken on #5 since it was the one where I have been seeing some smoke on that side including oiled spark plug plus a lot of burnt underneath the piston.
Last edited by jimh_1962; 05-11-2013 at 02:37 AM.
05-11-2013, 06:15 PM
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Plus they are not very "bendable".................
05-12-2013, 02:45 AM
#8
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Not a ring! It is the oiler spacer. The thin ones which goes top and bottom of the oiler (not sure if the term is right). Now, I am definitely getting somewhere to the cause of the missing and vacuum readings. What would cause one of those to fail?
Time to pull the intake and the heads off. I will have the valves looked at when I pull the heads. Plus, check the other pistons for any wear. I might be looking at taking each one out and inspecting the rings.
I guess I would need to inspect the cylinder walls and hone it??? Not sure with such low miles.
Time to pull the intake and the heads off. I will have the valves looked at when I pull the heads. Plus, check the other pistons for any wear. I might be looking at taking each one out and inspecting the rings.
I guess I would need to inspect the cylinder walls and hone it??? Not sure with such low miles.
05-12-2013, 01:32 PM
#9
Race Director
I think the wavy oil control rings spacer is magnetic, also. You may have pieces of piston ring land, those are non magnetic aluminum, but they would have to be pretty thin to bend.
Why not post pics of the pieces?
Doug
Why not post pics of the pieces?
Doug
05-12-2013, 03:23 PM
#10
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I had another package and compared it. Sure enough it is the same thickness and material. These are not magnetic but figured out what it is. I will take pictures of the piston once I pull it.
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05-12-2013, 07:24 PM
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05-12-2013, 08:54 PM
#16
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John, any ideas why the part failed? Lots of fun work ahead... This is the second time I am going to take the heads off to get to the part. I am going to take both heads off and have them checked. I guess I could pull each piston and check them all. I did not see any problems with the other pistons. The spark plugs looked fine in the other cylinders.
05-12-2013, 08:56 PM
#17
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Also, I thought I had wiped the cam since it was off when it was running. But that's not the case. I could see the cam from underneath and it looked good.
05-12-2013, 09:03 PM
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05-12-2013, 09:13 PM
#19
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Sealed power E-251K-30
Bore (in):4.030 in.
Bore (mm):102.362mm
File Fit:No
Top Ring Included:Yes
Top Ring Thickness:5/64 in.
Second Ring Included:Yes
Second Ring Thickness:5/64 in.
Oil Ring Included:Yes
Oil Ring Thickness:3/16 in.
Oil Ring Tension:Standard
Gapless:No
Top Ring Material:Iron
Top Ring Facing Material:Moly
Second Ring Material:Iron
Second Ring Facing Material:Cast iron
Oil Ring Material:Stainless steel
Quantity:Sold as a set.
Bore (in):4.030 in.
Bore (mm):102.362mm
File Fit:No
Top Ring Included:Yes
Top Ring Thickness:5/64 in.
Second Ring Included:Yes
Second Ring Thickness:5/64 in.
Oil Ring Included:Yes
Oil Ring Thickness:3/16 in.
Oil Ring Tension:Standard
Gapless:No
Top Ring Material:Iron
Top Ring Facing Material:Moly
Second Ring Material:Iron
Second Ring Facing Material:Cast iron
Oil Ring Material:Stainless steel
Quantity:Sold as a set.