Is my 12a dead?
05-06-08, 11:28 PM
#27
Soak that sucker Mr. Melon, at least the down time will do some good. If it's any consolation, my White One finally recovered from it's "bad apex seal" today, it has never run better!
Like Doc says, you need to know about the spark and compression. Kind of like going in for a colinoscopy, but you'll be glad you did it once you've got the data.
Like Doc says, you need to know about the spark and compression. Kind of like going in for a colinoscopy, but you'll be glad you did it once you've got the data.
05-07-08, 02:50 AM
#28
Lorem ipsum dolor sit ame
Exactly.
To the OP: what the doctor says. Get numbers on compression, esp. rear rotor. And get an actual timing light and check timing. My money would be on low compression but I've also seen out of whack timing make the car have the symptoms shown in the videos.
To the OP: what the doctor says. Get numbers on compression, esp. rear rotor. And get an actual timing light and check timing. My money would be on low compression but I've also seen out of whack timing make the car have the symptoms shown in the videos.
05-07-08, 02:25 PM
#30
Lorem ipsum dolor sit ame
05-07-08, 05:14 PM
#31
UPDATE!
Hey guys
I got my hands on a compression tester and it says it all, front rotor is all good and equal.. and the rear rotor is 1 good 2 bad... why is it always the rear rotor!
I guess I have a messed up apex seal.
I was just hoping to do everything I could to avoid accepting the fate, but now I guess its new engine time.
The car is still in running driving condition, would it damage anything if I just kept driving it? is that a bad idea?
Hey guys
I got my hands on a compression tester and it says it all, front rotor is all good and equal.. and the rear rotor is 1 good 2 bad... why is it always the rear rotor!
I guess I have a messed up apex seal.
I was just hoping to do everything I could to avoid accepting the fate, but now I guess its new engine time.
The car is still in running driving condition, would it damage anything if I just kept driving it? is that a bad idea?
05-12-08, 05:42 PM
#37
**Updated!
Today I decided to pull off the header and check the apex seals for myself.
Off with the header, i turn the engine by hand, feeling around in the rear exhaust port, (mind you, this is not a good idea, do this very slow! I nearly took the end of my finger off with a rotor ouch!)
anyways, I felt 2 good springy apex seals.. then the 3rd one.. I couldnt tell what I was feeling exactly.. either a slot where the apex seal should be.. or a very stuck rigid seal.. I cant imagine the apex seal could have shot itself out of the exhaust?! I know anything is possible.. but my car runs and drives still!
I figure I will pull the engine anyways.. and if its just stuck, I will loosen er up and away I go.. option 2 will have to be a new engine, because im sure an apex seal leaving the rotor would destroy the housing.
I tried to get my camera in there, but i only got pics of the exhaust port, and could never see the rotor itself.
my compression on the rear rotor appeared to be 60-60-30.. pretty terrible
Today I decided to pull off the header and check the apex seals for myself.
Off with the header, i turn the engine by hand, feeling around in the rear exhaust port, (mind you, this is not a good idea, do this very slow! I nearly took the end of my finger off with a rotor ouch!)
anyways, I felt 2 good springy apex seals.. then the 3rd one.. I couldnt tell what I was feeling exactly.. either a slot where the apex seal should be.. or a very stuck rigid seal.. I cant imagine the apex seal could have shot itself out of the exhaust?! I know anything is possible.. but my car runs and drives still!
I figure I will pull the engine anyways.. and if its just stuck, I will loosen er up and away I go.. option 2 will have to be a new engine, because im sure an apex seal leaving the rotor would destroy the housing.
I tried to get my camera in there, but i only got pics of the exhaust port, and could never see the rotor itself.
my compression on the rear rotor appeared to be 60-60-30.. pretty terrible
05-12-08, 06:03 PM
#39
Lives on the Forum
When I lost my apex seal, the engine seemed like it would shake itself apart at idle. And the power loss was extreme. I just barely made it home. If you are still able to drive around, I have to doubt that you really lost an apex seal...
05-12-08, 06:23 PM
#40
I actually considered driving it.. the idle sounds kinda cool.. like a bridgey
lol.. the power loss is only noticeable when starting from a stop.. when your going it accelerates nearly as well..
think it might just be stuck??
I dont know how it could suddnely *stick* itself while driving normally.. i wasnt even pushing it when it happened
lol.. the power loss is only noticeable when starting from a stop.. when your going it accelerates nearly as well..
think it might just be stuck??
I dont know how it could suddnely *stick* itself while driving normally.. i wasnt even pushing it when it happened
05-12-08, 08:13 PM
#41
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What kind of sump oil do you use: is it dino or synthetic?
What weight of oil do you use: is it 10w30 or is it heavier?
Do you add MMO or 2-cycle to your gas as a premix?
I'm just speculating, but I'm going to guess that apex seals get stuck because of high ash oil that leaves a lot of carbonish residue that bonds a seal into the mounting groove. The solution is to switch to low ash synthetic oil.
Apex seals probably break from a combination of high ash oil residue hindering their movement and excessive engine rpm that establishes destructive vibration modes that the engine was not designed for. Those destructive vibration modes can be aggravated by oil of too high viscosity that resists shearing and cavitates at high speeds.
Revving the engine high to "blow out the carbon" is a tale that goes back to my fathers teenage years. I don't believe it. Of course, I said the same thing when I was 18.
What weight of oil do you use: is it 10w30 or is it heavier?
Do you add MMO or 2-cycle to your gas as a premix?
I'm just speculating, but I'm going to guess that apex seals get stuck because of high ash oil that leaves a lot of carbonish residue that bonds a seal into the mounting groove. The solution is to switch to low ash synthetic oil.
Apex seals probably break from a combination of high ash oil residue hindering their movement and excessive engine rpm that establishes destructive vibration modes that the engine was not designed for. Those destructive vibration modes can be aggravated by oil of too high viscosity that resists shearing and cavitates at high speeds.
Revving the engine high to "blow out the carbon" is a tale that goes back to my fathers teenage years. I don't believe it. Of course, I said the same thing when I was 18.
05-12-08, 09:28 PM
#43
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I have been told this same thing by so many poorly informed people that I suspect it is apocrypha, i.e., rumor. The same kind of people repeat phrases to me that I have heard in commercials, like "the ultimate driving machine", etc.
What would be the mechanism that would remove carbon at high RPM?
What evidence is there that this actually works?
05-13-08, 12:53 AM
#45
What kind of sump oil do you use: is it dino or synthetic?
What weight of oil do you use: is it 10w30 or is it heavier?
Do you add MMO or 2-cycle to your gas as a premix?
I'm just speculating, but I'm going to guess that apex seals get stuck because of high ash oil that leaves a lot of carbonish residue that bonds a seal into the mounting groove. The solution is to switch to low ash synthetic oil.
Apex seals probably break from a combination of high ash oil residue hindering their movement and excessive engine rpm that establishes destructive vibration modes that the engine was not designed for. Those destructive vibration modes can be aggravated by oil of too high viscosity that resists shearing and cavitates at high speeds.
Revving the engine high to "blow out the carbon" is a tale that goes back to my fathers teenage years. I don't believe it. Of course, I said the same thing when I was 18.
What weight of oil do you use: is it 10w30 or is it heavier?
Do you add MMO or 2-cycle to your gas as a premix?
I'm just speculating, but I'm going to guess that apex seals get stuck because of high ash oil that leaves a lot of carbonish residue that bonds a seal into the mounting groove. The solution is to switch to low ash synthetic oil.
Apex seals probably break from a combination of high ash oil residue hindering their movement and excessive engine rpm that establishes destructive vibration modes that the engine was not designed for. Those destructive vibration modes can be aggravated by oil of too high viscosity that resists shearing and cavitates at high speeds.
Revving the engine high to "blow out the carbon" is a tale that goes back to my fathers teenage years. I don't believe it. Of course, I said the same thing when I was 18.
I add 2 cycle to my gas because I removed the OMP
Either the apex seal is gone completely, or stuck.. I did not feel any pieces or partial spring, its just a rigid edge, either the seal itself or the rotor edge, i should be able to tell.. but I cant
05-13-08, 12:58 AM
#46
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vacum leak
Check the intake for leaks, Had one that could not get to idle, adjusting the carb did nothing. Rebuilt the carb, nothing, finally checked and found that the intake gasket had blown out at the rear housing. Easy fix. If you got good compression then thats what I'd look for .
05-13-08, 09:59 AM
#47
7less for now!
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dude if you read the whole thing you would know he does not have good compression jesus noobs. soak the affected seal with sea foam. get a squirt bottle and soak that sucker!
