I think I found my problem????????

buzzinhalfdozen · 09-26-2011, 08:40 AM

Art, I'm so glad you found this, been gone to the Sportsnats with my kid so been out of touch. As agrivating as this was for you it did at least allow you to look deeper into the operation of your system. Knowledge is power and the more we understand the easier problem solving becomes. Nice job. Joe

art leong · 09-26-2011, 11:21 AM

Quote:

Originally Posted by buzzinhalfdozen

Art, I'm so glad you found this, been gone to the Sportsnats with my kid so been out of touch. As agrivating as this was for you it did at least allow you to look deeper into the operation of your system. Knowledge is power and the more we understand the easier problem solving becomes. Nice job. Joe

Thanks Joe. But no cigar for me this time. I put it back together and while it "seemed" to run better. I still have the same problem it didn't go away. I almost can't believe that moving an exhaust cam a tooth (decreasing lobe seperation by 9 degrees). Would not show any difference. The cams look allright (not wiped) I'm wondering if my lifters (hydraulic) could be damaged. But they don't make any noises you would connect to a collapsed lifter. I did change from Schieffer 20w50 to Mobil 1 0w30 (both synthetic) Back when I started having troubles. I'm running out of things to look at.
Is it possible that the lifters are collapsing, and not making noises.
I'm thinking change the lifters, then maybe change the cams (I have some smaller cams)
And check the cams on the bench. The exhaust cam thats in the motor now is a welded regrind, but it doesn't look bad.

This whole experience is making me think of the commercial for the Holiday Inn Express. "No But I Stayed At A Holiday Inn Express Last Night"

buzzinhalfdozen · 09-26-2011, 11:49 AM

Art, that's not good news. One way I have found intermitent valve issues ie. valve sticking in guide weak spring ect. is by doing a running compression test. This requires removing the schrader from you tester so it doesn't hold pressure, running the engine you will see the needle fluctuate wildly however if you look at it closely you will see where it hits its high number. watching for the needle to not go to that high number at times is an indicater that something in the valve system is amiss. I would think this test would pick up a lifter thats bleeding down as well. As far as it making a noise I'm unsure of the answer to that as the cam is always in contact with the lifter and it bleeding off and not moving the follower, I would think would result in no detectable noise, it simply would not move the valve.On stock engine these problems are easier to find with a simply vacuum gauge as they produce a quite smooth vacuum signal and a fluctuating gauge would indicate further inspection.On the plus side you do have an 02 sensor, that should indicate a mis firing cyl. as a lean condition.

art leong · 09-26-2011, 02:53 PM

Upon further inspection I see the rockers have been wearing where they make contact with the valve.
Going to pull the head now to get a better look at the valves.

Daran Summerton · 09-28-2011, 09:29 AM

Why not change the oil back first? Lifter collapse or just rings not happy with 0w sounds possible.

FED 387 · 09-28-2011, 10:53 AM

artie sent u a pm--FED387

NewHemi · 09-30-2011, 06:19 PM

We collapsed a lifter between winning class at Sports Nationals, and our first round of Eliminations. Fortunately, we got it apart and back together before we got called to staging...

But I am just saying that to say that as bad as that collapsed lifter sounded, it would seem like you would really hear it and know something bad happened.

Good luck Art, I know you will get it.

David
The New Hemi Guy

09-26-2011, 08:40 AM	#1
buzzinhalfdozen Senior Member Join Date: Sep 2006 Location: Bellevue Ohio Posts: 984 Likes: 0 Liked 11 Times in 8 Posts	Re: I think I found my problem???????? Art, I'm so glad you found this, been gone to the Sportsnats with my kid so been out of touch. As agrivating as this was for you it did at least allow you to look deeper into the operation of your system. Knowledge is power and the more we understand the easier problem solving becomes. Nice job. Joe __________________ Joe Buchanan SS/BX 3117

09-26-2011, 11:49 AM	#3
buzzinhalfdozen Senior Member Join Date: Sep 2006 Location: Bellevue Ohio Posts: 984 Likes: 0 Liked 11 Times in 8 Posts	Re: I think I found my problem???????? Art, that's not good news. One way I have found intermitent valve issues ie. valve sticking in guide weak spring ect. is by doing a running compression test. This requires removing the schrader from you tester so it doesn't hold pressure, running the engine you will see the needle fluctuate wildly however if you look at it closely you will see where it hits its high number. watching for the needle to not go to that high number at times is an indicater that something in the valve system is amiss. I would think this test would pick up a lifter thats bleeding down as well. As far as it making a noise I'm unsure of the answer to that as the cam is always in contact with the lifter and it bleeding off and not moving the follower, I would think would result in no detectable noise, it simply would not move the valve.On stock engine these problems are easier to find with a simply vacuum gauge as they produce a quite smooth vacuum signal and a fluctuating gauge would indicate further inspection.On the plus side you do have an 02 sensor, that should indicate a mis firing cyl. as a lean condition. __________________ Joe Buchanan SS/BX 3117

09-26-2011, 02:53 PM	#4
art leong VIP Member Join Date: Dec 2001 Location: Richmond Hill, Georgia Posts: 2,003 Likes: 0 Liked 1 Time in 1 Post	Re: I think I found my problem???????? Upon further inspection I see the rockers have been wearing where they make contact with the valve. Going to pull the head now to get a better look at the valves. __________________ Art Leong 2095 SS

09-28-2011, 09:29 AM	#5
Daran Summerton Senior Member Join Date: Jun 2003 Location: Las Vegas nv Posts: 600 Likes: 18 Liked 66 Times in 37 Posts	Re: I think I found my problem???????? Why not change the oil back first? Lifter collapse or just rings not happy with 0w sounds possible. __________________ 72 cutlass

09-28-2011, 10:53 AM	#6
FED 387 VIP Member Join Date: Jun 2006 Posts: 3,416 Likes: 522 Liked 330 Times in 178 Posts	Re: I think I found my problem???????? artie sent u a pm--FED387

09-30-2011, 06:19 PM	#7
NewHemi Senior Member Join Date: Dec 2009 Location: Ohio Posts: 472 Likes: 0 Liked 1 Time in 1 Post	Re: I think I found my problem???????? We collapsed a lifter between winning class at Sports Nationals, and our first round of Eliminations. Fortunately, we got it apart and back together before we got called to staging... But I am just saying that to say that as bad as that collapsed lifter sounded, it would seem like you would really hear it and know something bad happened. Good luck Art, I know you will get it. David The New Hemi Guy