Fixing a Rocker Arm
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Fixing a Rocker Arm
I have been going through an Odyssey of events that started with an engine miss. I found a broken push rod and decided to do some upgrading while I am in there, in the form of yellow valve springs.
I have done the compression test and have reading form a high of 170 to a low of 155. The cylinder with the broken push rod was 165 so I am thinking "no bent valve". I bought a leak down tester and am in the process of doing that test if I can figure how to make the work.
Anyway I pulled all the push rods and checked them for roundness, and found they were all OK. The rocker arms seem to be fine. They move freely with no binding that I can feel. But there was one rocker arm that seemed to have excessive side to side play. Upon further inspection I noticed that one of the end caps was sticking out about 1/8 inch. I used a "C" clamp and seated it back in place. It required pressure to move it, so I don't see in coming out again but who knows.
Has anyone had this problem and is that the proper fix, or do I hear "replace the rocker arms".
The engine is stock and with 88K miles I don't want to invest a lot of money and time in a cam and heads, just going with headers and a tune.
Any thought on what to do with the rockers?
I have done the compression test and have reading form a high of 170 to a low of 155. The cylinder with the broken push rod was 165 so I am thinking "no bent valve". I bought a leak down tester and am in the process of doing that test if I can figure how to make the work.
Anyway I pulled all the push rods and checked them for roundness, and found they were all OK. The rocker arms seem to be fine. They move freely with no binding that I can feel. But there was one rocker arm that seemed to have excessive side to side play. Upon further inspection I noticed that one of the end caps was sticking out about 1/8 inch. I used a "C" clamp and seated it back in place. It required pressure to move it, so I don't see in coming out again but who knows.
Has anyone had this problem and is that the proper fix, or do I hear "replace the rocker arms".
The engine is stock and with 88K miles I don't want to invest a lot of money and time in a cam and heads, just going with headers and a tune.
Any thought on what to do with the rockers?
Burning Brakes
Joined: May 2008
Posts: 1,147
Likes: 1
From: Mohegan Lake New York
At the very least replace the suspect rocker,if it were my car I'de bite the bullet and pop for new rockers' buy good ones & they last,plusaftermarket ratios are right on, sometimes stockers aren't true ratios,another thought if one is damaged are the rest ready to fail? and lastly you can change ratios you get the benefit of slightly bigger cam numbers withouut a cam swap
Safety Car
Joined: Jul 2004
Posts: 3,904
Likes: 29
From: Vancouver Washington
At the very least replace the suspect rocker,if it were my car I'de bite the bullet and pop for new rockers' buy good ones & they last,plusaftermarket ratios are right on, sometimes stockers aren't true ratios,another thought if one is damaged are the rest ready to fail? and lastly you can change ratios you get the benefit of slightly bigger cam numbers withouut a cam swap
And ditto for the push rods. A new set of Comp Hi techs is only about $100.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
As an alternative, have your stock rockers rebuilt by Harland Sharp:
http://www.harlandsharp.com/conversion%20kit.htm
http://www.harlandsharp.com/conversion%20kit.htm
Race Director
Joined: Mar 2004
Posts: 12,466
Likes: 886
From: Fort Wayne IN
2025 C5 of the Year Finalist - Modified
C5 of Year Finalist (performance mods) 2019
2017 C5 of the Year Finalist
2016 C5 of the Year Finalist
2015 C5 of the Year Finalist
As an alternative, have your stock rockers rebuilt by Harland Sharp:
http://www.harlandsharp.com/conversion%20kit.htm
http://www.harlandsharp.com/conversion%20kit.htm
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Thanks for all the good advice. What I have done is put a pencil to the problem.
Using GM parts then using Yella Tera and patriot parts
GM
$170 Rocker Arms $ 385 Yella Terra Ultralite Shaft Mount 1.8
$145* Valve Springs $152(Patriot Gold)
$230 Push Rods $106(Patriot hardened)
$45 Valve Seals $ 45
_____ ____
$590 $688
*zo6 yellow
Now I have to think, I will be getting more performance out of the aftermarket package for only $102 more.
Or I could cheap out and leave the push rods, replace one rocker arm but do the springs as my engine has 88K miles so the stocks must be worn. That will cost under $200.
Decisions...Decisions
BTW the car is not a daily driver I use it for open track events maybe 6 to 10 per year.
Using GM parts then using Yella Tera and patriot parts
GM
$170 Rocker Arms $ 385 Yella Terra Ultralite Shaft Mount 1.8
$145* Valve Springs $152(Patriot Gold)
$230 Push Rods $106(Patriot hardened)
$45 Valve Seals $ 45
_____ ____
$590 $688
*zo6 yellow
Now I have to think, I will be getting more performance out of the aftermarket package for only $102 more.
Or I could cheap out and leave the push rods, replace one rocker arm but do the springs as my engine has 88K miles so the stocks must be worn. That will cost under $200.
Decisions...Decisions
BTW the car is not a daily driver I use it for open track events maybe 6 to 10 per year.
Last edited by jaybar; Jan 13, 2009 at 05:13 PM. Reason: formating
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Safety Car
Joined: Jul 2004
Posts: 3,904
Likes: 29
From: Vancouver Washington
"BTW the car is not a daily driver I use it for open track events maybe 6 to 10 per year. " 
If you're anticipating that kind of use - spend the money now. Fixing the bottom of the motor after a valve train incident will be a lot more money later.
I've been running the Yella Terras, hardened push rods, and PAC 1518 springs on my track car for two years now and the peace of mind alone is worth the investment.
If you're anticipating that kind of use - spend the money now. Fixing the bottom of the motor after a valve train incident will be a lot more money later.
I've been running the Yella Terras, hardened push rods, and PAC 1518 springs on my track car for two years now and the peace of mind alone is worth the investment.
Burning Brakes
Joined: May 2008
Posts: 1,147
Likes: 1
From: Mohegan Lake New York
Not a daily driver?!?! And you're considering putting back togather a broken stock rocker?!?! DUDE,Ever hear the term penny wise, pound foolish? Trying to save some pennys now at the expense of losing an engine, yeah a broken part in the valvetrain could lead to catastrophic engine failure and you as a racer should know that. Quite frankly I'm surprisedyou asked this question as a racer you already know the answer
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Not a daily driver?!?! And you're considering putting back together a broken stock rocker?!?! DUDE,Ever hear the term penny wise, pound foolish? Trying to save some pennys now at the expense of losing an engine, yeah a broken part in the valvetrain could lead to catastrophic engine failure and you as a racer should know that. Quite frankly I'm surprisedyou asked this question as a racer you already know the answer
Thanks to all that replied. One last question, the Yella Terra rockers are shaft mounted and from the pictures is looks like they are in sets for each cylinder. Is there any head prep or is it just a bolt in. I assume the pivot strip will not be used.
Jay B
Safety Car
Joined: Jul 2004
Posts: 3,904
Likes: 29
From: Vancouver Washington
Yea, I know better. But with 88k miles I figure I am going to replace the engine in a year or so. I just wanted to put a band aid on it for the time being. But for $684 and some performance gains to boot I think I will do it the right way.
Thanks to all that replied. One last question, the Yella Terra rockers are shaft mounted and from the pictures is looks like they are in sets for each cylinder. Is there any head prep or is it just a bolt in. I assume the pivot strip will not be used.
Jay B
Thanks to all that replied. One last question, the Yella Terra rockers are shaft mounted and from the pictures is looks like they are in sets for each cylinder. Is there any head prep or is it just a bolt in. I assume the pivot strip will not be used.
Jay B
Pro
Joined: Oct 2005
Posts: 733
Likes: 0
From: Vanceboro NC
Thanks for all the good advice. What I have done is put a pencil to the problem.
Using GM parts then using Yella Tera and patriot parts
GM
$170 Rocker Arms $ 385 Yella Terra Ultralite Shaft Mount 1.8
$145* Valve Springs $152(Patriot Gold)
$230 Push Rods $106(Patriot hardened)
$45 Valve Seals $ 45
_____ ____
$590 $688
*zo6 yellow
Now I have to think, I will be getting more performance out of the aftermarket package for only $102 more.
Or I could cheap out and leave the push rods, replace one rocker arm but do the springs as my engine has 88K miles so the stocks must be worn. That will cost under $200.
Decisions...Decisions
BTW the car is not a daily driver I use it for open track events maybe 6 to 10 per year.
Using GM parts then using Yella Tera and patriot parts
GM
$170 Rocker Arms $ 385 Yella Terra Ultralite Shaft Mount 1.8
$145* Valve Springs $152(Patriot Gold)
$230 Push Rods $106(Patriot hardened)
$45 Valve Seals $ 45
_____ ____
$590 $688
*zo6 yellow
Now I have to think, I will be getting more performance out of the aftermarket package for only $102 more.
Or I could cheap out and leave the push rods, replace one rocker arm but do the springs as my engine has 88K miles so the stocks must be worn. That will cost under $200.
Decisions...Decisions
BTW the car is not a daily driver I use it for open track events maybe 6 to 10 per year.
Does this car have a stock cam in it? If so your not going to put the Patriot Duel springs on it are you?
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
I was kind of wondering about having to much spring tension but I really don't know much about spring rates etc.
Do you think with the stock cam I should stay with the ZO6 springs?
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
I need some advice from this forum before I place my order for the parts mentioned several posts ago.
One thing did come up since my last post. I did a leak down test. I had bought a two gage system that I could not get to work. I then borrowed a single gage unit from a friend who forgot how to use it. So I attached the unit to the compressor about 80psi then made the connection to the hose coming out of the spark plug hole. The gage ran up to about 10 to 11 %. At first I was getting 24% then re tightened the connection in the spark plug hole and did it again. I did the even numbers at least 3 times each and finally got them to all read in the 10 % range. Now the odd numbers. 3,5,and 7 read 10% but as much as I tired I could only get #1 to read 20-22%.
This is interesting because my original problem (a broken push rod) was in #8, which tests 'good".
So maybe my engine is not in great shape but may last a while. My oil analysis does not show blow by or coolant in the oil.
Last question, should I buy the Yella Terra or by stock rockers, (because of engine condition), and are dual valve springs worth it with a stock cam or should I just go with the yellow ZO6. I have bought an L-cheapo valve spring compressor and I am not sure it will work with dual valve springs.
Help!
One thing did come up since my last post. I did a leak down test. I had bought a two gage system that I could not get to work. I then borrowed a single gage unit from a friend who forgot how to use it. So I attached the unit to the compressor about 80psi then made the connection to the hose coming out of the spark plug hole. The gage ran up to about 10 to 11 %. At first I was getting 24% then re tightened the connection in the spark plug hole and did it again. I did the even numbers at least 3 times each and finally got them to all read in the 10 % range. Now the odd numbers. 3,5,and 7 read 10% but as much as I tired I could only get #1 to read 20-22%.
This is interesting because my original problem (a broken push rod) was in #8, which tests 'good".
So maybe my engine is not in great shape but may last a while. My oil analysis does not show blow by or coolant in the oil.
Last question, should I buy the Yella Terra or by stock rockers, (because of engine condition), and are dual valve springs worth it with a stock cam or should I just go with the yellow ZO6. I have bought an L-cheapo valve spring compressor and I am not sure it will work with dual valve springs.
Help!
Tech Contributor
Joined: Jan 2007
Posts: 19,458
Likes: 1,165
From: Dyer, IN
I need some advice from this forum before I place my order for the parts mentioned several posts ago.
One thing did come up since my last post. I did a leak down test. I had bought a two gage system that I could not get to work. I then borrowed a single gage unit from a friend who forgot how to use it. So I attached the unit to the compressor about 80psi then made the connection to the hose coming out of the spark plug hole. The gage ran up to about 10 to 11 %. At first I was getting 24% then re tightened the connection in the spark plug hole and did it again. I did the even numbers at least 3 times each and finally got them to all read in the 10 % range. Now the odd numbers. 3,5,and 7 read 10% but as much as I tired I could only get #1 to read 20-22%.
This is interesting because my original problem (a broken push rod) was in #8, which tests 'good".
So maybe my engine is not in great shape but may last a while. My oil analysis does not show blow by or coolant in the oil.
Last question, should I buy the Yella Terra or by stock rockers, (because of engine condition), and are dual valve springs worth it with a stock cam or should I just go with the yellow ZO6. I have bought an L-cheapo valve spring compressor and I am not sure it will work with dual valve springs.
Help!
One thing did come up since my last post. I did a leak down test. I had bought a two gage system that I could not get to work. I then borrowed a single gage unit from a friend who forgot how to use it. So I attached the unit to the compressor about 80psi then made the connection to the hose coming out of the spark plug hole. The gage ran up to about 10 to 11 %. At first I was getting 24% then re tightened the connection in the spark plug hole and did it again. I did the even numbers at least 3 times each and finally got them to all read in the 10 % range. Now the odd numbers. 3,5,and 7 read 10% but as much as I tired I could only get #1 to read 20-22%.
This is interesting because my original problem (a broken push rod) was in #8, which tests 'good".
So maybe my engine is not in great shape but may last a while. My oil analysis does not show blow by or coolant in the oil.
Last question, should I buy the Yella Terra or by stock rockers, (because of engine condition), and are dual valve springs worth it with a stock cam or should I just go with the yellow ZO6. I have bought an L-cheapo valve spring compressor and I am not sure it will work with dual valve springs.
Help!
Edit** Oops....sorry..you're doing a leak down...
Last edited by lucky131969; Jan 18, 2009 at 11:19 AM.
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
I need some advice from this forum before I place my order for the parts mentioned several posts ago.
One thing did come up since my last post. I did a leak down test. I had bought a two gage system that I could not get to work. I then borrowed a single gage unit from a friend who forgot how to use it. So I attached the unit to the compressor about 80psi then made the connection to the hose coming out of the spark plug hole. The gage ran up to about 10 to 11 %. At first I was getting 24% then re tightened the connection in the spark plug hole and did it again. I did the even numbers at least 3 times each and finally got them to all read in the 10 % range. Now the odd numbers. 3,5,and 7 read 10% but as much as I tired I could only get #1 to read 20-22%.
This is interesting because my original problem (a broken push rod) was in #8, which tests 'good".
So maybe my engine is not in great shape but may last a while. My oil analysis does not show blow by or coolant in the oil.
Last question, should I buy the Yella Terra or by stock rockers, (because of engine condition), and are dual valve springs worth it with a stock cam or should I just go with the yellow ZO6. I have bought an L-cheapo valve spring compressor and I am not sure it will work with dual valve springs.
Help!
One thing did come up since my last post. I did a leak down test. I had bought a two gage system that I could not get to work. I then borrowed a single gage unit from a friend who forgot how to use it. So I attached the unit to the compressor about 80psi then made the connection to the hose coming out of the spark plug hole. The gage ran up to about 10 to 11 %. At first I was getting 24% then re tightened the connection in the spark plug hole and did it again. I did the even numbers at least 3 times each and finally got them to all read in the 10 % range. Now the odd numbers. 3,5,and 7 read 10% but as much as I tired I could only get #1 to read 20-22%.
This is interesting because my original problem (a broken push rod) was in #8, which tests 'good".
So maybe my engine is not in great shape but may last a while. My oil analysis does not show blow by or coolant in the oil.
Last question, should I buy the Yella Terra or by stock rockers, (because of engine condition), and are dual valve springs worth it with a stock cam or should I just go with the yellow ZO6. I have bought an L-cheapo valve spring compressor and I am not sure it will work with dual valve springs.
Help!
Thanks,
Jay B
Burning Brakes
Joined: May 2008
Posts: 1,147
Likes: 1
From: Mohegan Lake New York
leakdown 10% not bad for a well used engine,two trains of thought here ,,10% leak ring not sealing as good as new hence lose power,BUT, less ring drag so gain power 20-22% #1 may be stuck rings, you can try take out #1 plug squirt in Marvel Mystery Oil don't be cheap with it let soak f at least a couple days longer if possible , drive for 50-100 miles le t cool retest.Before everybody writess in about snakeoil in a can in this application aand aalso with sstck hyd liffters I've used this stuff and ffor this problem it works
Thread Starter
Racer
Joined: Jun 2007
Posts: 468
Likes: 15
From: Jupiter FL
Your suggestion to try to free the ring is a good one, however I got the rocker arms off and am ready to do the valve springs then put it back together so while I could soak the cylinder I won't be able to drive it.
Now I must admit when I did the compression test and the leak down test I did them with the engine cold.
I would like to button it up but am waiting to hear from this forum as to Werther I should go with dual valve springs from Patriot or just get the yellow zo6 springs.
Any thoughts?
JayB
Now I must admit when I did the compression test and the leak down test I did them with the engine cold.
I would like to button it up but am waiting to hear from this forum as to Werther I should go with dual valve springs from Patriot or just get the yellow zo6 springs.
Any thoughts?
JayB