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Old 09-14-2013, 06:24 AM
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Default Broken valve spring

Since a longer time an "irregular clear TICK tone apears on the driver`s side valve train bank, next to the distributor like cylinder 5 or 6, sometimes noticed in the sidepipe.

This morning I`ve got time to go through them to search for the problem.

Result: I find the outside spring in cylinder 6 broken. The inside spring and damper are ok.

Next problem: Which spring do I choose as replacement? No number or ident. signs can be found at the broken spring.
Spring measures: OD 1.540", Length 2.470", Length in engine with closed valve 1.850"

SBF 302, FMS J 302 Alu heads, Comp CAM 31-760-8/288R valve lift 0.586"

Regarding the recomanded springs mentioned by Comp Camp, not a single measure of the installed springs corresponds.

Some proposals are welcome.

Rico
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Last edited by cobra 53; 10-24-2013 at 02:12 PM..
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Old 09-14-2013, 06:37 AM
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One way is to remove a good spring and find someone in your area with a spring tester. They will tell you seat and open force. You can measure spring height with the good one also.

Option two is find out what cam you have and they will tell you requires spring for you heads.

Easiest is call blykins tell him to send you one. He is on this forum.
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Old 09-14-2013, 06:46 AM
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Good that you found this little problem before it got ugly, you need to get your installed height measurement as well, that way any good supplier of springs/cams will know what you need.
Also the diameter of the spring will be needed so it will seat with your retainers etc.
I would be replacing all of them if mine, a set of good springs are not to costly.
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Old 09-14-2013, 07:01 AM
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You sure the heads or springs can handle that much valve lift?
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Old 09-14-2013, 07:24 AM
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I bougth the car 2 years ago with 9300 miles on the Tacho. The car was nearly 1 year in USA for fiberglas works (most tim collecting dust).

The toch marks nov 10250 mils. Sinc I have the car here in Spain, he runs allmost well.
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Old 09-14-2013, 08:26 AM
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The big question, Why did it break? If you don't figure that out, you'll be breaking more springs, with eventual catastrophic effects.

True, sometimes stuff just breaks. But I would check a few things before pressing on.

The #1 concern would be too much valve lift. I would actually measure valve lift with a dial indicator to make sure you know exactly what it is.

Second, check for coil binding. With a valve fully open, use a feeler guage to see how close the spring coils are to each other. They should not be touching anywhere.
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Old 09-14-2013, 09:21 AM
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Quote:
Originally Posted by cobra 53 View Post
Since a longer time an "irregular clear TICK tone apears on the driver`s side valve train bank, next to the distributor like cylinder 5 or 6, sometimes noticed in the sidepipe.

This morning I`ve got time to go through them to search for the problem.

Result: I find the outside spring in cylinder 6 broken. The inside spring and damper are ok.

Next problem: Which spring do I choose as replacement? No number or ident. signs can be found at the broken spring.
Spring measures: OD 1.540", Length 2.470", Length in engine with closed valve 1.850"

SBF 302, FMS J 302 Alu heads, Comp CAM 31-760-8/288R valve lift 0.586"

Regarding the recomanded springs mentioned by Comp Camp, not a single measure of the installed springs corresponds.

Some proposals are welcome.

Rico

thats a solid roller cam....i would look deeper, before planning the attack.

check out the lifters, if you don't know how many miles are on them i would replace them now or you could have an even bigger failure in the near future. looks like that spring is too much for that cam....according to comps recom. spring specs.

like another poster said.." i would replace them all if it were mine"

i will have to second that......new springs set up right, #914 for that cam, and a new set of lifters as insurance
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Old 09-14-2013, 11:24 AM
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Thanks to all for the replys.

I am with you, the best is order a set new springs recommandet from Comp Cam to match the solid roller cam.

No. 977/16. This aloud me to use the old accessoiries.

I think it will make sens to change aswell the valve seals.

The poshrods are from Sealed power and they are in good shape.

Roller Rockers from FMS.
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Old 09-14-2013, 11:44 AM
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what about the lifters?, i would be very hesitant to re-use them.
yes they showed the 977 as another spring for that cam. i didn't look to see what the two springs differences were
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