Dumb valve spring question

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Jul 7, 2011 | 01:30 PM

phil hunter

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Joined: Jan 2006

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From: Temecula CA

Dumb valve spring question

OK, I'm about to change the valve springs on My LS1, but am concerned that my compressor isn't strong enough to hold up the valves. It is a portable (no tank) Campbell Hausfeld unit rated at 100 psi max and 2.5 cfm at 40 psi. Anyone know if this unit is strong enough to hold the valves up?

Thanks,

Phil

Jul 7, 2011 | 02:08 PM

ZeeOSix

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From: PNW

It sounds too weak to me. Last thing you want is a valve dropping down into the cylinder ... it would mean having to remove the head.

Why not go with the TDC method with nylon rope. I'm in the middle of a valve spring swap right now on my Z06 and that's the method I plan on using. Slower way to go, but less risk.

Jul 7, 2011 | 02:13 PM

0Tony Mamo @ AFR

Former Vendor

Joined: Mar 2004

Posts: 1,518

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From: Valencia CA

Quote:

Originally Posted by phil hunter

Technically assuming your cylinders have an average amount of leakdown, there will be little air escaping so even a small compressor would do the job. Once the cylinder is pressurized it wont care whether there is a 50 CFM compressor behind it or a 2 CFM compressor as long as valves and rings are in OK shape and the cylinder is leaking very small quantities of air.

Hook it up and see before you attempt to remove the springs....if the compressor runs constantly while hooked to the cylinder that would indicate a concern, but my guess it only occasionally kicks on and you should be in good shape.

Good luck with the swap!

-Tony

Jul 8, 2011 | 09:22 AM

baxsom

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From: Rockledge FL

thats why i use the rope thing, it is so much less worry.

Jul 8, 2011 | 02:16 PM

sgostisha

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Joined: Feb 2010

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From: Austin Texas

IF you had a tank I would say it is fine, but if anything happened and you lost power while the spring retainer was off then you would be in a heap of trouble. I would NEVER trust a compressor like that to do the job with.

Jul 8, 2011 | 02:34 PM

phil hunter

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Joined: Jan 2006

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From: Temecula CA

Hi Guys,

Thanks for the tips. I was concerned about my compressor which is why I posted. I have a friend with a 2.5 hp portable compressor, so I'm going to borrow his to do the job.

Phil

Jul 8, 2011 | 03:50 PM

vettenuts

Team Owner

Joined: Mar 1999

Posts: 22,025

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From: At the beach in little Rhody

I used that compressor once on my daughter's Nissan. Left the garage for a few minutes and when I came back there was a hole where the valve stem used to be

After the obligatory four letter diatribe I pulled the head (again). Next time I used TDC and rope. Needless to say that Nissan had some valve seal issues!!!