P1416 - check valve replacement method without intake removal?

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May 29, 2012 | 09:00 PM

#21

ZeeOSix

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Joined: Mar 2002

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From: PNW

Quote:

Originally Posted by Cybermind

I didn't have that experience. The intake seemed to torque down just fine at 44 in-lbs, and then 89 in-lbs the second go-around. 89 in-lbs is only 7.4 ft-lbs ... not much torque at all.

May 29, 2012 | 09:06 PM

#22

ZeeOSix

Le Mans Master

Joined: Mar 2002

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From: PNW

Quote:

Originally Posted by Cybermind

Well, when I finally got my air check valve out and took a look I understood that no cleaning in the world would've fixe it. It was blocked solid. No air whatsoever was getting through. The rubber diaphragm was completely hardened.

Someone needs to make these AIR check valves with silicone rubber diaphragms, which wouldn't get hard from the age and heat like the nitrile rubber diaphragms that are in them now.

May 29, 2012 | 10:05 PM

#23

Quicksilver Vert 01

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From: Somers, CT and Clermont, FL

St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16

Quote:

Originally Posted by Cybermind

The GM manual says to first torque the intake bolts at 44 in/lbs. Then go over it a second time with a torque of 89 in/lbs. Well, this was almost impossible to do. I had a hard enough time torquing to 44 in/lbs. The new gaskets are just too soft. I was completely bottomed out. It felt like the intake assembly was going to crack if I torqued any further. I stopped at 44 in/lbs. I'm pretty sure that it will be ok.

Ps: before anyone asks, yes I was using an Inch/Lbs torque wrench and not Foot/Lbs.

Hmmmmmm......... Something doesn't sound right here. 44 in/lbs is only slightly more than 3.5 ft/lbs!

I had no feeling of bottoming out, at the recommended final torque value, and I also used a new set of intake gaskets.

Your torque wrench may be to blame.

May 30, 2012 | 05:48 AM

#24

Cybermind

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Melting Slicks

Joined: Apr 2009

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Quote:

Originally Posted by Quicksilver Vert 01

You may be right. The torque wrench may have been off. But, it was fairly new and never dropped. Oh well, it's too late to retorque them now considering that there's threadlocker on the bolts. I'm not too concerned since the gaskets are very meaty and should be providing a proper seal regardless.

May 30, 2012 | 06:27 AM

#25

lucky131969

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Joined: Jan 2007

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From: Dyer, IN

Quote:

Originally Posted by Cybermind

You may be right.

No "may" about it. Time for a new torque wrench.

Jun 1, 2012 | 11:43 PM

#26

Quicksilver Vert 01

Tech Contributor

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From: Somers, CT and Clermont, FL

St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16

Quote:

Originally Posted by Cybermind

Oh well, it's too late to retorque them now considering that there's threadlocker on the bolts.

I disagree!

The manifold bolts can still be removed, cleaned of old thread lock compound, and reinstalled at the specified torque value.

Jun 2, 2012 | 09:35 AM

#27

madmatt9471

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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----

Quote:

Originally Posted by Cybermind

I just put everything back together and no more P1416 code. I just have a few more thoughts on my intake removal experience.
The GM manual says to first torque the intake bolts at 44 in/lbs. Then go over it a second time with a torque of 89 in/lbs. Well, this was almost impossible to do. I had a hard enough time torquing to 44 in/lbs. The new gaskets are just too soft. I was completely bottomed out. It felt like the intake assembly was going to crack if I torqued any further. I stopped at 44 in/lbs. I'm pretty sure that it will be ok. I did use thread locker.

Well, that's it. Job done. Thank you all for your help.

Ps: before anyone asks, yes I was using an Inch/Lbs torque wrench and not Foot/Lbs.

I'm sorry but this has been bugging me for a while and I just have to say it:

There is "A" need for 'Thread Locker' on the manifold bolts according to the manuals

- IF you do the torquing pattern like GM states you will be fine and the bolt will work and as you stated you 'ARE' using INCH pounds you will be fine!

My suggestion is when you have time go and remove the bolts clean them off and torque them back to the GM specs!

What grade 'Thread Locker' did you use? Perhaps you can go to the post and name the grade - Green, Blue, which strength you used!

Thank you for the input you have - I do like that you re-located the check valve that is awesome and a good idea for anyone in the future! a BIG thumbs up!

Thanks,Matt

Last edited by madmatt9471; Jun 2, 2012 at 12:00 PM. Reason: fixed per Lucky

Jun 2, 2012 | 11:15 AM

#28

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by madmatt9471

What you did will not hurt and you did a good job but I hope that others do not use 'Thread Locker' on their manifolds following your pattern - WHY?

So to be clear, you are finding fault with those who actually follow the service manual procedure?

For those reading, the service manual DOES call for threadlocker on the intake bolts, and the correct color is blue.