Lower intake gasket PROBLEM FOUND

[Flyin Ryan]

Re: Lower intake gasket PROBLEM FOUND

Don, What kind of issues have you been having that prompted you to read up on the possible shitty gasket job from the factory?? I know ed hess in the past chased a horrible idle issue and finally chalked it up to the same deal I believe

 

[dalwine250]

Re: Lower intake gasket PROBLEM FOUND

i found mine bad [from the factory] about 6 weeks ago.for 2 years i chased a poor idle,a little stumble just off idle and a rich condition that was throwing a lean code [once in a while].vac at idle was always good tho.now it is golden.idles sweet,runs good,no codes
dave

 

[MikeRenz]

Re: Lower intake gasket PROBLEM FOUND

I tend to disagree w/ jumping on the "bad from factory" gasket bandwagon. These trucks are all almost 15yrs old, and have many miles on them. Thing wear out over time. You're not going to have an old car and not need to change some gaskets from time to time.

 

[dgoodhue]

Re: Lower intake gasket PROBLEM FOUND

I tend to disagree w/ jumping on the "bad from factory" gasket bandwagon. These trucks are all almost 15yrs old, and have many miles on them. Thing wear out over time. You're not going to have an old car and not need to change some gaskets from time to time.

I am with renz. I can't see anyone putting up with a leaking intake gasket when the truck was under warranty. One thing that has surprise me a little bit is that SBC V8 often have intake gasket leaks on the front or rear of the intake. It seems like I rarely see those problems with 4.3's.

 

[dalwine250]

Re: Lower intake gasket PROBLEM FOUND

in my case every owner of my truck had the same problem.when i pulled the lower intake off you could clearly see where the rubber on the gasket had pushed down into the port.there was a line on the gasket from being squeezed.it did get worse when i went 3 bar and upped the boost.forcing me to find out what was up.my truck was a virgin when i got it .every owner just put in a new o2 senser.i would run a lil better,then gradualy get worse.i,m not doggin pas or anything.other than that my truck has been trouble free.105k and countin.25k in the last 2 years.
dave

 

[Don W.]

Re: Lower intake gasket PROBLEM FOUND

Don, What kind of issues have you been having that prompted you to read up on the possible shitty gasket job from the factory?? I know ed hess in the past chased a horrible idle issue and finally chalked it up to the same deal I believe

Well call it what you want. The pictures tell the story. Here’s a brief history.

For prolly over a year the truck has had a slight miss at idle but ran fine otherwise. Pulled good (although this year I never approached the 13.000 that I ran late last year) and it ran just fine at anything off idle. Only other symptom was an occasional slight hesitation coming off idle. End of ’06 comes and it’s smog check time. Passes 2500 RPM test just fine, fails miserably at idle. HC’s 344, allowed 120. So I start throwing parts at it.

New:

3” highflow cat, muffler delete.
EGR valve
2 new 02 sensors (first one was bad)
Rebuilt throttle body (my original shaft was loose)
Rebuilt dist (paid a very well respected local shop to tell me my original one was, in fact, bad. The also tested the o2) Paid again to verify that ign was “perfect” and o2 good.

Even bought a MSD 6al. (Ran a little better, started much better) but,

after all that and many free “manual” tests at my smog guy that same old miss is still there. Made lots of progress on the idle test but still not quite there. (I owe that guy)

Last resort, send my other set if injs to Mike at RPM, they flow perfect. So I’ve got the top of the engine apart the install them and the old gut feeling says you’re this far, and I’ve seen dalwine250’s post so off comes the lower intake and there it is.

BTW I also reset the lifter preload and found nothing amis.

After everything is back together it's gonna feel like a first date at the smog shop, it darn well better pass this time.

 

[gjp]

Re: Lower intake gasket PROBLEM FOUND

gaskets went out today. should have them tomorow.
not sweating the money. Just buy me a few beers one day and I call it even.

My truck had 95k and a miss at idle. My gaskets looked fine. Idle is rough but no miss anymore. So far.

 

[Flyin Ryan]

Re: Lower intake gasket PROBLEM FOUND

Well call it what you want. The pictures tell the story. Here’s a brief history.

For prolly over a year the truck has had a slight miss at idle but ran fine otherwise. Pulled good (although this year I never approached the 13.000 that I ran late last year) and it ran just fine at anything off idle. Only other symptom was an occasional slight hesitation coming off idle. End of ’06 comes and it’s smog check time. Passes 2500 RPM test just fine, fails miserably at idle. HC’s 344, allowed 120. So I start throwing parts at it.

Don,

Thanks for the reply.. so basically it idled a little shitty and you have some off idle hesitation? hmmmm has me wondering about me lower intake gasket

 

[Don W.]

Re: Lower intake gasket PROBLEM FOUND

I tend to go slow and I had my lower intake off in a couple of hours. Remember some of that time was spent debating with my gut.:lol: I hindsight I shudda checked it a long time ago.

 

[mrweelr]

Re: Lower intake gasket PROBLEM FOUND

I did this a few thousand miles ago, when I did the headers, turbo, A2A, tranny and all of my other mods. Basically, truck had about 74K miles on it and I figured I might as well change the gaskets since they were probably not in the best shape anymore. Sure enough, they were rotted out and contorted when I pulled the intake off. Surprisingly, the lifter valley was amazingly clean...must have been those frequent Mobil 1 oil changes. I took my time cleaning everything and used a new set of Victor Reinz gaskets from Mike at RPM. Torqued everything to the proper specs per the service manual and there are zero leaks plus the truck idles perfectly. I used Permatex gray RTV on the front, back, and corners of the new gaskets and also coated the bolts before reinstalling them. I highly recommend doing this for piece-of-mind if you have high miles or suspect a vacuum or coolant leak. Here are some pics, motor is still bone stock with 77K miles:

 

[Don W.]

Re: Lower intake gasket PROBLEM FOUND

Thanks,

Yup, mine is that clean also. Mobile 1 I assume...