DIY intake questions

[Suburban-97]

After a few days of intermittent work, I finally have the intake manifold off for replacing the intake manifold gasket, distributor gear and other smaller parts and gaskets. I took maybe 50 pictures all together and I will start a new thread documenting everything I did, from a non-Pro point of view.. Remember, I am NOT a mechanic, but somehow I managed to do it without help.

Right now I am right in the middle of the cleaning stage. Upper manifold is clean already, looks almost like new. Today I am cleaning the block and the aluminum intake manifold.

I have two questions for the experienced among you:

1.) I am using the Fel-Pro MS98000T PermaDryPlus gasket set. One of the few installation tips that came with this set says: "INSTALL SIDE RAIL GASKETS DRY WITHOUT SEALERS". Does that mean that I only apply a 1/4" bead of RTV to create the end seals and nothing else? No RTV at all around ports, or along the gasket? Not even a little tiny smear?!?

2.) Am I supposed to clean the fuel injectors on the lower intake manifold too?

Thanks!

[Suburban-97]

..and about the A/C bracket: Yes, it is possible to carefully pry the bracket forward after removing the 4 bolts in front. I did exactly that and I was able to expose the intake manifold bolt that was hidden below it. I have a very nice picture of that and I will post it in my thread when I am done.

[Suburban-97]

..and again on that A/C and power steering bracket issue..

You can pry the bracket forward as I mentioned in my previous post, but that's only good for giving you some limited access for loosening the lower manifold bolt hidden behind it. It doesn't give you much room to play with..
..but when it comes to dropping the manifold back in place you WILL need that extra room.. Remember my words!

At first (after removing the A/C compressor from the bracket and taking care of the 3 bolts and the 1 stud in front of the bracket,) I was laying under the truck, wondering which 2 other bolts I need to unscrew. I could not find them and decided to try the pry method. I was then indeed able to remove the manifold bolt and remove the entire manifold, but I remember that I had to do a little twisting and turning and somehow I got it out and off the block.

Before I applied the new gaskets and sealer, I did a lot of 'dry practicing' yesterday and today, trying to simulate dropping the manifold back onto the block. What I thought might be easy to deal with and twist the manifold back onto the block, turned to be a pain in the butt.. I kept bumping into that effin' bracket and just wasn't able to put the manifold back on.
I finally gave up and decided to go back underneath the truck. This time I took plenty of halogen power with me and discovered the two missing bolts. I took one off, loosened the second one and VOILA!!!

All of a sudden I was able to slide the bracket forward as far as I wanted. I took very detailed pictures of those bolts, their location, the forward sliding A/C bracket and all that, and I will come back when I am done and start a new thread on my intake manifold project for all the non-mechanic-DIYers among you I promise!

PS - As of tonight, my intake manifold is back where it should be, new gaskets in place, torqued to Fel-Pro specs (50-100-132). While waiting for the sealer to cure (24hrs), I will put the beast back together.. and promise my wife that's I'll never do it again myself
I sure want to hope so!

[Suburban-97]

I am done with my repair!!!

I promised to start a thread about the intake manifold gasket replacement, and I did.., but I didn't realize that this is a Tahoe forum.. I started the thread in the Suburban forum, since my repair was performed on a Suburban.

Below is the link to my thread. I hope it helps someone. Click on the underlined words with links to see the pictures. Some of them might be interesting to people who do this repair for the first time.
Don't know how the A/C bracket slides forward, or what the distributor gear looks like? I took those pictures and it is all been done in the process of replacing my intake manifold gasket. Have fun and let me know what you think.



>>> Intake Manifold Gasket (my own Do-It-Yourself experience) <<<

Suburban-97

[jon-boy]

I changed the intake gaskets on my tahoe this weekend and cannot get the fuel lines back in right on the fuel metering block. Would anybody happen to know the order of the o-rings and spacer that go on the high pressure line and the return line? I made a novice mistake and didn't check to make sure that everything was out and the order that they were in. Now when I turn the key on fuel sprays everywhere. I have tried to find a breakdown drawing of the assembly but have not had any luck. Any help would be greatly appreciated.

[grumpy5]

I just have one small suggestion to make the job a little bit easier. I have a3/4 ton suburban, and when I was done with my intake my back was killing me from leaning over the truck. A dealership mechanic told me they remove the front wheels and lower the truck onto the ball joints. I havent tried it yet but it sounds like it would help things go a little faster. Like Merlin says take your time and do it right thefirst time.

[00silver]

Originally Posted by GMMerlin

1. LOOK..take a look at the intake..are there witness marks on the bolts?
Are there areas around where the manifold bolts to the head that are cleaner then the rest of the engine?

a. the gasket has gone thru a few revisions over the years..I believe the new factory gasket is black with metal "plugs" next to the bolt holes

b.I don't quite understand this one, but..GM recommends that a bead of sealer go across the engine block between the heads. I just put a small drop on the head itself to seal the corner where the gasket meets the block.....GM gray silicone or Permatex gray silicone sealers work the best IMHO

Most importantly, the bolt threads need to be cleaned and a small amount of blue loctite is to be applied to the threads when the bolt is installed...torque the bolts to 11ft/lbs

1. I'm confused, AllData says to torque bolts to 44 on first pass and then to 89 on second.
2. Also confused about the bead of sealer across block. This is just to seal between the intake and block???

[tmon103]

I did this job last summer and didn,t know the timing is all through the computer now.I marked the outside of the distributer housing but stupid me did not note the position of the rotor.When the distributer whent back in it was one tooth off.The truck was started and I imediatly knew what was wrong and found TDC and repositioned the distributor and got it back to where I think it was.Since then I have had trouble code p0340 and a hard ignision miss around 50 and 70 mph.I do not have the means to time the computor,any thoughts?
Don't make the same mistake , mark the distributor inside and out.
Tmon

[tmon103]

I did this job freelance on my 98 sierra in august and it was not fun,wish I knew about this forum then!
My question is this:would it help at all to re-tourque the intake bolts periodicaly(maybee once a year)to keep even preasure on the mating surfaces or would you be asking for trouble?
Just a thought.
Tmon

[GMMerlin]

Originally Posted by tmon103

I did this job freelance on my 98 sierra in august and it was not fun,wish I knew about this forum then!
My question is this:would it help at all to re-tourque the intake bolts periodicaly(maybee once a year)to keep even preasure on the mating surfaces or would you be asking for trouble?
Just a thought.
Tmon

If done properly, the bolts should have Loctite on them and be properly torqued.

[jonnik]

When I did my Tahoe intake gaskets, I used 4 wooden dowels (slightly smaller diameter than a pencil) in the corner bolt holes to act as a guide for the manifold. Worked great! No slipping gaskets or smeared RTV. It might also be worth the money to replace the fuel pressure regulator if you split the upper and lower manifolds, fairly cheap insurance.

[sa200]

Anyone have an idea what percent of vortec 5.7 engines had intake gaskets replaced by the time they have 150k????

[LastOne]

Originally Posted by sa200

Anyone have an idea what percent of vortec 5.7 engines had intake gaskets replaced by the time they have 150k????

I would guess 75% or better. Too bad GM would not do any sort of help to us owner's. That is why I bought a new Honda for my wife. No more new $$ to GM from me.

[RainRider]

96 5.7 CSFI 150,000 miles Helms manual:
Replaced my fuel pressure regulator this weekend (along with 2 injectors after breaking the poppet valve retainers - man, those things are brittle after they've been in there for a while)
I was surprised at how much carbon residue, from the egr system I would assume, was in the upper intake. Used to carbureted motors, I assume that this accumulation is from the upper intake being "dry," with the absense of a gasoline mixture washing some of the residue away, it just builds up.
It may be in there, but I didn't find sufficient info re o-ring/spacer placement for where the fuel lines plug into the fuel injection body assembly. I also found no mention of the small o-rings in the connection of the fuel lines at the firewall. Luckily, they were still on the lines when I hooked them back up.
All went well, and reseting the "Check Engine Soon" with the scanner showed all ok.
Just comments. . . but I still need to find a source for the poppet valve retainer instead of the whole injector assembly for next time.
RR

[radioman2002]

Well I have done mine a few times because of various problems with the engine, including a total rebuild.
First I remove the unibelt, then the AC compressor, without bleeding it and flip it over to the passenger side wheel inner fender. (Make sure you move it back before closing the hood) The alternator is removed from the belt tensioner bracket, then I remove the whole tensioner assembly. Remove the heater lines to the water pump and intake. Then I don't remove the PS pump from the bracket assembley, I remove all but one bolt and pull it away from the engine far enough to work on the intake. Remove the air box wiring and air box from the TB, remove the brackets that hold the throttle and cruise cables, disconnecting the cables at the TB. Disconnect the fuel lines back at the transmission, with fuel line wrenches. Unplug the wiring assembly from the upper intake, and all the sensors, remove the distributer, and then start removing the intake bolts, putting them in order on a piece of cardboard with a drawing of the engine. ( I also do this with all the bolts removed from the engine) To make the removal of the intake easier, you have to remove or loosen at least one valve cover.
BTW this isn't a step by step, you are going to have to find all the little parts that are attached to the engine and intake as you go along. I like making a drawing of what I am doing while doing it, I also like to take digital photos as I go along. It isn't a hard fix just a long one untill you get comfortable with doing it. My first time took 8 hours, that last time when I installed are built engine took less than 2.