• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

Upper Intake Manifold Replacement [*]

03GPScottyd

03GPScottyd

New member
(use for HV3 - High velocity intake insert)

This HOW TO write-up on Installing an Intake Gasket has been added to the How To section and can be found HERE
 
Last edited:


man I sure am glad for all the how-to's. But is there any chance any of these have pictures with them? A lot of times a picture can make a world of difference when someone is following text and may not have the visual you would hope they have.
 


Do you have any experience with the lower intake manifold? I cannot get mine off, and do not know if there is a bolt hidden somewhere or if it is just really stuck on there.
 
I worked on it in my father-in-law's shop and then went away for the weekend and he could not stand having it in his shop knowing we could not figure out how to get it off, so he worked on it some more. Turns out there were two more bolts from the inside that were covered by oil and once he got these off it came off no problem, so now I get to put it all back together without DexCool.
 


Yep, the link isn't working for me either. I have a coolant leak that I believe is coming from the UIM. Was hoping to read through the HOW-TO before I tear into it.
 
What do you guys need? I probably have most pics and can walk you through almost anything with my eyes closed, blindfolded, no car around and my ears covered. :th_lipssealed2:
 
1. Disconnect negative battery cable
2. If UIM only, no need to drain coolant. If doing LIM gaskets at same time (always suggested), drain the coolant.
3. Unhook the electrical from the TB and remove TB cables from TB.
4. Remove TB, looking at it from the front of the car, if there's a little metal bracket held on by an 8mm bolt, then remove the bolt and push the bracket toward the front of the car. Disconnect any vacuum lines to the TB gently. Remove the three 10mm nuts holding the TB to the UIM. Wiggle TB out from around the POS bracket.
5. Remove 10mm nut and bolt holding EGR shield to motor.
6. Using a 15mm untension the accessory belt.
7. Remove alternator (13mm for battery cable), finger for the electrical connector, and depending on your year either 13mm or 15mm bolts.
8. Disconnect map sensor (this is the sensor that is on the cap of the UIM next to the alternator)
9. Using fingers or needle nosed pliers, remove fuel lines from fuel rail.
10. Remove 4 10mm nuts holding the fuel rail to the LIM. Remove rail/injectors from motor.
11. Gently remove brake booster vacuum line from UIM. It is held in with two clips. There may be a vacuum line on the piece.
12. Remove a bunch of 8mm and a couple of 10mm bolts that hold the UIM to the LIM.

Evap soleniods and or some misc vacuum lines may be in the way during the steps. Work with them,.

Torque specs:
Plastic UIM bolts: 89 inch lbs
TB nuts: Little past snug, I want to think it's about 120 inch lbs
 
BillBoost - Thanks. The son and I replaced the UIM gasket last night and those instructions are right on. Unfortunately, the vacuum lines at the rear were brittle and basically fell apart when we removed them so they were probably leaking to start with. Also had a fuel connection leaking so replaced the connections while we were in there. Heading to the store for some vacuum line this morning to finish it up. When we do this again to replace the UIM and fix the LIM with a Ken-Co Ind. plenum sleeve, it should go a lot smoother. Thanks again.

Mike
 


Glad to hear it Mike. A couple of things you should know about that plastic upper.

The only real issues with it are either a TB gasket leaking or the famous cracked UIM that spews gallons of coolant into the motor. The second part, can be permanently cured by plugging the coolant ports in the LIM. This can be found in a thread by me on "how to mod a lim". It also goes into opening up the side cover area to offset the blocked coolant. I've never heard of anyone having an iced up TB and needing the coolant going to it. Plus, if any one ever looks at how much coolant enters the TB..it appears to be very very little. I've run blocked coolant many years and it's never been an issue. By blocking that, you could reuse your existing UIM and never worry about it failing.
 
Ended up going to the Chevy dealer and picking up a new plenum. Not too expensive and if it gets my son through college (about 55,000 miles worth of travel over the next 3.5 years) I'll be happy. I will definitely keep the idea of blocking the coolant passages in mind though if we have more problems. We live in Texas and icing hasn't been a big problem!

Mike
 
You must log in or register to reply here.
Back
Top