L36 Upper Intake - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat

1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Thread Tools Search this Thread
Old 01-29-2006, 05:10 PM   #1

Expert Gearhead
Thread Starter
BillBoost37's Avatar
Join Date: Mar 2005
Location: Enfield, CT
Posts: 41,391
Thanks: 0
Thanked 0 Times in 0 Posts
BillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of lightBillBoost37 is a glorious beacon of light
Default L36 Upper Intake

Recently helped a member change the upper intake manifold after it failed.

Had read all the intake failure posts and Bob Dillions sleeved intake posts and thought I understood the situation and the resolution.

Here'* my understanding after having changed one. The lower intake manifold hole for the EGR gasses to go up and into the upper intake manifold sleeve..looks like it'* larger than the upper intake sleeve.

Therefore the Bob Dillions slightly larger sleeve makes much more sense and I would go that way again instead of getting another replacement manifold.
BillBoost37 is offline   Reply With Quote
Old 01-29-2006, 07:21 PM   #2
Senior Member
True Car Nut
Join Date: Oct 2002
Location: Groton, CT _NEBF 05, 06, 07_
Posts: 2,703
Thanks: 0
Thanked 0 Times in 0 Posts
markwb is on a distinguished road

Sounds very logical to me. It'* always the area in proximity of the EGR stove pipe where it enters the upper that fails over time due to high heat. That is where the sleeve comes into play.
markwb is offline   Reply With Quote
Old 01-29-2006, 09:20 PM   #3
Senior Member
Posts like a Camaro
Join Date: Feb 2005
Location: Gilroy, California
Posts: 922
Thanks: 0
Thanked 0 Times in 0 Posts
Bob Dillon is on a distinguished road

Glad you got 'er done, Bill.

I think car guys like we all are understand instinctively that plastic and exhaust gases (right from the exhaust ports, at that) are a bad combination. I don't care if coolant surrounds the EGR passage, that engineering solution makes no sense. The all-aluminum Vega cylinder block springs to mind.

I was initially conflicted about the sleeve, wondering if the metal sleeve in contact with the plastic (even though a thin coat of epoxy) would eventually burn through yet again.

For that reason, I used stainless steel, because it doesn't transfer heat as well as mild steel alloys and further, is not eroded by exhaust gases.

I also initially had to think out how to ream the EGR passage. As I'm using reamers and not a drill, I have control. My initial thought was to make the stainless sleeve a light press fit, but then I worried that the sleeve might expand enough to crack the plastic.

So, I now use a reamed hole that'* about .010 larger than the sleeve and goop up the sleeve really well with epoxy. I also roughen the inside of the EGR passage and the outside of the sleeve so that the epoxy has enough keyways for the repair to remain (hopefully) permanent.

Guy, there aren't any failures yet, and I have 30K on mine, but keep in mind we're all part of an experiment, that thankfully seems to work so far.

By the way, when the EGR passage is reamed out to .885, the openings to the coolant passages are quite small and at the 9 and 3'oclock position. I suspect that this is how the new Dorman was construcuted-with additional material in this area.

If that'* so, it just means the Dorman will last a bit longer before failing.
Bob Dillon is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Anyone tell if this is a upper control arm or an entire upper, lower, knuckle? GunsOfNavarone General GM Chat 4 11-26-2014 01:45 PM
3.5L upper intake on 3.4L lower intake/engine LA1 Chevrolet 3 10-24-2014 02:32 PM
L36 upper intake failure firebuick General GM Chat 4 07-20-2007 10:09 AM
Critical L36 Upper Intake Manifold Info....for 2000+ owners willwren General GM Chat 37 04-16-2007 04:38 PM
Who has a ruined upper L36 intake they'll ship to me? Bob Dillon 1992-1999 7 03-07-2005 12:58 PM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -4. The time now is 11:43 AM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.