is this LIM/UIM gasket failure? - 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.

Reply
 
 
 
Thread Tools Search this Thread
Old 10-19-2007, 05:57 AM   #1
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: May 2003
Location: San Diego, CA
Posts: 203
Thanks: 0
Thanked 0 Times in 0 Posts
grey3800 is on a distinguished road
Default is this LIM/UIM gasket failure?

For a while now, stopping quickly after starting the car in the morning, a puff of white smoke comes up from above the left fender. And Ive noticed recurring puddles sitting on the LIM shown here, when engine is both warm and cold. I always use form-a-gasket along with the paper gasket on the water pump flange so im 95% sure its not coming from there. Below you can see obvious water marks on the aluminum. This pic was taken an hour after running. What made me post this was the car had sat for two days and when i went to park in the same spot there was a small puddle of coolant.

AREA #:
(1). Always water there, the most there of them all
(2). I loosened the bolt and put form-a-gasket on it then tightened it, havent seen moisture there since
(3). Appears to be moist there alot.
(4). Sometimes moisture, obviously evidence in the watermarks.

Name:  DSC01093.jpg
Views: 2
Size:  72.5 KB

The 1st area has a bolt in there too and i also tried the trick i used in bolt 2, but no dice.
This leak isnt large enough such that i have to add coolant, coolant level remains same for the last year.
Advice/Comments? Thanks Guys.
grey3800 is offline   Reply With Quote
Old 10-19-2007, 06:16 AM   #2
Junior Member
 
Join Date: Aug 2005
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
wjcollier07 is on a distinguished road
Default

You...don't...have a L36? Or do you...

That failure is only applicable on the L36.
wjcollier07 is offline   Reply With Quote
Old 10-19-2007, 06:30 AM   #3
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: May 2003
Location: San Diego, CA
Posts: 203
Thanks: 0
Thanked 0 Times in 0 Posts
grey3800 is on a distinguished road
Default

Quote:
Originally Posted by wjcollier07
You...don't...have a L36? Or do you...

That failure is only applicable on the L36.
This is my 93SE L27.

I ask because i often find myself roaming over threads with LIM/UIM gasket failure as the title. Is it purely an L36 problem, or just that it is a known issue with the L36?

The L36 and L27 i know are different (my dad has a 98SE), but still close enough in design that i thought that gasket failure is whats causing this moisture/water to collect.
grey3800 is offline   Reply With Quote
Old 10-19-2007, 07:45 AM   #4
Junior Member
 
Join Date: Apr 2006
Location: Purgatory
Posts: 0
Thanks: 0
Thanked 0 Times in 0 Posts
Bonneville92V688 is on a distinguished road
Default

John, LIM gasket failures are applicable to the Series I also, but are nowhere near as common. I replaced mine on my '94 because they were seeping between the LIM and head near the valve cover like Grey'* #3 marker was.

Grey, with your mileage, it doesn't surprise me that they are leaking. I pulled a LIM off of a 225k L67 in the U-pull-it yard here, and the LIM gaskets looked as bad as a L36/S2 L67'* and showed signs of leaking. You definantely have a leak, but it could just be loose bolts. Check to see if they are all tightened to spec, as they can loosen up and cause leaks.
Bonneville92V688 is offline   Reply With Quote
Old 10-19-2007, 09:11 AM   #5
DINOSAURUS BOOSTUS

Expert Gearhead
 
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

Grey..how much RTV did you use when installing the thermostat? RTV in places like this can actually keep the gasket from sealing and cause a leak if the surface it'* mating to isn't 100% clean. RTV won't stick to oil. Therefore if there is enough RTV to keep the paper from making a good seal and oil...you can have a pressure leak.

Your pulling of the bolts and adding goop to them is a good idea. Those bolts are known to weep if sealant is not applied when gaskets are changed or over enough time.
BillBoost37 is offline   Reply With Quote
Old 10-19-2007, 06:40 PM   #6
Senior Member
Posts like a Turbo
Thread Starter
 
Join Date: May 2003
Location: San Diego, CA
Posts: 203
Thanks: 0
Thanked 0 Times in 0 Posts
grey3800 is on a distinguished road
Default

Quote:
Originally Posted by BillBoost37
Grey..how much RTV did you use when installing the thermostat? RTV in places like this can actually keep the gasket from sealing and cause a leak if the surface it'* mating to isn't 100% clean. RTV won't stick to oil. Therefore if there is enough RTV to keep the paper from making a good seal and oil...you can have a pressure leak.

Your pulling of the bolts and adding goop to them is a good idea. Those bolts are known to weep if sealant is not applied when gaskets are changed or over enough time.
Ive had the opportunity over the last year to try varying amounts of RTV (replaced TPS sensor 3 times this year) and the leak seems to be the same, more or less it in the end squeezes out the excess (which gets wiped off). Ive torqued and retorqued all the bolts around the affected area, even adding a extra pound or two.

Well after the car sat another 24hrs, no puddles and no moist looking areas. Perhaps it is a pressure leak. Ill be observing this much closer now, opening hood before and after using her.

Many Thanks for your input guys.
grey3800 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Second UIM/LIM failure, EGR question gm98 1992-1999 2 08-28-2008 03:42 PM
UIM and LIM replaced now leaking coolant out of UIM gasket Paul1981 2000-2005 10 12-21-2007 11:05 PM
2nd possible lim/uim failure BIchselmnop 2000-2005 3 03-20-2007 01:39 AM
What are the early signs of UIM/LIM failure? two bonnies 1992-1999 11 02-25-2007 03:14 PM
Possible LIM Gasket failure Chad V 2000-2005 11 05-06-2006 10:38 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 07:00 PM.


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.