Failled Upper? Sound off: - Page 4 - GM Forum - Buick, Cadillac, 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.
View Poll Results: was your failed upper a...
rochester
18.60%
delphi
23.26%
i didn't pay that much attention, i was a little more worried about other things...
58.14%
Voters: 43. You may not vote on this poll

Failled Upper? Sound off:

Reply

 
 
 
Old 04-05-2005, 02:06 PM
  #31  
Senior Member
True Car Nut
 
Join Date: Mar 2004
Location: Ames, Iowa
Posts: 3,066
Thanks: 0
Thanked 1 Time in 1 Post
bill buttermore is on a distinguished road
Default

Originally Posted by jr's3800

Wow... I'm surprised to see one last that long without the failure.....

...
Yeah, I've been thinking about that too, and here'* a little more info. When I bought the car, the thermostat, a 195, would not close. The temperature on the gauge was below where it runs now with the drilled 180 I installed. I am thinking if that thermostat was running cool for a long time before I got the car, that the lower coolant temperature might have contributed to the longer life of the upper.

I have a similar suspicion regarding the failure of the lower intake gaskets on these cars. That is, that the deterioration of the plastic is caused by heat. My lower blue GM gaskets (original?) looked just fine - I saw no degradation at all. Maybe they looked so good because the engine ran cool. I'm guessing these plastic gaskets have little or no tolerance for overheating. I have also wondered if some chemical in the coolant or oil may be attacking and causing failure of the gaskets - although that, I think is less likely than heat as a means of damage. An analysis of failed lowers should help to point us toward possible causes and preventive measures.

If there is any truth to these ideas, it makes monitoring the coolant level and operating temperature even more important in these L36 engines. I think it is kinda' neat how the advice given here on BC for a long time has been right along those lines - watch the coolant, and install a 180 thermostat. This is wise risk management in conditions of uncertainty.
bill buttermore is offline  
Reply With Quote
Old 04-05-2005, 03:24 PM
  #32  
Senior Member
True Car Nut
 
Join Date: Jun 2004
Location: Glendale, AZ
Posts: 3,459
Thanks: 0
Thanked 1 Time in 1 Post
big_news_1 is on a distinguished road
Default

Is it just me? Doesn't it seem like GM should've looked into this stuff already? Lol, nobody stands behind their products anymore.
big_news_1 is offline  
Reply With Quote
Old 04-05-2005, 10:09 PM
  #34  
Senior Member
Posts like a Turbo
 
Join Date: Apr 2004
Location: Sheridan Wyoming
Posts: 210
Thanks: 0
Thanked 0 Times in 0 Posts
57chevythunder is on a distinguished road
Default

Bill, just wondering which coolant does your '95 have ?? Is it "DeathCool", GM/Texaco'* Pink Poison ?

If so, then I'm thinking that just maybe dropping 15 degrees off of the normal operating temp may be okay afterall. -up to this point, I have been totally against dropping the normal temp of 195. -due to the fact that "the hotter the better" as far as overall engine efficiency goes, including power output. (-a lot of people will probably disagree with that one, but good ole Smokey Yunick was just one of several people that proved years ago, that if we could operate internal combustion engines near the "melt down point", we could make ureal horsepower.)

Also, I have to wonder if maybe switching to a different coolant would be a good idea. -maybe something like Prestone "any-color" coolant ?? -or at least Presone "long-life."

Just wondering,,, -more speculation,,, -more unanswered questions,,,
57chevythunder is offline  
Reply With Quote
Old 04-05-2005, 10:29 PM
  #36  
Senior Member
True Car Nut
 
Join Date: Mar 2004
Location: Ames, Iowa
Posts: 3,066
Thanks: 0
Thanked 1 Time in 1 Post
bill buttermore is on a distinguished road
Default

Originally Posted by 57chevythunder
Bill, just wondering which coolant does your '95 have ?? Is it "DeathCool", GM/Texaco'* Pink Poison ?

If so, then I'm thinking that just maybe dropping 15 degrees off of the normal operating temp may be okay afterall. -up to this point, I have been totally against dropping the normal temp of 195. -due to the fact that "the hotter the better" as far as overall engine efficiency goes, including power output. (-a lot of people will probably disagree with that one, but good ole Smokey Yunick was just one of several people that proved years ago, that if we could operate internal combustion engines near the "melt down point", we could make ureal horsepower.)

Also, I have to wonder if maybe switching to a different coolant would be a good idea. -maybe something like Prestone "any-color" coolant ?? -or at least Presone "long-life."

Just wondering,,, -more speculation,,, -more unanswered questions,,,
Nah- my '95 had the green stuff. And I was wondering myself if I couldn't increase my fuel economy from the 24 the SLE is getting now by increasing temp to 192. But I haven't yet replaced the O2 sensor, and I may be getting some KR from my lifter peck, and I have been running 10% ethanol blend, all of which could be bigger factors in fuel efficiency. The anectodal evidence that cooler running may save the plastic, makes the trade-off an easy choice. I think until I learn different, I'll stick with the 180. Could be that the "melt-down" point for these plastic components is 195.

Do you think there is a higher percentage of gasket and UIM failures with Dex Cool?
bill buttermore is offline  
Reply With Quote
Old 04-05-2005, 10:31 PM
  #37  
Senior Member
Posts like a Turbo
 
Join Date: Apr 2004
Location: Sheridan Wyoming
Posts: 210
Thanks: 0
Thanked 0 Times in 0 Posts
57chevythunder is on a distinguished road
Default

WOW, administratorman, GOOD INFO !! (-and I'm betting that in the long run you'll be VERY glad that you never switched to the pink poison)
57chevythunder is offline  
Reply With Quote
Old 04-06-2005, 01:32 PM
  #39  
Senior Member
Posts like a Turbo
 
Join Date: Apr 2004
Location: Sheridan Wyoming
Posts: 210
Thanks: 0
Thanked 0 Times in 0 Posts
57chevythunder is on a distinguished road
Default

Great information. Excellent points.
I just got to wondering, why couldn't they make the gasket frames out of aluminum instead of plastic ??

(-the reason I say "frames" is that the actual gasket/sealing surfaces are the silicone beads)

Seems to me that the silicone beads are lasting just fine, but the plastic frames which are supposed to hold the beads in place are where the failures are occuring.

AND, in my mind, what would be even better yet, would be for the mfgr to cast or grind grooves into one of the surfaces, probably the manifold, to lay in the silicone bead type gasket, and completely do away with the stupid frames.

Actually, they could just use individual "O-Rings" to do all of the sealing chores, if they would just design it that way.

I'll bet the big reason they would never do that, is that it would slow down the assembly time a little bit, and add a little cost too. -So, the same old story, "Save a dollar and screw longevity and reliability."
57chevythunder is offline  
Reply With Quote

Thread Tools
Search this Thread
Quick Reply: Failled Upper? Sound off:


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

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.