Monte Carlo Forums

Go Back   Monte Carlo Forum - Monte Carlo Enthusiast Forums > Your Ride > Engine/Transmission/Performance Adders
Sign in using an external account
Register Forgot Password?

Welcome to the Monte Carlo Forum - Monte Carlo Enthusiast Forums.
If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

LinkBack Thread Tools Search this Thread
Old 04-17-2012, 06:36 PM
Join Date: Apr 2012
Posts: 2
Default 98 Monte ls 3100 Antifreeze leak

Car started overheating, noticed that my antifreeze was running low I had filled it just a week before. I fill it up again to find the leak, it is coming from the left side of the engine by the pulleys but not the waterpump farther back towards the top but cannot see it only see it leaking pretty heavy out of there. Hoses are good, radiator is good, waterpump is good, thermostat is good and housing. The oil is not mixed with coolant. I just cannot figure it out. Any Ideas?
Reply With Quote
Old 04-17-2012, 08:32 PM
Join Date: Jun 2010
Posts: 88

Got a pic or anything where the coolant is pooling? Not to combat your assertiveness or anything, but if it truly isn't all the things you said it isn't, you've not left yourself many options. Lower intake manifold gasket possibly? You'd hardly be the first Chevy to have this issue.
Reply With Quote
Old 04-17-2012, 09:09 PM
zzapultimate's Avatar

Monte Of The Month -- June 2012
5 Year Member3 Year Member1 Year Member
Join Date: Nov 2008
Location: Iowa
Posts: 2,026

LIM gasket would be my guess. Very common issue.

Click Here for Photo Album!!

~99 LS -- 200K~
Not your standard LS -- Check out a mods list Here!
Reply With Quote
Old 04-17-2012, 11:18 PM

Join Date: Sep 2011
Location: Minnesota
Posts: 370
James nordby Beev manster

Does anybody know if the 3100 has the coolant elbows ? If it does check them to
Reply With Quote
Old 04-18-2012, 01:15 AM
Join Date: Apr 2012
Posts: 2

I will try and get some pictures, Its very hard to tell because it is leaking down and out its kinda behind a pulley but is not behind the waterpump pully.
Reply With Quote
Old 04-18-2012, 09:40 AM
Join Date: Jun 2010
Posts: 88

My wife's 3400 LIM was always leaking internally then about three days before we got married it finally started leaking externally. I gave it to her dad when we left for Hawaii and he took care of it while we were gone; worked out great.

Anyway, point of that statement, when it finally started leaking externally I couldn't figure out where it was coming from so I dried up all the coolant then stood there and watched it run for 10 minutes and sure enough I was able to see the coolant come out between the intake/block interface. You may just need to stand there and watch it.
Reply With Quote
Old 04-18-2012, 10:40 PM
Join Date: Jun 2009
Location: St. Louis
Posts: 356

the 3100 does not have those retarded coolant elbows. 99% chance it's the l.i.m. gasket. replace right meow.
Reply With Quote
Old 04-19-2012, 10:02 PM
The_Maniac's Avatar

Monte Of The Month -- December 2011
3 Year Member1 Year Member

Join Date: Apr 2010
Location: Mentor, Ohio
Posts: 7,430

3100 does not have coolant elbows.

Usually a water pump failure leaves a nice WET line right above the serpentine belt on the hood insulation. If you're not seeing anything there, probably NOT the pump.

Best thing to do, with the car cold and a radiator pressure tester (hit up the parts store for a loan-a-tool), pump it up and LISTEN for hissing. To be honest, based on the description provided, my thoughts are lower intake gasket (the coolant ports on on the far outsides of the intake, it's NOT uncommon to have it blow in a manner that most or all coolant exits the engine and never enters the oil). If you use a radiator pressure tester, look where the LIM and heads meet, you'll probably see coolant escaping.
Check out my websites below:
- 1984 Camaro Z28 5.0 Liter HO Restore Project/Big Toy
- 2004 Monte Carlo SS 3800 N/A See website for MOD List
- 2002 Grand Am GT - Current daily driver
Reply With Quote
Old 04-19-2012, 10:02 PM

3100, 98, blown, carlo, chevy, coolant, elbow, elbows, intake, internally, leak, leaking, marlo, monte, pullys, radiator

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 On
Pingbacks are On
Refbacks are On


Featured Sponsors
Vendor Directory
Our Sponsors

All times are GMT -5. The time now is 08:47 PM.

Internet Brands, Inc.

SEO by vBSEO ©2010, Crawlability, Inc.