C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Overheating problem

Thread Tools
 
Search this Thread
 
Old Jul 20, 2024 | 03:05 AM
  #1  
moodydavid16's Avatar
moodydavid16
Thread Starter
Advanced
All Eyes On Me
Liked
 
Joined: Mar 2023
Posts: 80
Likes: 4
From: Salt Lake, Utah
Default Overheating problem

Hello, I am having a problem with overheating. On my 1986 (l98). Yes car is actually getting hot. I cleared the radiator, water pump pumps and isn’t leaking. have a new thermostat, coolant, radiator cap, and cooling fan. Test for combustion gas in coolant came back negative, system vacuum filled and bled multiple times. Fan is always on and still overheats. Used to run around 175 now climbs all the way to mid 230s before I pull over to cool it down. Oil gets to 250-270. It seems like the oil is heating up first and driving the temperature of everything else up as well. Has anyone else had a similar problem? Where should I look next?
Reply
Old Jul 20, 2024 | 03:06 AM
  #2  
moodydavid16's Avatar
moodydavid16
Thread Starter
Advanced
All Eyes On Me
Liked
 
Joined: Mar 2023
Posts: 80
Likes: 4
From: Salt Lake, Utah
Default

I don’t want to just slap a bigger radiator in there and call it a day. The system has and should work with the stock components.
Reply
Old Jul 20, 2024 | 06:08 AM
  #3  
'78CorvetteS.A.'s Avatar
'78CorvetteS.A.
Drifting
Shutterbug
Community Favorite
Top Answer: 3
 
Joined: Nov 2018
Posts: 1,720
Likes: 621
From: USA
Default

Is the original catalytic converter still on the car? I would take some temperature readings of the exhaust pre-cat, cat, and post-cat. If it's severely plugged, this can drive up oil temps. Just a thought, good luck👍
Reply
Old Jul 20, 2024 | 08:34 AM
  #4  
Cruisinfanatic's Avatar
Cruisinfanatic
Le Mans Master
Supporting Member
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2004
Posts: 6,213
Likes: 694
From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
Default

Originally Posted by moodydavid16
Hello, I am having a problem with overheating. On my 1986 (l98). Yes car is actually getting hot. I cleared the radiator, water pump pumps and isn’t leaking. have a new thermostat, coolant, radiator cap, and cooling fan. Test for combustion gas in coolant came back negative, system vacuum filled and bled multiple times. Fan is always on and still overheats. Used to run around 175 now climbs all the way to mid 230s before I pull over to cool it down. Oil gets to 250-270. It seems like the oil is heating up first and driving the temperature of everything else up as well. Has anyone else had a similar problem? Where should I look next?
How did you clean the radiator? If you didn't take it out, it could look like this

Reply
Old Jul 20, 2024 | 12:50 PM
  #5  
moodydavid16's Avatar
moodydavid16
Thread Starter
Advanced
All Eyes On Me
Liked
 
Joined: Mar 2023
Posts: 80
Likes: 4
From: Salt Lake, Utah
Default

Originally Posted by Cruisinfanatic
How did you clean the radiator? If you didn't take it out, it could look like this

Yes I took the radiator completely out and sprayed water through the fins till clear
Reply
Old Jul 20, 2024 | 12:51 PM
  #6  
moodydavid16's Avatar
moodydavid16
Thread Starter
Advanced
All Eyes On Me
Liked
 
Joined: Mar 2023
Posts: 80
Likes: 4
From: Salt Lake, Utah
Default

Originally Posted by '78CorvetteS.A.
Is the original catalytic converter still on the car? I would take some temperature readings of the exhaust pre-cat, cat, and post-cat. If it's severely plugged, this can drive up oil temps. Just a thought, good luck👍
Yeah it does still have the stock cats. What temps should I be looking at if they aren’t clogged?
Reply
Old Jul 20, 2024 | 04:11 PM
  #7  
moodydavid16's Avatar
moodydavid16
Thread Starter
Advanced
All Eyes On Me
Liked
 
Joined: Mar 2023
Posts: 80
Likes: 4
From: Salt Lake, Utah
Default

Originally Posted by '78CorvetteS.A.
Is the original catalytic converter still on the car? I would take some temperature readings of the exhaust pre-cat, cat, and post-cat. If it's severely plugged, this can drive up oil temps. Just a thought, good luck👍
also I do have the air pump deleted, could this be causing an issue?
Reply

Get notified of new replies

To Overheating problem





All times are GMT -4. The time now is 02:43 AM.

story-0
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-1
2027 Corvette vs The World: Every Model vs Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-20 17:58:41


VIEW MORE
story-2
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-3
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-4
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-5
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-6
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-7
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE
story-8
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

Slideshow: Breaking down the 2027 Grand Sport, Grand Sport X, Stingray, and LS6 V8.

By Michael S. Palmer | 2026-03-26 13:48:45


VIEW MORE
story-9
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

Slideshow: 5 reasons bad drivers crash sports cars & 5 ways to avoid a costly shame!

By Joe Kucinski | 2026-03-25 16:32:55


VIEW MORE