Notices
1978 - 1996 Big Bronco  
Sponsored by:
Sponsored by:

O ring with thermostat replacement?

Thread Tools
 
Search this Thread
 
Old Jan 8, 2015 | 06:41 PM
  #1  
Matt Mariani's Avatar
Matt Mariani
Thread Starter
|
Freshman User
Joined: Dec 2014
Posts: 34
Likes: 0
O ring with thermostat replacement?

My '90 Bronco with 5.8 was running on the cool side so i bought a replacement 195F thermostat and replaced it.

The old one had no O Ring and the new one bought at Autozone didn't come with an O ring but i would think there would be one.

Anyway replaced it and still running just as cool. I am guessing an O ring was needed.

TIA for answers

Matt
 
Reply
Old Jan 9, 2015 | 10:00 AM
  #2  
Kemicalburns's Avatar
Kemicalburns
Hotshot
20 Year Member
Liked
Joined: Jul 2002
Posts: 14,285
Likes: 12
From: Bend,OR
shouldn't be an o ring anywhere. the T-stat housing should have a resesed area for the tstat to sit in, a gasket or bead of silicon round that and bolt it down evenly making sure the stat doesn't move out of that groove.

now if you are simply going by the stock gauge its not accurate at all. get a mechanical aftermarket gauge to see what the temp accurately is.
 
Reply
Old Jan 9, 2015 | 03:49 PM
  #3  
Matt Mariani's Avatar
Matt Mariani
Thread Starter
|
Freshman User
Joined: Dec 2014
Posts: 34
Likes: 0
Originally Posted by Kemicalburns
shouldn't be an o ring anywhere. the T-stat housing should have a resesed area for the tstat to sit in, a gasket or bead of silicon round that and bolt it down evenly making sure the stat doesn't move out of that groove.

now if you are simply going by the stock gauge its not accurate at all. get a mechanical aftermarket gauge to see what the temp accurately is.
Thanks.

The top hose out of the radiator and the T-stat housing show about 160F with my IR temp gun.

The truck runs cool which is why i did a compression test today. I was worried there was a cold cylinder situation but i doubt that as the compression number as decent for a 25 year old truck.

All cylinders were 148 - 150psi but cyl # 4 which was 126 psi.

I cut cardboard and covered about 80% of the radiator to get it to rise into normal. I then checked with the IR temp gun and got the above 160F off the T-stat housing and top hose which was lower (150F)

If i'm at 160 at the housing why is the T-stat opening?
 
Reply
Old Jan 9, 2015 | 04:42 PM
  #4  
Kemicalburns's Avatar
Kemicalburns
Hotshot
20 Year Member
Liked
Joined: Jul 2002
Posts: 14,285
Likes: 12
From: Bend,OR
perhaps your fan clutch is not working correctly. basicly stuck and operating all the time which may cause it to run cool. is it easy to turn the fan by hand? it should spin freely for the most part and tighten up when it gets hot.
 
Reply
Old Jan 9, 2015 | 04:58 PM
  #5  
Matt Mariani's Avatar
Matt Mariani
Thread Starter
|
Freshman User
Joined: Dec 2014
Posts: 34
Likes: 0
Originally Posted by Kemicalburns
perhaps your fan clutch is not working correctly. basicly stuck and operating all the time which may cause it to run cool. is it easy to turn the fan by hand? it should spin freely for the most part and tighten up when it gets hot.
I checked it, the fan spins or can be turned by hand with the same moderate resistance as the new fan clutch i looked at at the parts store today.

My fan spins in the very cold, is it supposed to? The new fan clutch i held today would do the same as there is moderate resistance. In other words the fan would not be still on any start up if this new clutch was installed. It felt just like mine.

I assumed they always spin even in very cold but spin faster once a certain temp is reached correct? But this seems wrong to me.

Does yours sit still on cold start ups? Mine does not, it always turns the fan even on 10F mornings like this morning. It is not seized though, i can turn the fan with my hands as i said. It feels as good as the new one i held with no slop or binding.

Thanks in advance for the help.

Matt
 
Reply
Old Jan 12, 2015 | 09:13 AM
  #6  
Kemicalburns's Avatar
Kemicalburns
Hotshot
20 Year Member
Liked
Joined: Jul 2002
Posts: 14,285
Likes: 12
From: Bend,OR
yea it will still turn when its cold.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
timmygyu
1978 - 1996 Big Bronco
1
Oct 20, 2014 09:30 AM
Macs1964F100
1961 - 1966 F-100 & Larger F-Series Trucks
6
Nov 9, 2013 06:54 PM
Jose A.
Aerostar
7
Sep 22, 2012 09:57 AM
Shooter00
1973 - 1979 F-100 & Larger F-Series Trucks
13
Aug 24, 2010 09:12 PM
So-Cal Sancho
1987 - 1996 F150 & Larger F-Series Trucks
10
Jul 11, 2009 01:41 PM




All times are GMT -5. The time now is 05:31 PM.

story-0
Rezvani's Latest Post-Apocalytic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-05-30 18:33:59


VIEW MORE
story-1
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-2
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-3
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-4
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-5
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-6
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-7
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-8
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-9
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE