Go Back   Ford Truck Enthusiasts Forums > Diesel > Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
Sign in using an external account
Register Forgot Password?


Pre-Power Stroke Diesel (7.3L IDI & 6.9L) Diesel Topics Only

Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
LinkBack Thread Tools Search this Thread
  #1 (permalink)  
Old 10-17-2011, 04:44 PM
giantslayer giantslayer is offline
New User
 
Join Date: Sep 2011
Posts: 11
giantslayer is starting off with a positive reputation.
I replace my Thermostat in my 86 F-250 6.9 Diesel and it's not functioning right...

About 3 weeks ago I replaced the thermostat in my 86 f-250 that has the 6.9 idi diesel w/a banks turbo and the temperure gauge seems to be running in the middle between the r and the a of normal.Is that normal? Also I replaced the lower radiator hose and when the truck has run for a while I've noticed the upper radiator hose will be hot but the lower radiator hose will be cool.Is that normal? I don't belive it is. Also I replaced the themostat w/an aftermarket one from NAPA and it had a rubber ring arond the edge which I took off so the thermostat could seat properly. Was I wrong to take that off. Also this past Saturday night I went to the store (4.5 miles) and got fuel than went inside and left the truck running and when I got back in I noticed the temp gauge was towards the high mark (L of normal). Could that be due to either a bad thermostat or air in the system? As I drove back home it did drop to the middle. AlsoHow big a job is it to replace the fan clutch and could a bad fan clutch hurt my mpg? One lat question: How do I purge the cooling system of air? I know there is air in the system. Thanks
Reply With Quote
  #2 (permalink)  
Old 10-17-2011, 05:02 PM
FORDF250HDXLT's Avatar
FORDF250HDXLT FORDF250HDXLT is offline
Diesel Junkie
 
Join Date: Jul 2006
Posts: 11,792
FORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud ofFORDF250HDXLT has much to be proud of
Quote:
Originally Posted by giantslayer View Post
Also I replaced the lower radiator hose and when the truck has run for a while I've noticed the upper radiator hose will be hot but the lower radiator hose will be cool.Is that normal? I don't belive it is.
im going to leave most of your questions for others (search too would have helped you before flush/replacing t-stat though fyi.)

hot coolant in (upper hose) - radiator does its job (radiates the heat away from the coolant) - cool coolant out/back into block (lower hose.)
so having a much cooler lower hose than the top hose is normal.
__________________
♠ Log Truck: '93 F-Super Duty (F450) XLT 1st Gen Navistar 444ci IDI Diesel w/ Intercooled 2nd Gen Banks Sidewinder Turbo, E40D, 5:13, Dually, 16' Dump ♠
♠ Chip Truck: '93 F250HD XLT 4x4 1st Gen Navistar 444ci IDI Diesel w/ Intercooled 2nd Gen Banks Sidewinder Turbo, E40D, 3.55, Dually, 9' Dump, & Plow ♠

Reply With Quote
  #3 (permalink)  
Old 10-17-2011, 05:05 PM
tecgod13 tecgod13 is offline
Posting Guru
 
Join Date: Sep 2007
Location: Western Mass
Posts: 2,209
tecgod13 is gaining momentum as a positive member of FTE.
For starters, these engines don't like aftermarket thermostats. Some people have reported success with them, most people have problems.. You should have used a the motorcraft thermostat thats specced for these trucks.

For the radiator hose question, yes thats normal. The hot water goes into the top of the radiator, and cold water comes out the bottom. The radiators on these trucks work really well. Also, since your thermostat isn't working right, its not dumping as much hot into the radiator.

I believe there is a ball in the thermostat neck that works as a checkvalve, and that will bleed the system for you. But I haven't had one apart so I can't tell you specifics, do a search or wait for other replies.
__________________
1988 F250, 7.3L IDI, regular cab, long bed, 5spd ZF
Mods: ATS turbo, 3.5 inch exhaust, superduty springs front and rear, 4 gauge A-pillar pod: boost, pyro, coolant and 4th spot is switches; was 2wd, now 4wd with Dana 60 front axle
next projects: fix/complete the 3.5 inch exhaust (tailpipe exits waaaaaay to low, and needs to be extended out from under the bed) swap to a rust free cab
Reply With Quote
  #4 (permalink)  
Old 10-17-2011, 05:42 PM
starmilt starmilt is offline
Post Fiend
 
Join Date: Oct 2007
Location: Faibanks Ak.
Posts: 10,503
starmilt has a very good reputation on FTE.starmilt has a very good reputation on FTE.starmilt has a very good reputation on FTE.
The lower hose should be a little cooler, but not cold.
X2 on not using aftermarket thermostats, do a search on here and you will find they did not work most of the time.

Changing the fan clutch is not a hard job at all, and if it is locked up it will cause lower gas mileage.

What is going on that makes you think you have air in the system.
__________________
absolutely no dodges.
to many fords to list.
one town car.sold
If it breaks because of my advice
you can keep both halves
Reply With Quote
  #5 (permalink)  
Old 10-17-2011, 07:19 PM
IDIDieselJohn's Avatar
IDIDieselJohn IDIDieselJohn is offline
Post Fiend
 
Join Date: Feb 2009
Location: Ottawa, Ontario
Posts: 7,789
IDIDieselJohn has a very good reputation on FTE.IDIDieselJohn has a very good reputation on FTE.IDIDieselJohn has a very good reputation on FTE.IDIDieselJohn has a very good reputation on FTE.
Have a read here!

http://www.ford-trucks.com/forums/10...l#post10526448
__________________

1990 Ford F250 4x4, ZF5, L/S 4.10, N/A 7.3L Diesel, 568,808km/377,497 miles, still on the original clutch!
1989 Ford F150 300-6, C6, 2.73, 135,000km/84,000 miles.
1987 Ford E350 26ft. Motorhome, N/A 6.9L Diesel, C6, 3.54, 277,000km/173,000 miles.
1985 Ford E350 Ext Van, 6.9L Diesel, C6, 4.11, 670,000km/419k miles
Reply With Quote
  #6 (permalink)  
Old 10-17-2011, 07:42 PM
josh'sdeisel josh'sdeisel is offline
Senior User
 
Join Date: Dec 2010
Posts: 102
josh'sdeisel is starting off with a positive reputation.
if you live on dirt roads take and power wash the **** out of your radiator because that will condridict on your readings did you put a high temp rtb paste on your thermostat? also if you have air in your ac system that could also contridict it also i think but take and get a vaccume pulled on ;your system and new freeon put in it. maybe flush out your raidiator. drain the over flow and buy the stuff at walmart and run it through your raidiator and follow the directions on the bottle. after that take and put all new fluids and antifreez in it.... heck ya it rainig now on the big red yea gona get out of the drout thank you god you are a great one
Reply With Quote
  #7 (permalink)  
Old 10-17-2011, 10:32 PM
Aune163rd's Avatar
Aune163rd Aune163rd is offline
A Half a meatball....
 
Join Date: Sep 2010
Location: Missoula, Montana
Posts: 4,249
Aune163rd has a very good reputation on FTE.Aune163rd has a very good reputation on FTE.Aune163rd has a very good reputation on FTE.
Well...I hate to 'RAIN' on your parade, but its been raining for 4 days straight up here in MT....
__________________
Quintin Aune BigBs'r #21 & Off. Slackmaster #31
1984 F250 6.9l N/A 212,000 miles Wrecked 26 Oct 11
1990 F-350 7.3l IDI ZF-5(sold)
2000 F-250 6.8l Triton V10 209k miles
2006 F-250 5.4l Triton V8 129k Loaded XL
Reply With Quote
  #8 (permalink)  
Old 10-18-2011, 05:23 AM
cj06's Avatar
cj06 cj06 is offline
Posting Guru
 
Join Date: Feb 2010
Location: CASA GRANDE AZ
Posts: 2,007
cj06 is gaining momentum as a positive member of FTE.
Quote:
Originally Posted by Aune163rd View Post
Well...I hate to 'RAIN' on your parade, but its been raining for 4 days straight up here in MT....

send some rain down my way , AZ , choking on dust ! been a couple of years since a good rain and the garbage is piling up , cant burn it till we get some good rain storms or it will set off a wild fire !
Reply With Quote
  #9 (permalink)  
Old 10-18-2011, 01:38 PM
josh'sdeisel josh'sdeisel is offline
Senior User
 
Join Date: Dec 2010
Posts: 102
josh'sdeisel is starting off with a positive reputation.
well i can only do my best to try and send it over thata way but no promises
Reply With Quote
  #10 (permalink)  
Old 10-18-2011, 04:58 PM
typefour typefour is offline
Elder User
 
Join Date: Aug 2003
Location: Newberg Oregon
Posts: 748
typefour is starting off with a positive reputation.
These engines dont trap air in the cooling system like some foreign POS. Likely the napa stat isnt happy. And if the check ball in the neck is missing it doesnt hurt anything. If stuck it can take longer to bleed the back of the stat.
__________________
91 f 350 cc 4x4, 3:55 gears. zf 5, 7.3 ATS 093 with bigger comp wheel, intercooled with cutdown 7,3 ps IC all gauges ignored with good aftermarket ones. Head studs, balanced . 12 psi 1k pyro under load way better mileage than the 460.

218/461 on the dyno. after 80k miles, wanted to make sure she was broke in.
sandeater1@gmail.com
Reply With Quote
  #11 (permalink)  
Old 10-18-2011, 05:59 PM
giantslayer giantslayer is offline
New User
 
Join Date: Sep 2011
Posts: 11
giantslayer is starting off with a positive reputation.
Thanks,

Should've bought a Ford O.E stat.
Reply With Quote
Old 10-18-2011, 05:59 PM
Reply

Go Back   Ford Truck Enthusiasts Forums > Diesel > Pre-Power Stroke Diesel (7.3L IDI & 6.9L)

Tags
150, 1986, 1989, 1993, 250, 69, 9, change, diesel, f250, ford, hose, radiator, removal, replace, thermostat

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On
Forum Jump



All times are GMT -5. The time now is 01:55 AM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.5.2 ©2010, Crawlability, Inc.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup