thermostat location

[lincsterlv]

Hey there... another new guy to the diesel world. I have a 86' F-250 6.9 diesel, so far it's been great. Read on this forum about changing the heat core (with AC) it was so easy, thanks everyone....now I want to change the thermostat.. so where is the location of the thermostat? Do I have to remove the alternator to change the thermo? Thanks.

[chuckster57]

The factory specified thermostat does not contain an internal bypass. On these engines, an internal bypass is located in the block. The use of any replacement thermostat other than that meeting the manufacturer's specifications will result in engine overheating! Use only thermostats meeting the specifications of Ford part number E5TZ-8575-C or Navistar International part number 1807945-C1.

1. Remove the alternator and vacuum pump belts
2. Remove the alternator.
3. Remove the vacuum pump and bracket.
4. Remove all but the lowest vacuum pump/alternator mounting casting bolt.
5. Loosen the lowest bolt and pivot the casting outboard of the engine.
6. Remove the thermostat housing attaching bolts, bend the hose and lift the housing up and to one side.
7. Remove the thermostat and gasket.
8. Clean the thermostat housing and block surfaces thoroughly.
9. Coat a new gasket with waterproof sealer and position the gasket on the manifold outlet opening.
10. Install the thermostat in the manifold opening with the spring element end downward and the flange positioned in the recess in the manifold.
11. Place the outlet housing into position and install the bolts. Torque the bolts to 20 ft. lbs.
12. Reposition the casting.
13. Install the vacuum pump and bracket.
14. Install the alternator.
15. Adjust the drive belts.
16. Fill and bleed the cooling system.
17. Connect both battery cables.
18. Run the engine and check for leaks.

BTW- WELCOME TO THE DIESELSTOP

[lincsterlv]

Thanks for taking the time to give such a detailed response Chuckster. It's refreshing to have level headed people on a auto forum... so many other forums are really messed up...too many jerks..a-holes..bickering etc.

[chuckster57]

Thank-you, but pretty much all the members here at TDS share the belief that we are here for help and as such, flaming etc... is not to be tolerated. We do have an "off topic" forum that can get lively...take a look sometime.