New water pump; still leaking

[Bbirge89]

So I've been losing fluid from my radiator at a very high rate and from every angle I could see, the water pump was the most probable source. I replaced the water pump and began to fill my radiator and once the fluid hit thermostat level, I see the leak just as bad as ever. I think the leak is coming from somewhere on the back of the thermostat housing. Once I got the upper thermostat housing out, I could see there would be a problem with the very back 8mm bolt to dismantle the lower portion. I had no clearance for socket or wrench or anything for me to loosen it. I took the cables that ran to my generator off to make more room and took a few hoses off, including the vacuum hose and upper hose to the thermostat. While I still do not know for sure where the leak is coming from, I'd really appreciate any help on how to real the 8mm bolt without possibly a smaller version of my 8mm swivel socket. Any info or help will be very much appreciated. 2005 ford explorer sport trac 4.0L v6 SOHC

 

[swshawaii]

The lower thermostat housing is by far the most common failure on the 4.0 SOHC's cooling system. The lower housing seams are sonically welded, and known to split and leak. I suggest using the single hole RH148 housing and only the DY1004 ECT sensor if you have only one sensor wired. Do not attempt to use the old sensors unless you have replacement o-rings for them, they are guaranteed to leak in the new housing. All the info you need in the link below. GL

http://bengrosser.com/howto/fordthermostat/