Replacing thermostat assembly expensive

[chrism]

Is there any indication that the older housing allows better access to the end bolt on the intake manifold? If so, that would be reason enough to search one out. The access on our 2003 NA and 2005 T2.5 is a bear!

[F250]

You are correct. Good eye! I had forgotten about that detail. I just confirmed, too that the third mounting bolt hole is NOT in our newer engine blocks.

HOWEVER, given that the mounting face of each housing style is nearly identical, and the newer one is "getting by" with only two of the three potential mounting bolt positions, it seems reasonable to me that the older housing would still mount correctly and seal off as it should without creating a leak potential. On top of that, you can always couple the older housing with a new style gasket, add a thin film of good quality coolant/heat tolerant RTV as an extra measure of insurance, and roll on.

Yet one more way to skin that cat is to thread the third hole and Loctite a short bolt into it as a permanent seal (or use some type of liquid epoxy steel to permanently plug the third hole, like JB Weld).

Like I mentioned earlier (or I think I did), the recommendation to go this route came from a guy who had already done it with no leak or fitment issues at all on his newer engine.

If I were working on an engine which I expected to run for another 60K-80K miles, I would definitely go with the older housing style and then thank myself for that decision the next time I needed to replace the stat.

[fixer333]

Yea I was thinking the same thing , if the bolt spacing is the same. I did not notice you posting about the guy that it worked for , is there anymore info on that? I have called local parts dealers and looked online about the gates TH35991 and no one has it locally ,some foreign sellers on ebay , but they want a lot, plus shipping. I could easily make a gasket for the upper half of the thermostat housing I have now. Its about $80 bucks for the older bare housing , so I don't want to take a chance until I know for sure. I guess a junk yard with some volvos is my next stop. Also need to check the upper hose fitment, to see if the old style hose would mate up to the newer radiator. If it did not , that would be a no go too , because they are shaped hoses.
Thanks, Rob

[fixer333]

Is there any indication that the older housing allows better access to the end bolt on the intake manifold? If so, that would be reason enough to search one out. The access on our 2003 NA and 2005 T2.5 is a bear!

Not sure yet, will get an old one soon and check.

[F250]

Is there any indication that the older housing allows better access to the end bolt on the intake manifold? If so, that would be reason enough to search one out. The access on our 2003 NA and 2005 T2.5 is a bear!

I don't think there is much of anything which will improve access to that particular manifold bolt. However, because of the upward orientation of the old style housing's nozzle, R&R of the upper radiator house is definitely improved!

[fixer333]

I am switching my housing and top cover from the torx screws to bolts. May not make getting to them any easier , but much less likely to strip the heads.