Maybe you aren't aware but there have been a lot of mislabeled thermostats on the market lately, from all vendors. Might be a good idea to remove and check the operation of yours before you go doing more and bigger work. Put it in a pot of water on the stove and watch where it opens.

 

I've gone through three of them, so I'm pretty much done trying that.

At any rate, I've got the parts for the inline mod, a new water pump, new fan, and heater backflush parts coming. Still hoping to reuse the radiator; will update after.

 

Inline mod is not always the answer as 180F thermostat is a 180F thermostat. People look to it as the cure all and I just don’t see it like that at all.

 

So you tested three thermostats and proved that they all do open at 180 degrees and you still have these temps... And you know how to bleed correctly... If that is the case your issue is not the thermostat and you don't need the inline mod to solve this issue. Maybe later when you know everything is sorted.

 

I agree that 180 is 180.
I want to do the inline mod so that I can get a cheap, quick change stat at any parts store.
Seems like less hassle, especially since so many seem to be getting 190's that were sold as 180.

 

considering the cost of the stock location t stats this seems like overkill to me. How often do t stats just up and quit working? Not often enough to change everything vs just carry a spare. If on remote trips I still carry enough fluid to refill it from empty and bleeding would still need to happen even if swapping an in line stat. Now buying Abrans kit seems worth the money to me, replace the junction piece and the overflow with nice aluminium pieces is a better use of funds and time imo.

 

I am Slowlyyyyy rebuilding my 4.6(finding time to work on it is the real killer).
So I just want to simplify things when I put the engine back in.
I'm also going to do Best4x4's pyrex tube mod.
That way I can easily see bubbles in the coolant while bleeding, and it'll be easy to spot future coolant problems/head gasket, etc.
I have a completely new coolant system too, including a stock style tank. I wouldn't mind the durability of his aluminum tank either. But, right now, that $200 will go to other things on my D2.

 

I get that; if I wasn't taking the system apart anyway, I'd probably skip it. But from my perspective, the inline mod has a couple things going for it:

1) It's simpler.
2) Having the thermostat on the intake side of the radiator instead of the outlet just seems like a better idea.
3) It appears to be easier to bleed, which I know is a problem.

I'm not going to say the stock setup doesn't work; it clearly does. But a more traditional setup is more within my comfort zone.

At any rate, as soon as I can get it moving again, I'll try and bleed it one more time just to see if that gets temperatures to a level I consider adequate. If it does, great. If not... well, I'll figure that out when I get there.I believe the water pump needs to go anyway; if the thermostat I got from the P.O. is any indication, it hasn't been changed in 215,000 miles.

 

Don't ever assume that I know how to do anything correctly...

I still have a couple things on my list, but the inline is more so I don't have to open up the cooling system multiple times. I've spilled enough antifreeze into the lake behind my house.

 

I got constantly 210F at red lights, now it is around 190F. I found some sludge in my radiator, blocking about 20% of the lower channels (one of the POs probably added green coolant to the red, which is said to produce some gel in the coolant). But this wasn't the only culprit. A new thermostat (180F), a new fan (old one's viscous clutch didn't engage anymore) and extensive flushing brought the temp down, I did all step by step. It brought the temps down step by step, there wasn't a single cure.