Cooling System Conundrum

[unclehoser]

What started out to be a water pump replacement ended up being a replacement of everything in the cooling system but the block. That went fairly smoothly, considering the age of the vehicle.

Here's the fun part: While under the hood, I noticed that someone along the line had added a couple of "T" fittings in the heater hoses, inflow and outflow, with a hose between them. This makes absolutely NO sense. It's not like they were bypassing the heater core, but cutting the flow by half or so by introducing another water path "in parallel", if you will.

Granted, in the Arizona desert it doesn't get that cold, but there are mornings where it will dip into the 30's and I was wondering why it took so long for the truck to get warm in the cab! I think I now know.

Why the hell would anyone make a modification like this? Should I put it back to stock condition, or is there some kind of reasoning behind it? My brain itches from scratching my head..........

 

[madpogue]

No valves? All I can think of is that they started down the path of doing a bypass, but never finished the project.

 

[unclehoser]

That was my thought. Bypass in summer, use in winter, which makes sense. The truck came from Phoenix, and I'm 200 miles west of there where it's even hotter! So far, though, I haven't had any cooling issues in summer (except for the aforementioned water pump leak from hell!).

I might just put a valve in there...couldn't hurt!

 

[chris142]

The blend door is not closing or sealing all tbe way. Allows hot air to mix with the cold air. Cutting off the hot water makes the ac blow cold again.

 

[clint bartels]

The only thought that hasn't been said already. Someone tried to put a 6.0l coolant filter in a 7.3l.

 

[unclehoser]

The blend door is not closing or sealing all tbe way. Allows hot air to mix with the cold air. Cutting off the hot water makes the ac blow cold again.

That could make some sense, but why not bypass the heater core completely, rather than just halfway? So far, I haven't noticed any problems with cooling in the summer (and, believe me, it's HOT here! 120 is NORMAL!).

The best way I can explain it is that the heated water hasn't been shut off completely; rather, it has been re-routed both through and around the heater core. The routing looks like an "H", with the top of the "H" being the inlet/outlet hoses to the heater, the bottom of the "H" being the inlet/outlet hoses to the cooling system, and a 'crossover' hose in between, where the "H" has a horizontal line! It makes no sense to me at all.

It's a bit rough to explain without a picture or diagram, but I hope you'll get my drift!

Much appreciation for the input, and PLEASE post more ideas and explanation if possible. I'm not a mechanic by any means, and I need good advice!

 

[unclehoser]

The only thought that hasn't been said already. Someone tried to put a 6.0l coolant filter in a 7.3l.

As far as I can tell, there is no coolant filter installed on this engine...unless it's somewhere I haven't seen yet!

I just finished replacing every element of the cooling system I could identify, and only noticed this particular modification while installing a flush/fill "T" in a heater hose. I'm confused...but that's normal!

 

[unclehoser]

No valves? All I can think of is that they started down the path of doing a bypass, but never finished the project.

I'm thinking you may be right...or, possibly, that someone was more confused than myself!

 

[clint bartels]

Any chance of pictures?

 

[unclehoser]

Any chance of pictures?

One of these days, I'll find time to figure out how to post pics...Photobucket has gone totally commercial, and everything I had there is null and void. The 2 pics of my truck in the sig are non-existent due to their silliness..
Hang in there...it's all a matter of having the spare time to set up another hosting account somewhere.

 

[madpogue]

Upload 'em to your account gallery here on OBN and then link it to the post. Then it's all "in the family", not dependent on some other hosting site that may change their rules in the future (when would that ever happen?....).

 

[unclehoser]

Upload 'em to your account gallery here on OBN and then link it to the post. Then it's all "in the family", not dependent on some other hosting site that may change their rules in the future (when would that ever happen?....).

Didn't even know that was possible! I'll give it a shot...thanks!