Ahh, saw your picture again. Makes me think I should go that route. This post has been so long and has so much good info that I get confused.
Was it finally determined that "dead heading" it with one valve drove up the head temp too much or is it just a better safe than sorry sort of thing?

 

here are my pics again.

 

The title of this thread should have been "Piston 5&6 Killer Mod." Guys are spending $3-4-500 on kits to tap another port back there to reduce water jacket pressure. Cummins has sold kits to tap ports on the back of the block to add flow back there since not long after the first 6BT was installed in a combine.

Safe, sorry, whatever, they plumbed it like that from the factory for a reason.

 

Agreed, no way I will do it.

 

It's too cold most of the time.

 

I think ill warm it up and hit the road and check the temp. THEN clamp the hose with some smooth jaw vice grips and do the same ride. If there is a difference, do the mod. No difference, do a refill on my 134a.....

 

Mine dropped between 2 and 4 degrees. I did the single valve and after all the reading here I opened it back up for the rest of last summer. I need to do the full bypass so there is no flow issues.

 

My main reason for being interested in this mod was in case my HVAC doors went wild on a hot day. I dont want to "toast" my cyl head but would really like to bypass the heater core. Sigh, whats a guy to do. It was recommended to me by another member who has done this mod that "adding a another coolant line to the number six cylinder and connect to the return side of the heater core for pressure relief" was a good idea. Is that a pre-drilled opening or is that what was talking about.

 

Here's a pic of what it looks like. It's a coolant port plug at the number 6 cylinder.



MikeyB

 

is it possible that the hose coming out of the heater core gets heat exchange with the hose coming out of the head?

 

Do you have another shut off valve that can't be seen on the hose coming out of the heater core before it gets to the tee?

 

Only one shutoff valve. From my testing a shutoff valve isn't needed on the suction side of the core. Didn't see a change in temperature at the vent.

MikeyB

 

Do you happen to remember what was the thread size on the coolant plug?

 

This is from MikeyB (post # 369)

I decided to go ahead and do a coolant bypass for the #6 cylinder. It's cheap and easy to do so why not.

A few parts are needed. Several fittings, hose and hose clamps.

Dorman 56356 5/8" nipple/ 1/2" NPT fitting
Dorman 56387 5/8" Tee fitting (metal)

5/8" heater hose and 4 1.25" hose clamps.

Only problem is the 5/8" metal Tee fitting is hard to find at the autoparts stores and so I ended up ordering it. Everybody has the plastic version but I worried about durability from the heat sitting above the exhaust manifold and turbo.

And from post # 372

Rockauto has the fitting for less than $7. I went ahead and placed a order with them since I needed some stuff for the Magnum.

MikeyB

 

I just used a 3/4" tee from lowes, it is supposed to be for compression crimps but hose clamps work fine since it is fairly tight on there.