I'm pretty sure I've got the Vampire Issue.....

[Gear Report]

Can someone post a pic of the bypass pipe installed?
I bypassed my Tcase cooler this morning and used a section of hydraulic hose for the bypass and another to jump from one tcase cooler nipple to the other.
Not sure why everyone says to use a pipe instead of hydraulic hose for the actual bypass, but I figure I should probably make a bypass pipe just to be safe.
THANKS!

 

[Action]

you can block of the T/C tubes any way you want as long as they are sealed up.....hose, rubber cap, etc.
Hose is just fine on the cooling lines, as long as it isn't kinked.
I have never heard of it being called a bypass pipe.

 

[Gear Report]

I have never heard of it being called a bypass pipe.

Yeah. I made up "bypass pipe".
I saw folks in other posts talk about bending a pipe to install for the bypass.
I made my bypass hose as long as would fit so it has a large radius. Will monitor for any signs that it wants to kink and make a pipe for the bypass if needed.
Tried to ad a picture, but it doesn't give me the option to submit after I pick the image to upload.

 

[MarkM]

I am the latest victim of this but luckily I found the issue before tranny damage was done. Felt a slight slip when cold and I checked the fluid and found she was down three quarts. I bypassed the cooler in the transfer case using a bent up "U" shaped section of 3/8" brake line. Had to replace the air filter and found the only portal to get tranny fluid was the right front. Could have been a lot worse but still a PITA. I did try at first to just use hose (transmission line hose got for 17 bars) but I felt it may kink so I went with the brake line route.

Mark

 

[Gear Report]

I am the latest victim of this but luckily I found the issue before tranny damage was done. Felt a slight slip when cold and I checked the fluid and found she was down three quarts. I bypassed the cooler in the transfer case using a bent up "U" shaped section of 3/8" brake line. Had to replace the air filter and found the only portal to get tranny fluid was the right front. Could have been a lot worse but still a PITA. I did try at first to just use hose (transmission line hose got for 17 bars) but I felt it may kink so I went with the brake line route.

Mark

I hope you are right.
Mine turned out to be a bad pickup tube oring above the transmission filter.

 

[MarkM]

Oh I was as the transfer case was filled to the brim with tranny fluid.

Mark

I hope you are right.
Mine turned out to be a bad pickup tube oring above the transmission filter.

 

[Gear Report]

Same as mine. Turned out to be coming through vent line. Stopped only when I replaced the pickup oring.
Just suggesting that you keep an eye on it to be sure it really was vampire issue.

 

[MarkM]

Yes I will thank you

 

[MarkM]

Well it is good news as the leak was the transfer case cooler and bypassing it fixed the leak. Been driving the truck almost every day and having a blast.

Mark

 

[StackJ]

Read this with a great deal of interest. Does anyone have any photos of the "u-turn"?

Just a note: If I can remember (and sometimes I don't), Turbo400 trannies required a fluid check when in gear. I could be wrong and frequently am.

 

[Dmljohnson]

Ahhh this happen to me...I added a small cheap transmission cooler and mounted it externally, run 2 hose from the transmission line, to the transmission cooler and just make a u on the TC side...

 

[Gear Report]

Ahhh this happen to me...I added a small cheap transmission cooler and mounted it externally, run 2 hose from the transmission line, to the transmission cooler and just make a u on the TC side...

Sorry, I am not clear on what you did.
You added a trans cooler to the trans?
Why?
There is a trans cooler on top of the radiator.

 

[Dmljohnson]

Sorry, I am not clear on what you did.
You added a trans cooler to the trans?
Why?
There is a trans cooler on top of the radiator.

yes I know, I had it at the time, just looks good but serves no purpose, I know the TC used the transmission fluid to cool it, but was looking for a way to loop the transmission lines without kinking it, and I had a small cooler from a shifter cart that fit perfect under there.....lol ....I converted my 86 hmmwv to a 6.6 lml dmax so I don't have that set up any more...

 

[Action]

yes I know, I had it at the time, just looks good but serves no purpose, I know the TC used the transmission fluid to cool it, but was looking for a way to loop the transmission lines without kinking it, and I had a small cooler from a shifter cart that fit perfect under there.....lol ....I converted my 86 hmmwv to a 6.6 lml dmax so I don't have that set up any more...

If you didn't want to kink the hose, all you had to do was put a longer hose on....and you don't even need a hose on the t/c side, just plug (seal) the tubes.

 

[Dmljohnson]

If you didn't want to kink the hose, all you had to do was put a longer hose on....and you don't even need a hose on the t/c side, just plug (seal) the tubes.

So true....I'm one of those over thinkers, you know when something is simple ppl over think it.....it's was months after I realize it didn't make any sense, it made more sense putting it on the TC side with some kind of filter and pump....heres a pic of my 86 hmmwv with civilian doors...

 

[319cssb]

So do the NP 242 have this leak in the TC case cooler line happening less frequently? I am fairly sure , that I have a NP 242. It looks like what I can google up and I found a NP 218 earlier in this thread and what you can see doesn't look like mine. Also on my TC is some sensor or solenoid on the backside between fill and drain, which is not hooked up to anything. I think My TC has been replaced.

 

[86humv]

So do the NP 242 have this leak in the TC case cooler line happening less frequently? I am fairly sure , that I have a NP 242. It looks like what I can google up and I found a NP 218 earlier in this thread and what you can see doesn't look like mine. Also on my TC is some sensor or solenoid on the backside between fill and drain, which is not hooked up to anything. I think My TC has been replaced.

You have a 242....there's an early and late one...early has a 3 bolt tail shaft housing, late has 4 bolts.
There is a round I.D.plate facing aft that says what it is, and should have a date.
The updated ones sometimes had a blue band around one of the cooling tubes just outside the T/C.

 

[Retiredwarhorses]

The 242 had the vampire issue...the blue band on the inlet and outlet tube are the new type and fixed the issue.
your wire is your Tcase lock lamp switch...you need the name and harness to make it work.

 

[319cssb]

double post... ready to delete!

 

[319cssb]

I wasn't looking forward to checking the transfer case level today.
But it looks ok.

So I'm pretty sure now, that I have a NP 242

...the blue band on the inlet and outlet tube are the new type and fixed the issue.
...

Is this the blue band you talked about?