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Discussion Starter · #1 ·
Years ago i did the radiator bypass - and never really gave it another thought. But, the time has come that I have had to replace the radiator - and would like to hook the tranny lines back up the original way.

I did the version of the bypass where the long hose on driver's side of radiator is plugged into the left side of the radiator creating a "closed loop". I don't remember that much fluid running out of the radiator when i did the bypass. That said, are there any precautions I should take in "undoing" the bypass? (Long hose back to tranny line. Short hose back to passenger's side of radiator). Being it is a new radiator there isn't any tranny fluid in it - and I have no idea how much to fill the tranny to compensate.

Any guidance here?
THX!
 

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Years ago i did the radiator bypass - and never really gave it another thought. But, the time has come that I have had to replace the radiator - and would like to hook the tranny lines back up the original way.

I did the version of the bypass where the long hose on driver's side of radiator is plugged into the left side of the radiator creating a "closed loop". I don't remember that much fluid running out of the radiator when i did the bypass. That said, are there any precautions I should take in "undoing" the bypass? (Long hose back to tranny line. Short hose back to passenger's side of radiator). Being it is a new radiator there isn't any tranny fluid in it - and I have no idea how much to fill the tranny to compensate.

Any guidance here?
THX!
Nextown,

I would get everything hooked back up like it is supposed to be.

Then start with a Cold Engine and let it warm up to operateing temperature by watching the Coolant Gauge. Then Check the ATF Level useing the Cold Range by useing the method Exactly as shown in the Nissan Service Manual. I would get the level 1/2 way between the Low mark and Full Mark.

You really need something that will tell you the ATF Temperature when checking the Fluid, especially in the Hot Range. In cold weather it take's forever to get mine up to 149F Degree's to check it in the Hot Range, so I usually do that in the Summer time. Even in the Summer Time it take's a long time as well, maybe cause my rear end is a 2.937 ratio.

I use a Scangauge II to monitor the ATF Temperature's in my '13, but i'm not sure that a Scangauge II will work for your year. You'll have to check with Scangauge to make sure on that.

Regards,
 

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Looks like the xgauge stuff only goes back to 2008. just my luck!
Netxtown,

I thought I read that somewhere, but if you haven't checked with linear Logic/Scangauge, I would just in case they now have the code's to update that will.

I still think you'll be ok useing the Cold Range like I described above, and use the Coolant Gauge in the Dash Cluster. When the Engine Coolant reach's the normal operateing temp, then follow the procedure in the Nissan Frontier Maintenance Manual to the letter and put the level 1/2 way between the Low and Full Mark's in the Cold Range, until you get a device to show the exact ATF Temperature. On my '13 there is a Temperature Sensor in the ATF Sump and another one @ or Near the Torque Converter. It's the Sensor in the ATF Sump that give's the Temp for the ATF Fluid Level Check.

Regards,
 

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Discussion Starter · #5 · (Edited)
And just when you thought you were on the home stretch.....

Crawled under to undo the bypass. Seems the friendly mechanic who installed the radiator - couldn't figure out the bypass stuff.....so he switched the hoses to utilize just the radiator. And in doing so - he disconnected the longer hose from the external cooler - and tossed it in the trash. Well, exit stage left! (that was the polite way of saying G$#@($#%^#@$%#@[email protected]# !

If I remember reading it here....that hosing is 5/16" ID ??? Yes ???

And, now that both hoses from the ext cooler have been removed...not only do I NOT have the hose....but I don't remember what goes where. The mechanic took the "shaped" hose and connected it to the right side tranny line, with the long hose from the left side radiator tranny port connecting to the left side tranny line. As for the ext cooler, coming off the tranny cooler there is one line mounted that has its connection fitting setting horizontal, while the other line is just kind of dangling down with an in-line connector inserted into it.

I am thinking the shaped hose goes up to the horizontal fitting on the ext cooler, and the hose that attaches to the in-line connector fitting goes down and connects to the right side tranny line. This would set the flow going to the external cooler first, then to the radiator, then back to the transmission. ( I may have the actual flow direction backwards - but the connections would still be the same....or at least I hope!)

Can anyone verify if this is correct? So far I have found no pics showing the actual connections for the ext cooler..
 

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Discussion Starter · #6 ·
Netxtown,

I thought I read that somewhere, but if you haven't checked with linear Logic/Scangauge, I would just in case they now have the code's to update that will.

I still think you'll be ok useing the Cold Range like I described above, and use the Coolant Gauge in the Dash Cluster. When the Engine Coolant reach's the normal operateing temp, then follow the procedure in the Nissan Frontier Maintenance Manual to the letter and put the level 1/2 way between the Low and Full Mark's in the Cold Range, until you get a device to show the exact ATF Temperature. On my '13 there is a Temperature Sensor in the ATF Sump and another one @ or Near the Torque Converter. It's the Sensor in the ATF Sump that give's the Temp for the ATF Fluid Level Check.

Regards,
Sounds good - but i have to get it running again. Threw P0021 on way home from mechanic's shop. Could be left side vvt....or could be timing chain has jumped. It all runs fine from a cold start - but as soon as it warms up and RPM drop to <700, the rough idle starts. I also noticed a clackety sound a split second after starting.

I know I am getting tired of chasing one thing after another......
 

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Discussion Starter · #7 ·
And thank you to all who blew on past this post.

I am still trying to figure out what hose goes where, and all of the video's and diagrams don't show crap when it comes to ALL of the hosing involved.

I get it that the hose from the driver's side goes directly to the tranny line. And that is pretty much where it all ends. The molded hose from the passenger's side should route up to the tranny cooler - but to which connection? The one hanging down with an in-line connect, or the connect that is mounted horizontally? I'm don't know which piece of hose i am missing as the dumbass mechanic who replaced the radiator tossed it. Is it another molded hose of some sort?

I need some help here, guys.
 

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Discussion Starter · #8 ·
So ... i said "F" it!....and just put it back together in what may or may not be the original configuration. I really don't care which way the crap is flowing.

Thanks for all the great help!
 

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And thank you to all who blew on past this post.

I am still trying to figure out what hose goes where, and all of the video's and diagrams don't show crap when it comes to ALL of the hosing involved.

I get it that the hose from the driver's side goes directly to the tranny line. And that is pretty much where it all ends. The molded hose from the passenger's side should route up to the tranny cooler - but to which connection? The one hanging down with an in-line connect, or the connect that is mounted horizontally? I'm don't know which piece of hose i am missing as the dumbass mechanic who replaced the radiator tossed it. Is it another molded hose of some sort?

I need some help here, guys.
Nextown,

I've never done the Radiator ATF Cooler bypass, but there are severl writeup's on the WWW by those that have.

You might find one with a picture that will help on the WWW.

Good Luck,
 

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Discussion Starter · #10 ·
I undid it by myself using guestimate and "looks like this fits" logic.

FWIW - all the WWW pics do not show the cooler hoses. Only the hoses where they connect to the tranny lines or just the radiator. Nothing that identifies the two lines on the cooler.
 

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Discussion Starter · #11 ·
And for this thread closing statement......

IF you did the BYPASS - GET a new radiator and GET the bypass undone. With normal everyday driving you are slowly baking the crap out of the engine - AND every thing attached to it via gasket or o-ring.

There should have been a large "warning! warning! warning!" on the original info to do the bypass. Leaving the bypass in place WILL cost you an engine or a tranny - sooner or later.
 
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