E4oD check valve

[OLDBULL8]

Any one that runs an automatic trans. should have a temp sensor. The bypass fitting still has the regular flow from the aux cooler, but if it becomes plugged for any reason the flow then reverts back thru the bypass fitting, thence you have lube to the rear bearings. If plugging happens, the trans will fluid will heat up due to no cooling, maybe to the point of overheating, hence the need for a sensor.

 

[2stroke]

Ok If I understand with this kit installed there will be 2 check valves one in the Trans cooler circuit and the other in the bypass circuit.
The bypass has a larger section near the fluid return from the cooler for one of the check valves and the other one is in the cooler feed line fitting, it doesn't show in the diagram?
Please comment.

 

[OLDBULL8]

The original check valve in the transmission acts like it always has. the check valve in the bypass fitting keeps the fluid flowing to the cooler. In the event the cooler and/or line to it plugs up, the back pressure from plugging will open the check valve in the bypass fitting so fluid flows back into the transmission thru the original check valve in the transmission to lube the bearings. Furcista, Spanish for, do you understand now.

 

[trackspeeder]

Ok If I understand with this kit installed there will be 2 check valves one in the Trans cooler circuit and the other in the bypass circuit.
The bypass has a larger section near the fluid return from the cooler for one of the check valves and the other one is in the cooler feed line fitting, it doesn't show in the diagram?
Please comment.

What you see is a basic ATSG line drawing. ATSG doesn't go into heavy details, its a basic rebuild manual.

 

[2stroke]

I was just making sure there were two check valves so as not to assume so, perhaps oldbull8 should think some of us may not be highly knowlegable as he is. (no sarcastic comment here)

 

[2stroke]

I had an additional thought or maybe comment that the bypass check valve, I hope has a higher opening pressure so fluid favors the cooler first. perhaps Trackspeeder can add to this.

 

[OLDBULL8]

YES No comment.

 

[trackspeeder]

I had an additional thought or maybe comment that the bypass check valve, I hope has a higher opening pressure so fluid favors the cooler first. perhaps Trackspeeder can add to this.

Yes, the bypass requires a much higher pressure to open. If it didn't hot fluid would go through the bypass and never make it to the cooler. That would get ugly very quickly.

 

[2stroke]

I am going to get this bypass kit and will post a follow up.

 

[nostrokes]

For 3/8" lines just buy a 4R100 bypass set up. No drilling or other fiddling required. You can find them at a Ford dealer or junk yard. If you buy used it can be rebuilt cheaply with a Sonnax kit.

Do not remove the check valve. You will damage the tranny.

OK guys I know this is a old thread but..... I bought the bypass after hours of searching and getting the "correct" part numbers, bypass (2c3z-7h322-ba supersedes all other part numbers) 99 up cooler lines ect... Feeling very confident that I had found exactly what I needed, I started putting things back together, new flex plate in, tanny and t-case with cross member installed and bolted up and low and behold the rear fitting doesn't fit. The bypass fitting threads are larger than the original threads for the return in the rear. The supply side is fine fit perfect, and the rear lines up just right, but no go on the fitting. Is there something I am missing? There is no other fitting besides the 5/16 line adapter that was installed there that can be taken out, no one ever mentioned if this works on the older trucks or if they had to do any mods. I am really set on doing the 3/8 conversion and would really like to put the bypass in because the cooler I bought doesn't have a bypass, and I need this truck to last for another 5 years or so hopefully longer (truck is paid for that's how I'm justifying this cost to the wife). I did find a part number for the e4od bypass f75z-7h322-ab, but it looks like it still has the 5/16 line fittings?? I want to do the 3/8 because my new radiator and aux cooler both have 3/8 fittings and it will flow better with it. Planning on sending the bypass (and lower dipstick tube, these are on my e4od casting number post) back tomorrow unless someone has a solution....


Thanks all in advance... Good thing I don't have hair on my head or it would be gone and bloody by now...

 

[trackspeeder]

Did you remove the check valve? When installing the bypass, the check valve gets tossed.

 

[nostrokes]

Did you remove the check valve? When installing the bypass, the check valve gets tossed.

As far as I can tell yes. I removed both the front and rear line adapters all that was left was the transmission housing.

 

[nostrokes]

Here's a couple pics. Pulled the rear fitting again this morning just to be sure, and it's not even a check ball so guess I'll be on the hunt for one that will accept the 3/8" inverted flair.

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Pay no mind to the white plastic piece. Jammed it into the nut to stop the leak.

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Fitting removed...

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Side by side comparison. Hard to tell from the pics but the bypass fitting threads are larger the shiny ring on the front of the bypass fitting is where it was rubbing on the case or threads when I tried to install it.

I'm not doubting anyone's knowledge or experience, I just want you to see what I'm seeing, so please don't think I'm knocking anyone here.

Is it possibly that there was a modification on the trans housing after the production year of this one? I sent BTS an email asking for Brian's input also, figured it couldn't hurt seeing how he works on these all the time.

Zf swap is rrrreeeeaaaalllllyyyy starting to sound good right about now....

 

[nostrokes]

So here's the thought process now.. There is a supply company here that has/can get just about every fitting known to man. Buy a 9/16-18 nps-orb to 3/8 tube inverted flare, 3/8 in line compression or barb fitting with a check valve, and find a bypass that I can put in line. If its barb fittings I would put it near the aux cooler on the return side. I have seen a 5/16 compression fitting with a check valve, that's what gave me the idea..

Any of you transmission gurus think that's a bad idea? What opening pressure should the valve be 2psi-10psi??