Weird trans pressures, no reverse, 2-3 bind

PonchoMan

Member
Joined
Jul 5, 2018
Here’s another newby with a fresh 200-4R rebuild with some weird things happening on first start and pressure checks. I rebuilt it myself with mostly new billet parts, I also have the tci manual VB (that requires both accumulator pistons and springs to be removed. The pump got the CK high pressure kit .555 TV .300 reverse boost. The car isn’t on the ground yet so all this is on jack stands with the rear tires removed

Here are the pressures at 700 rpm (made a mistake thought idle was good, I see now 1000 rpm is standard, and tci published values are for 2000)
Park-170-190(high? Maybe still too cool?)
R-150-170
N-140-160
1-120-130
2-110-120
3-110-120
4-110-120
It starts high and as you move through the gears pressure drops. If I rev the engine in gear pressure rises to approx 200 psi.

There’s no reverse, the pressure gauge twitches and pressure changes but the hubs won’t rotate even when I rev it. Hoping it’s something simple.

Second issue is a bind on the 2-3 shift, the hubs stop so I’m assuming it’s a bind. In the CK manual Chris talks about enlarging the #5 3rd accumulator orifice in the separator plate. The TCI VB has its own separator plate and that area of the plate is solid; no holes.

Since I’m double feeding 3rd I think need to drill an orifice in the tci separator plate at this location but not sure.

I ran out of time working on it today so I’ll try again tomorrow and compare pressures for the tci system at 2k rpm, but the reverse and bind are likely not going to be solved by that. Any ideas? Thanks in advance!
 
By the way the TCI VB doesn’t use checkballs. Seems odd, assuming they block passages with plugs. For instance 2 possible culprits for the no reverse issue is check ball 55H and 55E; without them, fluid could exhaust to the lo overrun valve and and the 3-2 control valve both of which I think are removed from the VB. Going to recheck today, maybe pull the van and verify the PR valve train is in correct. Any other thoughts?
 
I have no clue on the manual vb or the constant pressure deal. If it were mine I would swap back to a regular vb as at this point you don't know if it is the vb or is in the transmission. If you can get it shifting and such with the regular vb, then you might try the fancy one again.
 
Looking at the pressures, I would think it is starting in second gear but again it is manual so that might be where it is suppose to be. That .555 boost valve is huge.
 
Looking at the pressures, I would think it is starting in second gear but again it is manual so that might be where it is suppose to be. That .555 boost valve is huge.
Good point about the second gear starts. I pulled the PR valve train from the pump and all of that was proper. I pulled the VB last night and the separator plate looks good, no obvious signs of damage. TCI wants pics of the plate, maybe it was machined wrong? You do have me thinking about the lo/rev clutch, it air checks but maybe the plug/seal isn’t tapped in enough in the case and the circuit is leaking by when lo or reverse are selected. If that’s not it maybe one of the lip seals is cut for the lo Reverse. Still I’m stumped on the crazy high park pressure,100psi over spec.
 
You air checked all the clutches and the servo? Held the air on it to make sure they were sealing?

I'm back to the "high" pressure. Maybe try a .500 boost valve to try to lower it a bit.

I'm kinda spitballin' but with so many changes at once in a trans i'm not sure shifted before you went into it there are a LOT of variables to deal with.
 
You air checked all the clutches and the servo? Held the air on it to make sure they were sealing?

I'm back to the "high" pressure. Maybe try a .500 boost valve to try to lower it a bit.

I'm kinda spitballin' but with so many changes at once in a trans i'm not sure shifted before you went into it there are a LOT of variables to deal with.
Yeah agree. I did air check everything and everything was holding although the lo/rev billet piston has 2 relief orifices that low pressure air leaks from.

I’m hoping the the little lo rev seal that you tap into the bottom just wasn’t installed all the way and it’s leaking by.

I can swap back to the other pressure kit for the pump.

I think I need to drill out the #5 3rd accumulator relief hole in the separator plate to let the band release catch up to the dual fed direct clutch. Here’s a pic showing the Sep plate where the hole should be.
 

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Its NOT the boost valve. You got bigger issues. Crossleaking somewhere and I mean BIG TIME and its not the LR seal plug either. I mean it might be leaking as well but NOT the root of your issues.
No offense but no need to reinvent the wheel. Where is your BRF stuff you took out. ??
Bet if you swapped it back in,, all of your problems go away.
Dual fed and all.
You have a pump halfs issue and/or the VB is junk. My $ is on the latter...
In all the years I have been working on these transmissions , and I think I have done more or at least in the top three of anybody in the world, I have yet to EVER see one of those constant pressure VB s work as advertised , correctly, or at all.
Not to demean …...….. Just a very professional 40 year observation..
WE4
 
Its NOT the boost valve. You got bigger issues. Crossleaking somewhere and I mean BIG TIME and its not the LR seal plug either. I mean it might be leaking as well but NOT the root of your issues.
No offense but no need to reinvent the wheel. Where is your BRF stuff you took out. ??
Bet if you swapped it back in,, all of your problems go away.
Dual fed and all.
You have a pump halfs issue and/or the VB is junk. My $ is on the latter...
In all the years I have been working on these transmissions , and I think I have done more or at least in the top three of anybody in the world, I have yet to EVER see one of those constant pressure VB s work as advertised , correctly, or at all.
Not to demean …...….. Just a very professional 40 year observation..
WE4
Thanks the VB is out and going back through the one that came out and will try again. The TCI VB isn’t set up for dual feeding so the direct clutch was never seeing pressure hence no reverse. I sent it back to them for evaluation might just be asking for a refund and move forward. Hope to have the other VB rebuilt and testing pressures again this weekend. Fingers crossed; thanks for your insight!
 
Here is a worksheet to complete and record your pressures.
Any questions...…….just ask....
WE4

TRANS TEST WORKSHEET.JPG
 
So I rebuilt the VB and got it all installed today; just finished checking pressures and they are still low.
1000RPM idle TV
P-155
R-145
N-145
D-155
3-155
2-155
1-120

1000RPM Max TV
P-180
R-120
N-180
D-130
3-140
2-140
1-120

I do see approx 50 psi increase when I speed the engine up in rev and fwd gears but I still get the impression that it’s very low. I’m about a quart over full. Any ideas?
My gut says it’s the pump. Everything seemed good on the rebuild but I wonder if the rotor to housing tolerance was a little too big if this is what would happen. The converter is a new PI vigilante so I doubt it’s a broken converter hub. What’s your take? Thanks!
 
Thanks the VB is out and going back through the one that came out and will try again. The TCI VB isn’t set up for dual feeding so the direct clutch was never seeing pressure hence no reverse. I sent it back to them for evaluation might just be asking for a refund and move forward. Hope to have the other VB rebuilt and testing pressures again this weekend. Fingers crossed; thanks for your insight!
The valvebody does not dual feed that's inside the unit. If TCI is telling you it in the valvebody run. None of the mass tranny compaines ever figured out the 200-4r like they guys in the TR world did--yup Ol Bruce -- @WE4 is a sharp cat. If he's advising listen and ditch TCI.
 
Yes he is and I am. What I was referring to is the TCI VB and SEP plate is ONLY designed to apply the direct clutch for reverse engagement in the passage we plug (through bolt) when we dual feed. As a result only the lo reverse clutch was seeing pressure in the geartrain when Reverse was selected. When that’s the only one applied no “resersey”. Their VB is set up for a mostly stock trans not one with hydraulic mods. Their VB is an OEM VB with everything gutted except the TV limit and the converter clutch bushing; Their proprietary part is their 3 level aluminum separator plates. That’s all fixed now that I put the original VB back in although I am concerned about the low pressures. There’s a pretty good rise with throttle application and I do have the pump set up with a WOT lockup tube kit fro PI so maybe the lower initial pressures make sense. Not sure.
 
I just don’t get whey the pressures are low even with max TV and then why the Lowest is 1st! I’m thinking pump issue or bad case? Either way it has to come out! Any second opinions?
 
So was the idle pressure with the tv cable connected or disconnected?

This isn’t likely but since this is a retrofit it’s possible the cable adjustment/geometry is keeping the pressure too high at idle. An idle test with the cable unhooked and adjusted loose will tell the absolute minimum pressure the system will produce as assembled. Which is basically all on the PR spring selection. You def have other pump issues though. You SURE the PR valvetrain is correct? Rev boost valve isn’t upside down?
 
All minimum TV values were with the cable unhooked from the carb. I’m pretty confident the PR valve train is right. Wonder if there is crossleaking in the case, just about everything else has been changed. I regret not taking pressure checks before I pulled the trans. I’m wondering if this was the case before.
 
Anything’s possible. I was helping a guy with a problem child via text, he’d bought the trans off craigslist. After sending picture after picture of parts I noticed the tv limit valve was wrong. Someone had inserted the reverse boost valve insert into the tv limit valve. Original valve was long gone. I sent him one. Fixed it.

People do some strange things to cars.

If you take the pump back apart you can post pictures here or text them to me I’ll give you my number. If you post them here you’ll have more eyes looking at the problem though.
 
Anything’s possible. I was helping a guy with a problem child via text, he’d bought the trans off craigslist. After sending picture after picture of parts I noticed the tv limit valve was wrong. Someone had inserted the reverse boost valve insert into the tv limit valve. Original valve was long gone. I sent him one. Fixed it.

People do some strange things to cars.

If you take the pump back apart you can post pictures here or text them to me I’ll give you my number. If you post them here you’ll have more eyes looking at the problem though.
Thanks I’ll do that; I appreciate the help!
 
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