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Beyond the Sea
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Discussion Starter #1
I need help on this one bad: My buddy has a BOT 2004R tranny (only a 2000 miles on it). We've had problems with it from the start, but the folks at BOT have been very patient with us, trying to walk us through repairs to get it working properly. They've also sent us quite a few parts to do it, as we live in Germany. It's simply too expensive to send the trany back to California.

Right now the trany will shift normally when it is cold. Once it is fully warmed up you can't give it more than about 1/4 throttle, otherwise the pressure will get stuck high (we have a guage attatched at the pressure port on the trany, supplied by BOT). This causes very late and harsh shifting. This condition will persist until the the car has been shut off for an hour or more. On restarting the car will shift normally, until it warms up and you give it more than 1/4 throttle.

BOT recently sent us a replacement valve body, which we installed carefully, following instructions in the manual and using a torque wrench (my friend is a licenced mechanic). BOT does not have any idea what could cause this, and neither do we. ANY HELP MUCH APPRECIATED!!!!!!!!!
 

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Berliner Bel Air said:
I need help on this one bad: My buddy has a BOT 2004R tranny (only a 2000 miles on it). We've had problems with it from the start, but the folks at BOT have been very patient with us, trying to walk us through repairs to get it working properly. They've also sent us quite a few parts to do it, as we live in Germany. It's simply too expensive to send the trany back to California.

Right now the trany will shift normally when it is cold. Once it is fully warmed up you can't give it more than about 1/4 throttle, otherwise the pressure will get stuck high (we have a guage attatched at the pressure port on the trany, supplied by BOT). This causes very late and harsh shifting. This condition will persist until the the car has been shut off for an hour or more. On restarting the car will shift normally, until it warms up and you give it more than 1/4 throttle.

BOT recently sent us a replacement valve body, which we installed carefully, following instructions in the manual and using a torque wrench (my friend is a licenced mechanic). BOT does not have any idea what could cause this, and neither do we. ANY HELP MUCH APPRECIATED!!!!!!!!!
First thought is the TV bore & valve are worn out. Fluid can blow by the valve and put the trans into a false high throttle mode

I am not familar with BOT ......... What company is that?

:cool:
 

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I think he means BTO (BowTie Overdrives)
Wouldn't the valve body change have made a change in the valve you mentioned?
JA
 

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If the TV balance hole cannot exhaust TV boost oil the TV valve will become hydraulicaly locked at max TV causing overboosted condition. This problem is more common hot than cold.

Now that you have an idea of the problem....how to fix?? Drill the TV balance hole slightly larger. I just don't remember the correct size :spank: :spank:
I will get info (posssibly a pic too) and post later....
 

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Chazmac said:
If the TV balance hole cannot exhaust TV boost oil the TV valve will become hydraulicaly locked at max TV causing overboosted condition. This problem is more common hot than cold.

Now that you have an idea of the problem....how to fix?? Drill the TV balance hole slightly larger. I just don't remember the correct size :spank: :spank:
I will get info (posssibly a pic too) and post later....

I open them to .055 hole. I have seen bores worn badly enough the .055 hole and a Transgo valve did not fix the problem ( 700r4 tranny). I had to bore the hole out and install an over sized valve which cured the problem.


I think he means BTO (BowTie Overdrives)
Wouldn't the valve body change have made a change in the valve you mentioned?
JA
Not if both valve bores are worn out.......

Mayb he means Burbank Overdrive Transmissions ?

:cool:
 

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Crosley is correct,
the TV valve can stick causing the symptoms.

The TransGo SK 200-4R has a small spring that helps return the TV valve, a governor spring from an FMX will also work if you can find one over there.

I've also had issue with the TV boost valve getting stuck on poorly machined aftermarket parts.
 

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jakeshoe said:
Crosley is correct,
the TV valve can stick causing the symptoms.

The TransGo SK 200-4R has a small spring that helps return the TV valve, a governor spring from an FMX will also work if you can find one over there.

I've also had issue with the TV boost valve getting stuck on poorly machined aftermarket parts.
I think all of the posted suggestions are in the area that needs to be addressed. If the trans is from Bowtie Overdrive tranny not the Burbank overdrive tranny shop..... Bowtie has a good customer service reputation.

in this case there is a large pond of water in the way :D
 

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Beyond the Sea
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Discussion Starter #8
Hi everyone, thanks for the advice so far,

I meant BTO, Bowtie Overdrives. They sent me the replacement valve body (outside of the warranty period, to their credit), so I don't think that the TV valve or anything in the valve body could be the problem, given the exact same symptom with two different valve bodies.

Could the oil pump cause this problem? Or something else?
 

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I wouldn't rule out the TV assembly even with a different valve body. This is a common problem and is the reason TransGo has a kit that specifically addresses this problem on the 200 and 700's.

I would recommend getting the Transgo SK and installing the TV valve spring and the metal tag, ensure the TV valve is smooth with no burrs, and will shuttle back and forth smoothly when it is assembled.

The pressure regulator and TV boost valve assemblies are in the pump, you can remove them with the pan off and ensure the boost valve isn't sticking but this doesn't sound like the issue.

Just so you know,
Crosley and chazmac are both very knowledgeable builders (who do it for a living) so I would listen to their advice.

Good luck with it.
 

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Beyond the Sea
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Discussion Starter #11
When its started cold the pressure guage shows 90 psi. Once it gets stuck in the high pressure mode the guage shows 150-180 psi all the time, in every gear and at idle in neutral too. The guage and pressure hose vibrate/pulse strongly too, causing the indication to vibrate between 150 and 180 psi.

We pulled the trany out again and took out the oil pump. We put the 10 vane pump part into a spare oil pump from another (old) 2004R we have and reinstalled it. However, the same problem remained.

We appreciate the advice from the experts so far, its just a little hard to imagine that we got two bad TV valves in 2 valve bodies from a professional rebuilder (bowtie overdrives). On the other hand if the problem is not in the pump or the valve body, is there even a theoretical possibility that anything else could cause our problem?

thanks again
 

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2004R shifts too high when hot! expert needed!!

OK Berliner,usually 90 psi in park would raise a red flag,but Bow Tie calibrates their units to run high line.

At 150 to 180 psi,when warm,this could be a pump problem or a tv problem.

When hot and gauge shows 180psi,if you rev the engine up and the gauge goes up a little,5-10 LBs,this would indicate the pump is working like it should,the pressure regulator is not sticking,pump slide is not sticking,etc.

Then you would suspect the tv sticking,as suggested by the other very well qualified trans guys.

Now if this were me,and the gauge points to a tv problem[I know,2 different vb],but if I thought it was tv, I would pull the pan,pull the roll pin that retains the tv plunger,then pull the plunger out of the vb.

Lay it in the pan or put it in your pocket,if you like,but get it out of the vb.

This will drain the tv system. Now with the plunger out,start it up and get it hot[WITH THE GAUGE ON IT].

Check your pressure,fast way to pinpoint concern. Good luck,please post back with your results.
 

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valve body kits
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Chazmac said:
If the TV balance hole cannot exhaust TV boost oil the TV valve will become hydraulicaly locked at max TV causing overboosted condition. This problem is more common hot than cold.

Now that you have an idea of the problem....how to fix?? Drill the TV balance hole slightly larger. I just don't remember the correct size :spank: :spank:
I will get info (posssibly a pic too) and post later....
-----------------

.055" - .0625" is a reasonable range.
PIC is not necessary. the hole is in the plate directly over the small end of the throttle valve, opposite end from plunger. its about .031 factory.
 

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Beyond the Sea
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Discussion Starter #14 (Edited)
We're going to drill the valve body spacer plate hole as suggested. Will post results after its back together again, in a few days. Many thanks for the ideas so far, without your ideas we would have just pulled it and turned it into an oversized paper weight...

Will post as soon as its back together again and test driven...

Incidentally, all BTO 2004Rs have the Transgo Shift Kit installed in them.
 

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Beyond the Sea
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Discussion Starter #15
Ok, it's back together. We drilled the bleed hole a little more than you guys recommended, to 2mm (that's 0.079 for you). Hope that's OK. We didn't have the right size drill handy.

However, it made no difference to the operation. It shifts fine off the start until you give it more than about 1/4 power. Then it gets stuck in a high pressure mode, that is it shifts very late and harsh. If we shut the engine off for 10 seconds or more it will perform normally again. Shifting the gears back and forth between O or D and R doesn't help. Only shutting it off for 10 seconds or more does.

What should we do now? Should we pull the TV valve as described earlier? If we do that what should we see? Does too high pressure (above 100 psi) mean the oil pump is the problem? And if the pressure stays at 90 psi then the problem is in this (and the previous) valve body? I guess the test can only be done while in Park, surely one cannot drive without the TV?
 

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2004r Shifts Too High When Hot! Experts Needed!

Berliner,maybe we should start from scratch.

Since the car is back together,I suggest putting the gauge back on it first.

Go back and reread post # 12. We need to see if the pump is responding as it should.

You will not need to drive it with the gauge on it,get it hot enough for the pressure to go over 150psi,then let's see what the gauge does.

Record everything you see,then post back.

Also if the pump slide sticks,this trans can jack pressure up to over 300psi,so watch that gauge carefully. Also .079 is too large a hole for tv balance. This can be closed down with a steel ball and a hammer.
 

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Beyond the Sea
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Discussion Starter #17
It's been a while since I last posted on this problem. Here's the update:

Bowtie Overdrives was kind enough to send us a new oil pump (again out of warranty). My buddy installed it this past weekend. But it made no difference at all :pain:

So now what? New valve body, new pump, same old problem. What would testing the TV valve like in post #12 tell us? We've already replaced both the pump and the valve body, and my buddy (and to a degree me as well) fails to see the point of the test. Next question is, what impact would the slightly oversize drain hole have, is it really necessary to reduce it?

I really respect your opinions and advice, I just need some good arguments with which I can motivate my nearly suicidal friend to continue on trying to fix this POS tranny (the folks at Bowtie have been very patient and supportive, but our problems have been going on for over a year, not just this current problem either, we're at our wits end).

Could any other problems cause these symptoms? Some sticking clutches or something of that nature?

thanks again
 

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200 4r

I would install complete different trans in your case you've tried every thing short of it.The problem might be a cross leak between valve body and case. I understand shipping cost trouble but when you add all things you've tried that adds up too, your time, trouble, pan gaskets and fluids. Where do you say enough is enough???? The core is still available and they should understand your frustration, I would ask them for another unit and offer the shipping cost.
I want to go out on a limb here did you try to change the governor and housing, I don't see the correlation to high line pressure but when you reaching for answer's. also you might try 3/8 plastic balls in the bath tub's over the years I had many weird problems and found other people suggestion's have worked for me.
 

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Beyond the Sea
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Discussion Starter #19
We replaced the oil pump with a new one and it made no difference. We had a BOP 2004R lying around so we made one absolute last attempt at repair (about the tenth time in 6 months). Layed them both out side by side, selected the best looking components from each and put them all into the Bowtie housing. AND IT WORKED!! :thumbup: :thumbup: Better than ever even.
Thanks for the advice, but we never really found out what was wrong with it...
 

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2004R shifts too high when hot!

That's great!! You know, sometimes it's better to be lucky, than good.

Thanks for posting back with your good news!
 
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