A999 First gear engagement

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Jax

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I have a fully build A999 trans, we just have made about 15 passes on it. Sometimes when I shift into 1st gear the engagement of the trans does not take place right away. I rev the engine, and like after a second or so the car start moving.

I have verified the oil and the trans is full, I thought probably it was low on trans fluid and took time to engage.

What can be the cause of of delaying the engagement into 1st gear?
 
Check fluid level idling in neutral. Always been this way? Hot or cold? Low 1 and D? Worn forward clutch..excessive clearance.
 
Check fluid level idling in neutral. Always been this way? Hot or cold? Low 1 and D? Worn forward clutch..excessive clearance.
No it wasn't always like that it start doing that like after 10 passes. Yes in low 1. It is a fully build manual transmission.
Sometimes it engages right away sometimes not.
And yes we have check the oil level but not in neutral but in park with the engine running cold.
 
They usually say "Check when hot idling in neutral" on the stick. Torqueflites won't charge the converter in Park. Burnt forward clutch. Easy fix; just pop out the front drums is all. If the fluid is still bright red and there's nothing in the pan, you might be alright.
 
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They usually say "Check when hot idling in neutral" on the stick. Torqueflites won't charge the converter in Park. Burnt forward clutch. Easy fix; just pop out the front drums is all.

Thanks for the feedback. Will let you know
 
L/R servo might be leaking, or worse cracked;
assuming you have tightened up the band,lol.
No I haven't made any adjustment what so ever after we start using the transmission.
 
Well then , a band adjustment would be first on my list of to-dos, and an inspection of the L/R servo at the same time.
What is the procedure to adjust the band?
 
To adjust the L/R band the pan has to come off. There is a procedure for adjusting it that I do not have documentation for.
But I can tell you how I do it.
I find the adjuster, back off the lock nut, and with a really small,short wrench, I just run the adjuster in until snug. Then I back it off until there is about 1/4 inch motion of the apply-arm, and lock her down with the nut. That band will run with more clearance and with less. If there is too much clearance, you might have a delayed engagement. If there is less it might really BAM! going into gear. Also with less clearance, the 1-2 shift-overlap may become an issue. Overlap causes the nose to drop during the shift, because some of the engines power is being used to fight the shift; the trans effectively being in two gears at once, with second applying and first releasing.
I have found the 1/4 inch spec to work well for me without respect for what car the trans is in, and it's easy to remember.
The pin you are clearancing, is part of the Low/Reverse servo assembly. The pin is steel, but the body it is installed into is aluminum. That part is a known weak part when the pressures have been tweaked for racing or high-performance. They crack, split and/or turn sideways. So check yours while you are in there. I don't think you can get it out of the bore without removing the band anchor-pin. But the crack/split should be obvious if it exists. Yours won't have rolled cuz then you lose reverse completely. And yes I have seen pictures of the lip seals blown, but have not personally seen it, although I haven't built that many myself either, perhaps two dozen.
 
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To adjust the L/R band the pan has to come off. There is a procedure for adjusting it that I do not have documentation for.
But I can tell you how I do it.
I find the adjuster, back off the lock nut, and with a really small,short wrench, I just run the adjuster in until snug. Then I back it off until there is about 1/4 inch motion of the apply-arm, and lock her down with the nut. That band will run with more clearance and with less. If there is too much clearance, you might have a delayed engagement. If there is less it might really BAM! going into gear. Also with less clearance, the 1-2 shift-overlap may become an issue. Overlap causes the nose to drop during the shift, because some of the engines power is being used to fight the shift.
I have found the 1/4 inch spec to work well for me without respect for what car the trans is in, and it's easy to remember.
The pin you are clearancing, is part of the Low/Reverse servo assembly. The pin is steel, but the body it is installed into is aluminum. That part is a known weak part when the pressures have been tweaked for racing or high-performance. They crack, split and/or turn sideways. So check yours while you are in there. I don't think you can get it out of the bore without removing the band anchor-pin. But the crack/split should be obvious if it exists. Yours won't have rolled cuz then you lose reverse completely. And yes I have seen pictures of the lip seals blown, but have not personally seen it, although I haven't built that many myself either, perhaps two dozen.
Thank you.. great info. Will use it if the problem persist
 
To adjust the L/R band the pan has to come off. There is a procedure for adjusting it that I do not have documentation for.
But I can tell you how I do it.
I find the adjuster, back off the lock nut, and with a really small,short wrench, I just run the adjuster in until snug. Then I back it off until there is about 1/4 inch motion of the apply-arm, and lock her down with the nut. That band will run with more clearance and with less. If there is too much clearance, you might have a delayed engagement. If there is less it might really BAM! going into gear. Also with less clearance, the 1-2 shift-overlap may become an issue. Overlap causes the nose to drop during the shift, because some of the engines power is being used to fight the shift; the trans effectively being in two gears at once, with second applying and first releasing.
I have found the 1/4 inch spec to work well for me without respect for what car the trans is in, and it's easy to remember.
The pin you are clearancing, is part of the Low/Reverse servo assembly. The pin is steel, but the body it is installed into is aluminum. That part is a known weak part when the pressures have been tweaked for racing or high-performance. They crack, split and/or turn sideways. So check yours while you are in there. I don't think you can get it out of the bore without removing the band anchor-pin. But the crack/split should be obvious if it exists. Yours won't have rolled cuz then you lose reverse completely. And yes I have seen pictures of the lip seals blown, but have not personally seen it, although I haven't built that many myself either, perhaps two dozen.
I missed something here. Why would there be band overlap from 1-2
 
In manual low the low reverse band is applied to give engine braking in first gear. Then it has to release at the same instant the second gear applies. But you probably already knew the second part.
 
In manual low the low reverse band is applied to give engine braking in first gear. Then it has to release at the same instant the second gear applies. But you probably already knew the second part.
Well I have retread the post and it sounds like this is a drag car with manual shift. No mention of brand of valve body or transbrake so we do not know if the low band is on in first in this situation. That's why I asked.
 
Indeed, it is a full manual valve body transmission build by JVX. With external transbrake.
 
Indeed, it is a full manual valve body transmission build by JVX. With external transbrake.
Is it a real low band apply. There could be a very slight delay if the servo and the clutch pack are both applying because of more fluid volume required.
 
Evertime we were checking the fluid level in park. After the indications by you guys I check the level un neutral, and indeed it was missing like half a quart of fluid. After this it stopped having that short delay.
I have a deep pan, and the trans cooler is all the way to the front of the vehicle, so it takes substancial trans fluid indeed.
 
Half a quart doesn't sound right. Is it all the way up to the full mark and are you checking BOTH sides of the stick?
 
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