Easy way to check trans line pressure

[Garys1969RR]

Yes, the front Allen head screw on the valve body is used to adjust line pressure. You turn it counterclockwise, which moves that plate, which compresses the line pressure spring. That results in more line pressure. I have ordered a stronger spring from A & A Transmissions, which I will install soon.

 

[Garys1969RR]

The throttle pressure adjustment is probably at, or near, the throttle pressure lever. That is hooked to the kickdown linkage from the carburetor. I'm pulling the pan off today, and I will post up a picture of where I think the throttle pressure adjustment is.

 

[Aeronet]

The throttle pressure is linkage adjustment at the carb and the linkage. A manual tells ya how to set it.

 

[Aeronet]

Throttle pressure linkage opens the valve on the transmission when you open the carb's throttle.
I guess that's why you burn the transmission up if you don't hook it up.

 

[Garys1969RR]

In post 3, the manual says to verify that the transmission throttle linkage adjustment is correct, before attempting to adjust throttle pressure. So this makes me think there is an adjustment for throttle pressure in the transmission. In other words, after throttle linkage is correctly adjusted, then you can adjust throttle pressure, or throttle oil pressure in the tranny. Just tryin to learn how this all works, as relates to shift RPM. Thanks!

 

[Aeronet]

Yeah, sounds like they mean that you should adjust the linkage before you adjust the line pressure. I'll look at my books again to make sure. Throttle pressure is probably the same as line pressure.

 

[Garys1969RR]

Yeah, sounds like they mean that you should adjust the linkage before you adjust the line pressure. I'll look at my books again to make sure. Throttle pressure is probably the same as line pressure.

Just read on another thread, that you can adjust throttle pressure with the valve body on the bench, using a special tool.

 

[Aeronet]

 

[Aeronet]

I don't own the factory tool, but I adjusted the throttle pressure. It was a couple of years ago so don't ask me how, but I did and I know it was correct. I'm getting old.

 

[Aeronet]

I think you need a 5/8 gap.

 

[Garys1969RR]

Ok Thanks! Spent the afternoon removing the valve body. What fun! Now I'll check the spring compressed length........ Looks like it is right at 1 9/16.....That's a quarter inch too long, although my line pressure checks within specs. Here's a pic of it. Looks like the adjustment is back all the way against the retainer.

 

[Garys1969RR]

And I think I see what you mean by adjusting the throttle pressure Gap at 5/8 of an inch. Now I don't know whether I should keep this stock spring in there and adjust it to its correct height, which would move it one-quarter inch shorter, or if I should put the heavy spring in that A&A is sending me.

 

[Aeronet]

Hope I helped. This stuff is easier than it looks or sounds.

 

[Garys1969RR]

Hope I helped. This stuff is easier than it looks or sounds.

Yes you did! The pics showing how to set the spring height was very helpful. I also have to set the throttle pressure adjustment, and the pics are helpful too , although I haven't tried it yet.

 

[Aeronet]

I've installed a B&M shift before and adjusted the throttle and line pressure as they instructed (worked great), but that was a long time ago. Recently (two years ago) I rebuilt my 904 to stock specs (no shift kit). What does A&A say about line and throttle pressure with their spring?

 

[Garys1969RR]

They want around 100 lb of line pressure at idle, and about a hundred and forty in kickdown mode. Haven't asked them about throttle pressure yet.

 

[Aeronet]

So more of both I take it. Now you need to know how to measure it. Right?

 

[Aeronet]

I used to live in Denver. Lakewood and Green Mountain. Jefferson County.

 

[Garys1969RR]

Oh really? I grew up over there. So I guess I need to know how to measure the throttle pressure distance without the tool. I held a steel ruler next to it, and it's hard to tell where I'm at. I'll send you a PM aeronet, maybe we can talk.

 

[Aeronet]

You have to compress that valve. So you need something that's 5/8. I'll go look in the garage and see if I can figure out what I did.
Many projects have come and gone since I rebuilt my transmission.
5/8 drill bit? I have other valve bodies, so I'll check.