No boost in manuel Low 1 & Low 2

[boostmaster]

Okay I took pressure readings today on my trans and I don't have any boost in manuel low 1 & 2. All shifts are firm but at wot the pressures are @180psi and remain there through all shifts and does not change. The pressures read as follows and are taken @ 1000 rpm.

min max

Park 110psi - 180psi
Reverse 180psi - 210psi
Neutral 110psi - 180psi
OD Drive 110psi - 180psi
Drive 110psi - 180psi
Low 1 170psi - 170psi
Low 2 150psi - 160psi

Now the funny thing is after playing around with the TV cable double and triple checking my readings my pressures drop lower and now I dont get any boost at all. I already have the .500 boost valve and the bigger low reverse valve installed with a 13 vein pump. Any help will be appreciated.

 

[jakeshoe]

Possibly the transfer tube on the VB.

What about pressures at a little more rpm, 1500-2000?

 

[boostmaster]

pressures!!

Did not test them at higher RPM's at idle but I did notice that with gage installed when I would move my car in reverse it would go up past 210 psi. But as I stated the only true test at upper rpm's was at wot and pressure stayed steady at 185 psi with no increase or decrease.

 

[WE4]

Ironic..

That the int boost valve in pump works rev, 1st and 2nd but the transfer tube on the VB works 1st and 2nd only. Hrmm ...Tells you somethin huh? It "appears" the boost valve in pump is working (rev pressure is up) nso, transfer tube sounds like a good place to start.

Bruuce
WE4
PTS XTREME

 

[boostmaster]

Boost

Today I took the pan off and checked the transfer tube on the valve body. I took it off and blew thru it it was'nt clogged and had not wiggled loose. Put everything back together and still no boost in low 1 or 2. Is there anything else I should check? What are all the things that could cause this.

 

[WE4]

Hrmmmm

INT Boost valve in pump. ahh.. Huge leak in L/R clutch but that I would think would only be low gear not second, so recant that.
Hrmmm The failsafe mechinicnism (sp) might be cocked or screwed up somehow. Ahh Crack in pump casting or crack in VB... ahh Oil starvation possibly?

Chris? Greg? Any other ideas?



Bruce
WE4

 

[boostmaster]

If by chance there could be a clog somewhere would it be of any benefit to get the tranny flushed with one of those trans flush machines. And how would I check some of the things you mentioned. As I stated above this thing shifts solid with no slippage.

 

[WE4]

Naaa. that is not it and I would not reccommend the flush thing.
Bruce
WE4

 

[Ttype83]

Check with ROB at A&I AUTOMOTIVE

770 972 1122

He is just passed Stone Mont. on 78. Well worth the trip, I spent about 2 hours in his shop last week.

Jim