Can someone help me with finding a pressure switch?


I put a napa pressure switch someone suggested. It engages @ 28 mpg and dissengages @ 25 mph. Too loow! It's a 1/8 NPT?

I ordered up a 50 psi switch from PATC and vola...it's some weird metric pipe thread.


Help with some part numbers? Maybe something around 48-52 psi


Michael

 

Google Hobbs switch you can get them a napa Butt they where about $75 and about I think they where about $30 at one of the other dist. they have ones that are NC or NO ones that arent adjustable and ones that are adjustable. i would put a pressure gauge on it befor I got a pressure switch I was told and read that 727 46 47 ran 1 psi per mph at the gov port mine ran about 10psi higher and later my budy with a trany shop told me the diesel run 10-20 psi higher than the gasser tranys. I would get a adjustable one ken

 

Thanks ken- maybe that's it!

I'll have the trans shop tell me the pressure and order up a correct switch. I guess I want one that closes @ 50 mph. NC? or NO>

mike

 

Are you using the switch to engage OD or lockup? Just wondering.

 

your going to want a NO switch and I would get the LU kick in about 40

 

well rule of thumb aparently is 1psi per mile per hour. iam just installing my rebuilt 47rh now and have a switch on order ill post up a part number tomorrow its a 35 psi one.

where do you get adjustable ones?\

post you part numbers please

 

http://content.honeywell.com/sensing...scorp/P3_6.pdf and here http://sensing.honeywell.com/index.c...154022&la_id=1 I cant gave a P/N as did this over a year ago. Dont go by the rule of thumb put a pressure guage on it! If you put the pressure switch on it and it wout turn the lockup off whene you try to come to a stop you are going to need to go into the valve body there is a transgo fix for that . ken

 

i have a dunrite valvebody.....allows lock up in all gears.
if you wire it right you can have 3 modes

locked up permenatly when switch is on =good for steep 1st gear down hills and smoking out the ricer next to you.

automatic running off the pressure switch. for the wifey

and lock up off if you are having issues

if the n/o switch is set at 35psi it should open around 35mph.......unlocking the converter.

i have heard if you go with a switch 40psi or higher when you sudenly let off throttlr on freeway it will cause a lock/unlock/lock situation

 

Guys,

I found Mouser.com and Digikey.com carry some of the honeywell pressure switches. Ideally, a 83316 would be perfect(30-90psi, preset @ 60psi). Couldn't find it- but they have a 25-50 psi adjustable, 1/8 NPT, screws for the connections. It costs $33 + $8 for the cap.
If anyone can dig up a mail-order place with the 83316.

My concern with the 50 psi max, is if someone did valve body modifications- maybe it's running a higher line pressure.

Michael

 

parts number 76073

25-50 psi set at 35psi factory, adjustable
made by hobbs
owned by honeywell /stewart warner

i ordered mine threw a local canadian parts store who is a stewart warner dealer.

tranny is in BUT I HAVE NOT YET TESTED THIS SWITCH

 

I think that's the same p/n that digikey had instock.

 

That pressure switch did not work for me, the preset is the psi around when it would engage/disengage, causing hunting, ie lockup on/off. You need to get an AC type cycling switch, ideally one that opens around 45 and closes at 60. I found the one i'm using but forgot from where i ordered it. Ill try to dig it up.

Edit: I'm using a Supco AC cycling switch SLP4560, you can find it in Ebay.

 

Hey Ken,

Maybe I'm experiencing this "if the n/o switch is set at 35psi it should open around 35mph.......unlocking the converter.

i have heard if you go with a switch 40psi or higher when you sudenly let off throttlr on freeway it will cause a lock/unlock/lock situation"

I'm not sure. But I've got it set to engage about 38-40 mph and it disengages when I let off the throttle. I'm getting tired of throwing money at switches.
Is the SLP4560 got 1/8 FIP threads?

Michael

 

I'm getting tired of throwing money at switches. - I know the feeling :-)

Is the SLP4560 got 1/8 FIP threads? - YES (edit, it's 1/4 female but you can easily get a 1/4 to 1/8 adapter at Ace hardware).

 

by the supro part number in at 60, out at 45...

I guess I'll see if they have a SLP3550 or 4050 etc. The honeywell switch engages fine.. just doesn't hold. I've got a defeat manual switch in case I'm pulling or a big hill etc. Then I can choose to shut the TC and/or the OD off.


Michael