92 740...how to check O/D solenoid?

Re: 92 Volvo 740 turbo is not going into overdrive:

I removed the O/D solenoid from the side of tranny. WIth iginition ON
and O/D button IN to enable O/D, I have good power (test light) right
at the solenoid. I have to touch the solenoid to the tranny pan of
course, so that it will work. It is drawing quite a lot of amperage, I
can tell. However when I cycle power I can feel little if anything as
far as a vibration indicating that maybe it is activating. I hewar
nothing. I thought it would probably have a very noticeable vibration
and "click". The only way I will know for sure if it is good is to
somehow see if fluid is alternately passing/not passing through the
ports. They are very small, and I don't know how I could do this. I
would need some VERY thin plastic tubing of just the right size to jam
down into one of the ports. I guess there is a good chance the
problem is this solnoid and not the tranny itself.
But ...can the kickdown cable be so mis-adjusted as to prevent the
O/D from kicking in?

Ideas?


Geronimo

 

Here is a wonderful 740/940 FAQ site. At the bottom of the page, down arrow
on the popup pn the right to link to transmissions.

Here is a wonderful 740/940 FAQ site. At the bottom of the page, click on
the down arrow on the popup on the right to link to transmissions.

http://www.brickboard.com/FAQ/700-900/

Happy Thaksgiving,
joe

 

It should make a soft click as it engages, and you should then be able to
blow air in one of the holes and it will come out the other.

 

Give this URL a shot:

http://www.brickboard.com/FAQ/700-900/

Scroll down to the bottom to the two pull down menus.

joe

 

Yes, the solenoid does pass air when I energize it with my batt
charger. The only fix is to replace tranny? There was no gasket on
the solenoid...I just hope it seals when it goes back on!
Maybe a power flush might help? Its a big gamble as a powerflush
costs a lot!

 

There's an O-ring that seals the solenoid, it may be stuck to the tranny
still if you don't see it.

You could flush the tranny yourself, it's not too difficult. Might be worth
changing the filter as well, that's an odd problem though, I don't think
I've ever come across one that wouldn't shift up. You're sure the kickdown
cable and shift linkage are adjusted right?

 

Not really sure about the kickdown cable...would misadjustment keep it
from going into OD?

 

Yes, and prevent it from shifting up to other gears as soon as it should.

 

That's probably what is wrong. Is it hard to replace it? I just
replaced the rear brake calipers...boy was that easy! (maybe
brickboard has the procedure in their how-to's) thanks!

 

I've never replaced one, usually they just need cleaning, lubrication and/or
adjustment.

 

Geronimo,

I had a 90' 765 that had the OD solenoid fail and I replaced it with
one on ebay and it was bad I finally got one that worked but it will
prevent the transmission from going in it's final gear. I tried all
the methods on Brickboard to determine if it functioned and they all
passed. The kick-down cable really has little to do with it. I mean
if the cable is at least somewhere in the ball park the tranny will
eventually shift. I bet its the solenoid. Those AW 70/71 trannys are
bullet-proof. I've never talked to anyone who had one that failed it
was usually the electricals that failed.

Bernie Franklin