[TR] Stag overdrive testing

[Stuart Greenwood]

Sujit wrote:-
 I have rebuild a gearbox for a Stag using a Y type  OD from a Triumph Dolomite Sprint.
I'd like to bench test it. Can I put a drill on the end of the input shaft and spin it and then switch on the solenoid?

If so, and I am looking at the bell housing face on, should the shaft rotate in a clockwise direction?
For testing, can I switch on the solenoid in any gear other than reverse?
It just depends on how strong a drill you have and what speeds it goes at. You want enough power to spin the gearbox and overdrive up to a such a speed so that  the overdrive oil pressure is at the relief valve setting ( probably 450 psi though the Dolomite might have been different). I used a 1/2 horse power electric motor from Harbor Freight and a pulley drive to step down  the speed though I can't remember the step down  ratio but I still have the pulleys so I could calculate this if you want.  1/2 horse power was just about adequate... I should have got a 1 horse power motor instead. Most engines turn clockwise looking on the front of the engine and the Stag engine does. How many inhibitor switches do you have on the gearbox? That limits the gears for the overdrive to work. If you by pass these switches you can operate the overdrive in 2, 3 and 4 if your like but was is the point of doing this?. You want the gearbox to be in 4th gear so the overdrive is rotating as fast as possible.I strongly recommend, as I think I have told you before, to look at the Buckeye Triumph web site and read the the article on the J type overdrive. There you will see a bench set up for testing the overdrive.The only way you can tell that the overdrive has switched in is by putting your hand on the output shaft and feeling that it has slowed down. So I hope you have either  a helper or very long arms
Stuart A Greenwood
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/triumphs/attachments/20180810/13ea8115/attachment.html>