Camo Posted December 27, 2006 Posted December 27, 2006 The time has come to raise my hand and say " I have no clue what relays do or how to wire them in " there I said it !I have almost completed the o/d conversion in my Vitesse, but I now need to fit a relay and I have never done this or have a clue what purpose they serve.I chose to live my life in ignorance up to now it must change....I have the box all wired up as per the J type, so please could someone explain the relay to me and where I need to connect !!thanksStuartps the gearbox swap was a bitch, took way longer than expected with the bracket being the main problem..eventually fashioned one
Richard B Posted December 28, 2006 Posted December 28, 2006 I can't remember the codes on the relay terminals but here's a rough schematic. Hope this helps. Basically the D Type solenoid will draw more current than the OD switch can handle and would burn out the contact in the switch The J'type solenoid does not have this problem as it draws less current when engaged.
ferny Posted December 28, 2006 Posted December 28, 2006 A relay is simply a switch. As Richard said, the contacts in a normal switch will burn out due to the high current running through them. Relays will also have to be bigger to deal with this current and as they can be pretty big if they need to be having to manually switch them can be a chore. So what they do is wire it in to another smaller switch and operate from that. So a relay is a switched switched. They're also used in electronics, immobiliser, etc and come in all sorts or sizes (some huge, some tiny) and flavours (here's just a small amount and some more) because they will work when wanted by you or whatever else is using them. Have a look in a Club Torque from about three months ago. There was a car alarm and immobiliser towards back which uses a relay. Might help understand them a little more. My description is probably a bit lame as I've got a fuzzy head today. :)
Freebird Posted December 28, 2006 Posted December 28, 2006 StuartI hope the attached photo and blurb will help you. This is a Lucas 6RA relay, which is standard on my '69 Vitesse and available from people like Canleys, Rimmers or Wins.The bottom right terminal (W1) goes to the fuse box. This supplies 12 volts to the relay all of the time.The top left terminal (W2) goes to the overdrive switch whch should be wired in series with the 3rd & 4th gear inhibitor switch to earth as shown by Richard's schematic above. The top right terminal (C1) is connected to a terminal on the ignition switch which is only live (12V) when the ignition is turned on. You may need to use a multimeter to get the right one, mine has a brown wire.The middle terminal (C2) goes to the solenoid on the OD unit itself, the body of which is earthed.When the OD switch is operated it earths the relay via the 3rd & 4th gear inhibitor switch. Provided the car is in 3rd or 4th gear, this makes the plunger inside the relay pull in and connect terminals C1 & C2 together. This in turn energises the solenoid on the overdrive unit. It takes a lot of current to do this on a D type which is why a relay is necessary.CheersGlen.
Camo Posted December 28, 2006 Author Posted December 28, 2006 Brilliant !! this is exactly what I needed guys, you're the best. The gearbox is now in and the car running, clutch is perfect and theres no crunching gears, so once I get a relay I shall wire it in. cheersStuart
Camo Posted December 29, 2006 Author Posted December 29, 2006 Job done, she drives 100% better than she did !quieter, smoother, no clutch judder too what a massive improvement. I almost can't wait to drive to work next week and really put the O/D to the test, thanks again.I actually understand relays now..I do have an oil leak from the head gasket which seems to have really oiled up the insdie of the old gearbox as the picture shows :
Freebird Posted December 29, 2006 Posted December 29, 2006 StuartThat oil is much more likely to have come from from a rear crankshaft seal leak than the head gasket mate. Your clutch judder was probably caused by oil between the pressure plate/flywheel and the friction plate.The bad news is that it will return after a while. How long before it returns depends on how bad the leak is. I say drive it and enjoy it. It could be years before it needs attention.Glen.
100+ Posted October 31, 2007 Posted October 31, 2007 Glen,I'm just about to fit a relay into my D type wiring, and I'm confused by something.By the diagrams above, (which tally with those in the Haynes manual BTW), the oomphing current needed to activate the O/D solenoid comes from C1, the Ign switch, (starter sw term 1). Wouldn't it be more logical to use this power to feed W1, to activate the RELAY, and then take a direct feed from the fusebox to C1 to connect with C2 when the relay is activated, and thence onward to the solenoid and then to earth via the casing?Or can the Ign switch feed wire handle the necessary current to feed the solenoid?What am I missing here? Also, and really pushing my luck here, rather than pay over the odds for a classic 6RA relay, I am going to hide a 40A Single pole, Normally open relay from Maplins, which has connections 30, 85, 86 and 87.Can I confirm the relationship with W1, W2, C1 and C2 as follows?W1=85, W2=86. These would make the relay activate.C1=87, C2=30, providing high current output to the solenoid.Phew, hope that hasn't confused the whol issue!Cheers, Russ.
Richard B Posted October 31, 2007 Posted October 31, 2007 All the current would then come via the ignition switch; there is a strong chance you would then burn out the contacts in the switch.The idea is to use the ignition switch (and the OD switch and the inhibitor switch) to control when the O/D is engaged, but to use the relay to switch a heavier feed direct from the Battery/Alternator.
Pete Lewis Posted October 31, 2007 Posted October 31, 2007 make sure the D type operating solenoid plunger travel is set to the book as incorrect stroke will pull excessive curent all the time , it only pulls a high current around 10amps on initial travel and then drops to less than 1 amp, if the stroke is wrong this drop wont occur Peter
100+ Posted November 1, 2007 Posted November 1, 2007 Richard, my point exactly. That's not how it's depicted above..If, as the Haynes manual and what is written above says, W1 and W2 control the switching, to make C1 and C2 connect to engage the O/D solenoid, where C1 is connected to a switched feed from the Ignition switch, then I agree, you'll be toasting the Ign switch pretty quickly.I'm with you...I think the feed to the relay to power the solenoid should be a wire direct from the fusebox, with control for the relay coming from the Ign switch feed.Right. well that's how I'll wire it up then.Pete, thanks for the tip!Cheers, Russ
Richard B Posted November 2, 2007 Posted November 2, 2007 'tain't called the 'Haynes book of lies' for nothing :)
100+ Posted November 2, 2007 Posted November 2, 2007 Ha-ha! And 're-assembly is the reverse of dismantling' is another prize porky!
Recommended Posts
Archived
This topic is now archived and is closed to further replies.