Bypassing the combo relay????

[canada karl]

Is this somehow possible? The 61311358269 relay is NLA. The latest one 1363273139 is also NLA. The relay I removed from car is 0332514120 which is used in Porsche 914, VW Beetes from the mid 70's and some Transporters T1 and Type2. This is also NLA. Is there a way to temporarily bypass this relay or put fuses in somehow????? I need to start the car to move it. I've checked everywhere with no luck.

[Lock]

I still have the combo relay I removed when I switched to Motronic EFI. If you want it and can cover the cost of shipping whatever that is, PM your address, I'll send my paypal address and I'll mail it to you. It's the newer black plastic type and it worked when I took it out of the car. I was meaning to put these leftover pieces in the "for sale" forum.

I plan to reuse my old engine and with the e12 igition system, but with a carby so I was going to rewire it for a single relay.

To answer your question as Mike has said if someone sat down and reverse-engineered the wiring diagram it's likely it could be reconfigured to use two separate relays, I've opened up a metal one and there's nothing additional in them besides a few passive components. I'm surprised no one has done that after 40 years.

That was my fallback plan if the combo failed.

[Mike W.]

Karl, why exactly do you think the combo relay has failed? What is it doing or not doing? Lets start from the beginning and not midway.

[canada karl]

Mike I did send a post called No start Update but maybe you did not see it? i was able to take the circuit board out of the relay and it looks like some of the contact points are degraded. I checked some of the posts in the archives and it seems that there is a high probability that the combo relay is the problem. I probably should have performed other tests first but I was not familiar with what order I should do them in?

[Mike W.]

First thing is I would check for spark. It's independent of the combo relay and you should have spark. The FI system does get an input from the ignition system to trigger the injectors, so you would not have fuel if there is a dist problem. Are you still running a points and condenser ignition? I'd change them out first just cause... They weren't the greatest system.

[canada karl]

Well I'm not getting spark at the plugs and i am running points and condensor. I'll have a look at the points to see if they are pitted. Maybe I can clean
them up with some 1000 grit paper. Not sure if I have a good set of points kicking around But I will have a look. Could be a bad condensor as they have been known to fail? I have a few of those but hard to tell if they are any good? I do have a complete Petronix Dist in my other car. I could swap that in to see what happens.I didn't install that unit so does the rotor point to slightly before No 1 cylinder when the dist is inserted and when it goes in it will seat in the correct alignment? Just the red and black wire to hook up correct? I'll order new points and condensor.

[canada karl]

I just reread the distributor removal and installation procedure in the manual I must have been thinking of the dist install on my TR3 in my last post. I'll swap in the Peronix unit and see what happens. I'll order points and condensor for the other unit. I'll post the result.

[10ringarcher]

I am also in search of a combo relay. I have a newer plastic black one that works intermittently. Most of the time my fuel pump will only turn on when I run wire from the fuel pump terminal straight to the battery. I am starting to suspect a problem in/under the fuse box. I'll have to check that, but least this allows me to start it and get it running. Maybe you can try that to troubleshoot?

[canada karl]

Thanks for the tip about running a wire from the fuel pump to the battery. I will be changing out the points and condensor soon which like Mike mentioned is probably the real issue of the no start.

[Mike W.]

I hope you guys get this figured out because I looked at the schematic for it and I don't want to have to reverse engineer it. I've done worse, but I'd rather not.

Curious they didn't learn. While I never had any problems, the combo relay is a known weak link. And on E28s, the "Main" relay, which while the generic ice cube size and not expensive, kind of does the same thing, and is noted for being a weak link.