Thread: Disco backfired this morning on gas :( What to do?

I don't think it has any play but I'm not sure, I just liked the idea of swapping it out for something I know to be reliable. The way I hear it the less Lucas parts you have the better off you'll be

Just relax a bit. You don't need to through money at it straight away with out checking the basics. Do the basics and see how you go. There are thousands of Disco running around out there just fine. Get your leads, plugs and rotor and take it from there. Also a couple of drops of oil under the rotor cap every so often help keep things going too. You can try my Amp if you want to see if it goes ok. Just replaced my coil so I don't have a spare one of those. If you need a hand with the tune one day I might be able to drop over and help (When I'm At Work).

Haha awesome, sounds great

I just took a photo of the tuning scale on the harmonic balancer:



am I right in thinking that the white mark someone has put there in the past is sitting on 2 degrees BTDC? (it does say "before" just above the "12" there). Would this have been for a petrol tune? I heard that petrol likes the opposite tune to what lpg does.

So for lpg I'm meant to tune it to 10 degrees BTDC, that means the little dash second from the top right? Just want to make sure I'm reading the scale correctly because it's hard to see the numbers properly but I'm pretty sure it's going from 12 deg BTDC at the top, down in increments of 2 deg, hence the second dash down would be 10 and is where I'm tuning to.

Does that sound and look about right? Haha I still don't know how I'm going to tune the dizzy anyway, I've never done that before I'd be worried about totally messing it up and not being able to get it back to normal :P

The white mark would be the Std Aussie spec timing mark.
To adjust the timing you will need a timing light, usually they have a + and - leads that connect to the battery, the other lead with clip goes onto the number 1 spark plug lead. Slightly loosen the nut holding the dizzy to the motor block. Remove the Vacuum hose from the vacuum advance and plug the end of the hose. Start engine and aim the timing light at the point on the timing cover. Every time number 1 cyl fires your light will flash.
you will see the timing mark on your harmonic balancer light up from each flash. Turn the dizzy body with your other hand and when the flash lines up with the desired timing mark. Stop car, tighten dizzy nut and re check.
Young Angus it might pay to get a workshop manual for your Disco, it will help you a lot.

Sounds good, I had a workshop manual for my old car and it was a great thing to have.

Are they pretty readily available through the forum or ebay?

Thanks for that advice, that's exactly the advice I needed on how to do it

I just pulled off the leads at the plug end of them and they are pretty old ratty looking performance leads. I haven't got the plugs out yet to check what condition they're in but I'm going to get the tool for it soon as well as a timing light.

There is a little nut on the front face of the base of the dizzy that I can see...is that what you loosen to turn the dizzy for tuning?

One of the plugs that I pulled off was this funny looking thing:



What the heck is that, it's got a bloody spring on it none of the others are like that?!? Also can anyone look at that and tell me which part of that impco gas system I can detach temporarily just so I can get new plugs in to that side of the engine...it looks like it's going to be too hard a squeeze with the tools unless I take some of that crap off.

Cheers guys, today I'm going to sort this out!!!

PS. My rocker cover gasket it leaking oil...LOVE THAT DISCO!

Originally Posted by Young Angus

There is a little nut on the front face of the base of the dizzy that I can see...is that what you loosen to turn the dizzy for tuning?
what the heck is that, it's got a bloody spring on it none of the others are like that?!?
Also can anyone look at that and tell me which part of that impco gas system I can detach temporarily just so I can get new plugs in to that side of the engine...it looks like it's going to be too hard a squeeze with the tools unless I take some of that crap off.
Cheers guys, today I'm going to sort this out!!!

PS. My rocker cover gasket it leaking oil...LOVE THAT DISCO!
Cheap to replace, use the rubber ones instead of the older cork types.

[QUOTE=Young Angus;1204789]

There is a little nut on the front face of the base of the dizzy that I can see...is that what you loosen to turn the dizzy for tuning?

Yes

What the heck is that, it's got a bloody spring on it none of the others are like that?!?
???? Beats me

Also can anyone look at that and tell me which part of that impco gas system I can detach temporarily just so I can get new plugs in to that side of the engine...it looks like it's going to be too hard a squeeze with the tools unless I take some of that crap off.

I have the same system setup, I just reached down between the plumbing with a 3/4" socket set, after you've done it a few times it gets easier.

Tip, be careful not to cross thread the spark plug holes in the head, easy done.When access is harder.
Use some Nickle anti seize paste on the plugs, makes them easier to get out next time.

Cheers guys, today I'm going to sort this out!!!

PS. My rocker cover gasket it leaking oil...LOVE THAT DISCO!
Cheap to replace, use the rubber ones instead of the older cork types.
have look here Rocker Cover Gaskets ( Rubber) set of 2. Suits V8 - eBay Engine Parts, Engines, Components, Car Parts, Accessories, Cars, Bikes, Boats. (end time 21-Mar-10 19:55:34 AEDST)

What part of Melbourne are you in? If your anywhere near Glen Waverely you can come past here and i can do the timing for you with my timing light.Only takes a few minutes.

Cheers

Chris