Series 3 Urgent carb and timing advice needed.

Hello gentlemen.

Just purchased an '82 SWB Series 3 petrol.

Unfortuneatly I'm really struggling to get her running correctly as she's now undriveable.

I've replaced the distributor, ht leads, coil, plugs and the little metal vaccuum pipe with a silicone one. But now she will not run at all on tickover without backfiring or stalling with any acceleration.

She is fitted with a Zenith carb, I've played with the tickover and the mixture, all done by the book. (haynes manual)

The dizzy was set up by the book too and with a strobe. I even got to the point where I was turning the dizzy by hand without the strobe with slight results but she still will not run correctly.

The distributor was a cheap aftermarket one from paddocks.

If anyone could point me in a better direction (not fitting a 200 engine) that would be wonderful.

Thankyou in "advance" (worried incase that's the problem)

Plug leads in the wrong place most likely.

Order is cast into the manifold, don't forget the dizzy goes anticlockwise starting at the plug at the front fed from the HT lead outlet that points to it. Get that right (we've all done it.....) and if it still doesn't run we'll look at other possibilities.

Hello chaps, just been out in the driveway for a while. Thankyou very much for your suggestions. I got desperate (and lucky) decided to remove the mixture screw on the carb, found a small piece of metal dug into the needle end of the screw. Its not magnetic, so I'm guessing it came from the carb body somewhere. After putting a dab of solder in the pit on the screw and sanding and polishing it back, It runs perfectly!

Thanks for the quick reply's. This is a new one on me, never heard of a carb falling to pieces? Could it be terminal, where to look next?

I've developed a mistrust of the Zenith in my short period of ownership..... I had similar issues to you that appeared out of nowhere; a forensic examination during rebuild showed nothing, yet upon rebuild, perfect running was restored....

Castor said:

I've developed a mistrust of the Zenith in my short period of ownership..... I had similar issues to you that appeared out of nowhere; a forensic examination during rebuild showed nothing, yet upon rebuild, perfect running was restored....

Click to expand...

There are apparently several common problems with these including the actual body warping, a leakage into one of the internal drillings which is meant to be blanked off and spindle wear ofcourse. For the small sum of £9 I got a full rebuild kit, although I couldn't replace the mixture screw as it was a different type.

It now appears that after another 15 miles of driving today, she really doesn't pull and is extremely hesitant and misses beats on acceleration and also when trying to maintain speed.

As previously mentioned she has a rebuilt carb, new dizzy, new plugs, new leads and has just had a second new coil this afternoon.

I've had two coils explode now, they've both been wired correctly, and mounted in the sloping downward position. (as the are from new)

Does anybody know why she's eating coils?

I also cannot get her timed on the strobe with the pointer within 60 degrees of the timing marks on the pulley? She will not run.

Since the rebuild, the mixture screw now sounds like it's doing it's part but altering this does not help the issue of the misfiring under load or speed.

Why do you reckon the timing runs so so far out?

Thanks again.

Either you've got the wrong type of coils they should be 12V ones (not ones that require a ballast resistor) and should measure about 3 ohms across the primary. The other thing you might have done is set the points gap wrong. A dwell meter is worth getting but have a good study of how to set the points gap. It is essential that you set the gap when the points are at their most open. While you're at it replace the condensor with a known good one. There's a lot of cheap nasty ones around that don't work,

Other issues sound like over / under fuelling. When you set up the carburettor you did do it when the engine was up to FULL (stinking hot after a hard run) temperature didn't you....other wise you might as well just shut your eyes and twiddle all the screws.

You will need to spend a bit of time carefully getting each bit right (or at least better) and working through things logically, you may need to repeat things but take it slow and make sure you've got each step right.

Replacing everything at once is tempting but then its nearly impossible to work out which bit is not working or the interaction of the things..

Check the vacuum advance if it's hesitating under acceleration that could also be a problem amongst others. Sounds a really frustrating catalogue of problems.

Another thing to check is the float level in the Zenith. if you set one with nylon/plastic floats to the 33MM setting fromt he LR manual it's too low and the truck will feel like it can't pull the skin off a pudding. Proper setting is 30.5 - 31.5MM from the gasket surface.

Alan