Engine starts but will not run

[woolfie1948]

Thanks to both - lots to consider.
However, all ignition parts recently replaced and we run on super fuel (that I think is 97) plus octane boost. I think the handbook says 97 in town and 100 for high speed.
Dwell book is 40 and when I first started the engine with the 'new' distributor was 30 and I immediately changed it to 38 which is within tollerance - and will allow for a little wear as suggested.
I am driving with both vacuum pipes connected.
Not really sure but I think the performance drop is at lower revs as the auto seemed to change down earlier probably due me pushing harder when accelarating in top.
The old dizzy was still pinking driving with both vacuum pipes on when set at 6 btdc with both pipes off
I set the timing with both pipes off the dizzy and ticking over at around 6-700

[woolfie1948]

Update
Just been down to garage and put timing light on and guess what - at 2500rpm the mark does not move from 10 btdc set at idle!
I assume this means the cetrifugal advance is seized.
I suppose the only thing to do now is to put the old one back on and see what effect backing it to less than 6 btdc has.

[woolfie1948]

Original dizzy back on.
The dwell was 42 now set at 38.
The timing now set at 5 btdc at idle that is somewhere around 25 at high revs.
Tickover seems a bit smoother and definitely a bit faster - now reset at book 700
Test drive to follow.

[woolfie1948]

Test drive quite good - now very much more responsive and feels much better to drive, unfortunately however still not killed the pinking, but not so loud.
Temp gauge goes up (not to the orange) and tickover slows when at long stops at traffic lights.
Overall much improved and I wonder how much is due to the wider points gap and how much the retarding of the ignition? May try a bit more of both but which one first?
Anyway I do feel progress has been made today, my thanks to all.

[arcturus]

The temp' rise seems to be quite normal for some reason. Get the dwell right before messing with timing

[swedishandgerman]

Good news!

Are you able to tell me what rpm she's pinking at please?

In your book, what rpm does it suggest you should set it at 10 degs? To me, 5 or 6 degs at 700rpm (in theory) should be nice. But 10 degs at such a low rpm is a lot. I'd expect 10 degs at about 1,000 rpm. All said, I'm not familiar with the B30 or what its advance curve should be

This is just another thought, but are you absolutely sure your carbs are set up correctly? I absolutely swear by setting the ignition absolutely preperly before looking at the fuel. BUT if there's too little air flowing through one carb compared to the other, you might get a weak mixture in the affected chambers which could, in theory, cause pinking. Additionally, if the vac take off is off of the slow running carb, there's too much vacuum, so if you're getting pinking right down at low rpm, in theory, that could be the cause

You MUST set up the ignition proper job first

If you can't sort out the pinking by fiddling with your distributor and without retarding it so much that it's sluggish, re-post and I can offer some good techniques on how to succesfully set your carbs up. Is it SU's on that car?

[swedishandgerman]

I just noticed a mistype in one of my posts:

Originally Posted by swedishandgerman

I wouldn't go any more than 34 degs full advance. 23 degs should beabout right, but if you're having to go below 30 degs or so

It should say 32 degs should be about right, not 23. Sorry for the confusion...

[arcturus]

Originally Posted by swedishandgerman

I just noticed a mistype in one of my posts:



It should say 32 degs should be about right, not 23. Sorry for the confusion...

A bit to much falling down water?

[woolfie1948]

Thanks both for your further input, much appreciated.
Difficult to say what rpm as it does not have a gauge on the dash but I would say low as it happens most uphill in top gear before it drops a gear.
Both Volvo green manual and Haynes say 10 btdc at 600-800rpm.
I think the carbs (twin Strombergs) are good, as reconditioned last year, and the plugs look to be similar colours.
I don't know the relationship between ign timing and points gap but it has just occured to me that maybe(?) my dwell meter may be faulty?
I set the points gap to 0.25mm (book) on both dizzys when they were off the car so was pretty confident they were correct until I put the meter on and got a reading of 30 instead of the book 40 +or- 3.
I then closed the gap a bit. As mentioned before 38 seemed better than when prviousely at 43.
My meter is very old and second hand so I think (as i don't have access to another one) I will experiment with setting the points to book gap with the feelers (as I always used to in my youth when I could not afford to buy a meter) and see what that does.

[swedishandgerman]

I love this process of elimination. OK - set it at 38. Try not to let it go too muchlower with mileage or your points and condensor will deteriorate quicker. Your timing will have changed by reducing, so re-adjust that too

If it's pinking at very low rpm, like 1,000 - 1,500rpm, then I'd consider what's going on with the vacuum advance

As discussed much earlier in this thread, you have a vacuum advance AND a vacuum retard on your distibutor

This is what I'd do if I was you

Firstly, I would disconnect that vacuum retard, plug the hole and forget about it! The vacuum retard system does less than four fifths of f**k all with how the engine runs. In fact, in theory, it could well reduce performance. The purpose of the retard unit is to burn any gases in the chambers (strong mixture) caused when the throttle suddenly snaps shut at reasonably high rpm, like going down hill or changing gear. The vac take off for the retard unit is so positioned that it provides large vacuum and the unit on the side of the dist only operates at high vacuum. It's sole purpose is to reduce emmisions, but it impairs performance too as if there's enough vacuum in the manifold, it'll retard the timing, even when the engine's running fast, which is when you want good amount of advance provided by the mechanical advance on the distributor shaft

Now to the vacuum advance unit. Very weak mixtures require advanced timing. Weak mixture happens at low rpm and slight throttle openings. Unless something is very different on a B30 distributor than those fitted to a 4-cyl B18 or B20 (I can't imagine there is any difference), the advance curve on these cars is mostly governed by the mechanical advance. The vacuum advance ONLY shifts by about 3 - 5 degrees advance JUST when the throttle begins to open, but when that bit of vacuum reduces again, the vac unit returns. THAT, and only that, is the useful purpose of a vac advance unit. However, there's a good amount of vacuum in the manifold under load, like climbing hills at low rpm or like yours, just when it's about to change down a gear on a hill (auto or manual). So you could get pinking then

Seeing as the advance units on these cars give such a tiny, tiny bit of advance, for the sake of an experiment, disconnect the vac advance and plug the tube, drive it and see what it's like! Fuel consumption may increase slighlty, but I doubt you'll notice much of a difference in performance

Re-post your findings and I can provide further comments on how to improve things if succesfull. We want to be able to get as much advance at 2,500rpm rahter than compensate for pinking at low engine speeds