The Triumph Dolomite Club - Discussion Forum

Hello all!

Today I've been changing my distributor, but have hit a few snags. I managed to get the car running, but I could only get the timing correct if I put the distributor in a position that couldn't be bolted down. So I took the thing back out and twisted the dizzy cam round and now I can't get the car to start. I've tried putting the timing to 0 and fitting the dizzy with the rotor pointed at around 7 o' clock, then used a test light to get the timing at anything from 10-16 BTDC but it just won't bite for some reason. the leads are anticlockwise from bottom left as 1-3-4-2. Now I've run the battery completely dead with attempts. What I would like to confirm is the correct position of the distributor cam? Do I need to take the camshaft cover off and check the timing marks are aligned? Thanks again people!

Back to first principals...cam cover off and identify TDC no1 firing. Set crank to 11 BTDC and then get the dizzy in on the tooth which matches with the body in the middle of the slotted bolt holes and pointing at no 1 plug lead.

Then it will go....do a ballast bypass feed check too and charged battery.

Set the points gap while its out....much easier.

Jonners

With No 1 cylinder at TDC the rotor arm should be pointing at one of the inlet manifold bolts.

Not necessarily....the leads can go in any of 4 positions....
so the dizzy can be rotated to suite.

They didnt all leave the factory the same....

As it ran before there is no need to change the lean positions in the cap. Just be sure you identify which is no1 and which way round it goes....

Jonners

HQ, there are 2 TDC's (or zeros on the crank pulley) Because the crankshaft pulley turns 2 full turns to 1 turn of the camshaft (and jackshaft) one of the zeros can be the exhaust stroke on number 1 cylinder instead of the compressions stroke youd like it to be. If you have set up on No4 instead of number 1 a quick test is : swap 1 and 4 leads over in the dizzy cap then swap 2 and 3. This will then change everything 180 degrees as far as the distributer is concerned. If it fires up you can just adjust the timing and be done with it.

HTH

Tony

There's a diagram in the 1850 manual showing where the rotor arm should point if the timing is at TDC ( remember as Tony says the timing mark on the vernier may be 180 degrees out, and as Jon says the sure way to find out is to look at the valves by taking the cam cover off - I've never been able to figure that out though). I think the rotor arm should point to the second screw securing the inlet manifold counting from the bulkhead. It's been posted on here before but I can't find it.
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Second screw in the bottom row, above. IF your timing is not 180 degrees out and your leads are 1342 and the rotor arm is pointing to the screw above then I think it should be good. I think.
This is all from memory so.........

Hi Kyle Are you changing the 1850 AC Delco distributor for another AC Delco unit ?
If so ......
https://dollywiki.co.uk/wiki/Dolomite_1 ... adjustment

...... should give you a starting point.
I seem to remember you had a Sprint unit at one time. That will be different.
Tony.

Tony, he was planning on changing to the Lucas 44D4 dizzy. He's been picking my brains recently.

Kyle, I hope you didn't forget to fit the adaptor plate because the Lucas dizzy is in a different orientation to the Delco one.

Hiya you lovely people, thanks so much for all your help as usual!

Unfortunately I haven't got very far today. I've had everything to bits but just can't figure out whats happening! One of the new neighbours came out of his house this morning, turns out he's an ex-banger car racer, but still no luck. We are definitely getting a spark, wondering if we have flooded the engine so I have taken all the plugs out and left it to air out for a few hours. Here are some pictures of the situation at TDC, everything looks right to me? We've tried the leads in all positions including 180. Its not even trying to fire though. And yes, I changed to the lucas 44D4 dizzy as you can see!


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Here is how the leads are fitted on a Sprint from the factory (looking end on on the dizzy cap):-




On your photo there is a tab on the dizzy body between the 12 O' clock and 1 O' clock position. This is roughly the position the rotor arm should be pointing with the leads in this configuration.

That no.1 cam lobe (nearest the sprocket) should be pointing in the other direction, similar to no.2 in the photo.

Mart's been looking at too many Sprints...

Thats right for tdc no1 firing on an 8v. Put it back to 11BTDC

So now you want the points just opening and the rotor pointing at no1 plug lead. Then other leads go on in turn
to 3, 4 and finally 2.

Check the ballast bypass to the coil. Dolomites rarely start without this working.

Jonners

True. I've only ever done one head gasket on an 1850, that was donkeys ago. Should have seen the timing mark on the camshaft.

Thanks for all the help again guys!

In the end I bit the bullet and put the original 1850 dizzy back in and she started straight up no problems at all. I think the new dizzy needs some more investigating, although I can't understand how I ever had it working if it has problem. Also out of curiosity, what is the long hexagonal pole for that disappears into the gearbox, connected to the inside of the distributor shaft?

I think it drives the oil pump for the engine, it doesn't go into the gearbox. I think.

Why do you want to change the dizzy?

Yes it's a total pain to look after but you can get a solid state ignition for under £40.00. I've never had experience of these but I've had a Magnetronic in my Herald (they can't touch you for it!) for some years and I have never had to have the cap off.