Irratic timing

[kangarolf]

Hi all,

I am currently trying to get an alternative engine to run in my morris whilst I recondition the original (bit of an oil leak and seize situation!).

The car starts fine from cold but we cannot get the timing right. I will try and explain the problem.

Start of locating tdc then use a strobe and try to get the light flashing on the third prong. Firstly its very erratic..timing doesnt seem to be consistent and the strobe point moves around..dont know how much consistency there should be.

So set it as close to 3 degrees as possible and tighten up the distributor assembly.

Starts..runs but very erratic, sometimes it seems to be driving itself and th e revs and mix seem to increase then die off and then it stalls. The best Ive got it so far is ticking over ok but struggling up hills...not quite pinking but almost and then the odd misfire!

I have cleaned the plugs, checked the mix (Seems ok and it doesnt seem to be flooding), checked the choke cable and it does fully retract.

What else should I check...?

Thanks in advance for any help..also have a question about wheel spacers which I'll post in the next topic.

Rolf.

[Willie]

Have you grasped the rotor arm and turned it as far as possible
against the spring pressure and checked that it returns to the original
position as soon as possible? If you are running a different carb then
has it got the long coil spring inside the piston bowl and is there oil
in the top damper chamber?

[kangarolf]

The carb is the same wil check the rotar arm. Put a new rotar arm and cleaned up the contact/points.

Thanks
Rolf

[bmcecosse]

Sounds like worn dizzy - or weak spring on points. Forget the strobe thing and just set it static. Get it running properly before worrying about the last degree of timing !!

[kangarolf]

Worn dizzy..? as in distributor..? Which part do you mean..?

Will probably do a HT lead/plug/points replacement this weekend see if all that helps.

Thanks for all the help

Rolf

[rayofleamington]

Forget the strobe thing and just set it static

Seriously good advice! Many cars are set wrongly with the strobe as people forget to disconnect the vaccum advance (then you end up setting something, but not the real timing!).
I tend to set to 5 degrees (just using a starting handle and 12V bulb across the points) and then see how it drives. If it drives badly it normally means something is worn out or damaged - if it drives ok, then it is worth to fine tune the timing.

[bmcecosse]

The dizzy shaft can get bent - and the bush it runs in can be worn allowing the timing to vary horribly.

[kangarolf]

Thanks for all the advice..wil check the distributor thouroughly and maybe try and find a replacement just to try it out.

Rolf

[Cam]

Yes, good advice about the dizzy. If you grasp the dizzy shaft (the bit that the rotor arm clips on to) and try to waggle it from side to side then that will show you how worn the drive is. I bet that yours has quite a bit of movement which causes the timing (dwell really) to hover about all over the place. Best bet is a good condition 2nd hand dizzy (loads about).

[Kevin]

Best bet is a good condition 2nd hand dizzy (loads about).

True but most have a shot vacuume unit, so dont forget to check.

[bmcecosse]

Yes - vacuum units are nearly all gone after 10 years - and they fetch massive prices on ebay ! I stupidly failed to buy a brand new one at a classic car autojumble last weekend (wife was with me - meant to go back later on my own !) - lad only wanted £5 for it. Hope it's at the next show !! In theory they are all different settings - but beggars can't be choosers - any working one is better than a failed one.

[Blunt]

so how do you tell if it's a working one?

[Onne]

Suck it, you will feel resistance if it is working (thus building up a vacuum)

[bmcecosse]

Exactly - suck it and you should see the base plate moving if it's in the dizzy.