Uno Timing?

[Friendly guy]

Hi everyone, the newby here. Hope I'm on the correct posting section...

I baught a Uno (156A2000 eng number) which was in terrible condition engine wise. I've redone the whole engine eg, 24 thell oversize pistons, mains, bigends, ect. Even did the carb kit replacement and sanding warped aluminum vacuum thingy on the front of the carb.

So on Friday I was on my way home from work and the car just died, when i got home i started searching. The coil and distributor had power and i taught it was the box thingy on the distributor so i started stripping and found all the internal organs of the distributor had seized up and broken everything inside. I baught a whole new distributor but now the car is lazy... I don't know if it's the timing degree thats too advanced or retarded, some say it must be 3 degree without the vacuum advance and some say it must be 7 degrees, if i put the vacuum line back on it jumps to about 11 or 12 degrees... Any advice?

Hope you all have a wonderful day/night.

 

[s130]

I think the 156A200 is the Uno 45... 1000cc engine.

I don't have all my old Uno workshop manuals any more. Also never had the 1000cc model, only the 1300cc. That said the basic engine block and head i believe were essentially the same and only the cc and valve timings changed.

I seem to recall static advance of around 5 to 10 degrees, but no more. The centrifugal advance and vacuum advance obviously increase to around 15 (degrees).

Suggest you start from scratch.

o check the distributor bob weights are free to move and do move the points plate accordingly
o set crank pully to 5 degree advance mark and using test light across point twist distributor till point open and light come on
o engine should now start and run - at idle the vacuum advance should be none/negligible but test by pulling hose off
o with a timing light you can now check that the centrifugal and vacuum advance work separately. With vacuum hose of increase engine rpm and timing should advance. At idle suck on hose and check timing advances. Put vacuum hose back.
o final blip rev and smoothly rev engine and check it advances as expected

Now you have a working 5 degree refence point. I would then with engine at idle advance the timing to 10 degrees and go for a drive listening for detonation / pinking. Do this at low RPM when one could hear the clanking/pinking noise. Then drive at higher rpm speeds in 2nd & 3rd gears listening for pinking (windows down). At high rpm then any pinking/detonation will sound like a tinkling noise / small washers rattling around.

You also said that you have change the pistons / cc etc then I assume your replacement carb kit had bigger fuel jets?

On my Uno SX when I messed with air filters and fuel and timing I found that 7.5 degrees was the "sweet spot". 8.5 would just bring on tinkling when the engine was really hammered. 5 degrees or below was very lethargic/sluggish.

 

[Friendly guy]

Thanks alot for the reply, i will have a look at all those things. I've set the timing at 7 degrees last night with vacuum advance off and i made it a bit richer on the fuel screw and it ran better this morning though it has a flatspot when i release the throttle and step on it again.

About your question about the jet, no it did not have a jet included but i have a few on hand. It had a 115 jet in and it ran too rich on those testers so they suggested i put a 95 jet in which i did (before the distributor seized up) and it was very light on fuel and it ran nice.

The speed pump is also working fine.

I dont hear any funny noises on engine while driving or when idling.

Maybe its still too lean and i should put it on the tester again?

Have a wonderful day!

 

[s130]

Thanks alot for the reply, i will have a look at all those things. I've set the timing at 7 degrees last night with vacuum advance off and i made it a bit richer on the fuel screw and it ran better this morning though it has a flatspot when i release the throttle and step on it again.

About your question about the jet, no it did not have a jet included but i have a few on hand. It had a 115 jet in and it ran too rich on those testers so they suggested i put a 95 jet in which i did (before the distributor seized up) and it was very light on fuel and it ran nice.

The speed pump is also working fine.

I dont hear any funny noises on engine while driving or when idling.

Maybe its still too lean and i should put it on the tester again?

Have a wonderful day!

Sounds like you are making a little progress.

Bear in mind that before your distributor packed up I think you said everything was fine? If so then jetting and mixture is probably not the problem.

The flat spot between release and pedal down again could be the accelerator pump not working correctly either delivering too much or too little fuel. Also the float level in the carb can have major impact on correct fuel delivery.

Not sure what testers you are referring to? If the general MOT style testers then they are OK for idle rpm and fast idle/higher rpm with no load but I don't think??? they are up to the capabilities of a rolling road tester which can monitor/test in greater detail under load.