Technical 1.0 efi low compression

[andburg]

hi guys, car is not mine but a friends, he was losing coolant so we decided to take a look, foud mayo and signs of water leaking so decided to give the headgasket a go. this went smoothly all went back together fine but car wouldn't fire, got spark, got fuel so that led to a compresison test which read about 7 bar which to me seems very low, can anyone suggest anything??

my guess is that the timing may be out, engine turned over freely before trying to start so i dont think there is any valve damage.

if timing is agreed can someome post up the instructions to set the timing plz.

thankyou for your time.

Andy

 

[Luke]

Definately sounds like timing to me.
If you look at the top of this forum section, theres a link on how to repair your uno... Its a PDF of the Haynes manual, and tells all about timing the car properly

 

[NumanR]

7 BAR is Ok for an older engine, (its over 100psi) at cranking speeds. Have you had the cylinder head skimmed? If so did you remove the plugs first or replace them afterwards? The lubricant they use when skimming seriously screws up spark plugs if they are left in the head. If this has happened then try new plugs first.

 

[Morty Mort]

Comression is ok *IF* it is about the same on all 4 cylinders. I guess your timing belt has slipped a few teeth...

Morten.

 

[Chas Uno]

Unlikely to be any valve damage as the 1.0 litre FIRE engine is 'fail safe', meaning that if the cambelt snaps then the valves won't hit the pistons.

To change the head gasket would have meant removing the cambelt, distributor and possibly the inlet and exhaust manifold.

If the engine turns over, petrol flows and there is a spark then it sounds like either valve timing (cambelt), ignition timing (distributor) or possibly an air leak somewhere.

Make sure the cambelt timing is set properly, then check the ignition timing. Thing is, the ignition timing needs to be set dynamicaly, meaning it needs to be done with the engine running and with a timing light. It can be set staticaly, but I'm not 100% sure how. I think you align the rotor arm on the distributor to point to a mark on the distributor housing when the crankshaft timing marks are aligned.

You can find the crankshaft timing marks and also the flywheel marks by removing the square plastic plug on top of the gearbox bellhousing near where it joins the engine.

Also make sure the distributor was fitted correctly, as I think it's possible to fit it 180 degrees out.

As Luke1985 mentioned, you can download the Haynes manual in a PDF file which will have all the information needed.

Check as well that all the vacuum side of the engine is correctly connected and not leaking. Even something simple like the vacuum pipe from distributor to carburetor can cause the engine to not run properly and may cause poor starting. If you removed the intake manifold make sure it is tightened to the correct torque settings and with a new gasket.

Other than that, just make sure that everything that was disconnected when removing the head is reconnected correctly!

Best of luck,

Chas

 

[andburg]

the uno manula requires a username and password to download anyone know what these need to be??

andy

 

[andburg]

right, I've done the cam timing that ok, I have spark, i have fuel and compression is up to around 11 bar which seems about right to me, yet still she wont fire.

how can i check/setup the ignition timing as this is all i can think off thats left to check!.

if someone could add me to msn and send me the unomanual I'd be much obliged.

andy

 

[Chas Uno]

Hi Andy,

I can't help with the downloading of the PDF file as I haven't done it myself. I have the real manual! Maybe someone who's downloaded it can help Andy?

One other thing to check before you do anything else. Are you sure the fuel is reaching the cylinders? Turn on ignition, crank the engine over a few times and blip the throttle. Then take one of the spark plugs out (making sure the ignition is 'OFF' obviously). If the plug is wet, then you have fuel entering the combustion chamber. If it is dry, then your problem is that fuel isn't reaching the chambers.

The fault then must lie in the throttle body itself (assuming all else is correct). I'm not familiar with these as all my Uno's have had carburetors, but make sure all the wiring is reconnected as it has (I think) some stepper motors used to control it. Also check for obvious things like a blockage in the small filter in the throttle body if it has one.

One thing that surprises me is that you get no firing at all. Even if the ignition/ cambelt timing is out you should at least be getting a backfire. Therefore if your plugs are dry then it must be a fueling problem.

Bear with the forum in responding to your answers as most are not online today. They are all up at the Auto Italia Festival in Stanford! Except me

Anyway, check your spark plugs and if you are still having no joy then post again on here. We'll get your friends Uno up and running again soon!

Chas

 

[Morty Mort]

Also make sure the distributor was fitted correctly, as I think it's possible to fit it 180 degrees out.

Chas. Just a correction... It can't be fitted 180 degrees out. The "dog" thing is offset and if you want it mounted wrong you'd have to hammer it in place.

Just mentioning it so there is one less thing to check for Andy.

Morten..

 

[andburg]

as said there is fuel, as the plugs are wet, compression is a health 11psi accross the board and i definately have spark..i know this because i manage to shock myself while testing for a spark

^^idiot managed to touch the pliers he was holding the lead with

if anyone has any suggestions I'd love to hear them, it almost fires you can hear it, just refuses to fire, wont bumpstart either

 

[alexGS]

Ah but Morten... a correction to a correction...
If the drive dog is removed from the distributor shaft and refitted 180-degrees out... you see?

Generally I take the distributor apart while it's off, which makes things that much harder to rely on when trying to get the engine to start.

Amazingly there's often a problem with flooding after putting an engine back together (in my experience). So, faced with the symptoms, I would recheck all the timing marks (e.g. the one of the cam wheel should be at about 17-minutes-to-the-hour, the flywheel should be at 0, and the distributor should be with the rotor arm pointing to the arrow on the plastic shield). Then, I would hold the accelerator all the way down while cranking the engine, to allow the excess fuel to clear.

-Alex

 

[Morty Mort]

Ah but Morten... a correction to a correction...
If the drive dog is removed from the distributor shaft and refitted 180-degrees out... you see?

Ah...yes. Never dismantled one, so bear with my incompetence. I bend down and face the gravel...

Mrten.