Technical Cam Belt timing

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Technical Cam Belt timing

Phil

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Could someone give me a quick rundown of how to check the timing on the 1.2 8v.
My car has lost power since a garage did the cam belt change a couple of weeks ago. It has no power at low revs and jerky power delivery especially when I dip the clutch. Have stalled it several times and never did before. Still runs up to 70MPH okay and is fine once past about 3,500 rpm. I guess I'm going to require a torque wrench to re-tighten the tensioner if it is out?
 
Me and my Dad recently had to time mine up again the other day as we were replacing the crankshaft oil seal..
Please excuse the lack of technical terms, I am fairly new to engine components! lol
You will need to remove the 3 bolts holding the alternator pulley to gain access to the crankshaft pulley - on the crankshaft pulley there is a roughly 2cm line indicating the timing mark.. We had trouble figuring out where the timing marks were on the oil pump but it is very hard to explain, from the ground upwards it is at about 10 oclock so pretty much facing the drivers steering wheel area, it's a smooth surface then it has like a lip on it. Perhaps if you were to take some photos of the area around the crankshaft pulley I can MS paint where the timing mark is. Luckily mine was tippexed from previous useage.
The camshaft part is much easier... again it is at around 9 oclock this time towards drivers seat,, there are two notches on the rocker cover, the one above is where the rocker cover attaches but below that there is an indent about 5mm further down, this is the timing mark. So hard to explain over typing ha!
As for the tentioner, my Dads a mechanic on weekends as a hobby so he knew how tight the belt wanted to be, I pushed the tensioner whilst he tightened so that the belt springs back fairly fast when it is twisted 1/4 of a turn.
Any of that make sense? lol
 
I just found some pics of it that Dave posted 5 years ago! lol
Crankshaft pulley
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Hi Dan,

Thanks for all the info, I haven't delved into the engine compartment yet, but your advise has spurned me on to check it out. It all makes sense so far. So I have lined up a little job for the weekend!

The loss of power is really irking me, the car was running perfectly before the service and now I'm getting overtaken by everything (even mopeds) at the lights!
Philip
 
If you look closely at that picture you will see the crank pulley has 19 teeth my 02 plate mk2 has 23 teeth
Interesting, I supplied a belt to the garage which came from an on-line retailer. And it had the wrong tooth pitch. Probably was a belt for the mk2 then.
 
Do not use the oil pump method to get the crankshaft at TDC !!!
Although this method is in the Haynes manual it will put the timing a tooth out.
Use the timing marks that are on the flywheel ,which is accessed via a rubber bung at the top of the bell housing. There are photos on this forum which show it clearly.
This is applicable to both Mk1 and Mk2 Puntos.
 
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Thank you for everyone's help. I used the flywheel method to check timing on the camshaft. The timing is exactly spot on, so the garage did the job properly.

CIMG8589s.jpg


For reference, I found this guide for the Panda and expect it to be very similar for the Punto, as its the same FIRE engine:
https://www.fiatforum.com/panda-guides/160358-panda-timing-belt-replacement-ohc-fire-engine.html

Apart form a water pump, the only other thing the car had at the same time was a catalytic converter, so I'm leaning towards this being more restrictive than the old one by upping the back pressure.
 
check all electrical connections/sensors have been refitted correctly and pushed home, particularly plug leads/firing order and ?renew sparkplugs; lambda sensor could also be the problem
 
When the engine is at top dead centre on No1 cylinder, the cams should be both facing up. That is the buckets below should be in the between the start and end points of the inlet and exhaust cams.

On a twin cam they will be facing outwards (exhaust about to start lifting and inlet about the max distance away from lifting.

So on the 8V set the engine at TDC and lift the cam cover. If No 1 cam angles look symmetrical, the timing is ok.

As TT says, there are lots of other things to check before you get into heavy duty spannering.
 
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ever since i changed sump few months back, car isnt running as it was before, like its running rough on idle and also makes strange sound when started which wasnt there before

only thing i touched was timing belt, so i had to time it

today i timed it again via hole in gearbox and cam notch as seen on those panda pictures
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are these correct timing marks for punto?

if that timing is correct what else can be causing car to run rough immediately after sump change

no errors shown in mes, i tried few other parts from my donor: coil packs, crank sensor, also disconnected lambda and it is same

a real mystery
 
i would say looking them pics (although they are tiny and hard to see) that your cam is not right and it should be clockwise a tooth. See pic below, appears to me you have it on the lowest mark making it a tooth out, might just be the angle and fact the pic is small though i suppose

Can't comment on the mark on gearbox side, i have never used it, only the mark on the crank pulley

here is pics from the manual
cam
2015-07-21 16.10.48.jpg

crank
2015-07-21 16.11.06.jpg
 
it started after 15sec of cranking
injector light was on for like 10sec
plugged it to mes and it showed lambda error
Disconecting lambda doesnt do anything

tries to stall , when car is in gear and i try to take off there is metal noise in engine, rough idle
got enough oil in engine
 
well starting from cold the lambda not working shouldn't make any difference as it will be in open-loop. How does it idle once its warmed up a bit? Sounds like you have tried all the usual susepcts - (have you tried some new ht leads) i would re-check your timing marks - only takes a moment to drop the lower pulley of to check the marks on the crank. After than you may as well look at this lambda fault although it really shouldn't affect the starting as i said.
 
well starting from cold the lambda not working shouldn't make any difference as it will be in open-loop. How does it idle once its warmed up a bit? Sounds like you have tried all the usual susepcts - (have you tried some new ht leads) i would re-check your timing marks - only takes a moment to drop the lower pulley of to check the marks on the crank. After than you may as well look at this lambda fault although it really shouldn't affect the starting as i said.

didnt try ht leads yet, as i bought new on 14.4.2015
ht leads affect starting?
didnt let the car to warm up to check idle, but it is rly eager to stall

for timing marks they are good as i checked them on my other mk1, and i got it same 0 mark on gearbox and aligned with camshaft, i did 2 turns on crank and everything aligned again
 
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well poor ht will cause no start or bad start and general bad running... As far as i can tell you have swapped out everything else on the ignition side so would at the very least look for flashing blue arc in the dark while starting/running. Or just sway them just to rule them out.

brb changing ht leads now

its same with other leads
 
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