Northern Auto Tech - ECU and Blue & Me Repairs

500 Sons dilemma

Currently reading:
500 Sons dilemma

T

tjaski

New member
Joined
Jun 9, 2018
Messages
10
Points
4
Hello All,
Need some help with a Fiat 500 1.4 16v sport.
Having come home from hols, have found my son and his mates have done a bit of "maintenance" to his car. They have decided to change the cam belt, and oil. Oil and filter, plus plugs went fine, they have the covers stripped of and replaced the belt using the "tipex" method which they found on youtube.
Good thing is they havent started it!!!
They have rotated the crank by hand and now the "tipex" marks dont line up.
So its up to DAD!!, so anyone can tell me how to line everything up please??
 
ah timing a valver... seems a nightmare that it doesnt have marks but its not that hard really...

I highly recommend some timing tools, these cheapy ones is what i have https://www.ebay.co.uk/itm/Engine-T...avo-Brava-1-2-16v-Twincam-Petrol/281941623655

But it is doable without if you can't wait.

1. take spark plugs out, just cylinder 1 & 2 but if you take all 4 out it'll be easier to turn the engine.
2. find 2 long thin things, they need to fit down the spark plug hole and they need to be the same length as each other, EXACTLY SAME LENGTH!! Put on in cylinder 1 and the other in cylinder 2.
3. Turn engine by hand until both long things are completely level - this engine is timed with the pistons all level and not at TDC...
4. on front of the head there is a plug, i've not got a pic to hand i'm afraid, but you unscrew that and if its timed up right you should see a slot in the camshaft. From memory a 11mm allen key will fit perfectly in that slot but having had the tools for years now it might be 10mm or 12mm, it needs to fit snug so the cam cant move at all.
5. slacken off the bolt holding the cam pulley on, just enough that the pulley will spin - its not got a woodruff key or anything so it can spin freely on the cam.
6. making sure you've not disturbed the bottom end (i.e. the markers you've put in cylinders are still perfectly level) put the belt on.
7. so now you have the cylinder level, the cam locked and the belt on you can tension it - you want to twist the tensioner so the 2 little lines on it line up, it tends to spring back a tiny bit once to nip it up so go just past the mark, tighten the tensioner up and check the lines, adjust if necessary. This is easy cause the top pulley is free to rotate atm without moving the camshaft itself.
8. Once you happy with tensioner, tighten up the bolt on the top pulley to lock it back to the camshaft. And you are timed up now.

9. remove whatever you stuck through the hole in the head to lock the camshaft and turn engine over several complete rotations by hand, then get your piston level indicators perfectly level again, poke the thing back in the camshaft to check its still in right place. Hopefully it is, i think from memory they can be level and your on the wrong stroke so slot in cam shaft isnt visible... Its been a while but from memory you want piston 1 going up and piston 2 on its way down but not 100% sure without looking it up. Assuming everything is still lined up just refitt the cam lock screw thing and put plugs and everything back in etc and your done. Its actually a really easy engine to time once you done it the first time.

If you can wait for the tools its much less scary as the cam locker is properly tight fit and there is not even the minutest bit of slop when cams locked. The process is exactly the same just you have proper tools rather than winging it. ;)
 
This post contains affiliate links which may earn a commission at no additional cost to you.
Brill Thanks for that, will try in the morning....
Suppose at least he had the good sense not to try to start it!!! and at least he had a go..
 
You said, "on front of the head there is a plug" what do you mean as the front, sorry sounds a odd question, front radiator side, or nearside bulkhead?
 
tjaski said:
Hello All,
Need some help with a Fiat 500 1.4 16v sport.
Having come home from hols, have found my son and his mates have done a bit of "maintenance" to his car. They have decided to change the cam belt, and oil. Oil and filter, plus plugs went fine, they have the covers stripped of and replaced the belt using the "tipex" method which they found on youtube.
Good thing is they havent started it!!!
They have rotated the crank by hand and now the "tipex" marks dont line up.
So its up to DAD!!, so anyone can tell me how to line everything up please??
Click to expand...
Yes, I agree with Veresecrazy. Don't panic! If your lads have marked everything up correctly with the tippex in the first place you should be ok. I would congratulate them on their initiative and hope they enjoyed themselves. Just a pity it wasn't the old banger that most of us first learned how to round off nuts and bolts on!

If we think about this for a minute. If you make a mark on each of the cam and crank sprockets and a corresponding mark on the cylinder head opposite each cam sprocket and on the engine block opposite the crank sprocket then you will find that the crank marks will line up every complete revolution of the crankshaft and the cam pulleys will line up every two revolutions of the crank. That's how 4 stroke engines work! However if you make a mark on each sprocket and opposite those marks a corresponding mark on the belt itself you will find that, after two revolutions of the engine, the marks on the belt will not return to align with the marks on the sprockets. At least I've never found that to be the case. For that to happen the total number of teeth on the belt would have to equal the number of teeth on one of the cam sprockets (or twice the number of teeth on the crank sprocket) - A most unlikely scenario!

I suppose, if you knew for absolute sure exactly how many revs they turned it over by, you could wind it back by that number of revs and see if the marks line up. But it is considered bad practice to turn engines backwards as it can cause timing slips etc. I would always avoid doing so myself. Personally I would still have a nagging doubt in my mind not having myself made the original marks in the first place!

If I found myself in your situation I would buy a kit of engine locking tools on eBay, other sellers are available!, and use it to double check it all. I bought a Neilsen branded set for our 1.2 Panda, which will also work on my boy's 1.4 8 valve Punto. It was in the £40 range. Cheap enough for the peace of mind it gives.

If you decide to do none of this and are wondering if any damage has been done you could check by removing all the spark plugs (so there is no compression effect on the engine) and very gently, with a spanner or socket on the crankshaft sprocket bolt, turn the engine through two full revolutions. You should easily feel if a piston is in contact with a valve as the crank will come to a sudden stop. If you are going to do this remember to turn the crankshaft very slowly as the flywheel will add a lot of force if you turn it quickly and it could still bend a valve for you!

If you are handy with the spanners there is a more scientific way you could check. I'm assuming the lads didn't remove the cam cover? Well if you do then you can observe the camshafts themselves. Now, gently again, and with the plugs removed, you are going to turn the crankshaft with a rod of some sort inserted in the No1 plug hole. Helps to have two people doing this. You will be able to feel as the piston comes to the top of it's stroke and that is where you want to stop (this is called Top Dead Centre) For the purposes of this excercise you don't need to be absolutely spot on but the closer you can get to TDC the better. Now look at the cam lobes. With the piston at TDC No1 cylinder will be on either the top of it's compression stroke or exhaust stroke. It's going to be either one or the other so let's say it's on the top of it's compression stroke. The inlet and exhaust valves should be closed (that is to say the cam lobes should be pointing towards the sky. They won't be entirely perpendicular if you compare the inlets to the exhausts they should look like a mirror image of each other. If one set of lobes is pointing up in the air and the other is at, say 45°, then, oh boy, you've got a problem and don't turn the crank! If you look at the same time at No4 cylinder it has to be the opposite of whatever No1 is. So if No1 is on compression No4 will be on TDC exhaust and all valves should be depressed (open) because the exhausts are closing and the inlets are starting to open. (Called being in "overlap") So again the inlet lobe positions should be a mirror image of the exhausts. It should all look nice and symmetrical! You will probably not be able to say the timing is spot on by doing this but you will probably notice if the timing is more than about a tooth out of sync.

Hope this is helpful. Best advice though is the old saying, if in doubt DON'T! The don't bit refers to using the starter motor.
Wish you the best of luck with it. On the brighter side, there are lots of YouTube videos on how to do this and the ones I've seen have all been pretty good, chances are the guys probably did good!

Regards
Jock
 
Ok just been out to look and between the cams, and slightly below the two, obviously the left cam is blanked off and the right cam has the sprocket, there is a allen keyed anodised in colour, plug. set flush in the head, Is that it??
 
Thanks for that, i do have a bit of experience as i did the cam belts on my diesel vw and ford galaxy, but i did have something to go by like timing marks on the castings. So this is what i was looking for on the fiat. But i amused that the got the tipex right, rotated the crank a few times and the tipex doesn't line up, so after talking to them, yep it didn't line up so the slacked the tensioner and moved the cam sprocket to suit and yet after how many rotations i don't know still doesn't line up so i need to assume i am starting from scratch. As if i have put a new head on...
 
Pugglt Auld Jock said:
Yes, I agree with Veresecrazy. Don't panic! If your lads have marked everything up correctly with the tippex in the first place you should be ok. I would congratulate them on their initiative and hope they enjoyed themselves. Just a pity it wasn't the old banger that most of us first learned how to round off nuts and bolts on!

If we think about this for a minute. If you make a mark on each of the cam and crank sprockets and a corresponding mark on the cylinder head opposite each cam sprocket and on the engine block opposite the crank sprocket then you will find that the crank marks will line up every complete revolution of the crankshaft and the cam pulleys will line up every two revolutions of the crank. That's how 4 stroke engines work! However if you make a mark on each sprocket and opposite those marks a corresponding mark on the belt itself you will find that, after two revolutions of the engine, the marks on the belt will not return to align with the marks on the sprockets. At least I've never found that to be the case. For that to happen the total number of teeth on the belt would have to equal the number of teeth on one of the cam sprockets (or twice the number of teeth on the crank sprocket) - A most unlikely scenario!

I suppose, if you knew for absolute sure exactly how many revs they turned it over by, you could wind it back by that number of revs and see if the marks line up. But it is considered bad practice to turn engines backwards as it can cause timing slips etc. I would always avoid doing so myself. Personally I would still have a nagging doubt in my mind not having myself made the original marks in the first place!

If I found myself in your situation I would buy a kit of engine locking tools on eBay, other sellers are available!, and use it to double check it all. I bought a Neilsen branded set for our 1.2 Panda, which will also work on my boy's 1.4 8 valve Punto. It was in the £40 range. Cheap enough for the peace of mind it gives.

If you decide to do none of this and are wondering if any damage has been done you could check by removing all the spark plugs (so there is no compression effect on the engine) and very gently, with a spanner or socket on the crankshaft sprocket bolt, turn the engine through two full revolutions. You should easily feel if a piston is in contact with a valve as the crank will come to a sudden stop. If you are going to do this remember to turn the crankshaft very slowly as the flywheel will add a lot of force if you turn it quickly and it could still bend a valve for you!

If you are handy with the spanners there is a more scientific way you could check. I'm assuming the lads didn't remove the cam cover? Well if you do then you can observe the camshafts themselves. Now, gently again, and with the plugs removed, you are going to turn the crankshaft with a rod of some sort inserted in the No1 plug hole. Helps to have two people doing this. You will be able to feel as the piston comes to the top of it's stroke and that is where you want to stop (this is called Top Dead Centre) For the purposes of this excercise you don't need to be absolutely spot on but the closer you can get to TDC the better. Now look at the cam lobes. With the piston at TDC No1 cylinder will be on either the top of it's compression stroke or exhaust stroke. It's going to be either one or the other so let's say it's on the top of it's compression stroke. The inlet and exhaust valves should be closed (that is to say the cam lobes should be pointing towards the sky. They won't be entirely perpendicular if you compare the inlets to the exhausts they should look like a mirror image of each other. If one set of lobes is pointing up in the air and the other is at, say 45°, then, oh boy, you've got a problem and don't turn the crank! If you look at the same time at No4 cylinder it has to be the opposite of whatever No1 is. So if No1 is on compression No4 will be on TDC exhaust and all valves should be depressed (open) because the exhausts are closing and the inlets are starting to open. (Called being in "overlap") So again the inlet lobe positions should be a mirror image of the exhausts. It should all look nice and symmetrical! You will probably not be able to say the timing is spot on by doing this but you will probably notice if the timing is more than about a tooth out of sync.

Hope this is helpful. Best advice though is the old saying, if in doubt DON'T! The don't bit refers to using the starter motor.
Wish you the best of luck with it. On the brighter side, there are lots of YouTube videos on how to do this and the ones I've seen have all been pretty good, chances are the guys probably did good!

Regards
Jock
Click to expand...
I was looking for parts for my boy's Punto on eBay last night and came across timing tool ads. I'm not that familiar with the 16 valve engine, as you might have gathered from the rather generic advice I gave earlier! The timing tools for the 16v are half the price of those for our 8 valvers which makes the decision a no brainer. Just buy a set of timing tools and then all uncertainty will be removed!
 
tjaski said:
Thanks for that, i do have a bit of experience as i did the cam belts on my diesel vw and ford galaxy, but i did have something to go by like timing marks on the castings. So this is what i was looking for on the fiat. But i amused that the got the tipex right, rotated the crank a few times and the tipex doesn't line up, so after talking to them, yep it didn't line up so the slacked the tensioner and moved the cam sprocket to suit and yet after how many rotations i don't know still doesn't line up so i need to assume i am starting from scratch. As if i have put a new head on...
Click to expand...
Just rereading the thread and I think what you said here is that the tensioner was slackened and a readjustment made? If you altered the positioning of the belt relative to the sprocket teeth then you definitely need the timing tools!

Also, on rereading my post earlier, I just realised the cams live in the one piece cam cover on this engine. So, although the advice given in the paragraph starting "if you are handy with the spanners" is generically correct, it's going to be a bit difficult to do when you can't see the cams once installed on the head! What a prat! Sorry folks.
 
Thanks to everyone for the replies, good to know that you all to help and not get bogged down with, "you shouldn't be doing that " mindset, taking blu73 advise and mixing it with varesecrazy, and looking the Punto pages by jonnyaykroyd all went well. I have a set of 4 dial guages, inserted them into all plug holes and rotated, and took notes. Found the Allen plug on the exhaust cam and as a mix of instructions found where everything was positioned. Set out using my own tipex marks and found out the lads, were one tooth out, to their credit they didn't ring the starter motor, just hand crank.
I set everything, had a cup of tea, looked at my notes then went through everything again. All good, assembled everything,checked oil level, changed plugs, as I found original ones still in car at 83k miles plug gap was 3mm. and I fired it up, fired up straight away.
So thanks again.
 
You must log in or register to reply here.

Similar threads

J
TC dilemma
Replies
6
Views
482
s130
s130
G
Ciao sono un nuovo membro del forum
Replies
1
Views
178
Iggy64
I
S
Sonny fiat 290
Replies
0
Views
300
sonny91be
S
AutaB
500 iPhone dilemma
Replies
6
Views
934
jrkitching
J
R
Stuck in a dilemma between Fiat Linea TJET and Jeep Compass
Replies
0
Views
407
ramganap
R
Back
Top