Afternoon All,
I'm fitting a new cam belt, and I've got to the part where I need to remove the crank pulley. I can feel what appear to be three bolts in a circle, and one in the middle. Do I remove all of them?

I'm assuming the pulley is keyed so I can't refit it in the wrong position, or is that too much of an assumption?

What timing marks am I looking for?
TIA

There are no timing marks on this engine. The crankshaft and camshaft sprockets are not keyed to their shafts and can rotate if their centre bolts are loosened.

You need a kit of special tools which are available from Draper, Sealey etc. Occasionally suitable kits come up on eBay, just make sure that all the tools you need are present (I've described them below) as not all the Fiat T/belt Timing Tool Kits are suitable for the 1.4 Bravo.

The camshafts are locked in the correct position using 2 of the special tools.

The crankshaft is set using 2 plunger type tools inserted into No.3 & 4 spark plug holes - this engine timing is unusual in that the valve timing is set e.g. when changing a timing belt- by setting all 4 pistons at exactly the same height, not the more normal TDC (Top Dead Centre).

There's a locking tool to hold the camshaft sprocket when loosening the centre bolt, (not always necessary if just renewing a timing belt, ymmv). The camshaft sprocket is not keyed to the camshaft and will rotate if the centre bolt is loosened.

Plus a couple of other special tools in the kit, iirc one is bolted to the crank sprocket?(after the pulley is removed) in order to rotate it, the other is used to rotate the T/belt tensioner when setting the belt tension.

Re:- removing the crank pulley, just remove the 3 bolts. Don't touch the centre bolt, there's no need to if just changing the T/belt, plus the crank gear/sprocket is not keyed to the crank and will rotate if the centre bolt is loosened.

There's a very comprehensive guide to lots of different repair tasks incl. T/belt replacement available in the Downloads section (blue band at top of the page), click on downloads, scroll down to Bravo and select, scroll down to New Bravo eLEARN and open. Iirc, this is some kind of compressed file. (I'm useless with computers so had to get someone to open it and print off a hard copy for me )

Some people resort to making their own timing marks e.g. using Tippex and change the belt without using the kit of special tools. Some mark the old belt to the sprockets, remove the old belt, transfer the marks to the new belt, then fit the new belt so the marks align.
Some people use the trick of splitting the old timing belt in two sections lengthways, remove the outer 1/2 section, fit the new belt 1/2 onto the sprockets, remove the 2nd old section, push belt fully on, then change the tensioner etc.

I wouldn't risk any of these methods, even though lots of garages/ Mechanics do. (or so I've been told). If anything slips, you've no verifiable marks e.g. if you loosen the camshaft sprocket (it isn't keyed to the camshaft) it'll turn freely so any marks you've made to align the sprocket with the cam housing will be irrelevant.
The special tools are a lot cheaper than having to replace bent valves or worse....

Don't forget the water pump, (which is driven by the T/belt), it's usually changed at the same time as the belt to avoid any future problems.

Al.

Thanks for the comprehensive reply. I'm basically in the mire then... I didn't mention that I'm replacing a stripped belt, so the timing is going to be off anyway. I know this is an interference engine, so I'm taking a chance in the hope that there is no/minimal damage. I hadn't planned on replacing the water pump, although I know it goes against good practice (I'm an ex mechanic) as I don't want to spend unnecessarily if the engine is wrecked anyway. So as I say, I'm chancing it. I think I need to find a friendly mobile mechanic who has the correct kit, and get them to reset the timing. Thanks again - watch this space...

Hi F123C,
Just noticed in your reply that you mention camshafts, i.e., plural. Just to clarify, in case the procedure is different, this is a 1.4 90 petrol engine, sohc.


If the pistons are all set level, the camshaft obviously doesn't want to be rocking on valves 1 and 2 - so where should it be?

Just realised what I said, and now I can't see the edit button... Ignore the bit about sohc...

Hi unkeykane,

Sorry to hear about the stripped belt.
I was going to suggest setting the pistons to halfway down the bores, then turn the camshafts (by the belt pulley bolt - the inlet cam is gear driven from the exhaust cam at front of engine) and check the valve clearances as a quick check for bent valves, but I don't think this will work as this engine has hydraulic tappets.

You could do a cylinder leakage test if you have the means to inject compressed air into each cylinder in turn having turned the cams to close both valves in each cylinder in turn, then either see if the pressure gauge drops or just listen at the throttle body or exhaust pipe for leaking air.

As regards setting up the valve timing when things have slipped, in the absence of the correct tools, I'd try setting all pistons to the same height as accurately as possible using rods/screwdrivers (maybe attach some masking tape and mark a scale on it?) down no.3 & 4 spark plug holes. To set the camshafts, there's 2 blanking plugs (iirc they take a 10mm? allen key) in the cam housing - remove these and turn the cams while looking into the holes for the appearance of 2 cut-outs in the cams, align these as best as possible with the centres of the holes. Iirc the special locking tools are approx. 8mm? with a small flat, where they engage with the cut-outs in the cams, so you might be able to use some 8mm rod or bolts to centre the cut-outs in the cam housing holes. You might try removing the cam cover to better see what you're trying to align with on the cams.
This will set the camshafts. Then fit a new belt. If you're just seeing if the engine is still undamaged, you might be able to just ease the old belt off and fit the new belt without touching the tensioner.

If you check out www.lasertools.co.uk/product/5638 and click through the pics, you'll see what these special tools look like and what you're trying to emulate using rods/screwdrivers etc.

Given the new cost of the special tools, most people just have a garage do the job, plus have a guarantee (maybe ) in case things go wrong.
But as I said, sometimes the tool kits come up on eBay etc. Last time I did my timing belt renewal, I managed to find someone willing to hire me the tools.

P.S. the reason the cam sprocket/pulley freewheels on the camshaft when the centre bolt is loosened is to allow it to move when tensioning the belt without it trying to move the pistons or camshafts from their correct setting positions. You might not have to loosen the centre bolt if just fitting a new belt to check for any engine damage, ymmv.

Good luck, let us know how things work out. If you need any torque settings etc., just ask, I have a note of these somewhere. I was glad to hear you're an ex-Mechanic, I'm one too, so happy to help out.

Al.

unkeykane said:

Just realised what I said, and now I can't see the edit button... Ignore the bit about sohc...

Click to expand...

For some reason, on Fiat Forum, the edit button disappears a few (maybe 4?) hours after you've made a post.

Al.

unkeykane said:

Hi F123C,
Just noticed in your reply that you mention camshafts, i.e., plural. Just to clarify, in case the procedure is different, this is a 1.4 90 petrol engine, sohc.


If the pistons are all set level, the camshaft obviously doesn't want to be rocking on valves 1 and 2 - so where should it be?

Click to expand...

Easy to think that this engine is sohc when you remove the timing belt cover, but of course it's dohc, the (rear) inlet cam is gear driven from the (front) exhaust cam, visible if you remove the cam cover. (as you realised after posting).

I'm sorry I don't know which valves if any are being opened/closed/rocking when the pistons are all set level with each other.
Only info I have is the valve timing figures :-
Inlet opens 2* after tdc, closes 42* after bdc
Exhaust opens 34* before bdc, closes 2* before tdc.

^^ I've used the * symbol to indicate degrees.
^^Note that these figures are with the valve clearances set to 0.45mm (inlet and exhaust) for timing checking purposes. As this engine has hydraulic tappets, I don't know how you'd arrange to have these valve clearances before checking the valve timing. But maybe these figures might be of some help after you've fitted a new belt?

Best wishes,

Al.

F123C - again, thank you. I'll try this method and report back. I have found a mechanic who knows how to do it without the tools, but his wife has just had a baby so he's out of action for a bit... Incidentally, i've attached a pic which shows a mark on the crank sprocket, which happens to line up at TDC, with a small web on the front casting. Coincidence...?

Hi Al,
I'm a little confused here - I can only see one plug. I've had to remove the sprocket anyway to get access to the plug, and I've removed the small cover next to it but that has only exposed the end of the other camshaft. Would the second plug happen to be behind the first one? I've stuck a 10mm allen key in there and it's locking in to something...

F123C this is what I'm seeing in the hole. No movement of any sort. Am I in the wrong place?

Found them...

Well that's that well and truly stuffed...

unkeykane said:

Well that's that well and truly stuffed...

Click to expand...

I'm sorry to hear this ^^

How bad is the damage?
Did you remove the cyl. head?
If so, any pics?

If the damage is only to the valves/cyl. head, maybe you can source a s.hand head/engine? Remember this 1.4 engine was used in several other models apart from the Bravo, so possibly a cyl. head/engine from a different model could be used?

Commiserations,

Al.

Hi Al,

I haven't removed the head although I'm tempted to do so out of curiosity, but I can think of better things to do on a day off...
It's not even trying to fire so I'm guessing there is more than one bent valve/damaged piston. However, I've learnt a lot about this engine, and here are some observations:-
As you have pointed out, it's timed with pistons 3 and 4 level, however, it appears to make a difference which stroke each piston is on, but I can't for the life of me get my head around why. I timed it once, and I could turn the engine part way, then it locked up solid. Re-timing it by180 degrees freed it up. Am I missing something simple? :bang:

Regarding the camshaft cutouts (I eventually realised which plugs I was supposed to be removing... ) if the cutout on the front cam is visible, surely that means that the rear one must be in the correct position, so there should be no need to remove the rear plug? I mention this because in doing so, I managed to snap off the fuel pipe feed which resulted in a trip to the nearest scrapyard, who, fortunately, had a car in the yard which had the correct fuel rail. I also had to cut the fuel line off, and surgically insert a new section from the donor car

By the way, were you a Fiat mechanic, or have you picked up your knowledge of these cars along the way?

Tony P.

Some help:

aschiuta said:

Some help:

Click to expand...

Thank you, that's exactly the information I needed regarding crank position.

unkeykane said:

Hi Al,

I haven't removed the head although I'm tempted to do so out of curiosity, but I can think of better things to do on a day off...
It's not even trying to fire so I'm guessing there is more than one bent valve/damaged piston. However, I've learnt a lot about this engine, and here are some observations:-
As you have pointed out, it's timed with pistons 3 and 4 level, however, it appears to make a difference which stroke each piston is on, but I can't for the life of me get my head around why. I timed it once, and I could turn the engine part way, then it locked up solid. Re-timing it by180 degrees freed it up. Am I missing something simple? :bang:

Regarding the camshaft cutouts (I eventually realised which plugs I was supposed to be removing... ) if the cutout on the front cam is visible, surely that means that the rear one must be in the correct position, so there should be no need to remove the rear plug? I mention this because in doing so, I managed to snap off the fuel pipe feed which resulted in a trip to the nearest scrapyard, who, fortunately, had a car in the yard which had the correct fuel rail. I also had to cut the fuel line off, and surgically insert a new section from the donor car

By the way, were you a Fiat mechanic, or have you picked up your knowledge of these cars along the way?

Tony P.

Click to expand...

Hi Tony,

Have you got compression on all cylinder?
Have you got a spark on all cylinders?
If there's no compression on 1 or more cylinders, then obviously the cyl. head will have to be removed for investigation - I think it would be worth doing so, even just out of curiosity, plus you could then post pics as a cautionary tale for anyone who is thinking of delaying a routine t/belt change.

'Aschiuta' has very kindly posted the info I mentioned that can be found in the Downloads section at the top of the page (eLEARN, then scroll down to and select New Bravo), which probably answers your other questions. This info mentions the engine is timed with No.1 piston on the intake stroke - in your 1st attempt at timing the engine, maybe No.4 piston was on the way up rather than going down i.e. 180* from where it needed to be relative to the camshaft/s position (set using the cam locking tools).

Re:- only needing to lock one cam in position, as the other is gear driven from it, you're probably right if just changing a timing belt. But what about a situation where someone has also removed/refitted a camshaft/s (e.g. to work on the valves), how would you time the second cam?

As regards, snapping off the fuel line, that was unfortunate, good that you were able to find one in a scrapyard - maybe you could go back and buy the cylinder head? Just a thought

I served my apprenticeship back in the late '70's in a Fiat & Lancia Main Dealership, so am quite familiar with Fiat models of this era, but nothing later than the early '80's. Only reason I know a bit about the Bravo 1.4 90HP is that I have one (by the way the engine code for the non-turbo model is 192B2000).

Regards,

Al.

F123C said:

Hi Tony,

Have you got compression on all cylinder?
Have you got a spark on all cylinders?
If there's no compression on 1 or more cylinders, then obviously the cyl. head will have to be removed for investigation - I think it would be worth doing so, even just out of curiosity, plus you could then post pics as a cautionary tale for anyone who is thinking of delaying a routine t/belt change.

'Aschiuta' has very kindly posted the info I mentioned that can be found in the Downloads section at the top of the page (eLEARN, then scroll down to and select New Bravo), which probably answers your other questions. This info mentions the engine is timed with No.1 piston on the intake stroke - in your 1st attempt at timing the engine, maybe No.4 piston was on the way up rather than going down i.e. 180* from where it needed to be relative to the camshaft/s position (set using the cam locking tools).

Re:- only needing to lock one cam in position, as the other is gear driven from it, you're probably right if just changing a timing belt. But what about a situation where someone has also removed/refitted a camshaft/s (e.g. to work on the valves), how would you time the second cam?

As regards, snapping off the fuel line, that was unfortunate, good that you were able to find one in a scrapyard - maybe you could go back and buy the cylinder head? Just a thought

I served my apprenticeship back in the late '70's in a Fiat & Lancia Main Dealership, so am quite familiar with Fiat models of this era, but nothing later than the early '80's. Only reason I know a bit about the Bravo 1.4 90HP is that I have one (by the way the engine code for the non-turbo model is 192B2000).

Regards,

Al.

Click to expand...

Hi Al,
I don't have means for testing compression, but when turning the engine over, it sounds as though there is no resistance whatsoever. I've checked for a spark on one plug and that was ok - I don't really think that's the issue. I tried to post a short video clip but it won't allow mp4 files

You're right about the eLEARN manual. Had I dug a little deeper I would have come across it...

I'm still in two minds about removing the head, although I'm tempted, as my curiosity is nagging away at me.

Regarding apprenticeships, mine started in 1974 with Leyland, in the fine days of the Allegro, Maxi, Princess, Marina etc.

Thanks again for your invaluable help,

Tony P.

Hi, can you please share some info with the rest of us on how the stripped belt situation occurred? How old is the car/belt? How many miles?