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My Progress & Timing Question

5K views 97 replies 7 participants last post by  Smaky 
#1 ·
Started replacing my timing belt today :eek:

i have set the timing as best i can, but notice the lobes on the inlet cam appear to be out (facing directly up on the 3rd & 4th lobe) having not recieved my cam blocks yet, i was reffering to pictures of the blocks and it appears to slope back slightly. I have a feeling even before putting the cam blocks on the timing is out a mile.

See pics and tell me what you think

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#37 ·
Thanks forall your help from the start i really do appreciate it.

I tried a large lever behind it, so i was levering & hammering at the same time and still nothing. What if i take the bolt out in the middle and remove both the t/belt crank pulley and the b/belt pulley and inspect from there. Would that work. I would need a thin socket by the looks of it.
 
#38 ·
I tried a large lever behind it, so i was levering & hammering at the same time and still nothing. What if i take the bolt out in the middle and remove both the t/belt crank pulley and the b/belt pulley and inspect from there. Would that work. I would need a thin socket by the looks of it.
I wouldn't even attempt to remove that bolt unless you have no other available option. That bolt goes directly into the end of the crankshaft and is done up to ~360Nm of torque so getting it out is very difficult without first locking the flywheel otherwise the crank will just turn with the force you need to use on the bolt. Then tightening it back up again to the correct torque poses a problem because DIY torque wrenches can't handle anywhere near that sort of torque. You need a professional torque wrench and ones that can handle that sort of torque cost >= £100 :eek:

I would try the localised heat option I suggested first and see how that goes.
 
#39 ·
:mad: Heat did not work.

With damaged threads on the idler plate and this i think the previous mechanic needs shot :lol:

I am going to fabricate a bracket that will bolt to the pulley with a large bolt in the centre to tighten thus pulling the B/belt pulley in the oppsoite direction, if you know what i mean.
 
#40 ·
:mad: Heat did not work.

With damaged threads on the idler plate and this i think the previous mechanic needs shot :lol:
It does sound like the previous belt change was well and truly bodged :tut:

There is definately something amiss because there is no way that pulley shouldn't just fall off with the two bolts removed and a small amount of gentle coaxing. There is clearly something holding it it place which shouldn't be there :rolleyes:

I am going to fabricate a bracket that will bolt to the pulley with a large bolt in the centre to tighten thus pulling the B/belt pulley in the oppsoite direction, if you know what i mean.
Yep...like a bearing puller. I was going to suggest one of those as another possible option but if you have the means to fabricate something similar yourself then it will obviously save on the cost of having to go and buy one.
 
#41 · (Edited)
:thumbs: Finally she gave in ;)

Used a slide hammer taken more than 5 hits to get it off (i have had more bother with this, than a siezed old brake drum i removed from a ford), however :( there was some sort of adhesive on the face as it decided to take part of the crank pulley with it (on the edge) turned the b/belt pulley round and seen the missing bit stuck to the b/belt pulley. I dont think it will effect the belt, just a bit concerned as it has a sharp edge. I might file it down, i think the new b/belt tensioner will keep the belt in place.....tell me what you think.

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#42 ·
I have never in my life seen such a bodged job of a cambelt change, i am shocked and for reference the b/belt pulleyhad a crack in it prior to me hitting it, with all the force required the weak bit gave in. I will get there in the end :)
 
#43 ·
I think i can see what the last owner has done, because i would not imagine a mechanic doing such a thing.

It appears that he has tightened the b/belt pulley and injected some araldite at the back :confused: I think the crack on the `1st pulley was due to him hammering on. as a result i have the lip cracked off the crank pulley because of the bond between the pulleys. The crack was small on the b/belt pulley,but gave in when i was trying to hammer it off. i was not bothered though as it needed replaced anyway.

Anyway thanks for all the help GE....will need to send you bottle of whisky :lol:
 
#44 ·
Hmmm...that cam belt crank pulley doesn't look good. I'm not sure what I would do about it to be honest. Complete replacement would be the best option but then you have to deal with getting that bolt out and back in again as previously mentioned.

You should certainly file/grind any sharp or rough edges off but I'm not sure if there would still be a chance that the belt could get caught up on that lip as it's going round.

Might be worth speaking to smaky when he's back and seeing if he has the special tool to lock the flywheel and a meaty torque wrench that can handle >= 360Nm. If he does then I would recommend just replacing that pulley completely and borrowing the tools from him, or better still getting him to actually help you do it.



P.S. I'll drop by and pick up the whiskey when I'm next up in Scotland...half my relatives live in Aberdeen :D
 
#46 ·
P.S. I'll drop by and pick up the whiskey when I'm next up in Scotland...half my relatives live in Aberdeen :D
:thumbs: Anytime, visit scotland on the next AO Run ;)

Think i will try the epoxy, tried it on other steel and had to hammer it off again so it's more than strong enough. Looking at the marks on the pulley the belt does not come into contact with the side so i may get away with. With regards to the balance of the puley i dont think it will be that bad with a small bit of resin holding it.
 
#47 ·
You've had more than you're share of bad luck with this belt change, it's a shame the monkey before you wasn't the one to suffer doing it a second time around.

That crank pulley bolt is most likely left hand threaded, so watch out for that (check the manuals first). I would change it, it looks too near the height of the teeth. Whilst the cam pulleys should ensure it runs straight and true it hasn't got to slip much to jump the belt off. Then you'll be able to use your belt changing experiences to do it all again as you take the cylinder head off to replace the valves.

Good luck. Best way to remove the bolt is put it in gear , have someone sit on the brakes - iirc there is no easy way of locking the flywheel on the engine. As GE says, you need a torque wrench big enough.
 
#49 ·
#51 ·
According to the workshop manual there's actually a special tool that Alfa use to lock the flywheel for removal of that bolt, however I've never actually removed the bottom cover of the bell housing or had to lock the flywheel myself so I'm can't say what the exact setup is or how it bolts on. You would need to take a look yourself...

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There is also an alternative way to do it using a different tool that actually bolts to the pulley and then is anchored to another part of the engine block...

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As AJ already mentioned, the thread on the bolt is left-handed.
 
#52 ·
You can't see much with the fly wheel cover off, I can't think where it would lock to, I guess something on the bellhousing? Which is probalby alloy, so go careful or the way your luck is going you'll be looking for a new bellhousing as well! I'd guess it locks on the ring gear and against the casing rather than through the flywheel onto the block.

That counter torque tool looks quite useful if you can construct something that bolts onto the face of the pulley.
 
#53 ·
Right, thanks guys. I will make something with pins to match the crank pulley, 2 holes for the bolts and 1 large centre hole. will have the bracket bolt on to the block somewhere (maybe use the 2 holes used for the tensioner plate). Will then do what AJ suggested with putting it in gear and firly applying brakes then use a large 3/4 inch breaker bar for the bolt.

That should get it, living on a farm has it's uses so i can get a large torque wrench for tightening.
 
#55 ·
:) I finally removed the crank pulley. The brakes were not holding with the strength required. So i used my variator tool to hold the crank, got the wife to hold the brake and off it came not a problem here is pics

Have sent Ned at autolusso the pics and they are going to replace the parts for me. :)

There is light at the end of the tunnel now, hopefully nothing else was bodged up.

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This is the variator tool that fits perfect on the crank pulley

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#56 ·
Back again with a quick question, as i am aware the white marks on the new belt line up with the notch on the ex cam sprocket and the notch on the crank pulley. When i line up the mark on the exhaust pulley the other white mark sits half way between the idler pulley and the crank. Does this indicate that i may have the wrong belt.
 
#57 ·
The white marks don't nessesarily mean you have the wrong belt, as some belts don't even have white marks.

Have you got the old belt? As the easiest way to check would be to lay them side to side and see if they are the same length. They should have the same number of teeth as well.

On the timing belt changes I have done I have ignored the marks on the belts, and just relied on the cam locks, and the white mark on the auxillary belt pulley to eset no1 piston to TDC.

Once the engine has been turned over the marks on the belt will no longer line up anyway, but the lower pulley mark should always line up with the cam locks fitted.
 
#58 ·
The problem i am having is that when the crank is at TDC, I run the belt from the crank to the ex sprocket and it will not fit the teeth of the sprocket. The belt will only succesfully fit the teeth when the crank is either left or right of the tdc mark. It appears the exhaust sprocket is out half a tooth....but i have not adjusted it. :confused:
 
#59 ·
You will need to slacken the exhaust pulley to allow the marks to line up. Even if you havent edjusted it there is a good chance that it will be out in relation to the lower pulley. I am not totally sure why this happens, but it may be due to it not being set correctly before you started, or due to a slight amount of stretch in the old belt.
 
#60 ·
Thanks simon... wow this cars turning out to be a pain. got everything timed and tensioned, i used the tensioning tool and the pin sits way past the pin, but i presume after a few revolutions the tension will get redone. But there seems to be alot of resistance when i started turning the crank as 1 is starting its exhaust stroke is this normal, i just left it for now untill i can get some verification about the resistance.

Thanks for all the help
 
#62 ·
But there seems to be alot of resistance when i started turning the crank as 1 is starting its exhaust stroke is this normal, i just left it for now untill i can get some verification about the resistance.
There WILL be a lot of resistance as the cams are pressing on the valve springs because they are very strong (double springs are used). The best way to turn the engine over by hand if you're not already doing it this way is to put the car into 5th gear, put the drivers side wheel back on loosely with a couple of bolts and turn the engine over by rotating the wheel (make sure the passenger side wheel is on the floor). It's much easier doing it this way although you will still feel some 'notchiness' as you turn the wheel as each set of valves are pressed open in turn. Obviously make sure the spark plugs are out while doing this as then you aren't fighting against and compression.
 
#61 ·
There will be a lot of resistance when turning the crank with the spark plugs in, as when cylinder one is on its exhaust stroke, number 4 will be on its compression stroke. If you have the timing wrong and the pistons are touching the valves it will come to a dead stop..

I am not sure about the tensioner though, the way I have checked mine is after turning the engine by hand, is to replace the cam cover and start the engine.
Make sure you keep fingers away, if you look at the pointer on the tensioner it should hover over the hole.

You won't have the other belts on at this time, so the charging warning lamp will be on.
 
#63 ·
All plugs have been out from the start, is it ok for the tensioner pointer to be sitting higer for now (Before the 2 Revolutions) does the pointer start pointing to the pin once this is done.....i dont want to put toomuch strain on the belt.
 
#64 ·
Here is the pics of the tensioner, the pin seems to be sitting high and after a number of revolutions still sits high. Is this too tight for the belt as i have seen that it should sit at the pin. If i slacken any more the run between the cams seem to slacken too much. Should i stop fussing and put it back together before i find more problems :lol: .
 

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#65 ·
That's too tight. After everything settles following a few revolutions of the engine, while the engine is turning the pointer should hover around the hole in the bracket. Are you turning the engine over by hand or on the starter motor? Doing so on the starter motor gives you a more realistic view of what is going on when the engine turns at speed. Get your wife to hold the key at the starter motor position while you see what's going on with the rotating belts and tensioners.
 
#66 ·
Was turning with starter....and its way too tight and that was me using an idiot proof tensioning tool. I think because i had to loosen the exhaust cam pulley and with the adjustment in the inlet cam i have pulled the belts too tight along the cams and in turn has put more tension on the tensioner....I think

I wish i had not started this, but truth of the matter i dont think there is any garage local that specialise in alfas, its just been one problem after another....i have the box of matches waiting :lol: .

I really appreciate the help you guys have given.

One thing i have noticed is that the inlet lobe that sits in the block has too much play for my liking the inlet cam will not settle in the middle of the cam block, although it does fit in the lobe it is resting on the edge . I dont think there will be a problem with this as the lobe is still inside the block. The exhaust lobe sits perfectly central to the block.
 
#67 ·
Was turning with starter....and its way too tight and that was me using an idiot proof tensioning tool. I think because i had to loosen the exhaust cam pulley and with the adjustment in the inlet cam i have pulled the belts too tight along the cams and in turn has put more tension on the tensioner....I think
Not sure how you've done the loosening and tightening of the cam pulleys but they way it should be done is that you loosen both pulleys then fit and fully tension the cam belt. Only then do you tighten the bolts in the two cam pulleys (4 bolts on the inlet one first then the single bolt on the exhaust one next). If you do it this way you shouldn't be able to get it wrong.

One thing i have noticed is that the inlet lobe that sits in the block has too much play for my liking the inlet cam will not settle in the middle of the cam block, although it does fit in the lobe it is resting on the edge . I dont think there will be a problem with this as the lobe is still inside the block. The exhaust lobe sits perfectly central to the block.
It's been a while since I last used the cam locking blocks on my engine but I'm sure the inlet cam is sprung from the force on two of the lobes by their respective valve springs. This means that as long as the lobe cut-out in the locking blocks has been machined correctly then you won't have an issue as the lobe will be sprung against one side of the cut-out so the inlet cam will be held in the correct position.

Out of interest, where did you get your cam locking blocks from (i.e. were they from a specialist / dealer)?
 
#68 ·
I got a loan of the blocks from the place i got the car (GTA Car sales) got the tensioning tools.

Maybe i should ask who the previous owner is so i can give him a good head bashing for making my first alfa belt change so fecking long and costly.

Never mind nearly done, at least its not been bodged together this time.
 
#69 ·
Maybe i should ask who the previous owner is so i can give him a good head bashing for making my first alfa belt change so fecking long and costly.
Package up all the broken parts and send them to him in the post...after gluing them back together with pritt stick first :D
 
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