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Discussion Starter #1
I currently have a broken 156 2.0TS on my drive and am stumped as to the problem.

When pulling away from traffic lights the power steering failed upon calling the AA it appears that the auxiliary belt has shredded itself and taken a chunk out of the tensioner pully. As soon as this happened the engine was turned off and now will not start. Prior to this the car did lose power on a couple of occasions with a loss of powered steering which I am putting down to the failing belt.

The garage that have looked at the car say that there is no compression in the two cylinders that they have tested and are asking obsence amounts of money to repair the engine. Both the cam belt and the balancer shaft belt and all tensioners look to be fully intact.

My only guess is that part of the aux belt has got into the cam/balance belt and affected the timing but cannot actally see how this has happened when the cam belt is covered.

Any help would be appreciated before I start to take it apart
 

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Was the engine running ok when you turned it off? If so I would seem unlikely to be a problem with the engine as such.

I would be concerned about the previous loss of power before. That would indicate the engine had some sort of problem, the power steering would stop when the engine stopped.

The auxilliary belt and cam belt can't interfere with each other so that would not be an issue.

Sounds like two different problems at the same time. Loss of compression on two cylinders sounds terminal so the second opinion is a must. But if the engine was running ok when you turned it off it should not have a compression problem. Is the garage cosher?
 

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A quite likely scenario is that it was the tensioner failing that took out the belt rather than the other way around. Anyway, regardless of that, it is entirely conceivable that a chunk of it could cause cam belt problems. Unfortunately they most definitely can interfere with each other.

If the timing has been put out by a piece of aux belt getting tangled into it for a moment then the lack of compression may be a sign of bent valves. Lack of compression does usually mean bent valves I`m afraid. (but not always - keep positive!)

As Alfapat says, the best, first option is to remove the cam belt cover and take a look. Check for missing/stripped teeth. Try to line up the timing to see if its out (if you know how) and progress from there.

You may be lucky and its something unconnected but it isn`t sounding good at the moment mate, sorry :(
 

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I would get a second opinion on the engine compression as it sounds too conincidental. I think it would be very unlikely that the auxilary belt has interfered with the cam/balancer belt as there is a plastic cover seperating them. (Cam and balance belts + their tensioners are enclosed). It may be that when you auixilary belt was failing the battery was not getting much charge hence the problem with the car not starting. Did the car turn over when you attempted to start?
The power steering would have then failed when the belt failed completely. I wouldn't mind betting it is the tensioner that has seized leading to these further problems. (it is quite exposed)
 

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Yes on the 2.0TS/JTS the cam & balance belts are enclosed as much as possible, although we are assuming that the lower cover is still in place and not missing...

BTW, on the 1.6 & 1.8, there is no lower cover so the aux belt & cam belt can very easily tangle if the aux belt comes off.
 

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Discussion Starter #7
I have taken the cambelt cover off and checked the timing which is definitely out (I assume all the marks should line up on the crank pulley and the exhaust cam etc which they do not).

Bits of the aux belt had wound around the bottom crank and then made their way across to the balance belt through the hole in the casing. It appears that it then allowed the belt to slip as it could not engage with the teeth on the pulley.

Chris I think you are correct that the aux tensioner failed and the belt then rubbed on the metal causing it to fail. It is one of my relatives cars and he did mention that it was making a strange noise on start up!!

The balancer belt now appears to be very loose (you can slide it off the pulleys with no trouble) how tense should it be? However the timing belt its self looks fine (no teeth missing) would just the balance belt slipping cause the timing to be that far out and bend the valves?
 

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The balance belt has nothing to do with the valve timing, the engine will run with the belt remove but obviously out of balance. It should however be tight.

It sounds like it was probably overdue a belt & tensioner change (ALL of them), or at least someone skimped and refitted the old aux belt.

Definitely time for the head to come off I think!
 

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Im don`t think there are many marks you can rely on unless the timing belt lines are all lining up by coincedence and then no 1 is tdc,, I think you just check that the camlobes on No 1 are facing to the rear on inlet along with tdc.
 

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Discussion Starter #10
Thanks - There is a white/yellow mark on the exhaust cam pulley and a small pointer fixed to the engine block, I was asuming that lining these two up would show when it was in the correct position. If not what is this marker for? Never mind I will have to take the cam cover off and check the camlobes or get a set of cam locks.
 

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you could check the valve clearances ,even thou they are hydraulic,the valve clearance will be alot greater if the valves are bent[over 30 thou clearance]
 

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Discussion Starter #12 (Edited)
It appears that in the run up to the belt failure the engine had been cutting out whilst driving if the revs dropped - fairly serious in my view as powered steering etc failed as you would expect - on an intermitant basis. If it helps this only appears to be within the first 10 to 15 mins of driving

Any ideas if this is connected?
 

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Cutting out is usually down to the throttle/ecu/maf/lamba sensor not belts.
 

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the marks on the camsprockets are there for lining up the belt which has three white lines on it , one of which lines up on crank gear pulley, the other on exhaust, can`t remember the third off hand,they are for reference when putting the belt on on initial timing of new belt , these marks move once the whole lot move one revolution but will line up after about 10 turns due to different ratios of sprockets.
 

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Discussion Starter #15
Cheers Alfapat - I shall wait until I get a chance to get the cam cover off and have a look at the timing I will let you know how I get on

Any ideas on the cutting out from reading other threads appears it might be the TDC sensor or the MAF sensor. Tended to cut out when slowing down to turn right or for traffic lights, would normally start again straight away afterwards.
 

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Discussion Starter #16
Compression tester purchased - I have compression on 2, 3, 4 but none on 1 (nearest cam belt). I would have thought that there would be no compression on at least one of the other cylinders as well.

Cam cover removed lobes on number one are facing the rear but not at right angles to the engine so it looks like the timing is slightly out.

If only a couple of valves are damaged is it worth getting the whole head rebuilt or is it an easy diy job
 

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Discussion Starter #17
Following the aux belt failure and subsequent cam belt slippage head has now been removed.

All the valves have hit the pistons!! especially the inlet ones which have made a significant dent in the pistons about 4-5mm deep the exhaust ones have only just touched the pistons. Strangely I still have compression on 3 of the cylinders so assume the damage was gradual rather than sudden (which would have happened if the belt snapped) as rather than bend the valves the pistons have been dented.

I assume as the timing belt do not break but slipped this allowed more damage to occur.

Now the $64,000 question - is it worth repairing it with such significant piston impact(however the bores themselves are not damaged)? What other damage could have occurred?
 

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you will find the pistons are not dented,but rather the pistons are made like that.best bet get a recon head depending how damaged the head is.The hydraulic tappets/buckets may be damaged.also the remove the valves and check the guides for cracks from the bottom looking upwards.If guides ok may be worth risking the tappets and just buy new valves and do up your old head. depending if money is tight.............MP...........
 
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