147 GTA Problem: Motor Control System Failure

[Craig_m67]

Was just reading the UK site on this subject, interesting that the v6 cam belt change frequency is different round the world and by model (2.5/3.0/3.2). I wonder if this is alfa planning for different markets/conditions or (ateco?) alfa australia just gouging.

In anycase i always err on the side of safety and replace anything and everything preventative maintenance wise in the critical path when in doubt given labor is usually the most expensive bit if your not doing it yourself

Not sure (in my mind) that inspection includes the necessity to remove the belts. Cant the belts be visually checked for wear, imperfections and/or noisy bearings/tensioners by just removing the plastic cam covers?

[colcol]

The belts have to be taken off to inspect the teeth for cracks and the belt drying out, most belts look ok from the outside because the outside does not do any work and the tensioners, apart from looking at a rough finish on the pulley and obvious signs of a leak, they need to be taken off and checked for freeplay and rough running, and while it is all off you might as well put new parts on it as the labour bill is going to be the same, Colin.

[wankski]

I would love to see a chain conversion kit for these engines. This was never a problem with my 30 year old 105 series.

that, will never happen. chain systems are internal, lubed by the engine oil... chains don't 'stretch' the roller balls and links wear causing overall elongation over 100+ links... the biggest reason for wear is debris and particulate ingestion by the roller ball, causing internal grinding and play b/w the ball and links...

so, as you can see, and external 'dry' system would not work very well for long...

as colcol mentioned... belts are fine, but belt systems on interference motors is a bit rubbish... really, alfa could have made pocketed pistons and this whole discussion would be moot.

[L4OMEO]

On one of my Mercedes I had once a chain jump a couple of teeth. It happened on start-up, I shut it down immediately and managed to avoid bending valves, but it still cost $3500 to repair the damage. Yes I'd prefer chains over belts, but chains aren't immune from problems either.

BTW changing the cambelt on out Tarago costs an eye-watering $290 ....

Rory

[colcol]

The closer you run the pistons to the valves the more compression, the more power you get, move them away and you lose power, putting cutouts in the pistons would give more clearance for valve to piston, but you would lose power, just change the belts when you should and there will be no need for this discussion, also chain drives have a lot more noise vibration and harshness, but you don't have to change them till they skip a sprocket or they break, Colin.

[L4OMEO]

just change the belts when you should and there will be no need for this discussion  ...

I doubt there would be any discussion if it wasn't such an expensive exercise.

[colcol]

Yes, but they are an Alfa Romeo, you should know that they are not going to be as cheap to run as a Hyundai Getz, when they were new they were say $50,000, now they are worth half of that, they don't cost half as much to run as they did new, if you don't want to change the belts, fine just keep driving until it goes bang and then moan about the high price of reconditioned engines, Colin.

[bix]

I would love to see a chain conversion kit for these engines. This was never a problem with my 30 year old 105 series.

that, will never happen. chain systems are internal, lubed by the engine oil... chains don't 'stretch' the roller balls and links wear causing overall elongation over 100+ links... the biggest reason for wear is debris and particulate ingestion by the roller ball, causing internal grinding and play b/w the ball and links...

so, as you can see, and external 'dry' system would not work very well for long...

as colcol mentioned... belts are fine, but belt systems on interference motors is a bit rubbish... really, alfa could have made pocketed pistons and this whole discussion would be moot.

Yes that's a good point Wankski. I guess the chains in the 105 are lubed by the engine oil which would be a challenge if replacing a belt system with a chain in a modern engine.

[bix]

Was just reading the UK site on this subject, interesting that the v6 cam belt change frequency is different round the world and by model (2.5/3.0/3.2). I wonder if this is alfa planning for different markets/conditions or (ateco?) alfa australia just gouging.

In anycase i always err on the side of safety and replace anything and everything preventative maintenance wise in the critical path when in doubt given labor is usually the most expensive bit if your not doing it yourself

Not sure (in my mind) that inspection includes the necessity to remove the belts. Cant the belts be visually checked for wear, imperfections and/or noisy bearings/tensioners by just removing the plastic cam covers?

My 156 manual actually recommends changing the belts more frequently if the car lives in harsher climates. I suspect the cold weather may degrade the rubber more readily.
Hang on, doesn't that mean that living in a mild climate such as Oz, I can stretch my belt change for another couple of years??? - I personally don't think it would be worth the psychological stress worrying if the belt was going to break or not. If anything is to go wrong with the car it will always happen when the wife is driving alone in some remote parts...

[colcol]

The hot temperatures in Australia dry the belts out and the dust, which engineers say is only found in Australia wear the belts, they have their sharp edges ground away by the dust, which means the sharp edges no longer contact, and the radiused edges are more prone to slipping off the cogs, the cold temperatures were the achilles heel of the early twin sparks in freezing climates as the PLASTIC belt tensioners would shatter as they were brittle and the cam belt would go loose destroying your engine, Colin.

[L4OMEO]

if you don't want to change the belts, fine just keep driving until it goes bang and then moan about the high price of reconditioned engines, Colin.

I never said I was not going to change the belts then moan about a blown engine Colin. I agree with all the technical points you've made here, but I hope you agree that, regardless of them original price of the vehicle, these days the cost of a cambelt change is a significant percentage of the vehicle's current value. Again, hence the discussion.

[colcol]

Totally agree, and you will reach a stage when it just won't be worth changing the belts on the V-6 as the cost of a belt change, up to $2500, will exceed the price of the car, you can't blame the mechanics for the high price of the belt change, its just a lot of work to change it, and if possible have a look at one of these belts and see and feel the belts and think about what a great job they do, there is no right or wrong answer to this question, if you don't like rubber cam belts, get a 159 with a benzina 4 or V-6, they are a chain drive, Colin.

[bix]

That's a good point Colin. There is actually no programmed maintenance schedule to replace the chains on the petrol 159s (although there has been some issues noted on the forums regarding stretched chains).
That means in theory that my 159 will be cheaper in the long-run on maintenance costs than even our twin spark 156 (cheaper than the v6 but still over $1300 every 3 years).

On a side-note, the 159 diesel does use a belt. The 159 service book recommends the diesel belt to be changed every 150,000km's or "...every 3 years if the vehicle is used in one of the following particularly harsh conditions: prolonged used in hot/cold climates; town driving with a lot of idling; use on particularly dusty roads."  Ozzie driving probably ticks the prolonged hot climate box, and driving in Sydney or Melbourne would tick the "lot of idling" box.

[colcol]

With that sort of distance of 150,000, you would say its a non interference type motor, so if the belt breaks, tow it to the mechanics and fit a new one, as you know the diesel engine in the 159 is made in Italy by a specialist diesel engine maker, that among others makes the diesel engines for Rover, the diesel in the 159 is an absolute ripper all that torque, and most importantly its an Italian car with an Italian motor, good stuff!, Colin.

[bteoh]

Just paid almost $2800 for a service and cam belt and water pump change for my 156 GTA. There were a lot of problems with the dealer and service that I won't care to mention but will try to get them sorted out tomorrow when I take it back. Last cam belt change was 50000kms by PO 4 years ago and it's done 74000kms now
However, I noticed the idle doesn't appear to be as smooth as I remember it to be. Almost feels like a very slight miss fire occasionally when idle but when the car is going and revving higher, it seems fine. Anyone have any ideas what could have transpired or is that normal? Would a tooth out on one of the cams cause that?
On another note, I had my 1999 Subaru 2 door STi in for a cam belt change - I have had it since new and this is the first cam belt change (12 years) , as the car has only done 49000kms. I was told and shown the old cam belt was almost like new and the rubber and teeth were still very supple with no hint of dryness. I know I was stretching it a bit as the Subaru boxer motors are interference type and redline is 8000rpm...... but it's good to know there's a good safety margin with the Subaru. (The Subaru cam belt change cost a fraction of what the Alfa belt change was   ) .  I don't think I will take the chance with the Alfa and will have to follow the recommended service / cam belt interval  ........