Alfa Romeo Forum banner

156 v6 broken cam belt!.

14K views 108 replies 23 participants last post by  krisp 
#1 ·
Hi the cam belt has snapped engine lost power and stopped. What I would like to know is how much potential damage may this have caused and which engine parts do I need to take apart to find out the damage?. Looking at the engine there are no physical signs but an guessing the internals may be a different story. Thank's John
 
#4 ·
Hi I am based in Malvern Worcestershire. Unusually I have owned the car from new and the engine has done a genuine 65.000 miles. The car is in very good original condition. I am thinking about removing the inlet manifold to see if the valves are not seating properly?. Thank's John
 
#3 ·
Either a replacement engine or a replacement pair of cylinder heads is your best bet. Putting a 3 litre in is a common upgrade although you'll pay a bit more for a 3 litre than you would a 2.5.

Where are you based, I may be able to help/advise.
 
#5 ·
If you have the time/money/commitment then drop a 3.0 in it. I don't live near you or I'd show you mine. I had a 2.5 before this one came up and the difference is just night and day. You get more power everywhere and the fuel economy actually goes up as it needs to rev less. I didn't even notice the engine being less rev hungry either.

Having owned a 3.0 156 I feel the 2.5 was a deliberate compromise from Alfa Romeo.
 
#7 ·
With that relatively low mileage it could be worth while to keep the old block. Replace the heads and valves if there is no other damage to the pistons or other bits. An engine out job would make it far easier.

If you put in a used engine you will still need to have the cam belt and associated parts changed. Might as well get a new clutch at the same time if yours is manual as the engine is removed so easy access.

Out of interest, when was the last time you have the cam belt changed on your car?
 
#10 ·
The cambelt is the original one but I have kept a careful eye on it, obviously not careful enough. Just to start with how do I check the condition of the valves?. I have seen a video where by taking off the inlet manifold you can see the valves and how they are seating but this was not on a 2.5 V6 engine. I have used a local company before to rebuild the heads on my Stag, so this could be possible if the cost was reasonable. Thank's John
 
#16 ·
You can only see inlet valves and then I doubt you will get an accurate idea of how damaged they are.

only way is to whip the heads off to check properly, anything else you are just taking up time that you could put in to stripping it down.

original belt...... you really did play cambelt roulette!
 
#14 · (Edited)
I was feeling sorry for you......not now I'm afraid....... probably, a what ?, 20 year old cambelt (dont know your car year) but guessing around there!...you were lucky to get anywhere near that far. " I have kept a careful eye on it"...lol. What exactly did you expect to see?....by the time you see visible aging its usually snapped or just about to....and you certainly can't see the wear on the pulleys, tensioners and water pump....failure of any of which can cause the belt to have snapped. If you get it repaired perhaps leave the maintenance to a good indie next time and you just stick to putting petrol in....that's the little flap thing on the side btw!
 
#18 ·
Thank's for all the comments and info but still no one has told me if you could inspect the valves by removing the inlet manifold?.
The car is X reg 2000. I bought it new from Hersild and Heggoff Alfa dealers in Naerum Denmark and I drove it home, great memories!.. The car is genuine UK spec just came into the country via Denmark. Danish dealers were being offered huge discounts by the Italian factory to sell as many cars as possible. Some of you may remember Quentin Wilson giving advice on importing cars from Denmark and the Netherlands at huge discounts. Some months before the car was ordered I had a test drive at my local Alfa dealers and decided to buy the top of the range model with the sport pack 3 option, the UK dealers price was around £26,000 OTR. The danish option is the same car but MUCH cheaper, and was purchased at a very good exchange rate. The car has been rarely used so is in good bodily order and very original. I will check to date on the belt just to confirm it's age.
No doubt the heads will have to come off but as I mentioned this could never be more difficult the removing the heads from a V8 Stag.
 
#68 ·
Thank's for all the comments and info but still no one has told me if you could inspect the valves by removing the inlet manifold?.
The car is X reg 2000. I bought it new from Hersild and Heggoff Alfa dealers in Naerum Denmark and I drove it home, great memories!.. The car is genuine UK spec just came into the country via Denmark. Danish dealers were being offered huge discounts by the Italian factory to sell as many cars as possible.
-snipped-
Actually the reasoning for the huge danish discounts were the insane danish registration tax of then 105% of the first ~60.000dkk base price incl vat + 180% of the rest. Also known as “buy one car, pay for three”..
So in order to sell any new cars in denmark the factories sold way cheaper to danish dealers than eg uk dealers.. the eu killed this in the mid to late 2000s as i remember.

The 156 from new was actually an affordable car due to this.
 
#20 ·
Inlet valves are only half the story. Even without the intake tubes you cannot inspect the valves properly.
The exhaust valves are more difficult to see even with the engine out of the car.
Bit the bullet and remove the heads. The valves can be fully inspected along with pistons.
The heads are easier to remove than a Stag or Dolomite engine, all the studs are at 90 degrees to the block. Just you need washers to clamp down the liners.
937163
 
#33 ·
It's a miracle your water pump lasted all this time too!!

The 156 and the V6 are a very, very tight fit. Me thinks the bay was designed to take 4 cylinder engines!! I took one look at the internals and decided to find a good Alfa specialist to work on my own car!!
 
#32 ·
As very rough guide, remove the cam covers... Compare the height of the followers.... If a valve is not closed then the follower will appear depressed in relation to the others.. this is only a rough guide that will indicate that heads will need to removed for inspection
 
#34 ·
Just finishes removing the cam covers and other associated parts. The valves are now visible although they can not be inspected properly until the heads are off, on first inspection they do not look too bad. From what I have seen so far most of the twelve pairs of valve caps are dead equal in height. Two pairs are not so must have bent. I will post some pictures of the heads when there off, tomorrow maybe?. John
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top