Punto Cambelt failure
Discussion
fbloke said:
The tensioner on our Punto (98 model) has disintergrated effectively disconnecting the cambelt. The engine has been turned over when we tried to restart it after the failure.
Does any know for sure if the pistons will have hit the valves.
Thanks
Ken
Would not have thought you could tell for sure without a top engine stripdown, but quite likely in my experience....
Just being a bit lazy realy. I wont be touching it for a day or two now because I have to source the spare parts. By fluke I do have a punto engine I bought from the breakers a few years ago. Years ago I had a Cortina that had a cam belt go and I got away with it. Just hoping I get lucky again.
Ken
fbloke, I have a 98 60S and have recently done the head gasket, cambelt, tensioner, water pump etc. Having not done anything like this before, I signed up on a Punto forum and asked a few questions before I got stuck in. I'm not sure what model Punto you have, but regarding the 1.2 8v "Fire" engine, I was told that it is a "safe" engine in that the valves/pistons will not meet in the event of belt failure. Don't take this as 100% fact but that is what I was told so maybe things may not be as bad as you first thought
thepickle said:
fbloke, I have a 98 60S and have recently done the head gasket, cambelt, tensioner, water pump etc. Having not done anything like this before, I signed up on a Punto forum and asked a few questions before I got stuck in. I'm not sure what model Punto you have, but regarding the 1.2 8v "Fire" engine, I was told that it is a "safe" engine in that the valves/pistons will not meet in the event of belt failure. Don't take this as 100% fact but that is what I was told so maybe things may not be as bad as you first thought
Cheers "thepickle" seams like its worth a try without taking the head off. It is the "Fire" engine. I shall replace the tensioner and retime the cam and see what happens. Worst cse it doesnt work and I shall have to do it all again. I'll post the results.
Ken
If you know exactly what you’re doing then just ignore me, but these pics may be useful to you. They’re from fiatforum, hopefully they won't mind me sharing them. They helped me do the timing as the pic/description in the Haynes manual is not the best. On the crankshaft sprocket, the timing mark lines up where the metal on the engine goes from the straight section to an angle if you see what I mean. It will be obvious when you see it. I think that’s the bit that's not clear in the Haynes iirc. Like I said, if you're aware of all this then just ignore me
Paul
cam
crank
Paul
cam
crank
Edited by thepickle on Friday 29th December 09:52
Thepickle
Thats great those pictures help.I have done this sort of thing before but I have also made enough mistakes over the years to know that every bit of information is usefull. We have the Haynes manual and I need to double check. It apears we have to remove the alternator pully which is also has the ignition timing teeth on it. At first look there apears to be an oportunity to get this back on in any one of three radial positions, that is get it wrong!!. I shall match mark the wheel to make sure we dont do this.
I appreciate your input.
Ken
Thats great those pictures help.I have done this sort of thing before but I have also made enough mistakes over the years to know that every bit of information is usefull. We have the Haynes manual and I need to double check. It apears we have to remove the alternator pully which is also has the ignition timing teeth on it. At first look there apears to be an oportunity to get this back on in any one of three radial positions, that is get it wrong!!. I shall match mark the wheel to make sure we dont do this.
I appreciate your input.
Ken
fbloke said:
It apears we have to remove the alternator pully which is also has the ignition timing teeth on it. At first look there apears to be an oportunity to get this back on in any one of three radial positions, that is get it wrong!!
When you take the alternator pulley off, there is a tiny little hole in it between two of the three bolt holes. There is a tiny nobble thing on the crankshaft sprocket that fits into it. It is very easy to completely miss this altogether...like I did in fact! This is there to prevent the exact scenario you mention...putting it back on in the wrong position Spotted the nobley thing. What nobody knew was that there are two types of belt for this car. Belts with 3/8" pitch teeth and belts with 5/16" pitch. Sodds law came into force and with a 50/50 chance we got the wrong one.Local parts shop were excellent and we had another delivered in two hours. Dark by then so try again tomorrow.
I have taken pics and will post when job is done!!
Appreciate the input thepickle.
Ken
I have taken pics and will post when job is done!!
Appreciate the input thepickle.
Ken
Haha, yes, when I went to get my new belt I knew there were two options with different pitch but I didn't have a clue which one I needed. Luckily I'm lazy and there is a Fiat main dealer only a couple of minutes away from me so that's where I got a few parts from. I just gave them the reg plate (as we got the car new from them) and they knew which belt, of the two, I needed.
Paul
Paul
The first picture below is the new bearing leaning on whats left of the original.
There is a cover in the right wheel arch that need to be removed shown below
So we removed that and saw this (we had already removed the cam belt cover
Then we could see all the bits that fell out of the bearing (balls and some of the seal the rest was all gone !!!)
We had already discovered that there are ttow types of belt for this car.The belts at the top is the wrong type for our pullies. We have flat teeth at 3/8" pitch. The other type has rounded teeth at 5/16" pitch. The correct belt is shown at the bottom. The flat tooth belt has 108 teeth the rounded tooth belt has 129 teeth, they are both nominally the same length though.
The picture below shows the pully on our car which has flat teeth
more in next post.....
There is a cover in the right wheel arch that need to be removed shown below
So we removed that and saw this (we had already removed the cam belt cover
Then we could see all the bits that fell out of the bearing (balls and some of the seal the rest was all gone !!!)
We had already discovered that there are ttow types of belt for this car.The belts at the top is the wrong type for our pullies. We have flat teeth at 3/8" pitch. The other type has rounded teeth at 5/16" pitch. The correct belt is shown at the bottom. The flat tooth belt has 108 teeth the rounded tooth belt has 129 teeth, they are both nominally the same length though.
The picture below shows the pully on our car which has flat teeth
more in next post.....
This is the Unipart number for the flat tooth belt
We marked the lower pully with a tyre pen to make the lines easier to see. The nobbley bit has also been marked to make it show up a bit beeter. (Oval poit at 6 oclock)
It was difficult to see the cam pully so we used the camera and a bit of marker paint to help
We put all the bits back on and hey presto it started first time. Raging result.
Joe (its his car) checked the tyre pressures while we were at it and charged the battery a bit. Test drive was OK .JOB DONE !!!!.
Thanks to Paul for his input. We were on the verge of pulling the head off. In the event we didnt need to.This engine at least is "safe". That is the pistons did not hit the valves without the cam running.
Ken
PS
This was Joes first job on an engine and now busily looking up tunning bits. I think he has just got "the bug"
We marked the lower pully with a tyre pen to make the lines easier to see. The nobbley bit has also been marked to make it show up a bit beeter. (Oval poit at 6 oclock)
It was difficult to see the cam pully so we used the camera and a bit of marker paint to help
We put all the bits back on and hey presto it started first time. Raging result.
Joe (its his car) checked the tyre pressures while we were at it and charged the battery a bit. Test drive was OK .JOB DONE !!!!.
Thanks to Paul for his input. We were on the verge of pulling the head off. In the event we didnt need to.This engine at least is "safe". That is the pistons did not hit the valves without the cam running.
Ken
PS
This was Joes first job on an engine and now busily looking up tunning bits. I think he has just got "the bug"
thepickle said:
That tensioner looks thoroughly buggered!! I'm glad you got it sorted ...especially without having to take the head off (I know all about the hassle of that!) That feeling of satisfaction when it all comes together and works is well worth it isn’t it
Paul
Paul
You'r dead right! Joe and I were well chuffed when it worked.
Ken
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