Technical Is it dead?

[topher]

OK, story from start to death. Changed fuel filter, sheared a bolt but overcame that with no major issues. Ran the engine for 10 mins to warm oil up, then drained oil, put in some COmma flushing oil, ran it for 8 minutes at idle and up to 2000rpm, then in a blind stupidy moment, reved the car to 3000rpm, after about a second a noise, a bad noise, described by my partner in crime as 20 bottles smashing at once, followed by a jiggling bag of spanners, turned off ignition after about 2 seconds of noise. Flicked engine over for a second, normally it would have started but now it just seemed to turn over much faster than before, with same horrible noise. So cam cover off, cam belt is still fine, cant see anything out of the ordinary with the cam shafts.I have drained the flushing oil out and ran a magnet though the drain tub but couldnt find any bits of metal. Took the spark plugs out and they are fine, cant see any marks on top of the pistons (through spark plug holes)

Can any one think of what I may have done? After 1 hour of talking, Dan (partner in crime) and myself have decided we can conclude it is not good but cant get any further than that!

Any suggestions of what to check next would be appreciated.

Chris

 

[Rustbucket]

Puzzled as to why the extra 1000rpm has broken something which it obviously has...

If the engine is turning over much faster than usual and making a horrible noise I would guess pistons and no compression? Get hold of a compression tester and check each pot to see what the compression figure is. Not sure of the exact figure for the B but I'm guessing from other Fiat engines that it should be around 160psi? You should find 3 readings similar,+/- 10% and one probably 0.

I had a coupe that threw a valve in style (at 120mph on a circuit) and the repair bill for pistons, valves etc came to £2000. Most of it being labour.

Your choices if the engine is totaled depend on how much you value the B. Mileage, condition, wallet etc.

I may be able to sell you a perfectly good engine with 45k miles on when my B goes in for a coupe 4 pot turbo conversion.

 

[topher]

Rusty, Will check compression tomorrow, I was looking for opinions as checking the compression means turning the engine over and so possibly causing more damage, I guess there is no other way of doing it really. I cant believe it is completely goosed but if it is then I would be looking for a new engine rather than breaking the car.

 

[Alan.D]

Is it possible that the belt has slipped rather than snapped, check the timing marks for both camshafts with the crank at TDC.

Happened to me once before in my 525BMW. on acceleration it was fine but slipped when I decelerated.

If it's turning quicker at the starter it sounds like there is less compression. I hope to hell it's not bent parts.

 

[topher]

A belt slipping? Not something I have heard of but I am at a loss to explain this any other way! All I did was raise the revs gently to 3000rpm then all hell kicked off! If the belt did slip and the noise is valves and pistons kissing then I cant see any other option but to take the head off, actually having a read of the service manual, doesnt sound too bad but I bet the exhuast manifold studs will be a pig!

So, wife is out on the town tonight so she will be in bed till mid day tomorrow, so I have a morning to check the pulley alignment.

Thanks for the reply, at least I am not missing anything obvious.

Regards

Chris

 

[Alan.D]

As well as timing marks have a look for missing teeth on the belt. I'll keep my fingers crossed. Just thinking the plugs are directly above the pistons so maybe worth removing them and checking for valve marks on the pistons with a small torch.

 

[topher]

Alan, I did that last night, tops of pistons, from what I can see look fine. I have got the car up in the air at the moment but the front is on ramps so I am going to get an axle stand under offside wheel and take the timing cover off, maybe the tensioner went?? Anyway, if all looks ok on the cam belt, I will do a compression test. Update later on hopefully!! I guess its reasonable to concentrate on the top end as if it was the bottom end, I would have hoped to see some metal in the drained out oil.

Thinking back now, the sound was what i would expect valve to piston to sound like, lots and lots of little smashes!

Regards

Chris

 

[Alan.D]

Good luck.........

 

[topher]

Quick update, got cam belt cover off and can see that there are several pieces of metal in the area around the belt, they look like the teeth off either the cams or the main drive wheel but I cant see any missing at the moment, anyway, the engine doesnt turn over by hand, but does turn through about 270 degrees then seizes and the timing belt goes slack. Quick break for a cup of tea then back to it, photos to follow when I can find the camera and when I can find something of note to take a picture of!

 

[topher]

As I said in the earlier post, I got the cam cover off and found that the teeth I had discovered earlier are off the automatic tensioner guide pully. It should a carbon type sproket on it but that has broken up, I have found quite a few of the pieces but have to remove pulleys etc to find the rest I thinkg and make sure it is all removed. This breaking up has allowed the cam belt to come loose and thus the timing to slip. The cam pulleys have 2 white marks which I think should like up to the two white marks on the cam shaft cover, put on by a previous owner to d the cam belt, anyway, the white marks no longer match up so the timing has slipped. The engine does turn over by hand now so either the valves are bent out of the way or the noise was the carbon pieces being flung around. My best guess is that when the belt has been changed in the past, the tensioner pulley was not changed and it has just given up. But I am no expert so welcome anyone elses comments.

Is the pulley breaking up a result of something else failing or is it just bad luck it went? The options are to change the timing belt and tensioner pulley and re time the engine and fire her up or to lift the head and inspect the valves and change the head gasket. I am leaning towards changing the belt and pulley, re-time and then check compressions, if all seems well then go for a start. At least I will be saving myself cash as I am doing the cam belt rather than paying fiat to do it. i did order the locking tools this morning so cant do much till they arrive.

Photos below!

 

[Hugh Snape]

A while back I had an inlet valve stick in it's guide when driving at speed. This jammed the camshaft which in turn broke the variator but did not damage the cam belt etc.

When the RAC man turned up he was very surpised to be confronted by an engine which would turn over yet had a stationary camshaft but an unbroken, and moving, cam belt.

Cost quite a bit to get the head machined etc I'm afraid.

Good Luck

Hugh

 

[Nino_1975]

Bottom end could have gone.... Then you will need a new engine.

Happened in a 156 my brother had. Same symptoms.

Hope it's not that bad though....

 

[topher]

Nino, Can you explain why you think the bottom end may have gone, do you mean the bottom end may have gone and this caused the tesnioner to destroy itself or are you meaning the tensioner failing may result in the bottom end being wrecked - and if so the only damage could really be damage to the pistons where they have met the valves - does it really cause so much damage to the pistons after only a few seconds running?

Thanks for the reply.

Regards

Chris

 

[Alan.D]

The way I see it Chris you have 2 options....

1 Try to save as much dosh as possible, replace the cambelt the tensioner and see what happens (but no matter what else with the exception of an engine change you would need to do this anyway)
BUT if you go down this route and the valves let go after being weakend then most certainly a valve will hole a piston (a chance you have to take for option 1)

2 Remove the head check all of the valves give a good clean, skim the head and all may be well for the life of the car?

No matter what, you need to find out what caused the tensioner to fail?

 

[topher]

No matter what, you need to find out what caused the tensioner to fail?

THat may be the $1,000,000 question! Could it just be unfortunate or is there something that can happen which causes the tensioner to shatter. Your post gives food for thought Alan, I was thinking along the lines of, if the compression is OK then the pistons and valves didnt meet so all should be well but your post suggests that may not be the case. Anyhow, see your points, will replace timing belt and tensioner and see if the engine turns over ok and if compression is ok then go for it. I did notice a small amount of gunk on the oil filler cap, just like a head gasket failure - and I did make the point in another thread that the coolant was low when I got the car so head off may be required anyway, I was just thinking that because the car had been sat for a while, the oil mayu have a bit of water in it from condensation but that is probably wishful thinking!

 

[desert rat]

I have an old cambelt here and I have a feeling I may have an old tensioner as well (will check in the shed tomorrow. If they are of any use to you to check things out you can have them. (may take a while to arrive in the uk though, if anyone there kept the old parts then you would get them sooner).

If the engine failed to turn over by hand I think there may be more damage than the obvious.

I think alans advice is worth following. but I would try to use 2nd hand parts if available to check that nothing else is screwed up. If after setting things up turn eng over by hand if ok do a compression test. (if something has broken / siezed inside then I guess hte engine is already toast?

Have a feeling a new engine from the scrappers may be the cheapest option?

I have never seen a tensioner break before... ??

 

[Nino_1975]

Nino, Can you explain why you think the bottom end may have gone, do you mean the bottom end may have gone and this caused the tesnioner to destroy itself or are you meaning the tensioner failing may result in the bottom end being wrecked - and if so the only damage could really be damage to the pistons where they have met the valves - does it really cause so much damage to the pistons after only a few seconds running?

Thanks for the reply.

Regards

Chris

Chris
Sorry I can not help, it just sounds like my Brovs car when he tried the same and the bottom end (the bottom of the engine) was the fault afterwards. I could be talking total crap.:idea:

 

[Alan.D]

the oil mayu have a bit of water in it from condensation but that is probably wishful thinking!

It is highly likely if the car wasn't getting used much I used to get lots of condensation in the 735 if I made short journeys and did see it often in the B.

I know the options are a bit vague (sorry) My only fear is that as the valves are very hard steel it makes them very brittle, it's more than likely that they are ok but wouldn't be planning a trip to France for the first few hundered miles

 

[topher]

Morning, the engine did turn over on the starter it just made a horrible noise, I put it down to the valves and pistons repeatedly hitting but now I have removed all the graphite from the cam belt area, the engine does now turn over by hand and feels OK to be honest! I can see the valve timing is out so the belt did slip (as indicated by painted marks on the cam from last belt change). I think i will try get the head off tonight and take a peak. If the head looks OK and the bottom end turns over freely then re-assemble with new gaskets and then replace belt and tensioner. I can see that a rush job is not the best way forward, we dont need the car as a daily runner so better to take a month and do it properly.

As for the tensioner failing, it is just a bearing, not connected to anything so I cant see how a failure in any part of the engine would cause that graphite sprocket to shatter. The only thing I could come up with was that the engine siezed, the belt got really tight and that caused it to shatter but I just can never see it happening!

If an engine change is needed, then so be it, I have rung a local scrappy who appears to have a 1999 Barchetta on its website but this place is known for being expensive. Will give them a shout though as it is just around the corner from me. You never know, xmas time, someone wants to get a few beers for the lads, may get it cheap enough.

Ta ta for now

 

[Mad Matt]

I've never heard of that happening before. I did have an old Nissan that managed to wrench out it's rocker bolts but I can't imagine what could have cause the tensioner to fail. I suppose it could just be a bearing locking up.....

Let''s hope the valves are OK and you don't need to skim the head!

Good luck.