Hi Guys, I need some expert advice please.
The History: A friend of mine gave his very good series 2 to someone to store for 2 months. When he went to collect the car, "someone" was nowhere to be found nor the car. A few days alter i traced the car to a local "backyard mechanic" The tappett cover was off and so was one of the carbs. A few days later the maechanic called to say the car was running and I could collect it.
The car had suddenly developed quite a loud knock. We have checked the cam timing (one of the models with the timimg mark on the front of the cam gears), we have had the head off and all of the pistons have marks from the valves, but piston 1 is the worst. The mechanic claims that the head was not removed, nor were the cams. All he did was set the tappetts
We have checked the valves and the seats, and the head for flatness and all seems fine. (the mechanic told us the car was given to him by "someone" as it was overheating
The owner of the car has rebuilt 14 Fulvia's and he is stumped.
Anyone got any suggestions
Valves Hitting Pistons
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william
Re: Valves Hitting Pistons
With setting the tappet play this could never happen. Only if the cam timing has shifted. You said you checked the timing before you took the head off. Was it ok?
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phil Laing
Re: Valves Hitting Pistons
Hi Huib,
I Check it by checking the timing mark on the fly wheel and the marks on the camshaft. This model has cams with the marks on the front of the cam gears.
As a seperate subject, we (The cape lancia club have set up our own website and their is a link to yours posted) You may want to have a look at www.lancia.za.org
Phil
I Check it by checking the timing mark on the fly wheel and the marks on the camshaft. This model has cams with the marks on the front of the cam gears.
As a seperate subject, we (The cape lancia club have set up our own website and their is a link to yours posted) You may want to have a look at www.lancia.za.org
Phil
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Neil Cundy
Re: Valves Hitting Pistons
I would check it by taking the plugs out and placing a long screwdriver through the plug hole whilst turning the engine by hand (jack it in gear and turn one of the wheels - other one has to be held so you loose the diff effect). Then you can check screwdriver position against the cam and valve position easily and with 100% thruth, without relying on markings that may not be correct.
But I have to ask why are you doing all this ? If there are valve marks on the piston heads someone has mucked about with the timing or it has slipped, fact. If they are no longer hitting the piston them someone has re-set the timing or it has unslipped (hmmm......).
Unless the chain has jumped enough teeth to allow the valves to hit the crowns the slipping theory is a bit weak. A check of the chain slack and tensioner condition should confirm if this is a plausable failure mode.
I know it sounds ridiculous but the flywheel, crank pully, and cam pullys are all firmly located on their respective cranks and cams are they ?
Then probably back to the mechanic for a more concise description of exactly what he did !
But I have to ask why are you doing all this ? If there are valve marks on the piston heads someone has mucked about with the timing or it has slipped, fact. If they are no longer hitting the piston them someone has re-set the timing or it has unslipped (hmmm......).
Unless the chain has jumped enough teeth to allow the valves to hit the crowns the slipping theory is a bit weak. A check of the chain slack and tensioner condition should confirm if this is a plausable failure mode.
I know it sounds ridiculous but the flywheel, crank pully, and cam pullys are all firmly located on their respective cranks and cams are they ?
Then probably back to the mechanic for a more concise description of exactly what he did !
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Neil Cundy
Re: Valves Hitting Pistons
Another possibility (i.e. very long shot 
whilst being driven by persons unknown it hasn't had a timing chain failure and been quietly replaced has it ?
whilst being driven by persons unknown it hasn't had a timing chain failure and been quietly replaced has it ?-
Neil Cundy
Re: Valves Hitting Pistons
Another couple of thoughts (it's been a slooowww day at work !)
Is the knocking coming from the top or bottom of the engine, and what condition is the oil in ?
I ask because "adjusting the tappets" as a solution for "overheating" is a new one on me. I wonder if it had a water pump failure (hence overheating) and in replacing the pump the "mechanic's" first attempt at resetting the timing resulted in the valves and pistons meeting. And is the knocking not a result of this but a result of water in the oil from the original failure, maybe a big end bearing on the way out ??
Anyway I'm getting in to conspiracy territory now so no more from me
Is the knocking coming from the top or bottom of the engine, and what condition is the oil in ?
I ask because "adjusting the tappets" as a solution for "overheating" is a new one on me. I wonder if it had a water pump failure (hence overheating) and in replacing the pump the "mechanic's" first attempt at resetting the timing resulted in the valves and pistons meeting. And is the knocking not a result of this but a result of water in the oil from the original failure, maybe a big end bearing on the way out ??
Anyway I'm getting in to conspiracy territory now so no more from me
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Huib Geurink
Re: Valves Hitting Pistons
Are the marks from inlet valves, outlet valves or both?
Checking the marks on the cogs is not good enough. The marks are there to indicate the position the camshaft should be in when assembling the engine. Setting the exact timing is done by checking the valve clearance at TDC. It should be 2,2 mm following the procedure as described in the Data Tecnici.
It can be off 20 degrees using the marks only.
But as Neil suggests use a screwdriver (or the back end of a digital calliper) to make sure the piston is at TDC when the mark on the flywheel aligns. On the 1300 engines the flywheel can only be mounted in one way. It can't be wrong. But the wrong mark may have been used.
Checking the marks on the cogs is not good enough. The marks are there to indicate the position the camshaft should be in when assembling the engine. Setting the exact timing is done by checking the valve clearance at TDC. It should be 2,2 mm following the procedure as described in the Data Tecnici.
It can be off 20 degrees using the marks only.
But as Neil suggests use a screwdriver (or the back end of a digital calliper) to make sure the piston is at TDC when the mark on the flywheel aligns. On the 1300 engines the flywheel can only be mounted in one way. It can't be wrong. But the wrong mark may have been used.
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phil Laing
Re: Valves Hitting Pistons
Hi Huib,
When you speak of Valve clearnace, you are not talking about Tappett clearance? Valve clearance being the distance between the valve fully open and the top of the piston.
I think I have the "Data Tecnici" manual on the CD's I purchased from you. Do you know what page (pdf) it is on?
Regards
Phil.
PS did you check out our website?
When you speak of Valve clearnace, you are not talking about Tappett clearance? Valve clearance being the distance between the valve fully open and the top of the piston.
I think I have the "Data Tecnici" manual on the CD's I purchased from you. Do you know what page (pdf) it is on?
Regards
Phil.
PS did you check out our website?