turboash

hopefully somebody will be able to help me out here, my series 1 has developed a misfire its not massively noticeable on idle more so when you are driving, my local engine tuner put it down to a fuel problem,,, possibly blocked injector, so i changed the injector with spare ones i had an it made no differance. could it be down to a worn cam ????,, all obvious checks have been done leads plugs and air leak checks...... if someone could shed some light into problem i would appriciated it very much as it is really bugin me. cheers

Rick

Yes, a cam defo would cause that problem. I've serviced a few cars now like this. New cam and it's like a different car.

SafeChav

Is the top end noisy? If its not noisy then it would probably be safe to say the cam is fine.

We're all fully aware what a CVH with a worn cam sounds like so need i say anymore

Rick

they dont have to be noisey. Ive taken out some really quiet ones and there is no lobes left on them!

SafeChav

They tap when the lobes are worn.........so if the lobes aren't worn, how else could it tap (and therefore affect performance)..........

Rick

i dunno mate. If the lifter has enough travel guess it just takes up the play.
It's weird, heard some that sound terrible, and when u take them out, they look fine. Strange things.

SafeChav

Indeed they are, what usually happens is the cam wears through the hardened layer (which obviously isn't very thick) and then causes a rough edge which grinds the lifters down.

As a rule with all the CVH's ive ever played with, if the cam taps, its definately fucked, if its quiet, its all good. Obviously the tapping comes from the lifters not taking up all the clearance, as you know.

I have to agree though CVH top ends leave a LOT to be desired

LEE-RS

i had this on mine a misfire i coudnt find the fault changed everything i could think of then took the cam out and one of the lobes was just about totaly gone so it wasnt opening the valve much causing it to misfire but the cam sounded fine no tapping before hand new cam sorted it

Rick

Exactly what ive seen mate - many times.

SafeChav

Maybe i just buy shit cars then

turboash

the problem has been found, i took the rocker cover of to check the lifters and for any obvious damge, and found when i removed the lifters 4 of them had collapesed, the cylinder piece that compresses were all loose and so was the ring around the top holding the cylinder piece in,,, strange i thought seen as tho they have only done 5k, anyone no what could of caused this??

SafeChav

Cheap shitty lifters......would be my guess.

I went to the local factors when enquiring about some and was delighted to her they were about Ł4 each, then they showed me them

Get a set from Ford if you can

turboash

well i bought them from pj motorsport 60 quid thought they were decent, is it best to get em from ford then or are there beta ones, cheers

SafeChav

I'd give them a ring then. I've never known Ford ones to demolish themselves but ive heard a few people grumble about the after market ones.

I think the Kent Anti-Pump items are mena be good and they look identical in the build to OE items

turboash

cool, will give em a bell tomo, will also find out about kent ones, silly question but could i use the kent ones with my piper cam or would it be better to get a complete cam kit as my piper cam must be 5-6 yrs old and had a hard life, cheers for the info

Rick

knew it would be cam related

SafeChav

If the cam is old then its probably wise to do the whole lot, they suffer with wear very badly due to excessive spring pressures at high valve lift.

Just a question (unless you already have done this), when removing them, were any tight to pull out? If you havent taken them out already and they dont want to come out DONT force them out.

turboash

well 1 of them was tight but only had to give it a little pull with me fingers does that matter, looks like i will prob get a cam kit then just to be on the safe side,, now i have to select a cam sure there is a post about that somewhere

SafeChav

If it was a bit tight coming out then thats because that lobe of the cam is wearing, and has burred the lifter edge.

Ideally you shouldn't of pulled it out but its done now, theres the possibility you can score the bore the lifter sits in, more than likely be fine though Next time though the best way is to raise it to clear the cam, pull the cam out and drop it into the head and remove it from the cam hole

Theres more threads on cams than you can shake a stick at

turboash

just a quick update on this.... i bought new set of lifters and the misfire was still there, so i removed the cam to find no 4 cylinder cam lobes were completely round.. will be ordering a new cam this week, still undecided which one tho

Wazzzer

Yep I killed my cam on the way back from Trax a few years ago, rounded off one of the lobes, caused a misfire that I couldn't trace for ages...

I'd do an oil change as well matey, all the swarf from my cam fucked the bottom end and the turbo as well

SafeChav

Number 4 is the favourite.....a design fault on the heads means this is usually the first cylinder to develop cam lobe wear

Oddly enough though my own car munched up the lobe on number 3