cam timing

[jesfirth]

Help needed please. The timing on one of the banks of my 4.2 is out. How do I adjust it?

thanks in advance

[trackcar]

the cam pulley is slotted .. slacken the four allen bolts holding the cam to the pulley, rotate cam to correct point, tighten bolts up again ...

[Toady1]

so they have vernier pullies on them do they? thats cool to know!

[trackcar]

not a vernier pulley in the true sense .. more like a slotted pulley to take into account *production tolerances* i would imagine. a bit like the soltted ball joint mounts on the suspension .. the slots never end up in the same place so is it slotted to allow you to play with the suspension or slotted to allow you to dial out chassis differences ... lol

[simonsparrow]

jesfirth said:

Help needed please. The timing on one of the banks of my 4.2 is out. How do I adjust it? thanks in advance

How do you know this?

[jesfirth]

Thanks trackcar. Will play with it tomorrow

[GreenV8S]

Your question implies that you've never done this sort of job before and haven't got as far as opening it up yet. Just four bolts sounds easy, but I would regard setting the cam timing as one of the harder things to get right and not something to be tackled lightly. There is far more to it than just loosening those four bolts and moving the pulley round a bit ... lol

[Tyre Smoke]

GreenV8S said:

Your question implies that you've never done this sort of job before and haven't got as far as opening it up yet. Just four bolts sounds easy, but I would regard setting the cam timing as one of the harder things to get right and not something to be tackled lightly. There is far more to it than just loosening those four bolts and moving the pulley round a bit ... lol

My faith in the Cerb community makes me believe that he knows this...............however get ready for a thread on Monday entitled "Turned her over and metal against metal then bang"

[Steve_T]

GreenV8S said:

Your question implies that you've never done this sort of job before and haven't got as far as opening it up yet. Just four bolts sounds easy, but I would regard setting the cam timing as one of the harder things to get right and not something to be tackled lightly. There is far more to it than just loosening those four bolts and moving the pulley round a bit ... lol

Indeed. As a starter for ten, I've heard there were no marks on the cam for timing purposes. Good old TVR eh?

[Podie]

Steve_T said:

GreenV8S said: Your question implies that you've never done this sort of job before and haven't got as far as opening it up yet. Just four bolts sounds easy, but I would regard setting the cam timing as one of the harder things to get right and not something to be tackled lightly. There is far more to it than just loosening those four bolts and moving the pulley round a bit ... lol Indeed. As a starter for ten, I've heard there were no marks on the cam for timing purposes. Good old TVR eh?

More than one way to skin a cat...

Oh, and were those Tuesday engines... or just Monday to Thursday inclusive ones...?

[350matt]

no need for marks if you 've got a degree wheel and a clock with magnetic base, most engines are like this

Matt

[GreenV8S]

I know Jes is handy with the spanners, just pointing out that this is something that is normally done by specialist engine builder and then sealed up for life. It strikes me as exceptionally unusual for somebody to want to adjust the cam timing on a working engine (how would you even know that it needed it, unless you already had the engine in bits and in a position to measure the timing?) and unless you're familiar with the process of dialling a cam in I can see one way for it to go right and a hundred ways for it to go wrong. The fact that Jes is even asking how the timing is adjusted gives the impression that this is not a job he's familiar with.

[DollySprintV8]

So if you got a Dial Gauge and magnetic base what's the setting's then from factory.

Two of the cam's I have are marked 106.

Is this 106 degre's Before or after TDC.

Sorry brain's not in gear today it's FRIDAY.

[plasticman]

that means you have the early "clatter" cams and the peak of the inlet lobe should be 106 after tdc .Set the crank to 106 degrees after tdc then try and stick the dti on the bucket , rotate the cam back and forward marking to similar points on the opening and closing ramps and the midpoint will be tdc of the lobe . Then hold the chain tight and tighten the cam sprocket bolts without the cam moving . A nice easy job !!

[DollySprintV8]

Thanks Plasticman,
I take it NO1 is O/S Bank front what about the other bank? where would you time that up from.

What way would you time up normal camshaft's.

[diycerb]

Hi, I'm checking my tappet clearances at the moment and would like to check the cam timing (DTI poised ready!!!). Looked over my cams to see if the degrees after TDC is stamped on them but only found this.

Odd cam CR1954 E287 RD3 1G
Even cam CR1953 E2866 RD3 1K

Any ideas what it means and where I might find the timing degree info. I believe the cams have been changed at some point.
Thanks Rich.

[cerbhead]

Surely THE PROBLEM is how do you set the piston to exactly TDC?? There's no TDC mark..... If you can't get the engine spot-on TDC not much point worrying about cam timing.....

[diycerb]

TDC can be found out like many other engines without marks. One way is to use a degree wheel and a stop which touches the piston crown. Half way between the two degree points of the stop is TDC.
Hopefully someone will be along with the answer I'm looking for.

[paul.a]

DIY is it a hard job to set the tappets ?? I have a 4.2 and was wondering about this job or is it best left to the experts ??

[diycerb]

Its no 5 min or easy job but if your mechanically minded and you've done it before on other cars its no different on the cerb. Feeler gauges and micrometer needed as its shim adjusted. Does anybody know the answer to my question???
Rich.