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Sounds bodgy but...
chriscook - 26/11/07 at 09:17 PM

Has been suggested that I change cams on my XE leaving the existing hydraulic followers in place.

Thoughts?

(Picked up some cheap Kent cams for my rebuild - only very mild though.)


blakep82 - 26/11/07 at 10:17 PM

have a look at the qed web site, and sbd. one of them had some info on when you should start to look at solid lifters.

don't blame me if it all goes wrong! but mild tune should be ok from what i remember


chriscook - 26/11/07 at 10:57 PM

Sorry. That's not what I'm asking. I know they are a hydraulic profile.

The question I am asking is whether it is ok to use used hydraulic followers with a new camshaft?


blakep82 - 27/11/07 at 12:27 AM

oh, i see, i thought you meant swapping to solid lifters...

don't know.


Werner Van Loock - 27/11/07 at 08:01 AM

Well, from the burton power catalog it states that you should always change lifters with cams. And I also heard that on a 1.8zetec, when you go 2.0 zetec cams that you should change the lifters with it.


Ivan - 27/11/07 at 11:15 AM

The rule is always change lifters with cam as old lifters can significantly reduce cam life, so the choice is whether you want to gamble on having to buy new cams and lifters down the road a bit.

So it's all down to simple economics.


ned - 27/11/07 at 11:21 AM

I'm running old lifters on my 220bhp xe. It's not run much but made good power on the rolling road. As long as they fill with oil and quieten down ok after you start the engine they should be fine imho.

Ned.


awinter - 27/11/07 at 12:55 PM

How many miles are you going to do a year?10000, change the lifters, 1000 leave em. Chances are you will never do the milage to wear the cams even if things are not quite right. depends also on how much a set of replacments are, sometimes it pays to ask a few engine builders as they can often source these things for way less than main dealer or other sources. Try Autosprint.
As long as the existing lifters are not worn and you run the new cams in according to instructions it should be fine. just make sure if you take the lifters out of the head to put them back in the hole they came out of. If you mix em up it can cause wear on the lifters.

ta

Allan


NS Dev - 27/11/07 at 01:06 PM

Right, do the job right, DON'T use the old lifters AS THEY ARE........

Re-using them is fine, but they need a lap over before they run on the new/"different" cams.

You can do this with very fine wet and dry paper and wd40, on a sheet of glass. Stick the paper down abrasive side up on the glass by spraying it generously with the wd40, then abrade the working face of the followers on it in a circular motion until the faces are an even grey all over.

Once this is done, they will bed into the new cams fine. I found this out a few years ago from Dave Andrews, and have since done this successfully on two engines with good results.

Here's a quote from Dave Andrews website, hope he doesn't mind (doubt he will)

"Re-using followers

Although strictly speaking followers should be replaced when fitting new cams, this is largely unnecessary provided the followers are in good condition. Whether or not you are converting the followers to solid operation they should be planished before fitting with new cams so that the surface is perfectly flat and the new cam beds in correctly. The followers can be planished by placing some P240 wet/dry paper upturned on a truly flat surface (a metal bench or small sheet of glass). The flat surface of follower is then rubbed over the surface of the abrasive paper with a slow circular motion, lubricate the abrasive paper with WD40. Discard any followers which have heavy pitting or heavy rusting, these will not be suitable for re-use. Light scuffing and other light radial marks can be removed by planishing. Inspect the surface of the follower regularly, and turn the follower constantly. The planishing is complete when the face of the follower has a burnished appearance and none of the original wear marks or scuffing is visible from any angle.

Below are pictures of a follower before and after planishing, note the radial marks and light scuffing on the follower surface before planishing, this is normal."





MikeRJ - 27/11/07 at 01:42 PM

I believe the correct term is 'linishing' as 'planishing' generaly invoves the use of a hammer