K series Hydraulic Cam Followers.....again

[Ivaan]

A week or so ago, my 1.6K Roadsport developed the tick. Possibly a surge problem. At first it disappeared after a few seconds, but today, it developed into a permenant noise....( had to be on the best w/e of summer )....but I can't drive her like this. Why does this happen? Surely the follower would pump up as normal, with the air in the system displaced. This is now happening as soon as oil warm, even pootling through town. I'm using fully synth oil 10/40, (recently changed). The car's only done 15,000 miles..no trackdays... Avon ZV1's, though I do chuck her around quiet a bit ( but that's the point of a 7 )..No appollo.

So I'm going to strip out the cams and followers to open up the oilways ( as previous posts on here ). I'm assuming this can be done with the head on. This is where I'm hazy on the process of sorting the oilways. I need some advice on this.....please!

 

I'll be replacing the standard cams with Piper 633's and verniers on rebuild and upgrading the ECU.

 

 

[The Polisher]

 

You can match up the oilways with the head on but need the cams off as you suggest.

 

The problem with the Rover cylinder head is in the inconsistancy of angle of the oilway drilling that feeds the followers. This should line up with the oil groove of the followers when the valves are closed (as they all will be with the cams removed). In many cases the hole breaks through into the follower bore too high up therefore starving that follower of oil.

 

With the followers still in place, look down each oilway with the aid of a torch and you should be able to see at least two thirds of the groove. Those which do not align require the follower end of the oil hole opening up in the relevant direction using a dremmel with ball end burr.

 

Remove the follower with a magnet and cut an oval disc of plastic to fit into the follower hole to collect the swarf produced.

 

Check each Follower and replace any that are spongy as a precaution in case they are faulty.

 

Dave H.

Mad about S77ENS

[Ivaan]

Thanks Dave...I'll hopefully be able to strip cams off in the morning and will inspect followers/oilways as you suggest. Once sorted, I'll plannish the followers as suggested on Oily's website, before installing the new cams.

 

Any other pitfalls to watch out for doing this?

[The Polisher]

 

The head casting had to be fettled away to clear the cam lobes of my BP 285H cams. Check with Oily if this is needed for the 633 cams.

 

Dave H.

Mad about S77ENS

[Grubbster]

My DVA upgrade that fitted 633 cams didn't require any grinding to clear the lobes so you should be fine.

[oilyhands]

 

Normally the 633s go in with no fettling on the tops of the follower bores, however casting/machining shift , casting anomalies in the cams and head can sometimes cause the odd problem, best thing is to remove the followers and do a trial rotation.

 

 

Oily

[Ivaan]

Thanks for the help and support.

 

I've removed and replaced the followers one at a time. On one of the inlet followers, there was a tiny piece of gold coloured metal blocking the oilway hole, which might have been the cause of the problem. I've flushed this out and fettled the oilways. The followers themselves appear in good condition.

 

Any recommended way of cleaning off the old sealant from the faces of the cam castings?

 

I'm now going to drop the sump, to see if there's anymore debris about......hopefully not! I'll remove the foam and drill the gasket as per Oily's suggestion...

 

Oily...When are you back? ( only answer if Mrs Oily allows ). Hope you're having a good time.

 

Cheers all...

 

Clive

 

 

[Englishmaninwales]

Any recommended way of cleaning off the old sealant from the faces of the cam castings

Carb cleaner works well.

 

I had this problem, as Dave H describes. All of the exhaust drillings were out of line.

Malcolm

[Ivaan]

I've managed to clean the surfaces up pretty well with petrol, but will get some carb cleaner to finish it properly.

 

Thanks for the heads up on the casting. Not a problem that I'd have anticipated. I assume that I'll have to put the cams on and time them roughly, before hand cranking the engine over to find any fouling. Then if anything does foul, strip it all again to fettle. Or is it possible to see before assembly?

 

Cheers all.

 

Clive

[Ivaan]

By the way...sump was clean... *thumbup* 😬 *thumbup*

[The Polisher]

 

As Oily suggests, remove all the followers, rest the camshaft in the half journals and rotate slowly checking for fouling on the casting.

 

Dave H.

Mad about S77ENS

[Ivaan]

Dooh!

 

Note to self :- read and digest all posts before sticking foot in mouth or fingers on keyboard.

[Ivaan]

Me again......

 

With my cam supplier away on a looooooooong holiday, and the 50th fast approaching, I decided to put the original cams back in. All went well, timing/verneirs sorted ect.

On engine start, there was a quiet tick for about 40 secs, which disappeared before I left the driveway. All was quiet for about 6 or 7 miles, when the loud ticking started again ( I was taking it very easy ).

With the followers apparently in good condition and the oilways open, why would this come back? Is it possible for a follower to be faulty? Should I replace them? Or is there anything else which could also be giving these symtoms? A broken piston ring wouldn't disappear, would it?

The engine's been well maintained and only done 15,0000 ml.

 

PS. After a dry fortnight, with no car, it started raining just as I left the garage.