Conference terri::cars_uk

    Sounds like a nut has come loose/off on the hydraulic tappets..
    Easily replaced...lift off rocker cover and check for loose/off
    nut...and replace...!!
    
    13mm socket if my mem serves me correctly...
    
    Paul

    I'm keeping my fingers crossed that its something simple like that, but
    I've just had another bad thought, maybe the timing belt has jumped a
    couple of teeth ??????
    
    
    							geo.

    
    It would have to be a severe slip of the timing belt to
    cause the piston crowns to make contact with the valves
    but it is possible. If it was that severe then I doubt
    that it would start at all.
    
    There are couple of other possibilities.
    
    Broken valve stem. Broken valve spring.
    
    I had a broken valve stem on a 2 litre OHC engine. They break
    at the top of the stem where the valve collets hold the valve
    into the spring.
    
    Broken rocker arm (valve lifter).
    
    Not a whole lot else I can think of without hearing the 
    rattling itself.
    
    Jeff.

    
    In addition to the last note. It does sound as if you 
    have dropped a valve.
    
    Sound like a head off job to me. I hope its the
    rocker arm for your sake.
    
    Jeff.

    Re.-1
    I will try to have a look tonight and see if it's anything obvious, but
    as you said it look's like a dropped valve may very well be the
    problem. 
    
    						Cheers
							Geo.

    Found the culprit last night........Broken exhaust valve spring.
    It looks like I have been quite lucky as the spring has broke but still
    stayed in position which may have been enough to stop it from bending
    the valve. I turned the valve 360 and it did'nt stiffen up but I won't
    know completely if it's ok until I fit a spring and fire it up.
    Hopefully the repair will be done without taking the cylinder head off.
    
    							Geo.

    Do you intend to use compressed air to prevent the valve dropping
    while you replace the spring ???  I've heard about this, but never
    tried it myself ...

  Mark

    At the moment I'm trying to think of something that I could put through
    the spark plug hole which will hold the valve in place. A friend of
    mine who's spring compressor I will be using has changed valve springs
    on his XR2 using this method.
    
    							Geo.

    Can't you just turn the engine so that the cylinder in question is at
    TDC then rest the valve on the piston ?
    
    What intrigues me more is how are you going to compress the new valve
    spring ? All the spring-compressors I've seen have been like big
    g-clamps which use the cylinder head to compress against. (yes, I know
    that you shouldn't but the compresseor against the facing surface of
    the cylinder head... :-) )
    
    AmS
     

    I have a set of valve springs for an XR, are you interested?
    call me on 7844-3232.
    
    Simon.
    
    P.S. Bet you have to take the head off! If you don't PLEASE let me
    kmow how you did it. I regularly get bent valves on my Escort and
    the quickes I have managed to replace them in is 2 hrs so any
    improvement would be welcome!

    I use the XR for racing, It has a very lumpy cam in it, this
    coupled with the fact that I have a leaden right foot means that
    if the engine is over reved by more than a few hundred RPM the valves
    start to bounce and CVH engines don't like that. I have used 4 sets
    of valves in a season - 16 races.
    
    Simon.

    
    Not if you change from 4th to 1st at about 90 mph whilst trying to
    avoid hoards of lunatics trying to share the same bit of road!!
                                                     
    Simon

    The head allready has dual springs. Its unfoutunate that the head on 
    CVH engines is the weakest part of the design. The only people to
    have any sucess with naturally aspirated engines was Richard Longman
    and he spent thousands on develping a GpA engine for the DATAPOST 
    RS1600i saloons in the early '80s.
    
    Simon
    
    BTW 'Dont suppose anyone has a longman head??

    I the valve is bent, the head has to come off. If not, compressed
    air can be used to hold the valve closed (blown in via the plug
    hole ...this is how they changed the valve stem oil seals on my
    BMW without removing the head). Then use the lever type spring
    compressor to compress the spring.

    I assume that these lever type compressors must require a lot
    of different fixing points so that it can be attached to the head.
    Does anyone happen to have one and could explain where it clamps on ???

  Mark

    I belive Porsche played with such a computerised / solenoid system for
    the 6 speed box on the 959 after some over enthusiastic journalist
    wrote off a prototype ... but they decided to was too complex !!!

    I managed to get the collet out by using what can only be described as
    a magnetic-screw-picker-upper. Today is the last day of my shift so I
    hope to replace the spring tomorrow. I'll enter a note at the start of
    my next shift (Monday night) and let you all know how I got on.
    
    In the meantime thanks for all the tips and advice.
    
    								Geo.

How do you reset the Timing Belt when you are putting back on the Head?
I've looked at this in the Haynes Manual and they say that in the CVH engine
this job must be entrusted to the professional garage because the best that the
DIY Mechanic like myself can do is not accurate enough. This puzzles me -
Have Haynes been bowing to vested interests or is the job as tricky as they
say ???


- Brian. 

    AT its longest point ie; midway between the cam pulley and the crank
    pulley you should just be able to twist the cam belt through 90degrees.
    
    The tension can be adjusted by loosening the two bolts holding the 
    tensioning wheel (just above the water pump) and holding the wheel in
    the correct position by inserting a lever between the left hand end of
    the tension wheel assy and the LHS engine mount bracket.
    
    Hope this helps
    
    Simon
    

I'd have thought that all you'd need was a dial gauge to determine TDC and the 
point of max valve opening, a timing protractor to measure the degrees of
crankshaft rotation, and the timimg spec for the camshaft. Adjustment depends on
how the timing pulley is attached to the cam on the CVH - its probably either
dowelled or has a vernier adjustment. 

Nothing too difficult in either method, it just takes time and a little 
patience. I would have thought anyone who had enough diy-sense to strip down and
rebuild an engine, should be capable of setting the cam timing. Sounds like a 
case of "we think you're too dumb" to me.

re .30

I have changed many timing belts without trouble but was surprised to read that
In the "WORKSHOP" Manual 

I thought that there would be no magic involved !!!

Thanx. 

    HOW!!!!!
    

    Re.-1
    
    If you could be a little more precise as to which part of the operation
    you are unsure about I'll be glad to give you more details.
    
    							Geo.

    Sorry Geoff,
    
    I was trying to find out how you managed to get the valve stem oil
    seals off the valve stems without removing the valve springs or if you
    did, how you managed to remove them?
    
    Cheers,
    
    Simon

    A friend has an XR3i with a starting problem. After a long run he has
    trouble starting the car due to water in the distributor cap. The cap
    itself is OK but there is also water collecting in the vacuum advance 
    hoses. Could the water find its way from the vacuum hoses to the
    distributor cap or is it more likely to be the other way round?
    
    There is also a very slight water leak from a hose going into the
    engine near to the distributor. Perhaps water could be getting into the
    cap from this leak through some sort of capillary action.
    
    Thanks for any info,
    Barry.