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  1. #1
    Non-member mike r5 gtt's Avatar
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    f4r no compression/timing

    evening all, been a while since i played renaults and am having a real head scratch moment....i have fitted a f4r engine today and it has no compression

    it has new plugs, good fuel, spark etc.
    fitted a new dephaser and belt.

    it has been timed up again and all seems spot on, the pin locates in the crank hole and locks it both ways, the "big Ds" on the ends of the cams both line up.
    Iv done the welding wire down the bore and made sure that piston 1&4 are tdc when the crank pin locates.

    the thing is if i remove the inlet mani and crank it i get flames pop from cylinder 1&4 together which makes me think its timing as all the valves should be shut.
    and i didnt think f4r's ran a wasted spark??

    if these engines have sat for a while could it be a ring/bore problem?
    or if the hydraulic tappet/lifters have been sat could can they cause issues?

    i hav'nt physically compression tested it yet coz i didnt have my tester but it spins over like there are no plugs in it.

    any one any idea's other than a leak test?

  2. #2
    Non-member Nick k's Avatar
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    Re: f4r no compression/timing

    Have you had the head off before ?? And was it running before etc, this is what you get with a classic timing belt failure where it bends all the valves

    More info is needed.

  3. #3
    Non-member SCHWARTZ's Avatar
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    Re: f4r no compression/timing

    Are the lifters ok? Iirc they can get air trapped and not shut the valve properly. I would get your tester on it first.

  4. #4
    Non-member Matt@CodeRedMotorsports's Avatar
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    Re: f4r no compression/timing

    Ouch, does sound like bent valves, if you haven't got the compression tester to hand, take the upper and lower inlet manifolds off, and look down the ports, you can see if the valves are bent.
    Clio 2 172 runs a coil pack so yes it's wasted spark.

  5. #5
    Non-member Matt@CodeRedMotorsports's Avatar
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    Re: f4r no compression/timing

    Coil info.
    Attached Images Attached Images  

  6. #6
    Non-member Matt@CodeRedMotorsports's Avatar
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    Re: f4r no compression/timing

    Common timing fault.....
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  7. #7
    Non-member mike r5 gtt's Avatar
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    Re: f4r no compression/timing

    I was sure it must be a timing issue as the valves should be shut when at tdc, but I didn't realise they were wasted spark which was confusing me but the Timing is spot on so it can only be bent valves
    Also if it was a prob with the lifters the spring pressure alone would be enough to shut the valves

    This is a new engine, so I can't strip it to check iv got to take it out and send it back :/ iv looked down the bores and the valves look ok but I can't really see properly . Gona leak test it and borescope it 2moz to see if I can see any valve shaped marks on the piston

    Been busy trying to forget about it today and enjoy the sunshine and motorsport so il start again 2moz :/

    Thanks for the replys

  8. #8
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    Re: f4r no compression/timing

    Floating pulleys are a bitch.

    Have you used the proper tool set to lock it up to set the timing? The crank pin, the cam 'D' bolted to the head as well as locked into both pulleys and then the pulley lock to tighten the pulley nuts without moving anything.

    Did you use a new crank pulley bolt? They're a one use stretch bolt.

  9. #9
    Non-member TNT ANDY's Avatar
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    Re: f4r no compression/timing

    Quote Originally Posted by mike r5 gtt View Post
    I was sure it must be a timing issue as the valves should be shut when at tdc, but I didn't realise they were wasted spark which was confusing me but the Timing is spot on so it can only be bent valves
    Also if it was a prob with the lifters the spring pressure alone would be enough to shut the valves

    This is a new engine, so I can't strip it to check iv got to take it out and send it back :/ iv looked down the bores and the valves look ok but I can't really see properly . Gona leak test it and borescope it 2moz to see if I can see any valve shaped marks on the piston

    Been busy trying to forget about it today and enjoy the sunshine and motorsport so il start again 2moz :/

    Thanks for the replys

    Didn't Handy Andy have a problem with followers sticking in his new engine?

  10. #10
    Non-member mike r5 gtt's Avatar
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    Re: f4r no compression/timing

    yea i used all three renault tools, even borescoped the crank pin hole to double check i was in the hole not one of the web drillings as i know they only "butt up" on the smaller engines



    Quote Originally Posted by TNT ANDY View Post
    Didn't Handy Andy have a problem with followers sticking in his new engine?
    i have heard of this before and it was a concern but i think that even if they were all sticking then the valve spring pressure would be enough to close the valves.

    i thought if this was a prob it would have run but missed/made a noise

    the most annoying thing is that i cant just strip it iv got to wait

  11. #11
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    Re: f4r no compression/timing

    Take the inlet manifold off and stick a finger in.

    I had an engine where the penny had actually come away from the valve stem, it would back fire outa the throttle body!

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