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View Full Version : Megane Cylinder Head! Overhauled F7R 710 head



jwarren2k2
25-05-2007, 23:30
Its on ebay, and this is basically what is on the auction advert! The buy it now is £220, so make me an offer! I can arrange delivery, £25.


The cylinder head has been overhauled (costs around £350 for an overhaul) to renew it's condition. I did the work myself, I am an engine reconditioner. Reason for sale is that i bought the engine to put into my Clio 16v, but a bottom end bearing had gone resulting in a bent conrod and very bad crank, and I can't afford to get another bottom end now, as I've already started on another project!



Work that has been carried out:


Head removed from engine and stripped completely, numbering the valves so they could go back in the same place when rebuilding.

Head was then acid dipped to thoroughly clean all the carbon and oil build up.

The valves, springs, spring seats, spring caps and collets were all put in a hot chemical wash.

Valves were then bead blasted to get rid of all the carbon, then re-faced. (All valves are straight)

The guides were a touch worn, so I fitted 'K-Line' guide liners. These are bronze liners (Very hard wearing) which fit inside the guides and are then sized using a ball-broach. The valves now fit as new, with a tiny amount of play, which obviously is needed so they can move!

The next step was re-cutting the valve seats. These have been cut to within a 0.003" (3 Thou) concentricity tolerance.

Once all the seats were suitable, I lapped the valves in using lapping paste (The brand escapes me at the moment).

It was then time to give the head a surface skim. I skimmed 0.008" (8 Thou / 0.2mm) off the head face to ensure it was completely flat.

I was then ready to rebuild the head. New Payen valve stem oil seals were fitted, along with the spring bases, valves, springs, caps and collets.

I then fitted the original cams using Graphogen (Graphite engine building paste) which ensures that the cams don't turn and run dry upon first start up. The cam caps are not torqued down, this is so the valves can't be damaged in transport if being delivered.

The cylinder head is now wrapped in film to keep the dust and dirt out, and so it can't be damaged.

I'll hopefully get some pictures of it up tomorrow.



I am able to supply gasket sets and performance cams (Piper and Kent) if you wish, aswell as Jenvey throttle bodiesand aftermarket ECUs. I can also Gas-Flow (Port & Polish) the head for you.



Thanks,
James

jwarren2k2
05-06-2007, 21:39
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