I got the refurbished cylinder head back from the motor engineers for my 2 litre Mondeo today and it is back on and will a couple of hours more work hopefully the car will be ready to go. One thing the guy at the engineers said is worrying me though. He talked about 'squeezing' the tappets in a vice before refitting them.
I have kept them immersed in clean engine oil since being removed as Mr Haynes suggested and there is no mention of having to squeeze them prior to refitting in the manual. Has anyone else heard of anything like this? I really dont want to have done this much work only to find that a simple mistake messes everything up.
As always, all constructive input will be gratefully received!
Cheers
Stuart
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they can be gently compressed to remove the oil which helps for a better 1st time start. what happens is if the tappets are expanded they hold the valves open causing loss of compression. You may find on start up it has no compression but if you turn it over half a dozen times then walk away & have a cup of tea they normally fire up when you come back,A squirt of oil down the bores helps on initial start up.
Good luck
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I hope he used carefully padded jaws to protect the machined surfaces.
There is some sense in this. If a hydraulic tappet is fully pumped up and primed with oil on fitting, the valves could hit the pistons. Compressing them all before fitment will cause the oil to be expelled and prevent this from happening. It will rattle like nothing on earth for a few seconds though, until they refill.
659.
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Prime the tappets before you fit them - don't bother with the vice business!
Once everything is together, rotate the engine by hand a caouple of time (plugs out) to ensure that there are no tight spots or 'conflicts'. Put plugs in and disable fuel pump (relay, fuse). Spin the engine on the starter a few times to get oil up to the valve gear. Enable fuel pump and away you go.
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Prime the tappets before you fit them - don't bother with the vice business! Once everything is together rotate the engine by hand a caouple of time (plugs out) to ensure that there are no tight spots or 'conflicts'. Put plugs in and disable fuel pump (relay fuse). Spin the engine on the starter a few times to get oil up to the valve gear. Enable fuel pump and away you go.
They were kept immersed in new engine oil all the time they were removed from the car so would this be sufficient? I also liberally oiled where they drop in.
They are all back in and the cams refitted but if there is any chance of a problem I would rather remove them again!
Thanks
Stuart
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Ideally you should 'pump' them a couple of time in oil before fitting - but to be honest they will probably be fine. Spin the engine on the starter a couple of times to get oil into the valve gear before you start it.
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Thanks for all the advice, I'm pleased to report that the car runs very sweetly indeed. I'm a bit worried that the water doesnt seem to be circulating very well and think the water pump might be caput. Maybe this is what caused the HG failure for the previous owner??????
Still, thats an easy thing to conquer compared to the HG change so I'm a happy man!!
Thanks again
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True, head gaskets don't fail for no reason. Usual causes are leaks, blockages or pump failure.
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True head gaskets don't fail for no reason. Usual causes are leaks blockages or pump failure.
sorry but have to disagree
many a head gasket gone due to............the headgasket
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One thing I have noticed is that head gaskets seem to fail more frequently on engines that have an iron block and an alloy head. I reckon this is due to differential expansion as the engine heats up. This must put a lot of shear on the gaskets and literally 'wear it out' over time.
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they can be gently compressed to remove the oil which helps for a better 1st time start. what happens is if the tappets are expanded they hold the valves open causing loss of compression.
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I'm not sure of the design of the Modeo hydraulic tappets, but some others I have seen have a pressed steel collar holding the 2 halves together but not taking any other stress or load when the engine is running.
It is usual on this design of tappet, to be able to easily lever off the collar and dis-assemble the tappet and drain out the old oil, then re-assemble with a small amount of fresh oil but not enough to fill the tappet.
In this way you should be safe from 'over-jacking' of the tappets, and have some fresh oil inside them also. The engine will clatter on start up initially for a few seconds but they should soon fill up nicely with new engine oil and quieten down.
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>>>>>The engine will clatter on start up initially for a few seconds but they should soon fill up nicely with new engine oil and quieten down.
Thats exactly what happened Roly! It started first turn of the key after I replaced the fuel pump relay, sounded a bit like a crossflow then after a few seconds sounded very nice!
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