Took the cam carrier and cam shaft off my Xantia 2.1td engine on which the cam belt has jumped 2 teeth causing the exhaust valves to come into contact with the pistons. The exhaust valve cam followers/ rocker arms are damaged.
The hydraulic tappets vary between being easily pushed down with a fair bit of movement to feeling totally rock hard. Is this variation down to different amounts of oil that may be in each on or are some of them faulty. If some are faulty is it the ones that are soft, ie easily pushed down, or the ones that are hard and cannot be pushed down?
Rory
Hydraulic Tappets
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rory_perrett
- Posts: 715
- Joined: 05 Nov 2001, 19:18
- Location: Leeds, Yorkshire
- My Cars: Xantia Exclusive 110Hdi Estate 1999
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I can't speak for these on a diesel, but I have done quite a few on the 16V petrol engine and with them they do have a bit of give in them when cleaned up and oiled and "burped."
With the 16V ones, it's preferrable to refit them back to the holes they came from so you don't get into strife with varying tolerances.
When removed, hold in your hand with the open side outwards and slam down onto a piece of hardwood so as to shock the centre piece out of the larger cap. The centre piece has in it a ballbearing that acts like a check valve, so the simplest way is to wash in petrol and carefully flush the oil out by pumping the ballbearing using an object small enough to fit in the hole to the bearing. Once cleaned and flushed out, I then fill the aperture with fresh oil and again pump the ball to get all the air bubbles out; at this stage when refitted to the larger cup, it should have the give in it when tested.
Upon reassembly, the larger cups have an oil groove turned into the outer circumference. It terminates at a hole that feeds the oil to the inner cup. I try to put that hole as close as possible to the feed hole that is moulded into the head as I feel (only a theory) that this, in the 16V anyway, tends to lessen the cold start rattle that can be common to most hydraulic tappet engines. According to Citroen, run a light coat of grease over the outer edges before refitting...........yes, they say "grease" but I'd suggest you don't get too heavy handed in case it restricts these oil gallies.
Alan S
With the 16V ones, it's preferrable to refit them back to the holes they came from so you don't get into strife with varying tolerances.
When removed, hold in your hand with the open side outwards and slam down onto a piece of hardwood so as to shock the centre piece out of the larger cap. The centre piece has in it a ballbearing that acts like a check valve, so the simplest way is to wash in petrol and carefully flush the oil out by pumping the ballbearing using an object small enough to fit in the hole to the bearing. Once cleaned and flushed out, I then fill the aperture with fresh oil and again pump the ball to get all the air bubbles out; at this stage when refitted to the larger cup, it should have the give in it when tested.
Upon reassembly, the larger cups have an oil groove turned into the outer circumference. It terminates at a hole that feeds the oil to the inner cup. I try to put that hole as close as possible to the feed hole that is moulded into the head as I feel (only a theory) that this, in the 16V anyway, tends to lessen the cold start rattle that can be common to most hydraulic tappet engines. According to Citroen, run a light coat of grease over the outer edges before refitting...........yes, they say "grease" but I'd suggest you don't get too heavy handed in case it restricts these oil gallies.
Alan S
RIP Sept 19th 2008.
She said "Put the cat out" She didn't mention it was on fire!!
She said "Put the cat out" She didn't mention it was on fire!!
they should not be to loose but to reset them prior to refitting them you should squeze them in a vice till they stop springing back out,then refit them flat,not full of oil they pump back up to the right distance within a few seconds,also was the engine tapety before the belt slipt the teeth,if not the the hydaulic tappets are probably ok
regards malcolm
regards malcolm