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schakal
31-07-2009, 21:29
do valves and tappets need to go back into the exact
slots they came from??


if so whats the reason for this ?

col
31-07-2009, 21:45
To be honest mate , yes......its the wear factor ,each item rubs an wears differently......its a safer policy to follow 8) what you re furbin?

schakal
31-07-2009, 21:55
To be honest mate , yes......its the wear factor ,each item rubs an wears differently......its a safer policy to follow 8) what you re furbin?

just curious as ,not refurbing anything

need more specific details .
you mean the valve stems wear differently or the back of the valves
mating the valve seats ?
what about when you fit new valves , are not the valve channels allready
worn down to the old valves??

col
31-07-2009, 22:09
If your replacin with new, no probably not,but if reusing tappets runnin in different holes they could stick.

Check the aluminium sleeve of each tappet an notice the different wear marks. :wink:
,

busterhymes
01-08-2009, 07:20
To be honest mate , yes......its the wear factor ,each item rubs an wears differently......its a safer policy to follow 8) what you re furbin?

just curious as ,not refurbing anything

need more specific details .
you mean the valve stems wear differently or the back of the valves
mating the valve seats ?
what about when you fit new valves , are not the valve channels allready
worn down to the old valves??

re the fitting of new valves would always be a good idea to change valve guides at same time

Wobba
01-08-2009, 07:38
As above, new seals should be sorted. New tappets are about £60 off ebay.

If re-using tappets, should make sure you put them back in the same places as they wear a bit in different places depending on the cam etc. The tappet surface needs to spin freely as they get twisted with the cam action.

Don't forget to prime the tappets too a bit by squidging them about whilst submerged in oil. It helps.

queegan
01-08-2009, 12:26
valve guides are obscene amounts of money from renualt!

busterhymes
01-08-2009, 13:05
valve guides are obscene amounts of money from renualt!

maybe a part thats available through a good motor factors or even through an engineering company

queegan
01-08-2009, 13:30
motor factors i doubt very much maybe an engineering company i dont think u will get them through a motor factors because its such and internal part maybe wrong though. coz i tried a few places with no luck !

col
01-08-2009, 19:23
gaskets an seals from m,factors................but valves ,guides etc best to get from engine builders,motor engineering companies.

If you have new guides then youll need the valve seats to be re cut or ground.

sideways danny
02-08-2009, 03:19
motor factors i doubt very much maybe an engineering company i dont think u will get them through a motor factors because its such and internal part maybe wrong though. coz i tried a few places with no luck !as you're in Oxford, try a place called Oselli Engineering. Ask them about k-line inserts for valve guides

queegan
02-08-2009, 14:51
motor factors i doubt very much maybe an engineering company i dont think u will get them through a motor factors because its such and internal part maybe wrong though. coz i tried a few places with no luck !as you're in Oxford, try a place called Oselli Engineering. Ask them about k-line inserts for valve guides

nice 1 yeah i rang them a coupld of weeks ago about something else never thought about askin them for the guides lol i have a another place called fk payne and sons in enshym is also a good engineering place in ox

schakal
10-08-2009, 15:31
If your replacin with new, no probably not,but if reusing tappets runnin in different holes they could stick.

Check the aluminium sleeve of each tappet an notice the different wear marks. :wink:
,


where actually could they stick ?

i mean its a cylinderical object and it goes into its slot by hand
with no hassle . how can it possibly stick ? :?:

busterhymes
10-08-2009, 16:04
i suppose you wouldnt consider putting the pistons into a different bore when u reassemble an engine same sort of thinking applies to all wearing parts small irregularities in the two surfaces wear together so where u could have a high spot on one item and a low spot on the corresponding component then u can see the prob if mismatching two parts both with high spots hence the comment of 'sticking'.
all that said cant really see any major issues if u happened to put the hydraulic tappets back without noting the original positions maybe some of the guys who work with engines, craig for example could clear the matter up

schakal
10-08-2009, 16:11
i suppose you wouldnt consider putting the pistons into a different bore when u reassemble an engine same sort of thinking applies to all wearing parts small irregularities in the two surfaces wear together so where u could have a high spot on one item and a low spot on the corresponding component then u can see the prob if mismatching two parts both with high spots hence the comment of 'sticking'.
all that said cant really see any major issues if u happened to put the hydraulic tappets back without noting the original positions maybe some of the guys who work with engines, craig for example could clear the matter up

with that way of thinking , if you are fitting brand new tappets into slots where there is allready wear from the old tappets .
than how do they match ? :?:

busterhymes
10-08-2009, 17:17
thats why i added my comment that i dont see the problem of u putting then back in but not necessarily in the same place as they were removed from, i just tried to give an explanation to your question using the piston/cylinder as an example of two matched wearing surfaces

col
10-08-2009, 17:33
Dont forget,your dealin with components "cold" ,so they will fit,but when things get hot they expand, hense they may stick.

Buster had it about right actually :wink:

cliokiz
11-08-2009, 22:16
I decided to ignore all the rules when i rebuilt my head.

Boshed all the valves back in, in a random order, i only bothered to number them when i started lapping them in.

Then all the tappets i just slung them in in approximately the correct order but didn't really pay too much attention.

Most of them dropped into the 'pot' with ease and spun around quite freely, some of them got stuck when i put them in so i remove them and tried them in different 'pots' until they were all seated comfortably.

Engine has been running for 5000 miles now without any issues. Tappets sound lovely when warm, a little tappy when cold but to be expected, i didn't bother priming them.

schakal
11-08-2009, 23:07
I decided to ignore all the rules when i rebuilt my head.

Boshed all the valves back in, in a random order, i only bothered to number them when i started lapping them in.

Then all the tappets i just slung them in in approximately the correct order but didn't really pay too much attention.

Most of them dropped into the 'pot' with ease and spun around quite freely, some of them got stuck when i put them in so i remove them and tried them in different 'pots' until they were all seated comfortably.

Engine has been running for 5000 miles now without any issues. Tappets sound lovely when warm, a little tappy when cold but to be expected, i didn't bother priming them.

thats exactly what i was after :D
you said you lapped the valves in which they should seal fine
have you noticed any excessive oil burning due to valves
fitted in different slots ? (i.e :through stem seals )

cliokiz
12-08-2009, 13:05
No more than i'd expect really, it does burn oil, but show me a valver (or in my case, F7R) engine that doesn't.

No smoke out the exhaust.. although i'm running a cat so i probably wouldn't notice anyway.

The car has since made 156bhp on the rollers, and it's the first time i'd ever touched engine internals, so it can't be that bad!

webby
12-08-2009, 14:09
i have got a hybrid daily driver and also a spare 16v head with 16v cams. what sort of work could i do to the head to make it better than the 1 i have fitted? as i would love to do some work on it then swap them over. would i keep the valver cams or put f7r ones in?

cliokiz
12-08-2009, 16:39
F7R cams would be better.

Apart from fitting new valve seals, new valve springs, new tappets, etc, there's not much else you can do unless you want to do some headwork to improve performance or maybe machine it to fit 33mm valves.

Would be a good chance to fit some uprated cams though.

col
12-08-2009, 18:03
But you get my point <IF you hadnt checked your tappets an just pushed em in......your engine would have sounded like a tap dancers convention :wink:

webby
12-08-2009, 18:42
F7R cams would be better.

Apart from fitting new valve seals, new valve springs, new tappets, etc, there's not much else you can do unless you want to do some headwork to improve performance or maybe machine it to fit 33mm valves.

Would be a good chance to fit some uprated cams though.

this is my idea, i have the head ready and removed so i can work on this 1 as much as i need. has anybody got a guide to working the head at all? i.e flowing, porting etc. where could i get it machined?