Tappet clearances smaller when engine cold?

[AL3X_]

Well as some of you know i've been trying to adjust my tappets to spec and get them quiet for a while now, 02 inlet 0.4 exhaust when cold and they were still noisey, so I adjusted them to 0.2 inlet 0.3 exhaust when the engine was hot as recommended on here by someone, i decided to check these when cold to see the difference thinking they'd have widened when cold, but the gaps were smaller and I couldn't even fit the feeler gauges in at 0.2 and 0.3, now I thought due to metal expansion the clearances would be smaller when warm but they weren't, is this right or are my tappets made from stone or something lol.

[swampy]

never ever set tappets when warm!!!

do them firsdt thing in a morning and use good quality feeler guages

[AL3X_]

whys that mate, theres conflicting opinions on here?

Like I say i've set mien when the engines cold at 0.2 0.4 but its still noisey?

[blackie_2k5]

they are designed to be set when cold, this will account for the expansion when hot and still leave a proper OE clearance

and some are just noisey, mine are, its quite common for roller rocker engines to be noisey, especially when running a none OE induction kit(or breather filter), as the OE set up the rocker breather runs back into the TB and is sucked back through, reducing the noise greatly

[AL3X_]

Thats what I'd thought but there is loads of different opinions on here and its confused me greatly, I also assumed that if set at 0.2 0.4 when cold the clearances would be smaller when the engine warms up, but it seems this is the opposite?

Also, many people on here are saying GMC motorsport recommend 0.2 inlet 0.3 exhaust when the engine is warm, I did email them but got no response, is there any truth in this as my tappets are much quieter when set to that spec? I thought they were a knowledgable company?

As for the induction kit, that may be my problem then, i'm gonna see if I can implement a bit of pipe with a hole for the oil breather then attach my induction kit to that, would this work?

[DanGT]

Not to discredit GMC but I would only do them when cold. The term "warm" can mean anything from room temperature to 90 degree oil temp. Metal expends in a farily linear way so there will be a big difference in clearance in this temperature range. It is quite difficult on the TU engine to get a proper clearance due to the angle of the valve stem. so double check your gauge isn't dragging on the head.

May be a silly question but just trying to eliminate obvious things, are you turning the cam round as you go down the head? so that the cam lobe it the opposite side to the roller.

[VTS123]

They are generally tappety engines. From my experience, the smaller the engine the loader the tappets. What engine size is yours?

Bear in mind also that when you change the clearance you also dramatically alter the period that the valve is open and closed and hence dynamic compression. Perhaps GMC recommend the smaller clearance for their particular camshafts.

[AL3X_]

I dont think its dragging on the head mate as I bent the feeler gauge so it would slot in correctly, as for turning the cam, i'm doing it where I jack the wheel off the ground and put the car in third, then turn the wheel so then number one exhaust tappet is down I'm adjusting number 3 inlet and 4 exhaust I think it is as the guide says, then turning it till the next exhaust tappet is down and adjusting the corresponding ones.

As for engine size, its a 1.6 8v vtr mate, I'm not sure about what GMC mean but i've read a few posts saying the tappet clearance is "0.2 inlet 0.4 exhaust when cold, or 0.2 inlet 0.3 exhaust if you listen to GMC" and others saying to adjust to GMCs clearance when warm?

[axsaxoman]

right
firstly what age of engine black top or silver top ?
yes I always do them hot as the head which holds the cam expands away fron the rocker arm so making them wider ,which is why i say 0.2 = 0,3

[axsaxoman]

roller type rockers have very small face on the top of the valve and can wear ,so it is possible that the gap is not what you think
or maybe your idea of a fit is tighter than mine
eg you had a hard pull to get the blade out .
if you had no lift when you checked them again you would not be able to rock the arm.
next thin are you sure you postioned the cam lobes correctly both times .
remember the lumpy part of cam must be diametrically opposed to where the cam touches the roller or the rocker arm --if not then maybe you are not in correct postion

[axsaxoman]

reread what you said
awere they still noisey when ste hot?
and was there any lift in the rocker arm or was it just you could not get the feelrs in --
if they were queit and you can still feel some movement in the arm when cold ,then its not a problem ,if theres is clearance then valve is not being held open + when it warms up you get more clearance .
It could also be if it is still noisey that the roler rockers are just worn out and excess play in the spindle of the roller is giving you the rattle -not actually a clearance problem --but worn out rocker gear .
I aiways set hot cos thats when the engine is mapped + valve ltimingis importnat ot be correct .
setting clearabces tighter gives lsighty more lift = duration of cam --loose is the opposite .
the gurus on here talk about swinging cam timings etc --valve clearance has an effect as well---not a lot but a diference and on an 8v race engine you need to know how close the vlave piston is going to be when stinking hot + million rpm + missed gear change.

you are sure its not the injectors you are hearing as some are very noisey and can sound like tappets

[saxostuart]

yea figures given are clearances when cold

[AL3X_]

right
firstly what age of engine black top or silver top ?
yes I always do them hot as the head which holds the cam expands away fron the rocker arm so making them wider ,which is why i say 0.2 = 0,3

Hi mate, thanks for replying to me, i do get a bit confused with all this technical talk but i'll try keep up...its a 52 plate VTR with a 3 plug silvertop engine(well more a dark grey rocker cover but not the black HT lead type, i think its the latest of the engines)

roller type rockers have very small face on the top of the valve and can wear ,so it is possible that the gap is not what you think
or maybe your idea of a fit is tighter than mine
eg you had a hard pull to get the blade out .
if you had no lift when you checked them again you would not be able to rock the arm.
next thin are you sure you postioned the cam lobes correctly both times .
remember the lumpy part of cam must be diametrically opposed to where the cam touches the roller or the rocker arm --if not then maybe you are not in correct postion

I'm not too sure I understand this part, basically I did as the guide on here suggested where say the exhaust rocker one(nearest battery tray on radiator side) was down I adjusted number 3 inlet rocker and number 4 exhaust rocker(number 3 inlet being second closest to the ECU on the intake manifold side, number 4 exhaust being furthest toward the ECU on the radiator side) is this correct?

reread what you said
awere they still noisey when ste hot?
and was there any lift in the rocker arm or was it just you could not get the feelrs in --
if they were queit and you can still feel some movement in the arm when cold ,then its not a problem ,if theres is clearance then valve is not being held open + when it warms up you get more clearance .
It could also be if it is still noisey that the roler rockers are just worn out and excess play in the spindle of the roller is giving you the rattle -not actually a clearance problem --but worn out rocker gear .
I aiways set hot cos thats when the engine is mapped + valve ltimingis importnat ot be correct .
setting clearabces tighter gives lsighty more lift = duration of cam --loose is the opposite .
the gurus on here talk about swinging cam timings etc --valve clearance has an effect as well---not a lot but a diference and on an 8v race engine you need to know how close the vlave piston is going to be when stinking hot + million rpm + missed gear change.

you are sure its not the injectors you are hearing as some are very noisey and can sound like tappets

I adjusted them when the engine was hot to your values, so the feeler gauge came out with a bit of resistance but not a serious amount, this made the engine run a lot quieter, when the engine is cold and I check the clearances the rocker arms do still move yeah, not much compared to when warm but they do have movement up and down, the reason I got confused is just that people saying this will damage the engine at these values, yet if I set them to 0.2 0.4 when warm or cold the engine is still tappety.

[RustySkull]

Who ever said do them when hot is a tool.

Never set Tappets when hot :S

[AL3X_]

Read GMCs post mate? :/

[Morgan_VTR]

Need more clarification. Mine need doing and this contestation don't help!

[RustySkull]

Need more clarification. Mine need doing and this contestation don't help!

Don't do them hot lol.

Can't believe some people try and did them when they're hot :S

[AL3X_]

I'm not being funny mate but you haven't given any reason not to, and you've stated in your post that you adjust yours "well below spec" which I would assume worse.

GMC tunes engines for a living i'm sure if it wasn't a good idea he would know.

[Firesalx]

Looks like today must be my lucky day!:hug: Because i spent my afternoon hours today on top of my 1.4i furio to tune the valve clearances because i could hear them louder on the left side than the rest and knew that it has been the 100k mark without a clearance tune, So i figured they needed tuning.
I removed the rocker cover and took a look, turned the crank to "TDC" and then at 90deg interval turns and tried to understand the way the firing sequence was.
I think i have understood but i would like someone with a bit more of a clue about it or maybe an easier way to help me with what i have found.

Valve 1ex fully compressed Adjust 3in and 4ex
Valve 3ex fully compressed Adjust 4in and 2ex
Valve 4ex fully compressed Adjust 2in and 1ex
Valve 2ex fully compressed Adjust 1in and 3ex

Is this correct?
How do i know that i have turned the cam enough for the next pair of valves?

My name happens to be Alex too by the way:p

[AL3X_]

I think thats the correct sequence mate, if you have a search on here there is a guide which tells you the sequence, the one you described rings a bell though mate.

Basically you turn it so 1 exhaust valve is as far down to the bottom as it goes, you will need a good eye for detail at this, but you should be able to tell when its reached the bottom and if you turn the wheel a little more it won't move any further, but turn it too far and it will start to rise back up.
When its down at the bottom the ones you need to adjust will rock up and down.

Hope this helps mate :)

[logic_guy]

I have a slight idea what you guys are on about but i had a thoght

1) Haynes Manual - Well worth the £11.99. It tells you EVERYTHING

2) I would had thought set them when cold. If your car went in for a tappet adjustment in to Citroen i'm sure they would leave your car over night so everything is cold and tight. Then work on it. I'm thinking that calibrating something like this would need to be cold. When everything is tight and in its 'Natural position'

My theory is. Obv metal expands more and more as it gets hot. How do you know the optimum temperature as to when to adjust them? You stop the engine and when you remove the rocker cover, allot of heat will escape. Basically i don't believe you can set them when hot as #1 At What temperature when the engine is hot would you adjust them and #2 As soon as you stop the engine, it would drop a few *C immediately, this making the metal retract. Over the space of a few minutes (The time it may take to adjust the tappets) the engine temp could had dropped a hell of allot *C meaning your constantly adjusting the tappets while the metal retracts, thus meaning the engine will get colder and colder.

I'm no A* Science geek or a clever kid, but i believe i have thought what i have said.

Just my two cents.

[AL3X_]

It does make sense what you say mate, but like I say GMC is an experience engine tuner and after following his method my tappets are a lot quieter so i've chosen to leave them at that. The tappet clearances widen when the engine warms up which is what the engine runs at most, and so is therefore safe to do. I have also checked that there is deffo still a clearance when the engine cools down so they are not too tight.

If my tappets were nice and quiet after adjusting them cold then I would have left it at that, but they weren't and once adjusted to GMCs spec they were a lot quieter, although still an ever so slight bit tappety if the engine has been running for a long time and extremely hot, so i'd say they weren't too tight, I guess it all depends on how they've worn over the cars life.

[axsaxoman]

THE REASON WHY IT IS MORE ACCURATE TO SET THEM HOT IS THAT THE CAM IS MOUNTED IN THE ALLOY HEAD AND AS IT HEATS UP IT EXPANDS UPWARDS ,MMAKING THE CLEARANCE MORE .
I didn,t just dream this up i have been working on these engines since 1996 when we first became a citreon dealer .
If it is a blcak top type engine with no roller rockers ,then the pads which touch the top of the vlaves can ,in time wear and leave a ddepression where the valve touchs ,that means when you put a feelr blade through ti ,then you do not see the actual gap ,as the blade will go straight over the dworn part and sit on unworn parts of the rocker .
.
this was a common problem with old type engines with poor service history .
the solution is to remove the rocker gear and carefully grind the arms back to orginial shape . the called it "stoning the arms",you can replace them but at £10-£20 a pop that gets expensive
the other way to get round it is to adjust tappet clearnace by feel .

EG

you know the adjuster screw is a 1mm pitch thread ,so if you want .2mm of clearance ,loosen adjuster nut fully turn screw in till it touchs valve (no movement in rocker if you wobble it ),then turn back the adjuster screw by 0.2 of a turn .it must be correct clearance now.
it was such a problem with old engines in the sixties ,and all have adjustable tappets + pushrods in those days that a company made a special sdjusting tool to do it that way .
"SPQR" with a ratchet affair like on a micrometer ,you just tightend till it touched ,then backed it off a number of "clicks" ,it came with a list of dif cars and the no. of clicks for each engine type .

when the engine is at correct running temp then valve clearance should be correct --providing they are held open when cold it doesn,t matter what the gap is.

as to where the cam should be to set them --there is a fool proof way on ANY engine .
turn engine till valve,you are wanting to adjust is fully open ,then turn engine until the lobe s highest pint iexactly opposite to the rocker arm --it must be at its lowest point ,and therefore largest gap,there are 1-8 rules and what it says in workshop manual --but this way works on ANY engine ,and is the fall back way to do an engine of any type

[AL3X_]

I just wanted to add mate, since i've set mine to your spec, the engine has been a lot quieter :y:



when the engine is at correct running temp then valve clearance should be correct --providing they are held open when cold it doesn,t matter what the gap is.


Does this mean that say if adjusted when the car was warm, and if I check when its cold say put exhaust valve one down, and number 3 inlet 4 exhaust can both be rocked up and down then thats fine?


as to where the cam should be to set them --there is a fool proof way on ANY engine .
turn engine till valve,you are wanting to adjust is fully open ,then turn engine until the lobe s highest pint iexactly opposite to the rocker arm --it must be at its lowest point ,and therefore largest gap,there are 1-8 rules and what it says in workshop manual --but this way works on ANY engine ,and is the fall back way to do an engine of any type[/QUOTE]

This bit confuses me, I just did it like the haynes manual says, so basically I got it so the rocker arm had pushed all the way down on exhaust valve 1, then adjusted 3 inlet and 4 exhaust tappets which at this point I could rock, etc etc?

[ChAdS]

mine are set to 0.2 / 0.4 was set when engine was hot/warm ish and now there fine i just hear the noisey injectors, but to be honest the 1.6 8v are a noisey tapperly engine anyway your never going to get silent so i wouldnt worry about it!

[axsaxoman]

This bit confuses me, I just did it like the haynes manual says, so basically I got it so the rocker arm had pushed all the way down on exhaust valve 1, then adjusted 3 inlet and 4 exhaust tappets which at this point I could rock, etc etc?


I am not saying the citroen way is not close enough ,but the way i have explained will work on any engine and will be perfect ,doing it citroen way means you turn the engine less times .
now on the old cross flow ford they did it that way and the tappet gap were something like 17thou inlet and 35 thou ex ,but if you used my method or the 1-8 way then the correct clearance was 10+15 --,so doing it ford way meant that they knew that the ones you were adjusting were not right on the back of the cam ,but they allowed for it their settings --but they def ran better and stayed quieter longer doing it 1-8 rule or splitting engine in two and if outside valve was open at one end then adjust the outside one at other end -- this works for symetrical engines ,but some did not have pairs of valves . like the avenger engine --so it would not work always --.but getting valve fully open and then rotating crank by one complete turn .or untill lump on lobe is diametrically opposed to the rocker arm,or cam bucket ,if its shims works on every engine every made

[AL3X_]

Ah I kinda got it, but its still a bit confusing, basically I think i've done it right, but there is just different methods to get the right valves open at the right time to adjust yeah, different methods work for different engines but yours works for every engine possible?

Have I done it right then if the ones I was adjusting were able to rock at the time of adjusting?

As in I did it the order in the haynes manual, and for that i'll use no1 exhaust open as an example:
When the furthest towards the gearbox closes to the front of the car(no.1 exhaust valve) was fully compressed...so the rocker arm had pushed the valve down as far as it would go, then I would adjust the furthest except one towards the ECU at the back of the engine bay(no.3 inlet) and the nearest one to the ECU at the front of the car(no. 4 exhaust) and at this point these two would be movable and rock up and down with my hand...and then turned the engine to the next set, and so on and so forth?


Sorry to repeat myself i'm just getting more and more confused about the order of stuff.

[maycicek]

I have the same tappet noise problem.

last year when changing the head gasket my mechanic set the valve clearances 0.20 mm intake + 0.40 mm exhaust, whole year it was noisy.

Last week I get the valves adjusted again, I left the car whole night in the shop. Again valves were set to 0.20 mm / 0.40 mm.

At first start the engine runs perfect, but as it gets hot the tappet noise begins. When the fan of radiator begins working, the noise becomes irritating.

Tomorrow I will set them 0.20 / 0.30 mm when engine is hot as written at this topic. Thanks for the info.

[maycicek]

And I am definately sure it is not injector noise, because when the injectors not working (going downhill, gear engaged, gas pedal not pressed) there is stil the same tappeting noise.

[jage]

Everyone says to do it cold but when you think about it logically when the car is warm you will then have the noises back, ye it will be fine at cold as the clearances are good but when it warms up and expands your clearances would go all over the place!

I always set mine as GMC has stated with the cam lobe directly opposite its really easy!