Technical Valve clearances

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Technical Valve clearances

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Hi Folks,

My 2012 1.2 8v panda Lounge is soon to be 3 years old and its already on 37k. In the handbook it says at 36k the valve clearances are to be checked. I would usually have a go at this sort of stuff by myself but I haven't had the time recently. Anyway I’ve had them checked by the local fiat dealer (Clemo) and they have come back as follows:

Inlet valves
2 - 0.3mm 4 – 0.3mm 5 – 0.3mm 7 – 0.3mm

Exhaust valves
1 - 0.4mm 3 - 0.4mm 6 - 0.415mm 8 – 0.43mm

According to the information Clemo gave me the inlet should be 0.3mm +/- .01mm and the exhaust valves 0.4mm +/- .01mm. However, I also have a Haynes manual and that says inlet valves should 0.35 +/- 0.05mm and exhaust 0.45mm +/- 0.05mm.

I've have had a spot of bother before with clearances being tight (being told by a garage they are fine!) and valves burning. I’m keen to avoid the same happening again.

I feel there is reluctance by garages to check them, even though they are essential to engine life and correct functioning.

What I would like to know is, are the above figures okay?

Will they be fine for another 36k till the next check?

Which figures are correct, the ones Fiat have given me or the Haynes manual?

Also, in future, should I tackle the job by myself, how hard is it to get the shims out and what tools do I require?

Many thanks,
Adam
 
Although the Haynes Manuals occasionally do have errors, in this instance I am sure they are correct.
0.01mm is smaller than the absolute accuracy of a digital caliper, this is far too small.

Only if the valve clearance is well out of tolerance should they be adjusted, and if they need much adjustment then there is an underlying problem that needs attention.

I must have done at least 80,000 miles in 1.2 8v Puntos and have never checked the valve clearances, best to leave them alone. My 99,000 miles MJ has never had the valve clearances checked, just regular oil changes with a Fiat filter and full synthetic oil.
 
ImageUploadedByFIAT Forum1422530798.300800.jpg I've managed to purchase the tool from Fiat, I will now be able to do the job in the future by myself
 
Are we talking bucket and shims here? Having to remove the camshafts to get to them.

What exactly is that Fiat tool for then??
 
Are we talking bucket and shims here? Having to remove the camshafts to get to them.

What exactly is that Fiat tool for then??
It lets you do the shims without removing the cam! The curved end of the tool slips under the cam and bears upon the very edge of the follower - bucket as you call it - (not on the shim) then you push down on the handle which forces the curved end in under the cam and it depresses the cam follower against it's spring opening up a gap between the cam (which, of course, you have rotated until the lobe is pointing up - away from the follower) and follower. Now you can winkle out the shim and replace it with the one you need. Simples!

I've only used one once, years ago on a 128. I seem to remember it worked very well and saved loads of time but the edge of the tool which bears on the thin edge of the "bucket" looked quite worn - I borrowed it from a friend who worked in a Fiat garage so it probably saw a lot of action. I must say though that I've never had to adjust any of the several Fiats we've had in the family (mind you I do oil changes religiously and use top quality oil) and don't hear any tap, tap, tapping away as others go past in the street. Our 1.2 Panda, at 63,000 miles and my boy's 1.4 8 valve Punto, with just over 50,000 miles on it are whisper quiet in this respect. They do "rattle" for a couple of seconds though if left without starting for a few days. This, I'm sure, will be due to the oil supply just taking these few seconds to flood back over the cam and followers from the small spray holes in the cam cover. If used every day neither car does this.
 
Shimmed valve engines do keep their clearances for a long time, hydraulic are good but I've heard of them "pumping" up if the engines are neglected. There were a few engines around over the years with shimmed OHC valves, even the Imp had this set up, snag is they needed head gaskets more often than a valve clearance check.
 
It lets you do the shims without removing the cam! The curved end of the tool slips under the cam and bears upon the very edge of the follower - bucket as you call it - (not on the shim) then you push down on the handle which forces the curved end in under the cam and it depresses the cam follower against it's spring opening up a gap between the cam (which, of course, you have rotated until the lobe is pointing up - away from the follower) and follower. Now you can winkle out the shim and replace it with the one you need. Simples!

I've only used one once, years ago on a 128. I seem to remember it worked very well and saved loads of time but the edge of the tool which bears on the thin edge of the "bucket" looked quite worn - I borrowed it from a friend who worked in a Fiat garage so it probably saw a lot of action. I must say though that I've never had to adjust any of the several Fiats we've had in the family (mind you I do oil changes religiously and use top quality oil) and don't hear any tap, tap, tapping away as others go past in the street. Our 1.2 Panda, at 63,000 miles and my boy's 1.4 8 valve Punto, with just over 50,000 miles on it are whisper quiet in this respect. They do "rattle" for a couple of seconds though if left without starting for a few days. This, I'm sure, will be due to the oil supply just taking these few seconds to flood back over the cam and followers from the small spray holes in the cam cover. If used every day neither car does this.

Many thanks, understood, I assumed that the shim were contained within/under the bucket as such,.....my motorcycle engine is like that so the camshafts will have to be removed sadly.

I wonder how much Fiat want for that tool.:)
 
Yes, I've heard that too but what's the theory behind it, do you know?

OHV engines had pushrods and adjustable rockers that had their own shaft, all wear points that changes clearances. There is little that can wear on shimmed OHC engines so long as oil and filter changes are done in a timely manner. No doubt why they stay well within spec for many miles.
 
I assumed that the shim were contained within/under the bucket as such,.....my motorcycle engine is like that so the camshafts will have to be removed sadly.

I wonder how much Fiat want for that tool.:)

Yup, probably a more common way of doing it. The old "O" and "E" series BL engines were like that. Used to "stick" them in place on the cam follower with a little dab of Vaseline to stop them falling out during assembly. Borg Warner used to advise using Vaseline when building up their auto boxes because when it gets hot the Vaseline will melt and become emulsified into the gearbox oil so no danger of blocking any oilways/servo's etc (as grease would do).

No idea what the tool costs, but if you are careful it can be done with the side of a screwdriver.

If you are going to do this yourself measure the clearance with feelers and write them all down as you go. Unless you are very unlucky they won't all be outside tolerance. For an everyday road going engine within tolerance is quite good enough. Don't make life hard by chasing that last "smidgeon" of clearance! Now work out how much the "wrong uns" need to be added to or, less likely, subtracted from to get the right gap. If you have a clearance that has closed up it may be due to valve seat erosion. You'll need to firstly check for leakage past the seat (cylinder leak test) and if you get a poor reading the head will need to come off. Now winkle out the existing shim, turn it over and the thickness should be etched/written on it. Felicity had 2 with nothing written on them! Luckily I had a micrometer so could measure what they were - a good quality vernier caliper would do as well. So now you know the thickness of your existing shim and how much you need to change it by to get the recommended gap - a wee working out on paper will give you the shim size needed. Write it down on a piece of paper, you'll forget it if you don't. Now you've got to get hold of the thickness of shim you need. The main agent may have them if you're lucky. Often specialist independents will keep old ones for future use so are always worth a try but you may have to order them and wait for them to come. When I was younger and doing a lot of BL stuff I used to source some parts from breakers and would always have my eyes open for little "extras" as I wandered about (part stripped heads, which would be of little commercial value, were always good for shims etc - but always offer to pay for them if you intend to return to the yard later. After all not to do so is stealing and these guys need to make a living too).

Availability, or non availability, of shims was often a problem in the garages I worked in. Unless there was a really thorough storesman in charge often the shim box would be handed back to the stores but no attempt made to reorder the shims used. After some time you would find a shim box with several of one size and none of another. It was mostly BL stuff I found I had this problem with (working in BL dealerships) so I got a machine shop to make me a wee shim holder - just a length of round bar with a recession machined in the end to hold the shim - now I could find a shim slightly larger than I needed (if the one I needed wasn't in the box) and gently "kiss" it down to size on the side of a grinding wheel, then assemble it rough, ground, side to the follower. Worked a treat and cost me a fiver if I remember. My work bay was never clogged up with unfinished work so I could always make good bonus!

Finally, when you've got it all back together before you button it up and put the cam cover back on squirt a little oil over the followers and lobes, take the plugs out and spin the engine over for a few seconds. This will settle the shims into the followers. I have found, just sometimes, a shim needs this to settle properly into it's running position. if you do a final clearance check before giving it a spin, just occasionally, you'll think you've done a clearance wrong when all it actually needs is a settling down spin!
 
Yup, probably a more common way of doing it. The old "O" and "E" series BL engines were like that. Used to "stick" them in place on the cam follower with a little dab of Vaseline to stop them falling out during assembly. Borg Warner used to advise using Vaseline when building up their auto boxes because when it gets hot the Vaseline will melt and become emulsified into the gearbox oil so no danger of blocking any oilways/servo's etc (as grease would do).

No idea what the tool costs, but if you are careful it can be done with the side of a screwdriver.

If you are going to do this yourself measure the clearance with feelers and write them all down as you go. Unless you are very unlucky they won't all be outside tolerance. For an everyday road going engine within tolerance is quite good enough. Don't make life hard by chasing that last "smidgeon" of clearance! Now work out how much the "wrong uns" need to be added to or, less likely, subtracted from to get the right gap. If you have a clearance that has closed up it may be due to valve seat erosion. You'll need to firstly check for leakage past the seat (cylinder leak test) and if you get a poor reading the head will need to come off. Now winkle out the existing shim, turn it over and the thickness should be etched/written on it. Felicity had 2 with nothing written on them! Luckily I had a micrometer so could measure what they were - a good quality vernier caliper would do as well. So now you know the thickness of your existing shim and how much you need to change it by to get the recommended gap - a wee working out on paper will give you the shim size needed. Write it down on a piece of paper, you'll forget it if you don't. Now you've got to get hold of the thickness of shim you need. The main agent may have them if you're lucky. Often specialist independents will keep old ones for future use so are always worth a try but you may have to order them and wait for them to come. When I was younger and doing a lot of BL stuff I used to source some parts from breakers and would always have my eyes open for little "extras" as I wandered about (part stripped heads, which would be of little commercial value, were always good for shims etc - but always offer to pay for them if you intend to return to the yard later. After all not to do so is stealing and these guys need to make a living too).

Availability, or non availability, of shims was often a problem in the garages I worked in. Unless there was a really thorough storesman in charge often the shim box would be handed back to the stores but no attempt made to reorder the shims used. After some time you would find a shim box with several of one size and none of another. It was mostly BL stuff I found I had this problem with (working in BL dealerships) so I got a machine shop to make me a wee shim holder - just a length of round bar with a recession machined in the end to hold the shim - now I could find a shim slightly larger than I needed (if the one I needed wasn't in the box) and gently "kiss" it down to size on the side of a grinding wheel, then assemble it rough, ground, side to the follower. Worked a treat and cost me a fiver if I remember. My work bay was never clogged up with unfinished work so I could always make good bonus!

Finally, when you've got it all back together before you button it up and put the cam cover back on squirt a little oil over the followers and lobes, take the plugs out and spin the engine over for a few seconds. This will settle the shims into the followers. I have found, just sometimes, a shim needs this to settle properly into it's running position. if you do a final clearance check before giving it a spin, just occasionally, you'll think you've done a clearance wrong when all it actually needs is a settling down spin!

Thanks, lots of great advice there.:)

I'm not looking forward to doing the shims on the motorcycle, I'd like to complete the job in the same day or at least over a weekend because it's my transport to work basically.
I've been looking at buying a box of shims, still no guarantee that there will be enough, all the valves could need the exact same size. Lol

So far I've only found this supplier, cost and the shipping makes it an expensive kit though.

http://www.hotcamsinc.com/productinfo.aspx?cat_id=9
 
Thanks, lots of great advice there.:)

I'm not looking forward to doing the shims on the motorcycle, I'd like to complete the job in the same day or at least over a weekend because it's my transport to work basically.
I've been looking at buying a box of shims, still no guarantee that there will be enough, all the valves could need the exact same size. Lol

So far I've only found this supplier, cost and the shipping makes it an expensive kit though.

http://www.hotcamsinc.com/productinfo.aspx?cat_id=9
If you're doing a whole head - like after grinding in all the valves, so all the old shims will be "wrong" - You'll often find that several of the "old" shims can now be relocated to other valves where they will now be the required size! I used to find that this, together with my "baccy" tin of scrap yard shims and occasional use of the grinding wheel with my special shim holding tool would usually see me through.

Several of us kept "baccy" tins and, every now and again, we would do an exchange of sizes during a tea or lunch break. The system worked well.
 
So far I've only found this supplier, cost and the shipping makes it an expensive kit though.

Why not try asking at your machine's main agent? They may know an easy and cheap source of supply? - and maybe not, but worth a try. If you can talk to a mechanic/technician even better. Most mechanics mess about at home with "stuff" and he may either have what you want or know of a supply source.
 
Why not try asking at your machine's main agent? They may know an easy and cheap source of supply? - and maybe not, but worth a try. If you can talk to a mechanic/technician even better. Most mechanics mess about at home with "stuff" and he may either have what you want or know of a supply source.

Oh yeah they sell them, price starts at £4.50, looks like there are over 50 different sizes.

https://www.worldoftriumph.com/part...triumphmc/modelid/621910/block/100061494-3-2/
 
Oh yeah they sell them, price starts at £4.50, looks like there are over 50 different sizes.

https://www.worldoftriumph.com/part...triumphmc/modelid/621910/block/100061494-3-2/

OK. That could add up. But you may only need a couple? You won't really know until you get stuck in. (Of course, being an "old fart", I tend to think - Motor cycle? that'll be a twin then. Of course yours is more likely to have at least as many valves as the average family car these days!

Being a rather creaky "old fart" I find myself enduring various niggly bodily discomforts which are hardly noticeable during the day when I'm moving around but tend to disturb me at night when lying still for a long time. Last night was one such.

So I found myself turning over and then over again at around 6 am this morning trying to find a comfortable position. Whilst doing this I find my mind thinking about "anything and awething" and I started wondering what I'd done with my old tin of shims? So, this morning, after bringing the empty bins in, I started looking through the chaos which is my garage. I remember the tin well, it's a Condor tobacco tin, couldn't find it though. As Mrs Jock would say, "You've obviously put it in a very safe place" My house and garden is obviously over endowed with "very safe places"! It's been years since I last even handled it - it'll turn up one day when I'm looking for something else I can't find!

The first, and most obvious, place I looked was in the drawer of my tool box where I keep my "special & weird" tools. almost immediately I came across the shim holding tool I had made for me so I could grind shims. I actually had 2 (for different diameters of shim) but this is the only one in the drawer - maybe the other one is keeping the Condor tin company? Anyway I thought you might like to see it:

P1080286.JPG

You can see the recess in the end where you put the shim and then you hold it lightly against the side of a grinding wheel and "kiss" off a little metal. The black paint is optional - don't remember spilling paint on it? - In use don't let it get too hot or the shim will loose it's hardness and wear rapidly when in service. (You'll also notice how clean that hand is after two weeks of being forbidden to get "mucky" whilst Mrs J's sister was staying. She went home on Sunday so the finger nails will be back to their usual grubby state soon):

P1080284.JPG

The tool works well but does have an inherent problem - there's no way of securing the shim into the end of it! The problem this causes is that, just sometimes, the edge of the shim would pick up on the stone and be "spat out" to disappear at great speed to some place where it could "hide" so you then wasted time looking for it! Annoying at home, loosing bonus time at work. Then one day I was drifting a phosphor bronze (solid) spigot bush out of a flyweel when I had a eureka moment. I was taught to remove spigot bearings by packing them with grease and selecting a punch which is a good fit in the center of the bush, inserting it and hitting it sharply on the end with a hammer. This applies a compressive shock to the grease which, being a liquid, is not compressible so transfers the force to the bearing which, usually, obliges by jumping out of it's hole! I wondered if the reverse might be true?

By the way, if you try this hold a bit of rag round the "business end" of the punch (not the end you hit) unless the punch is an exceptionally good fit in the bush some grease usually squirts out as you hit the punch with the hammer and it's not very good for the complexion - especially if you've got to wait till home time to get a really good wash!

I packed a very small amount of HMP grease into the recess on the shim tool and placed a shim on top, then tried to remove it. By gum was that difficult! What a suction. It worked brilliantly stopping the shim being "spat out" but getting the shim out of the tool took enough time to be annoying. After a little more thought I modified the tool by drilling a small hole down the middle under where the shim fits and then a slightly larger threaded hole in the side which I made a plug for (notice the head of the set screw? Imperial thread - no metric stuff in those days).

P1080291.JPG

P1080288.JPG

P1080287.JPG

The best way to use it I found to be to pack grease into the cavity with the plug removed. Place the shim into the recess which would chase grease up the wee hole and into the threaded hole then when you screwed the plug back in there would be no air to destroy the hydraulic locking effect. To remove the shim all that was needed was to remove (actually slackening just enough to let air in was enough) the plug so the hydraulic effect was lost and the shim could be "winkled" out with a small screwdriver.

By the way, as you would imagine, this shim gets quite hot very quickly so, as previously mentioned you have to be careful not to overheat it and so destroy it's hardening - but you are only "kissing" a few thou off it so it's not a major grinding job! But you do need to use HMP grease (high melting point - wheel bearing grease will do) otherwise the grease will melt and get all over your grinding wheel and ruin it. - Guess how I know that!
 
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OK. That could add up. But you may only need a couple? You won't really know until you get stuck in. (Of course, being an "old fart", I tend to think - Motor cycle? that'll be a twin then. Of course yours is more likely to have at least as many valves as the average family car these days!

Being a rather creaky "old fart" I find myself enduring various niggly bodily discomforts which are hardly noticeable during the day when I'm moving around but tend to disturb me at night when lying still for a long time. Last night was one such.

So I found myself turning over and then over again at around 6 am this morning trying to find a comfortable position. Whilst doing this I find my mind thinking about "anything and awething" and I started wondering what I'd done with my old tin of shims? So, this morning, after bringing the empty bins in, I started looking through the chaos which is my garage. I remember the tin well, it's a Condor tobacco tin, couldn't find it though. As Mrs Jock would say, "You've obviously put it in a very safe place" My house and garden is obviously over endowed with "very safe places"! It's been years since I last even handled it - it'll turn up one day when I'm looking for something else I can't find!

The first, and most obvious, place I looked was in the drawer of my tool box where I keep my "special & weird" tools. almost immediately I came across the shim holding tool I had made for me so I could grind shims. I actually had 2 (for different diameters of shim) but this is the only one in the drawer - maybe the other one is keeping the Condor tin company? Anyway I thought you might like to see it:

View attachment 198612

You can see the recess in the end where you put the shim and then you hold it lightly against the side of a grinding wheel and "kiss" off a little metal. The black paint is optional - don't remember spilling paint on it? - In use don't let it get too hot or the shim will loose it's hardness and wear rapidly when in service. (You'll also notice how clean that hand is after two weeks of being forbidden to get "mucky" whilst Mrs J's sister was staying. She went home on Sunday so the finger nails will be back to their usual grubby state soon):

View attachment 198613

The tool works well but does have an inherent problem - there's no way of securing the shim into the end of it! The problem this causes is that, just sometimes, the edge of the shim would pick up on the stone and be "spat out" to disappear at great speed to some place where it could "hide" so you then wasted time looking for it! Annoying at home, loosing bonus time at work. Then one day I was drifting a phosphor bronze (solid) spigot bush out of a flyweel when I had a eureka moment. I was taught to remove spigot bearings by packing them with grease and selecting a punch which is a good fit in the center of the bush, inserting it and hitting it sharply on the end with a hammer. This applies a compressive shock to the grease which, being a liquid, is not compressible so transfers the force to the bearing which, usually, obliges by jumping out of it's hole! I wondered if the reverse might be true?

By the way, if you try this hold a bit of rag round the "business end" of the punch (not the end you hit) unless the punch is an exceptionally good fit in the bush some grease usually squirts out as you hit the punch with the hammer and it's not very good for the complexion - especially if you've got to wait till home time to get a really good wash!

I packed a very small amount of HMP grease into the recess on the shim tool and placed a shim on top, then tried to remove it. By gum was that difficult! What a suction. It worked brilliantly stopping the shim being "spat out" but getting the shim out of the tool took enough time to be annoying. After a little more thought I modified the tool by drilling a small hole down the middle under where the shim fits and then a slightly larger threaded hole in the side which I made a plug for (notice the head of the set screw? Imperial thread - no metric stuff in those days).

View attachment 198614

View attachment 198615

View attachment 198616

The best way to use it I found to be to pack grease into the cavity with the plug removed. Place the shim into the recess which would chase grease up the wee hole and into the threaded hole then when you screwed the plug back in there would be no air to destroy the hydraulic locking effect. To remove the shim all that was needed was to remove (actually slackening just enough to let air in was enough) the plug so the hydraulic effect was lost and the shim could be "winkled" out with a small screwdriver.

By the way, as you would imagine, this shim gets quite hot very quickly so, as previously mentioned you have to be careful not to overheat it and so destroy it's hardening - but you are only "kissing" a few thou off it so it's not a major grinding job! But you do need to use HMP grease (high melting point - wheel bearing grease will do) otherwise the grease will melt and get all over your grinding wheel and ruin it. - Guess how I know that!

The bike in question has 3 cylinders, 4 valves per pot so 12 shims in total but you are right, chances of having to replace all of them are slim, I hope.:)

Thanks for all the tips, I love to see pictures of home made tools/what people come up with to solve problems,....my first thought were to recess a magnet in the end of that tool, maybe a rare earth one would be strong enough to keep a shim in place whilst at the grinder? Possibly need an hole in the middle of the magnet/the whole thing to be able to poke out the shim when you are done.
 
3 cylinders? Not a Triumph is it? I shared a 350 twin, with my flatmate, back in the '60's - until he fell off it on a roundabout. The 'bike, unfortunately suffered frame damage as it collided with a concrete reinforcement. My friend, luckily, missed it and slid down the road for quite some distance on his backside - didn't do his jeans, or backside, any good at all and left me without transport!
 
Oh, and I like the magnet idea! Didn't cross my mind all those years ago and I don't know if you could get very strong (neodynium - or a name something like that?) ones in those days? I really lament the passing of Maplins for "stuff" like this. Don't you?

The tool I showed you definitely did "O" series (I worked a lot on Princess, Ambassador and Marina at that time. The engine turned up in vans too) and I think "E" series engines. Trying to remember why I made the other tool (the one I think is keeping the Condor tin company some where in the deepest darkest depths of my garage). I think it was for doing the "straight" engines in the SD1? When they were selling in some quantity we always seemed to have one in the workshop with it's head off!
 
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