Technical valve adjustment tricky?

[irc]

jrkitching absolutely right about small independent garages not having loads of shims in stock.
Although they do tend to be the ones who CAN actually do the job. Most of the non-franchise big garages don't really want the work, and I suspect many wouldn't know how anyway.

My friendly local mechanic tends to have only a few, but he normally arranges to get the car in for service overnight, then does service including checking clearances etc.
If they need work he arranges to get the car back overnight again sometime in the next few weeks, and orders in the shims.
Apparently he gets them on sale or return anyway, so not a big deal for him.

I usually do my own, and I've only got about 20 spare shims, nearly all of which have been used. Some probably have been used more than once. As long as the ones I take out are not worn, they go straight back in the jar for next time after measuring.

Individual shims are cheap enough if you are only buying a few at a time, but a box of assorted ones can easily be £300 or so.

 

[ruinin]

As for the "cold engine", I found a guy who says he can easily check the clearances and does his own with his Punto and he says that only if the clearances are way off, any adjusting is necessary. Of course, by "way off", I don't know what he means specifically.

He says it is a-few-minute job. I just don't know if cold engine means it is only cold after several hours? It doesn't get cold enough within an hour or so? Even if the temperature outside is near freezing?

I would let him check the clearances but it would have to be a quick visit and I cannot leave the car there overnight.

But it seems I am getting closer to finding someone who can at least check that the clearances are OK. I still hope they are.

 

[Thefox]

Go to a fiat garage.
If your in North Yorkshire I will do it for you. No charge.!
It's an easy job and it's part of the service schedule, it should be done every other service.

 

[jrkitching]

It doesn't get cold enough within an hour or so? Even if the temperature outside is near freezing?

No, the engine is a large lump of metal which will not cool to a uniform temperature in an hour or so. It's best to let it cool overnight before checking valve clearances.

Setting the valves when the engine is partially warm could result in having insufficient clearance; not a good idea.

 

[ruinin]

Go to a fiat garage.
If your in North Yorkshire I will do it for you. No charge.!
It's an easy job and it's part of the service schedule, it should be done every other service.

that's the mystery, a mechanic from an authorised fiat garage in Prague told me that it is super expensive and nobody asks them to do it

 

[ruinin]

No, the engine is a large lump of metal which will not cool to a uniform temperature in an hour or so. It's best to let it cool overnight before checking valve clearances.

Setting the valves when the engine is partially warm could result in having insufficient clearance; not a good idea.

I see, so it has to be agreed on that I leave the car there overnight.

 

[Thefox]

If the garage says it's tricky and expensive then they don't know what they're doing.

 

[DaveMcT]

The job is fiddly but not especially technical. The last one I did was a double over head cam bike. The angled valves made it more awkward - the shims fell out too easily while refitting.

Turn the cam so the lobe is pointing away from the valve, measure clearance between cam follower and cam record them all. Swap the shims about so that all are within limits then you may only need to buy one or two new shims.

Turn the engine on the starter and recheck the clearances all should be correct.

If you are really fussy fit the cover and start the engine. then allow to cool and check again. But this would be at the OCD end of the scale.

Expect the engine to sound a bit more tappety with correct clearances at the wide end of the range.

 

[bluejohn125]

I'm sure most owners and garages just ignore this requirement for the 8V FIRE engines, even though millions have been made for Unos, Cinqs/Seis, Pandas and Puntos.

The procedure is the same as for other earlier SOHC Fiat engines (like my Tipo), there is a special forked Fiat tool that will allow you to press 2 adjacent valve springs doen and pop out the shims. Anyone can check the clearances on a COLD engine, if you think it through you can check 2 valves on diferent cylinders (1 inlet 1 exhaust) at the same time once you've rotated the engine to a "closed" position. You note each of the 8 clearances, and compare with the allowed ranges for inlet and exhaust. If any are out of tolerance then remove the shim, measure it (or read the marking on it) and work out what shim thickness should be inserted to get the clearance in range.

You can then come back later and give the incorrect valves some attention, or remove the faulty shims, calculate the required replacements, and order and fit them as soon as you can.

 

[varesecrazy]

Oh well, oh well, I just called a garage that had excellent references as for Fiat servicing. I asked about their capability to do the valve adjustment and the mechanic told me that he tried to do that with his motorbike and failed and that the job is extremely tricky, that it is basically impossible to get the clearances right as you measure something when the engine is cold, then you finish the job and start the engine and the hot engine has different clearances from what it was when it was cold. He told me that most probably all mechanics will mess up this job and it would be better to leave it as it is and not mess up with the clearances at all. He said as long as there are no wrong noises, I am fine and as for burnt valves he said the cause is different and not caused by wrong clearances.

I remember a friend going into a Yamaha main dealer, attempting to buy some replacement shims, (SIMILAR arrangement to a FIRE)

"we don't stock them - and never have" came their reply..

makes you wonder how they've ever serviced an engine doesn't it..

 

[DaveMcT]

I remember a friend going into a Yamaha main dealer, attempting to buy some replacement shims, (SIMILAR arrangement to a FIRE)

"we don't stock them - and never have" came their reply..

makes you wonder how they've ever serviced an engine doesn't it..

Some years ago I looked at buying a Honda VFR 750. Reliable, fast, acceptable on fuel and good for long commuting runs. However I was likely to be doing 15K to 20K a year so would need the warranty. The dealer said it would cost an additional £500 every 15K to have the valve clearances checked and even more if any needed to be changed. Not doing the check would void the warranty.

I asked how often they needed to change shims. "We never have" came the answer. So checking at such a short interval is make work for Honda? No answer available.

I walked away and bought a Yamaha Diversion 900 that did 70K before it needed one exhaust valve shim.

 

[ruinin]

Some years ago I looked at buying a Honda VFR 750. Reliable, fast, acceptable on fuel and good for long commuting runs. However I was likely to be doing 15K to 20K a year so would need the warranty. The dealer said it would cost an additional £500 every 15K to have the valve clearances checked and even more if any needed to be changed. Not doing the check would void the warranty.

I asked how often they needed to change shims. "We never have" came the answer. So checking at such a short interval is make work for Honda? No answer available.

I walked away and bought a Yamaha Diversion 900 that did 70K before it needed one exhaust valve shim.

So that makes Honda and Fiat two bizarre engine maintanence strategies... in my book of regular Fiat service in the authorised garage it says clearances are checked every 40 000 km, but I have never got a huge bill for that job, so I guess they never checked the clearances or they only had a quick look and charged nothing... I think I will call again and ask them "How much is the checking without adjustment? As you obviously had done that a few times with my car already"... and never charged me anything that would raise my eyebrows, as far as I remember a regular yearly service including oil change and checking clearances was never more than about the equivalent of 100 pounds. I dont want them to check it, as I don't believe tham, just want to make them give me a decent answer. They will probably tell me things like it is cheaper when part of the whole yearly job... and that my clearances must have been OK.

 

[g8rpi]

I checked the service history of a car once and found a worksheet that was clearly ticked for "change spark plugs". The car was a diesel and there was a tick box for N/A on the sheet.

Robert G8RPI.

 

[DaveMcT]

Valve seats will regress over time. Shims only have to be changed when the clearance goes below minimum. This allows for the valves to expand and still retain a clearance

Petrol engines (higher exhaust temperatures, stronger valve springs, higher revs) should be checked more frequently than diesels. My issue with Honda was the cost due to poor access and the excessive frequency.

The FIRE 8 valve is probably one of the easiest to check after a BL A-Series. Lift the cam cover and there it is. 10 minutes to feeler gauge the gaps and box it up again. Add an hour if the shims need to be rearranged or changed.

 

[jrkitching]

"How much is the checking without adjustment?"

The work is essentially the same regardless of whether adjustment is needed, so I'd expect checking with adjustment to be the same price, plus the cost of any shims required (perhaps a few euros each).

My guess is it's never been done before on your car.

They don't often need changing, and when they do, it's almost always just the exhaust valves.

The FIRE 8 valve is probably one of the easiest to check after a BL A-Series. Lift the cam cover and there it is.

Easiest one I've ever done is the Ford Endura-E engine used in the earlier Ka's; no locknut and a single spanner adjustment that can be done in less than 5 seconds with one hand. Just as well, since they did need checking (and very often adjusting) every 12k and the engines were tappety even when they were correctly set - you started worrying if they went quiet.

The 8V FIRE generally stays in adjustment and on a normally driven car, I'd leave checking until cambelt change time, when it's an easy add-on job.