To adjust hot or cold?

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Hammo - 27 Apr 2007 10:57 GMT

Continuing on with a thread that disappeared somewhere...

OK, Teggers was pointing out that valve lash should be adjusted when cold.
This has how I have undertaken it on several motorcycles as getting it to
temp with the cams out, tank off etc to get at the shims is impossible
(though insert advances in "special tools here).

The 4AC needs an inspection (one of those I've been putting off things) and
am quite happy to adjust when cold. Will the earth and the moon require the
interaction of McGyver to untangle the evil that may be unleashed if I do it
this way?

If not, why is it that all the Australian Spec manuals have "get car to
operating temp, t(h)en burn fingers adjusting valves?

Cheers

Hammo

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Ph@Boy - 27 Apr 2007 14:44 GMT

> Continuing on with a thread that disappeared somewhere...
>
[quoted text clipped - 14 lines]
>
> Hammo

Like I mentioned before Hammo, the manual will dictate the procedure.
Adjusting valves on sport bikes requires cam removal due to component
size and the amount of room allowing shim adjustment. It's just too darn
tight in there to do anything! Tank off, air box, hoses, etc,. I know on
a bike it's not a fun job but that's how it has to be done, and the
manufacturer plans for it. Fortunately, valve lash adjustments on most
sport bikes are quite lengthy between intervals. A car allows much more
room and the components are far larger. Do it the way the manuals say to
IMHO.

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hammo@ihug.com.au - 27 Apr 2007 15:28 GMT

> > Continuing on with a thread that disappeared somewhere...

[snip duplicate]

> Like I mentioned before Hammo, the manual will dictate the procedure.
> Adjusting valves on sport bikes requires cam removal due to component
[quoted text clipped - 5 lines]
> room and the components are far larger. Do it the way the manuals say to
> IMHO.

Damn vanishing and then reappearing posts!

The Kwakka ZX1100A2 was one of my bikes that required all that
stuffing about (early - mid 80's DOHC central tunnel cam chain with
tappet cover as part of te tensioning body).

I agree with what you were say about the manual, though was interested
when Teggers said he had never seen it written to adjust valves hot on
the (mighty) 4AC.

I was going to measure the lash cold and compare when hot and then
guestimate what to do for next time (this being a newish motor).

Thanksfor the replies. Oh, I had to swap the old carby for this motor
as whatever was on there had two fuel sonoids and pollution/vac hoses
that didn't line up with any of the pics yourself and other posters
scanned/posted. Strange world..

Cheers

Hammo

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Slim Pickings - 28 Apr 2007 22:50 GMT

>> > Continuing on with a thread that disappeared somewhere...
>>
[quoted text clipped - 9 lines]
>> room and the components are far larger. Do it the way the manuals say to
>> IMHO.

On the current 4 cyl Camry engine 2AZ-FE, Toyota manual say
to adjust cold. As this engine uses shimless type lifters it
would be difficult to keep the engine hot while removing the
valve cover and making the sixteen measurements neccesary
before making any lifter changes. Toyota knows how much the
vave expands when hot so its not a big deal to supply a COLD
spec.

Intake 0.19 - 0.29 mm (0.0075 - 0.0114 in.)

Exhaust 0.30 - 0.40 mm (0.0118 - 0.0157 in.)

I am more surprised by the 0.1 mm tolerance allowed.

Slim

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