Valve clearances ? how easy / difficult??

I'm no professional mechanic but a few years ago did a full set of valves (stripped cam belt) on a Fiat 1747cc twin cam engine. It's basically an Alfa 1.8 TS with just one spark plug so not a trivial piece of kit. Fitting the cylinder head involves two torque settings and two runs of 90 degree angle pulls. It really is not rocket science and no way needed an angle disc. Setting valve clearances is an entirely different job. Which at least on that engine I didn't have to do.
 
Angle torque adjuster???......had to look it up.
All these years and never had one.....I feel deprived now.
 
Well it may not be the tappets hmmm

it was clattering a good un coming home, so i popped it on the stand and went a hunting with a long

screwdriver..

I can hear the cam chain running, nice steady whir / rub noise as it runs over the guides.

The tappets sound quite quiet for tappets , but the clatter / nock / tap is still there.

I thought throttle body's at one stage, but they only make a ticking noise when i put the screwdriver

on them (injectors) .

The noise seems to be just inboard of where the rocker cover meets the head, but probing there

gives no abnormal noises.

I'll try and get a video tomorrow when i come home.

Mart
 
Well it may not be the tappets hmmm

it was clattering a good un coming home, so i popped it on the stand and went a hunting with a long

screwdriver..

I can hear the cam chain running, nice steady whir / rub noise as it runs over the guides.

The tappets sound quite quiet for tappets , but the clatter / nock / tap is still there.

I thought throttle body's at one stage, but they only make a ticking noise when i put the screwdriver

on them (injectors) .

The noise seems to be just inboard of where the rocker cover meets the head, but probing there

gives no abnormal noises.

I'll try and get a video tomorrow when i come home.

Mart

Is the clatter there while in motion or just at tickover?
Does it knock in time with the revs (increase in frequency as the revs rise)?
 
Is the clatter there while in motion or just at tickover?
Does it knock in time with the revs (increase in frequency as the revs rise)?

That's got me thinking ... I'll confirm tomorrow when I'm next out on it..

I may be wrong, but it did seem to diminish when the engine is under load, ie accelerating, then comes back at low revs / idle

but that could be that the general engine / exhaust note masks the noise.

Blipping the throttle the noise is there but I'm trying to think if it was speed dependant i was more focused on finding the noise.

I'll try to get a vid done tomorrow

mart
 
Put it in neutral and pull the clutch lever. If the noise goes off with clutch pulled in you have a gearbox input shaft end float issue.


Sent somehow.
 
If your bike is a GSA with foglights, check the foglight bodies aren't rattling against the crash bars. They can rattle like a top end noise if touching.
 
And if you can't do 180 degrees with a standard spanner then it's not the job for you.


You cannot accurately angle torque four individual nuts 180 degrees with a standard spanner...end of... not surprisingly that is why they use angle meters.

I think you've over complicated trying to estimate 180 degrees :D

Here's the first lesson for beginners . Flip the spanner arm over and you'll know exactly where it has to end up when you've reached 180 degrees.. And go. :D

 
If your bike is a GSA with foglights, check the foglight bodies aren't rattling against the crash bars. They can rattle like a top end noise if touching.

No fogs - yet ;).. will do the video on the way home tonight


mart
 
Ok home and video's done

First it start-up from cold

<iframe width="560" height="315" src="https://www.youtube.com/embed/8TVxBm0H6oA" frameborder="0" allowfullscreen></iframe>

2nd is when i arrived home

Engine nicely warm

<iframe width="560" height="315" src="https://www.youtube.com/embed/9vYWln0Szow" frameborder="0" allowfullscreen></iframe>


Mart
 
Doesn't sound too good in either vid!
Not trying to be humorous so please don't be offended.
Certainly doesn't sound like mine, I do my own valve check and adjustments finishing with throttle balancing. Any chance this could be timing chain slap mixed with some generous valve clearances?

Been reading the thread on and off but can't remember if you've attempted adjustment yet, I got a bit lost amongst the discussion over how to use a feeler....

Do you have some feelers? I could post you my set to use if required, I need to put an order in for some more sets soon but they seem to be in short supply at Wurth ATM
 
Doesn't sound too good in either vid!
Not trying to be humorous so please don't be offended.
Certainly doesn't sound like mine, I do my own valve check and adjustments finishing with throttle balancing. Any chance this could be timing chain slap mixed with some generous valve clearances?

Been reading the thread on and off but can't remember if you've attempted adjustment yet, I got a bit lost amongst the discussion over how to use a feeler....

Do you have some feelers? I could post you my set to use if required, I need to put an order in for some more sets soon but they seem to be in short supply at Wurth ATM

Dont worry, not offended :)

Agree it sounds like a bag of spanners , ( mind you, have you heard the M3 at tickover lol)

I think the way forward is covers off, and see what horrors await underneath!

Thank you for the kind offer of your feeler gauges,

I have them added to the "i need" list, along with a few other bits ;).

I guess there's not much more i can do until i get the covers off.

Mart
 
Did you adjust them by much? I suspect you have adjusted the pair that were rocking and not the firing cylinder
 
Take the rocker cover off. All tappets should have adjusters and nuts.

Turn engine to compression stroke all valves should be shut. There should be no visible gap between any tappet and valve stem. The rockers should have a slight movement when valves are shut.
That's a rough check but should tell you if there are clearances on both pairs of valves.

Any obvious movement of the rocker with valves shut is not good. No movement at all suggests there is no clearance on at least one valve. Also not good.
If you have feeler gauges you can check the clearances.
 
Listening to both vids it could be valve clearances perhaps a lock nut has come loose?
I would check the cam chain tensioner is working correctly as well.
 


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