Smooth timing = less power? Huh?

[AlleyNiki]

Hi everyone out there in Fiat Land!

Recently I did a lot of adjusting to try and reduce engine noise / rumble. New mounts etc, adding rubber spacers between that cross bar and all that.

It's still not perfect, and I think to be honest the engine timing needs adjustment because on idle the little motor vibrates up and down - sending it through the rest of the car - and it's DAMN hard to start after stopping the motor for a few minutes when it's hot.

My neighbour who is an engine nut says it isn't vibrating that badly, but adjusting the timing MIGHT cause the engine to run smoother but with less power.

What do other people think? Smoother timing causes less power? Is this right? He's not a Fiat expert..

A strobe shows that the timing pulley mark is roughly on the engine mark, but it jumps about a bit.. And some reckon these marks are not terribly accurate.. 

-Hope you guys can give some insight!
Alastair.

[Rusty's Uncle]

I think that the marks are generaly accurate but getting a good straight view on them with the back panel in position is very difficult. I recently used a small mirror along with a strobe and I reckon my previous setting was about 5 degrees out. The engine now runs pretty smoothly 

[AlleyNiki]

I think that the marks are generaly accurate but getting a good straight view on them with the back panel in position is very difficult. I recently used a small mirror along with a strobe and I reckon my previous setting was about 5 degrees out. The engine now runs pretty smoothly 

Thanks for the prompt response, Rusty. I'm sure many threads have covered it already, but isn't there a way to set up your own marks with a fine crayon using the tdc position of piston no 1?

[Rusty's Uncle]

On one of my engines I took a 1" nail bent the tip round like a pointer then super glued it to the timing chain cover at the 10 degrees before top dead centre position . Highlighted the tip of the nail and the notch on the crankshaft pulley with Tipex correction fluid and it worked really well till the super glue turned out not to be so super 
Think there is a picture on here somewhere. My thinking is the same as yours though, all you need is a couple of accurate marks when the engine is at TDC in a more accessable position and life would be so much easier . I was looking at the space to the left of the engine mount possibly with a pointer located on one of the timing chain cover bolts.

[bis13]

when you say the engine bounces around a lot is this when at idle? as i have seen this when the idle has been set too slow. if the engine mount spring is cracked it will also send vibrations through the car and if you try placing anything in between the engine mount spring (like a piece of rubber) it will also send vibrations through the car.
   

[AlleyNiki]

when you say the engine bounces around a lot is this when at idle? as i have seen this when the idle has been set too slow. if the engine mount spring is cracked it will also send vibrations through the car and if you try placing anything in between the engine mount spring (like a piece of rubber) it will also send vibrations through the car.
   

You can feel it vibrating through the car at a few different rev ranges, on idle it's noticeable but then when I'm travelling at say 50kph in 3rd, the rear view mirror is  blurred, so I don't think it's the idle. My neighbour mentioned the same thing , but when he saw it idling he thought it wasn't that low.

Also, i've used a new spring and my old original one, and there's no difference. The rubber that I put in was a thin sheet in between the main bracing at the back where it bolts on to the car (I lost the original gasket sheeting, somehow)

[AlleyNiki]

OK, this is not right! 

I got a strobe and hooked it up. Just before this I also noted that TDC of piston 1 was pretty well where the book said it was, the lower bump on the timing cover. (I removed the spark plugs and used an old paint brush handle to find out where the apex/top was)

On idle the timing notch apparently is not at 10 BTDC, but about a centimetre away from it beyond the last mark on the left - indicating it's about 30 degrees BTDC??

I'm not sure why the engine is even running like this!

Then, I marked the original position of the dizzy, and tried retarding the ignition to about 10 BTDC - the motor would barely run..

Advancing it even further made it run a fair bit faster - and a bit smoother. I locked the dizzy in this position (about 3.5 mm from its original position) and went for a drive.

The car handled OK, I suppose. The engine was a bit more responsive but I had a fair noise coming from the tappets - rattling like anything when I put my foot down. I'm not certain but I think I noticed a torque loss travelling up a steep hill..

So I can't figure out why it's running this way, with the timing so far out..

I'm starting to think my original idling speed is too low.. I have no idea what 800 rpm is meant to sound like...

Any ideas?

[smallcox]

WARNING

Advancing it even further made it run a fair bit faster - and a bit smoother. I locked the dizzy in this position (about 3.5 mm from its original position) and went for a drive.

The car handled OK, I suppose. The engine was a bit more responsive but I had a fair noise coming from the tappets - rattling like anything when I put my foot down.

Hello all,

This noise you describe sound like to much advance and will destroy engines Pinking/detonation, this will at least loss power at worst eat pistons/cylinder heads.

If your car has a waste spark coil then I have mentioned on here before that when a strobe is connected will give not true readings, ie some one told me my car was running 72 degrees advance-ok

If your happy with your basic ingnition system plugs/leads and distributor not got broken internals spring/weights and its not stuck then you can static-ly time it in if points are still used. these engines can run a couple off degress out with out to much problems.

I personnal set the ingintion static the go out for a run and keep advancining a degree until pre ingnition sets in then back off 2-3 degress for a safe margin. As for smooth running if as mentioned your idle is about 900rpm then maybe a mechanical fault or assembly problem. does the vibration get better or worse under deacceleration/acceleration?

regards Smallcox

[AlleyNiki]

WARNING

Hello all,

This noise you describe sound like to much advance and will destroy engines Pinking/detonation, this will at least loss power at worst eat pistons/cylinder heads.

If your car has a waste spark coil then I have mentioned on here before that when a strobe is connected will give not true readings, ie some one told me my car was running 72 degrees advance-ok

If your happy with your basic ingnition system plugs/leads and distributor not got broken internals spring/weights and its not stuck then you can static-ly time it in if points are still used. these engines can run a couple off degress out with out to much problems.

I personnal set the ingintion static the go out for a run and keep advancining a degree until pre ingnition sets in then back off 2-3 degress for a safe margin. As for smooth running if as mentioned your idle is about 900rpm then maybe a mechanical fault or assembly problem. does the vibration get better or worse under deacceleration/acceleration?

regards Smallcox

Hi Smallcox,

Just so you know, I returned the dizzy to nearly the original position. The pinking wasn't really bad but I didn't much like it, so I opted to wind it back. 

I have an ignition where one HT lead goes from the coil to the diz, and the diz has two more leads which work the spark plugs. That isn't the wasted spark type is it?

On idle I think the engine sits at about 600. But that's from listening to it, and I have never measured it with an external tach.

The vibration doesn't exactly get worse under acceleration, it kind of just stays the same. It's just a nuisance as it's a bit noisy to drive and I keep getting pre ignition and difficult hot starts..

Thanks for the advice, though if anyone can tell me why there's too much advance that'd be great!

Also, cylinder two shows up under the strobe as being a few degrees to the left of cylinder 1.. Don't know if that should be!

[AlleyNiki]

OK, just to let you guys know,

I did another timing procedure but a static one. Took off rocker cover, found point where all the valves were up and rotated the diz to just where the gap was opening, and guess what - it's pretty much where the diz was originally, give half a mm towards the advance direction..

So I guess my issue isn't timing. Probably.

Who knows why the strobe was showing up so far to the left.. maybe just an anomaly on the timing cover?

I think the problem may be due to my "new" clutch assy. I'll take it off and put the old one back, see if that improves things...

Thanks for the help guys

Alastair

[bis13]

you say new clutch? perhaps its not centered/aligned correctly and that is where the vibration is coming from?

[AlleyNiki]

you say new clutch? perhaps its not centered/aligned correctly and that is where the vibration is coming from?

Embarassingly, this new clutch is about 5 months old now. The vibrations started about then, but I replaced a number of things as well such as the main shaft rear bearing seal and all the engine mounts.. Thought it was a matter of the engine 'settling in'.

What do I do if the clutch isn't aligned correctly? 

Alastair

[Pete126]

There's no way the clutch plate/cover can be misaligned because the engine and gearbox would not bolt together, Its more likely to be the alignment of the engine/gearbox to the car body. when i have taken engine/gearboxes out I draw round the gearbox mounts so it goes back in the same position.