Checking my static timing

[Johnny69]

Okay I'd really appreciate some help with this.

I'm trying to work out where the timing has been set on my early bay. It's a 1600 twin port engine with a vac advance dizzy. Its starting snd running but i want the timing checking. Anyway I've got no faith that the dizzy is installed correctly so I'm trying to find top dead centre and am trying to check this by making sure that number 2 exhaust valve is rocking - there's a video on youtube showing how to do this and the guy gives it a push and it rocks back and forth.

Problem is no matter where I seem to position the pulley I can't get number 2 rocking at all!! The valve goes in and out when the pulley is moved around but for the life of me I can't get 4 exhaust rocking by pushing it as shown on the youtube clip.

Anyone got any ideas? :|

Cheers

Johnny

 

[BJ1]

Forget about youtube clips - they are mostly bollocks.

You should be looking for TDC on No 1 cylinder on the firing stroke. You find this by using this method http://www.aircooledtech.com/timing/static/ You can also find tdc by slowly turning engine with no 1 plug out and a wooden dowel touching the piston top. When dowel is at max height and BOTH valves are loose (ie rock) then piston is at TDC on firing stroke. Remember there are two tdcs on each cylinder on a four stroke engine, one is the firing stroke, the other the intake/exhaust stroke. Then follow instructions on the link above.

When engine is running smoothly on static timing you are ready to do it properly. Use a timing gun and set the timing to 28 degrees BTDC at around 3500rpm. That's the critical engine speed - where you are driving most of the time. The timing at idle is not important. Timing it with a gun checks that your advance mech is working properly - if it isn't then sooner or later you will cook the engine.

Oh yes - go and buy a Haynes and/or Bentley manual if you don't already have one, and sort your valve clearances before you time the engine.

 

[Johnny69]

Cheers ill try that.

So when you say the valves rock do you mean you can push them in/ out and they rock in and out?

Tks

johnny

 

[jonboylaw]

Not the valves, but the rockers should be able to be wobbled by hand. This means they are loose, hence both valves closed and on the firing stroke.
Follow the advice above, it is all sound.


Sent from my GX64 SatCom phone using Tapatalk

 

[sharky71]

does finding the firing stroke matter??
I was told/led to believe if you can rotate both pushrods on each cylinder freely(tdc line matching case seam for the cylinder you want to check) then the valves are closed and you were able to check the clearances? is this correct? :roll: :? :shock:

 

[Johnny69]

Okay, I've done the stuff with the pencil and checked the valves are in the right place. So.....I have number one cylinder at top dead centre - I'm confident that it is at tdc. When I check the dizzy, the dizzy arm is pointing to just before number 3 spark plug lead. So the firing order I've got with number 1 at top dead centre 3214

It looks like the dizzy has been installed 180 degrees out so I reckon I can either rotate the dizzy or swap the plug leads round now I've got tdc on number 1 and........hope it still starts.

How does the engine run at all with this setup???????

Cheers

Johnny

 

[sharky71]

are you sure you are tdc on the fire stoke as said before?
I had a element of doubt on what I did previous so I took out plug 1 put in tent peg,took dissy top off took valve cover off and set timing mark on pulley wheel to match case seam.
noted rota arm was pointing at lead/cylinder 1 then rotated pulley wheel to see rise and fall.
the piston rises and falls twice in one revolution of rota arm,so tdc line hits case seam twice in one revolution of rota,one for pot 1 and then pot 3.
put another way by some else on here with the valve covers off and rota arm pointing to pot/lead 1 you can easily turn both pushrods on cylinder 1 which denotes firing stroke on pot 1 then you can check your clearances of .006 thou on both valves then go through the sequence.

it baffled me for awhile til I realised the piston travels twice for one ignition.
hope this makes sense if not someone will say i'm stooped and put me right :lol:

I have an svda lecy points and pot 1 for me has the lead and rota arm lined up at 2 o'clock then 4o'clock for pot 4 then 8o'clock for pot 3 then 10 o'clock for pot 2.

 

[Bay-low71]

Here is the pic from 'How to rebuild your Volkswagen' by Tom Wilson

This shows the offset of dizzy shaft

Here's the setting valves piece

Hope this helps. Ben

 

[Johnny69]

I'm certain it's tdc on number 1. Number 1 valves have free play and number 2 exhaust is rocking in and out when the engine is turned.

Ill rewire the plugs soon and see if it starts.

............ :lol:

They must still run if the firing order is wrongly set? Well mine was anyway

 

[yachty]

I once had a dizzy installed 180 degrees out. It's not a problem as long as you wire up the ignition leads correctly.

Have you checked to see where no.1's ignition lead plugs into the dizzy cap? I suspect it will be in No.3's hole.

It's an easy fix anyway, with the engine at TDC on number 1, whip out the dizzy, take the spring off the dizzy drive dog, turn it 180 degrees and put the spring back on, then re-install the dizzy, put your plug leads in the correct order on the dizzy cap and static time and off you go.

 

[sparkywig]

I once had a dizzy installed 180 degrees out. It's not a problem as long as you wire up the ignition leads correctly.

Have you checked to see where no.1's ignition lead plugs into the dizzy cap? I suspect it will be in No.3's hole.

It's an easy fix anyway, with the engine at TDC on number 1, whip out the dizzy, take the spring off the dizzy drive dog, turn it 180 degrees and put the spring back on, then re-install the dizzy, put your plug leads in the correct order on the dizzy cap and static time and off you go.

Same here.

 

[Johnny69]

Hi yachty

At tdc it's pointing close to number 3 spark plug lead. Definitely not point got number 1.

I can't work out how it still runs like this to be honest - did yours still run when it was out like this?

Johnny

 

[yachty]

Yes, but is No3 spark plug lead going to no3 spark plug or no1 spark plug? Trace it from the cap and see where it goes?
I suspect it's going to no1 so although your dizzy is arse about face, the timing will be correct. Thats how mine was.

 

[maddog]

If its 180 out then you can swap two leads over on the cap

 

[Johnny69]

To summarise, at tdc on number one cylinder, my dizzy is pointing midway between number 3 and number 4 spark plug leads!

Looking at it tonight cos something's not right.

Johnny

 

[maddog]

If you turn engine 180 to BDC then look where rotor arm is pointing.....bet its at No,1

If so......swop leads over on cap.........1 & 3......try it and see if it fires.