11 replies to this topic

[DanJones96]

I'm struggling to get this engine started. Its an engine i've aquired as a spare, i know nothing about it and all ive done is change the headgasket and set the tappet clearence to 14thou. However after spending all yesterday messing about with my distributor trying to get a spark a new condenser and points gave me a spark. However my engine will still not start. There's plenty of fuel, i have spark and 140-160psi compression. As the engine's in the car how can i check if the timing is out?

[Daniel_moody25]

Take the dizzy cap off, rotate the engine to top dead centre on cylinder 1 and the rotor arm should be pointing at cylinder 1

[jaydee]

Still points and condenser so it easy to set static timing.

Crank the engine until the timing mark on the crank pulley is aligned to the TDC mark on the timing cover (this on Aplus engines, on a pre A plus you'll need to check it on the flywheel marks)

Connect a 12v bulb to the dizzy spade connector and a earth on the engine lump, the bulb will light while charging and the goes off at the point where  sparking

Twist the dizzy until the bulb is just turning off between the TDC and 6 degs mark

Job done

You can use a multimeter instead of the light bulb.

[TehMarchant]

First thing, have you got the leads on correctly? Cylinder 1 being closest to the thermostat and number 4 on the clutch side?

 

Have you got the leads then plugged into the dizzy firing 1-3-4-2 with in an anticlockwise direction? usually lead one is at about 1 or 2 o'clock on the dizzy

[Ethel]

Twist the dizzy clockwise and keep an eye out that the rotor arm still points at no1's plug lead.

[CityEPete]

Have you got a Haynes manual?

[DanJones96]

Sorry i should have said, engine timing.. Not if ignition timing.. I know how to set the distributor timing and that's correct the rotor arm is pointing at cyl 1 (closest to rad) at TDC and the HT leads are on 1-3-4-2 going anti clockwise from no. 1. I think the crank - cam timing may be out, how can i check while its in the car? I have a spare engine which im going to turn to TDC and see where the rockers are in relation to the engine that's in my car as i know the timing on that engine is correct. Is there any other methods?

[DanJones96]

Jaydee what is th 6deg mark? My crank pulley has a cutout and theres some teeth on the block, which of those teeth is TDC and which is 6 deg

[DanJones96]

^^ never mind i can see

[DanJones96]

Update: timing is defiantly out.. While on TDC mark cyl 2 is at BDC with the exhaust valve just starting to open.. When the inlet should be open, hopefully i can sort the timing out with the engine in the car

[CityEPete]

Lol, fork handles.

[dklawson]

Dan... try the following.

 

Most stock Mini cams have a symmetric profile meaning that the opening and closing profiles are the same.  This means that while we are used to talking about setting a cam by its #1 intake lobe center angle to a certain degree (such as 107 degrees) the cams can also be set "straight up".  You can use that fact to check the valve/cam timing.

 

I am posting a link below for checking straight up timing on a Triumph Spitfire.  It doesn't matter that you are dealing with a Mini and the A-series engine, The method is the same. 

 

Succinctly, when the cam lobe for valve 8 is at full lift, you adjust valve 1 to have an excess clearance of something over 1mm.  Likewise, when valve 7 is at full lift, you adjust valve 2 the same way to the same amount of clearance.  

Now turn the engine slowly in its normal direction of rotation until the clearance on valves 1 and 2 is equal.  The timing marks on the engine should now be lined up at TDC.  If the timing marks are not lined up, the cam is not set "correctly" for a stock cam.  A performance cam may deviate from this rule, particularly if its profile is not symmetric.

 

Anyway, this will give you an indication if the cam has slipped timing or was set up incorrectly.  If the cam is out by only a couple of degrees, that may be "normal" due to timing chain stretch.

 

If you do find the timing is out enough to justify fixing it, you can do this in the car but it is a fair amount of work.  You will need to remove the radiator and some of the work has to be carried out with long socket extensions through the opening in the inner wing.

 

http://www.mgf.ultim...iming/index.htm