Done A Silly Thing

[tvr5000]

With a lapse in concentration I've taken out the distributor to attach the vaccum as it had come loose and forgot to mark up where the rotor arm was, so now its all to cock.
Does anyone know of the simplest way to reset the timing.
97 5ltr chim.
Cheers
Numpty!!

[sparkypete]

Well not sure if there is a difference, but for a rover V8 4.0ltr the procedure is to get No1 cylinder to top dead centre, this means removing the spark plug from the front passenger side cylinder and gently placing a long implement into the bore, you them turn the crankshaft pulley round with you hand until the piston pushes the implement up to its maximum height just before it starts to go back down again, you them insert the distributor with the rotor arm pointing to the position of the sparkplug lead which runs to the No1 cylinder, please note that the rotor arm will need to be positioned approx 10mm from the desired point as the arm will rotate slightly as the screw engages the drive as the distributor is lowered.
This should get the car running and then allow you to fine tune with a timing gun.

Hope the abve helps.

Pete

[tvr5000]

Cheers Pete. I'll give that a shot today.
Mick

[Hut49]

The method mentioned could give you a 180 deg error (i.e. at the end of the exhaust stroke rather than at the end of the compression stroke). Either (i) put your finger over the plug hole while turning the engine over - pressure against your finger will indicate that this is the firing stroke, so then look at the front pulley and turn it to tdc according to the marks on the pulley; or (ii) remove the oil filler cap and watch cylinder No.1 exhaust rocker moving. When this happens (i.e. the exhaust stroke is occuring) note the TDC marks on the front pulley - you are 180 degrees out at this stage - so make another full turn of the crank (noting the build up of pressure in cylinder No.1) and that will be the correct TDC.

[tvr5000]

Hut49 said:

The method mentioned could give you a 180 deg error (i.e. at the end of the exhaust stroke rather than at the end of the compression stroke). Either (i) put your finger over the plug hole while turning the engine over - pressure against your finger will indicate that this is the firing stroke, so then look at the front pulley and turn it to tdc according to the marks on the pulley; or (ii) remove the oil filler cap and watch cylinder No.1 exhaust rocker moving. When this happens (i.e. the exhaust stroke is occuring) note the TDC marks on the front pulley - you are 180 degrees out at this stage - so make another full turn of the crank (noting the build up of pressure in cylinder No.1) and that will be the correct TDC.

Thanks again.

[GreenV8S]

Hut49 said:

so make another full turn of the crank (noting the build up of pressure in cylinder No.1) and that will be the correct TDC.

Given that you have already disturbed the dizzy and hence lost the timing, if you have determined that it's 180 out, it is easier just to lift the dizzy and turn the rotor by 180 degrees before you put it back.

[Hut49]

GreenV8S said:

Hut49 said:

so make another full turn of the crank (noting the build up of pressure in cylinder No.1) and that will be the correct TDC.

Given that you have already disturbed the dizzy and hence lost the timing, if you have determined that it's 180 out, it is easier just to lift the dizzy and turn the rotor by 180 degrees before you put it back.

Your right, of course, but I thought it would be helpful coaching to have the unexpurgated version that would help with understanding the mechanics rather than just offer the short cut.