Unable to set timing to spec

[mblake4u]

I'm unable to set my timing to spec (5 BTDC with the vacuum hose disconnected at around 900 RPM) on my 1.9l T25.

I recently got the van back from the garage and they'd set it very advanced, and it seemed to run OK, but I know it's supposed to be 5 degrees BTDC, so I tried to set it to that. The closest I can get it to that is about 15 degrees BTDC. I've got a pulley with a dimple-shaped notch at TDC and then 5 degrees to the right the 5 BTDC v-shaped notch.

Judging from these two notches, I estimate that I'm getting the spark at about 15 degrees BTDC, i.e. when the timing light flashes, the 5 degree notch is about 10 degrees to the left of the join in the crankcase.

Now I know this is wrong, but it doesn't sound like my engine is knocking. When I adjust the distributor to get closer to 5 degrees the engine cuts out - say 10-12 degrees and it's out.

Has anybody had this problem and know what to do?

[Aidan]

are you blocking off the disconnected vacuum hose to the carb ? Is the other vacuum hose to the air preheater nonsense connected and connections intact or blocked off ?
What altitude are you at ?

[mblake4u]

Hi,

The preheater one is blocked off, the vacuum one too and I'm at sea level..

Cheers, Michael

[ninja.turtle007]

Might sound silly but us the distributor cap in the correct position?

[bigherb]

Which engine have you got? 1.9 suggest a flat four water cooled or is it air cooled or the straight four water cooled?
Has it got an idling stabiliser unit. If it has you need to disconnect the plugs and join them together before adjusting the timing.

[mblake4u]

Hi,

thanks for the replies. It's the 1.9 flat four watercooled. I've wiggled the distributor cap and you can probably move it the equivalent of about 3-4 degrees but it's definitely on the correct way. This model doesn't have the idling stabilising unit.

In case anyone asks, the degrees on the timing light is set to zero and it's connected to the lead to cylinder 1.

Regards, Michael

[toomanytoys]

Back to basics first..
Does the rotor arm line up with the notch in the dizzy body when the tdc mark is at the case split???
Could be the dizzy drive has been put in 1 tooth out...

Can you take a pic of the engine bay also... ?

[mblake4u]

Thanks for the reply.

If you have a look at the one picture closely you can see the notch in the dizzy body. At TDC, the rotor is 90 degrees from the notch, but it is still pointing to cylinder one's lead. The reason the dizzy is rotated 90 degrees is to stop the vacuum advance pushing into the water pipe.

Having the dizzy rotated 90 degrees shouldn't make a difference as far as I can tell - unless I'm missing something.

I know I've got the wrong rotor in - I took the rev limiting one out as the one they put in when it came back from the workshop was quite old and tatty so I wanted to eliminate that as a cause (I've got a tachymeter fitted so I watch the revs when I drive).

The dizzy drive could still be out by 1 tooth couldn't it? How many degrees would that be - I guess 360 divided by the number of teeth?

Having a look at the Haynes manual, it's got a diagram with the rotor pointing to the notch in the dizzy (and both of them pointing at the split in the case/TDC mark). If that's correct then my dizzy drive must be out by 90 degrees (give or take a tooth)!

Thanks for the help - I hope I can get this sorted..

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[Aidan]

so it's pointing to number one just the case of the disi is out by 90 degrees so rotate the disi back to the right place and move the leads round the cap by one and it'll be right advance unit doesn't foul anything much normally it sits in the space above the clamp stud; timing notch number one normally points toward rear stud of fuel pump/lifting lug/case timing split

[mblake4u]

Hi Aidan,

Thanks for the reply - I managed to get the timing to spec. I got the engine really hot (to the point of the fan coming on) and then was able to get it 5 BTDC, rev counter bouncing about a bit at 5 BTDC, but it doesn't die.

So I thought, will it still start from cold? It's been a few days and it seems to be running OK. Bit rough when cold and smoother when warmed up.

Thanks to everyone who replied.

Regards,
Michael