cold start lever position on 1.6 TD IP for setting timing?

[87octane]

When timing a 1.6 TD IP, the book says move the cold start lever somewhere.
With the engine and IP bolted together on a stand, should the cold start lever be shoved forward towards the pulley or backwards towards the flywheel to set the timing?

[rabbitman]

Towards the pulley.

[87octane]

Awesome. Thanks.

Next question, I've read both SAE papers and Bentley and I still don't understand what the cold start circuit does beyond "enrich when engaged". Is there a resource that goes deep into the IP and explains how each function does what it does and why?

I've got a Mitsu TD and I can't figure out WTF the cold start circuit ain't doing, cuz it ain't getting the truck to start in the cold, that's for sure.

[Vincent Waldon]

Assuming we're talking about Bosch VE pumps here, the cold start lever mechanically advances ignition timing about 5 degrees (crank)...up to about 2000ish RPM, at which point the pump's internal dynamic timing advance takes over.

Advancing the timing slightly makes the engine easier to start when cold.

On some cars so equipped, the cold start lever is also mechanically connected to a pump lever that also ups the idle slightly, to improve drivability when cold.

[87octane]

Vince, does this mean that while setting the IP timing, the cold start circuit is NOT engaged (timing is normal)?
My Zuki cold start cable is an add on that flops around on the floor between the seats and I can't reference it's behavior to any more sanitary vw factory dashboard cuz I haven't seen a vw factory dash yet. It's very hard to find any vw IDI diesels in the junkyards in the Bay Area.
So: cold start cable knobbed pulled out of dashboard is "engaged, timing advanced, IP lever towards flywheel, must be cold)
And: cold start cable knob pushed all the way in is "not engaged, timing normal, IP lever towards pulley, must be warm) ?

[Vincent Waldon]

Yup, you got it.

To put it another way... when setting the static timing it's important that the cold start feature be disabled.

Disabled means:

- cold start handle pushed all the way IN to the dash, on cars so equipped

or

- cold start lever on the pump all the way towards the pump sprocket

[87octane]

Now we all know what I'll be doing tonight....

[ToddA1]

On some cars so equipped, the cold start lever is also mechanically connected to a pump lever that also ups the idle slightly, to improve drivability when cold.

Interesting.... I need this.  Is it a simple added arm?

My motor wants to jump out of the engine bay when cold.  I have to hold the throttle to smooth it out.

-Todd

[Wayland]

Pumps from I think 86 on came equipped with this feature.

[vanbcguy]

On some cars so equipped, the cold start lever is also mechanically connected to a pump lever that also ups the idle slightly, to improve drivability when cold.

Interesting.... I need this.  Is it a simple added arm?

My motor wants to jump out of the engine bay when cold.  I have to hold the throttle to smooth it out.

Nope, there's a bunch of stuff inside the pump that's not there in the older ones.  Easiest way is just to find a newer pump - the 109 style pumps have the fast idle, the 107's don't.

[ToddA1]

Safe to say 109s are from '86 on? 

My car is a 82, btw.  I never specified, but you seem to know what I have.

-Todd

[burn_your_money]

Yeah about 86 and on got the fast idle. It *could* be added to a pump but you'd basically have to buy a donor pump that has it, at which point you may as well just use that. You will also need to calibrate/adjust the pump afterwards.

Many vehicles *retard* the timing for cold starts. I don't think that that's possible on a VE pump though.