MFI thermostat mounting on a 69's 911E

[SFE]

I'm wondering if on an early 69's injection pump (0408 126 002) this gasket should be present (red arrow) ?



My car seems to run too rich at idle...

Thanks !

[2.5MFI]

That's not a gasket, that is a metal spacer/shim. There are several different thicknesses. 1.35mm for the early pumps and then I believe 2.10mm for the later pumps. Sizes come in 1.35mm; 1.50mm; 1.65mm; and 2.10mm. There might be a few other sizes in-between what I posted.

[SFE]

That's not a gasket, that is a metal spacer/shim. There are two different thicknesses. 3mm for the early pumps and then I believe 4 or 5mm for the later pumps.

I've seen some cars without this spacer.

My car runs rich with this spacer and run perfect without.....is there a problem to remove it definitely ?

[2.5MFI]

No problem if your engine likes it. If you ever want to put the spacer back on just add a shim that's the same thickness into the thermostats shim stack.

[SFE]

No problem if your engine likes it. If you ever want to put the spacer back on just add a shim that's the same thickness into the thermostats shim stack.

Thank you for your answer !

So if I don’t put the spacer back on I can remove a shim into the thermostat stack in order to be a little bit more rich during cold start ?

[2.5MFI]

Yes removing one of the round shims will richen up the cold start function of the thermostat. Normally you will find several different shim thicknesses. From 0.15mm to 2.10mm. In my parts box right now I have these sizes: 0.15mm; 0.25mm; 0.35mm; 0.80mm and the 2.10mm shim. If your shims (normally 4 to 6 shims) consists of a 0.35mm shim I would start there.

This is the corrected size list. Not enough coffee this morning.

[SFE]

Yes removing one of the round shims will richen up the cold start function of the thermostat. Normally you will find several different shim thicknesses. From 0.15mm to 2.10mm. In my parts box right now I have these sizes: 0.15mm; 0.25mm; 0.35mm; 0.80mm and the 2.10mm shim. If your shims (normally 4 to 6 shims) consists of a 0.35mm shim I would start there.

This is the corrected size list. Not enough coffee this morning.

It is Cognac Time for me (end of my diner !!!).
And I guess the number of thermal disk pair should be 25 ?

[2.5MFI]

Yes 25 pairs of the thermo discs.

[SFE]

I am affraid I still have a question…

If I remove one shim I will richen up the cold start fonction.
But the risk is that the rod won’t go anymore inward enough to the lean position when the engine will be warm ?

Thanks !

[2.5MFI]

The rod will have no problem extending in all the way. The 25 pair of thermo disc's will do the job even if you remove a few more shims.