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Retard side of my dizzy's vacuum advance/retard can is leaking...any ideas on where to find another can? I've checked the usual parts suspects, no joy. I'd bet it's bad gri gri to run a D-Jet 412 with the retard side leaking, right Ray?

Try Kerr automotive in Oklahoma city...405 232 9581. Not all of the 411/412's with injection came with a dual vacuum advance. The single unit is still available last I heard. I bought one at Kerr several years ago. If you deceleration valve is working well...it should be no problem to do without the retard. Ray

Thanks for the vendor reference, Ray!

Actually, my 412 does not have a decel valve, and there's no evidence of one having been installed ever, either the pneumatic type or the electric type. Did all 412's have a decel valve from the factory?

The advance side of the can is leaktight, so can I use it and not connect up the retard side?

Yes, you can. It was "mainly"...an emissions device, but didhave some peculiar benefits to the fuel injection. On the models with teh cut-off switch in the TPS...its was nice to have eiuther the decel valve..or ignition retard....due to the fact that on high speed over-run...you could have mometary lean spots and be running high advance rates. Tes, supposedly it should be fine with no fuel at all at these poinst (total cut-off) versus...lean and pinging....but what would happen on some cars is that the sensitivity of the whisker switch can cause it to jump on and off (the shut-off switch) due to its sensitivity. It would cause lean burn instead of no-burn.
Look on the black arm that holds the MPS. Are there two open srew hles in the top...about 19mm apart? That is where the manual decel valve went. You should also have the funky vacuum Tee that went between the aux air reg and the plenum...as well as a spare nipple on the left side of the manifold near wher the MPS hose comes from. Or...on some L-jet models, they used the electric.

It should be fine without either retard or decel....but if you start seeing the idle creep up....check the long loop on the skinny spring in the mechanical advance...and tighten it with a pair of pliers. Ray

That's why I always ask with my D-Jet engine, sometimes those "emission" devices serve a second purpose...thanks again for the good info Ray. And, there are no extra holes on the MPS bracket, so I guess my 412 didn't have a decel valve.

hi , mg , he have couple place who sale that , exap. bus dépot , or bus boy , or cip1 , the price for that is appx. 50-70$ restore or new , and for your decel valve he have that , for mt, trs. vaccum decel valve , if you want to instal new ,i do reserche in my internet page ,,,albert