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Escortmk1
25-04-2004, 23:03
Ive just fitted a new xflow engine in my mk2 van and got it running.

i have fitted a new Aldon 43D4 103FXYS Distributor with a new lumenition kit, ive set the static timing etc.

When the engine is running the rpm rises and falls a couple of hundred revs, i have rotated the distributor a couple of degrees each way but the fault stays.

Also the mechanical advance seems faulty, when you rev the engine and take your foot off the accelerator pedal the revs dont drop instantly like they should.

There are no noticable air leaks on the inlet side.

I can't get the engine to idle properly is the distributor at fault or the carb ?

Any idea's ?

Andy

Clint
25-04-2004, 23:16
I would check the two halves of the dizzy are fittd properl, soulds like th top half may be free to do what it wants almost

Escortmk1
26-04-2004, 18:15
Clint,
Everything is tight on the Aldon dizzy, its a new one so im reluctant to pull it to pieces.
However i previously fitted the standard dizzy with vacuum advance and the revs drop as they should when you take your foot off the accelerator but the idle is not stable, this is why im thinking it might be down to the carb.
I think i should swap the carb and dizzy and see if the problem still occurs.

Andy

Miniliteman
26-04-2004, 19:32
The FXY(S) dizzy is for a Xflow with twin carbs and a hot cam; do you have those? Sounds to me as the Aldon unit gives too much advance at low rpm, seen this before. Normally the vacuum would dissappear to the dizzy when you release the throttle which would bring down the advance which in turn would bring the rpm down in an instant. With the FXYS-unit the advance stays higher, it has no vacuum unit and has a higher advance build into it to compensate for the twin carbs and a hot cam.
Hope this all makes sense.

Leon.

Escortmk1
27-04-2004, 18:08
Miniliteman,
Yes i do understand, The xflow spec is all new and unrun, 1600cc +90 thou pistons, lightend and balanced bottom end including flywheel, clutch front pulley etc, stage 2 head with larger valves, double valve springs, piper 285 cam,
i just thought i would try the Aldon dizzy as it was new and it came with the engine.
I did however use a piper vacuumless dizzy on my last xflow and it worked fine.
I have a new std 1600 xflow dizzy on its way which i got off ebay, hopefully with the 32/36 dgav carb which im in the process of cleaning and rebuilding with a new service kit and the new std dizzy the engine will settle and i will be able to set it up better.

Andy

x-pack
20-12-2009, 22:27
Any joy with this one? Mine is doing the same thing now!