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Simple question for a simple mind

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jbowlby

jbowlby

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I need to replace the vacuum advance unit on my Midget. Im kind of leary on pulling the distributer for fear of messing up the timing.

Is it as easy as marking the location and noting the rotor position to the drive?


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https://www.carsandcyclesagainstcancer.com/
 
Really simple, pull cap off, rotate engine until it points to #1 for reference.

Undo two bolts, not the pinch bolt, holding distributor plate to engine

Give it a little tug and it pops right out.

Reassembly reverse of above. It is a slotted drive and even if you mess up you are 180 degrees off.

Just as long as you don't loosen the pinch bolt it's really, really simple.
 
You need to mark a reference as to where the distributor housing is before you remove the unit. The rotor will drop back into place because of the slot in the drive gear, but the housing can turn and that will alter the timing. Get it as close as possible and it should be fine. Rechecking the timing after you're done would be a good idea though. I know that's a pain on an A series with the timing marks underneath. That can be taken care of with one of the timing tape and pointer kits from Advanced Distributors. https://advanceddistributors.mybisi.com/product/84779/1275-Midget-Sprite-Timing-Tape-Kit_404923.html
Makes timing a A series an easy job.
If the vacuum unit doesn't take care of your problems then Jeff at Advanced Distributors is the guy to see. Highly recommended!
 
I don't know about 1500s, but on the A series....


A reference mark is a real help, and if you do it by removing the clamp instead of the pinch bolts the timing will be as it was. However, I find it easier to loosen the pinch bolt than to gain the access to the clamping plate. As long as you aren't pulling the "shaft and action plate" assembly out of the dizzy, there is no chance of being 180 degrees out, as the drive dog is "handed".

definitely worthwhile to have the timing marks moved so you can see them from above, whether with the kit, or some other method!..

The book says (just in case you HAVE completely disassembled the dizzy (getting the springs back on can be a real pain in the ass, but it is do-able) ---When engaging the cam driving pins with the centrifugal weights, make sure that they are in the original position. When seen from above, the small offset of the driving dog must be on the right and the driving slot for the rotor arm must be in the six o'clock position.
 
Thanks everyone! I did buy one of the timing relocation kits but haven't installed it because I need to pull the Radiator ect....

Anyone have a good source for the vacuum advance module? 69.00 from Moss (ouch) and I didnt see one in the VB catalog.
 
Jeff should have a source, probably at a better price.
 
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