Pioneer DVL -909 skipping back problem

Before you dig into the adjustments, make sure the sled moves easily on its tracks - the grease isn't gummed up, etc.

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Agree with Sam. Sounds like a problem of mechanical sticking to me. What happens is that the optical block doesn't move on every few seconds as it should, so the lens continues to bend to follow the track, until it reaches the limit of its movement, whereupon the tracking servo loses lock, and the lens flies back to its 'neutral' position. Servo lock is re-established, and play starts again from this position. The extra 'grunt' that's applied to the motor when in search mode, easily overcomes the stickiness. Try cleaning off the slides and relubing them with floil if available, or a light synthetic machine oil if not. Also, rotate the drive gears manually, and feel for any 'bumps', to check that there is not any foreign particle lodged in any gear teeth, or that the pinion gear on the motor shaft, has not split betwen two teeth. Electronically and adjustment-wise, these Pioneer laser disc players have been pretty reliable.

Arfa

I've seen a broken grey plastic bracket which holds the gears in place which moves the pickup. The bracket attaches to the pickup itself, and the posts inside which hold the gears in proper position fail. Can't be seen til the bracket is removed. Seen it enough times I keep the part in stock. Don't remember the part number though, and I'm not positive this pertains to your model.

Mark Z.

Thanks to all the replies I got it fixed I played through a LD and it skipped every 4 minutes on either side of any disk so it had to be the gears off the motor Upon disassembly I found the first gear off the motor had a burr on it about the size of a grain of sand where it connected to the second gear . Appeared to be a manufacturing issue I cleaned it up with an X-acto knife and all is good For a machine that cost well over $1000 new I'm glad I bought mine used as this is the second problem I've run into thanks again Bob

Glad you got it sorted. The 'grain of sand' in the gears is not at all uncommon with players from any manufacturer, which is why I mentioned it in my first reply. I don't know whether it is maybe a plastic grain from the original moulding process, that sticks to the gear, and eventually 'breaks free' and finds its way into the gear teeth. Obviously, it can't have been there in the teeth from new, otherwise the player would have had a problem from new, but sometimes, these little grains can be so hard to get out from between the teeth, that you would swear that they must have been moulded in.

I guess that you have probably lubed it all up now, but in answer to your earlier question, the original lubricant used in most players is floil. this is a sort of synthetic oily grease. It's usually white, thicker than oil, but lighter than grease. A very acceptable alternative, that I have used for years, is an aerosol product from Electrolube called "CMO" (clear mechanical oil). It is a light synthetic machine oil, which is completely non reactive with plastic and has a really good 'cling factor' when applied to shiny plastic and chrome plated parts, which is of course important for lubing precision components like the slides of a CD/DVD pickup.

Arfa