Recently Rudy and myself purchased a pair of Apollo AV-1 Diver Propulsion Vehicles. (DPV) or underwater scooters.
The units are approximately 10 years old, (at May 2013) and are very good condition. The first thing I did was check out the batteries and the O rings. The batteries tested fine under a 8 amp load for 60 minutes. The Battery/Case O rings need replacing.
The Black O ring is a standard off the shelf O ring part number BS 271 9 1/4" Inside Diameter and a 1/8" cross section. Cost $5.28 each. Apollo want $36 each for them.
The Red O ring, I contacted Apollo Australia and was quoted $99.67 plus GST, and they told me to contact St George Underwater Centre, who quoted me $80 for the Red one and $50 for the Black one.
Apollo USA has a price list dated August 2012 quoting $36 for each of the O rings. A big difference. Postage from USA can be as little as $20. I eventually found a supplier in the USA who would supply them, but wanted a $75 fee for international shipping for an order less than $250, plus $30 shipping. so 2 x $36, + $30 + $75 = $177.
On the 8th page of a Google search I found a site and contacted them. They are in Delaware USA and can supply the O rings for $29.95 each with postage of $9.95. A great deal compared to all the others. He asked for my phone number and I spent about 30 mins talking to him about the Apollo's. He has a fleet of 10 units and hires them out for $75 per day. They use them for fossil hunting.
He explained to me what parts breakdown a lot and how to make some simple modifications to help when parts break. Red O Rings are US$29.95, Springs are US$3.95 each and Switches are US$6.95 each. He has all the parts for any repairs required.
All the manuals and diagrams for the AV-1
Repair Manual Front Cover
Repair Manual Motor Bulkhead
Repair Manual Propeller