Oil Field Engine News

Setting Up Oil Field Engines


| August/September 2002



Oil Field Engine

We are happy to have received another submission from Charles Gray in the form of a continuation of an article he wrote last year. In the July 2001 issue of Gas Engine Magazine, we presented Charles' article, Setting Up Your Oil Field Engine. The article, intended for the novice oil field engine owner, offered suggestions for gas and air settings that would make starting as effortless as possible. It also included some information that would be of interest to any oil field engine owner. Feedback from readers was positive, making us feel the effort to provide this information was worthwhile.

Two responses came from novice owners starting their engines for the first time, and both of them stated they never thought starting their engines could be so easy. We also heard from a fellow who re-plumbed his hard-starting engine after reading that article, expressing his surprise at how easily it now starts. This follow; -up article answers a few questions that arose from Charles' first article, and it also includes additional tips.

Air and Fuel Intake

The original article suggested that a gate valve be placed on the air inlet to the engine to significantly reduce the inlet air and provide a precise adjustment. Typical oil field engines have a pipe-threaded 1-1/2-inch or 2-inch pipe at this location. If your engine does not have a pipe thread you will have to improvise. Gate valves can be purchased new at any plumbing supply house, or used at flea markets and the like. You can also use pipe reducing bushings and a smaller valve, if need be. The original article suggested an initial opening of 1/8-inch as a starting point. We now feel that a 1/16-inch opening is a better starting point.

The article also suggested that a valve with a diamond-shaped opening or a needle valve be used to control gas flow. Gas valves with a rectangular-shaped opening do not provide the precise adjustment required, making starting difficult. Needle valves allow better adjustment than diamond-shaped valves, and while the diamond-shaped valves give a better appearance to the engine than needle valves they are hard to find.

Small needle valves with 1/4-inch or 3/8-inch pipe threads provide the best adjustment. A rectangular gas valve can be used for the sake of appearance, with a small needle valve discreetly located upstream for actual fuel control. Needle valves can often be found at flea markets, and they can be purchased new from various supply houses or one of the numerous suppliers advertising here in GEM. They are available with the inlet and outlet in line with each other or at a 90 degree offset.

Propane Tanks and OPDs

Any time your propane tanks are disconnected from your engine you should make sure the safety plugs are reinstalled on the gas outlet of the tanks. You should also install caps on the ends on the propane hoses and cover the gas inlet on the engine. These caps can be plastic plugs, metal caps or plain aluminum foil. The smell of residual propane seems to attract spiders, and the spiders build nests that block the flow of gas, making it difficult if not impossible to start an engine later on.