MaineSail pointed me towards Rydlyme a while back. Oddly, it is really hard to find it in the PNW. My nearest dealer is selling it out of the Bremerton Yacht Club as a side business. It would also require an external pump to circulate it through the system. I was hoping for a somewhat simpler process using cheap house hold products and utilizing the impeller to drive the product through the engine. Oh well, thanks for the info, much appreciated.
You really dont need a fancy recirculation technique to do this with a small marine engine.
Put it in a bucket.
Disconnect the hose from your inlet through-hull and add (using a straight hose barb connector) enough extra hose to reach to the 'bucket'.
Disconnect the hose that feeds your water injection elbow and add (using a straight hose barb connector) enough extra hose to reach to the 'bucket'.
Suck up the contents of the bucket until the recirculation discharge (from the extended hose from the injection hose) begins to flow.
Shut down and wait 15 min. or so; then, run engine 'briefly' (15 seconds or so) to recirculate; etc.
Usually an hour 'soak', will be sufficient unless your engine is 'really' fouled.
In a pinch you can simply ignore recirculation, just suck up the chemicals into your raw water pump until 'gone', then after a time (30 min or so) just 'push' the slug of chemicals through to the next section by reconnecting the pump inlet hose to its throughhull, etc. .... ..... when the water from the exhaust outlet begins to turn brown, youre done; so turn on the engine to stop the chemical reaction and flush the engine with raw water, etc.
Note: When finished recirculating, pour the residual from the bucket down your head (but not enough to come in contact with the porcelain bowl), let soak - to clean off all the calcium deposits from the head's check valve, joker valve ... and the 'overboard' hose which usually becomes totally blocked by calcium deposits over time when flushing with seawater.
Other: CLR and other 'household' chemicals are usually mixtures of hydrochloric, etc. acids, are not 'inhibited'
and vs. cast iron will rapidly begin to 'attack' an engine's internal metal components.
Other: After you 'descale' an engine, you 'should' then 'heat soak' the engine for several HOURS by running at near full open 'throttle' and under near full load to re-form the protective 'black' rust (ferrous oxide). This applies with the usage of raw non-inhibited acids such as muriatic, hydrochloric AND 'inhibited' boiler descalers, etc.