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FlowKooler Water pump

Flowkooler waterpump
Texas in the summer.  Such a mild climate.  Perfect for wheelin’ in the scorching heat with little to no air passing through the radiator. Note the sarcasm, because we’re laying it on pretty thick.  One of the key areas that we need to address on Project Over Easy is the effectiveness of the cooling system. 

FlowKooler advantage:

FlowKooler high flow water pumps push twice as much coolant through your cooling system at low speeds than stock water pumps and help the engine transfer the heat, resulting in engine temperature reductions of up to thirty degrees.  Higher flow volume also increases cooling system pressure within the engine block resulting in reduced instances of detonation as well as improved flow efficiency.  Plus, water under pressure has a higher boiling point too for greater cooling efficiency. 
Since 1995, FlowKooler has focused on increasing cooling system flow rates at lower engine speeds to resolve low speed overheating.  Face it, cooling systems cool a vehicles engine by having air pass through a radiator. FlowKooler addresses this problem by making water pumps that deliver double the volume of stock pumps at engine speeds below 3,500 RPM and typically outflow “performance” pumps by 20%.  At 3,500 RPM and higher the gallons-per-minute flow rates level off to standard flow rates.

Flowkooler waterpump and robertshaw thermostatWaterpump and Thermostat selection:

We began our cooling overhaul by going straight to the heart of the matter, the water pump and thermostat.  FlowKooler was contacted for guidance on component selection including a water pump and thermostat that would best match the Scrambler project vehicle.  They recommended a high flow FlowKooler water pump in cast iron (part# 1774) and a 180 degree Robertshaw thermostat (part# 330-180). 

The Robertshaw Thermostat:

FlowKooler recommends and sells Robertshaw thermostats (shown at right vs. the stock GM thermostat shown at left).  Consider the Robertshaw company as the grandfather of thermostats – they made some of the first thermostats back in 1916  for some of the first American cars. In other words, they know their stuff. 
Today, Robertshaw thermostats are still leading the industry with key features like a balanced pressure feature that allows equal water pressure on both sides of the thermostat even before the thermostat has fully opened.  This enables the thermostat to respond to temperature only, better controlling engine and cooling system temperatures. 

Installation - Flowkooler Waterpump and Robertshaw Thermostat
Time: 8-11 hours 
Tools Needed: Wrenches, sockets, ratchet, screwdrivers, gasket scraper, catch-pan, wire brush for drill, paper-towels / rags.



Flowkooler waterpumpFlowkooler waterpumpRemoving the old water pump and thermostat – The Small Block Chevy engine installed in the Project Over Easy Scrambler provides a straight-forward platform for the water pump and thermostat swap.  For the purposes of this installation, and to ease the documentation of the install, we performed the water pump and thermostat update with the radiator and radiator support removed from the vehicle. 

Typical installations will only require the removal of the fan belts, engine fan (if so equipped), water pump pulley and the actual water pump.

Flowkooler waterpumpFlowkooler waterpumpThermostat replacement requires only the removal of the thermostat housing.  As with each of the other updates made on this project vehicle, we allowed plenty of time for the WD-40 to penetrate the water pump and thermostat housing bolts.

With the stock water pump removed, it is time to thoroughly cleaned the gasket surfaces and prep for installation of the new FlowKooler hi flow water pump.
Water pump and thermostat installation – This is one of those projects where installation is truly the reverse of the water pump and thermostat removal.  The only additional step required for our installation was the swapping of a heater hose outlet from the stock pump to the FlowKooler water pump. 
Flowkooler waterpumpWith this step complete, it was a simple installation for the FlowKooler pump and all related components (pulley, fan, fan belts) as well as the new Robertshaw thermostat. 
Once installation / reassembly was complete it was time to add the proper ratio of water/coolant and then fire-up the engine to check for leaks and cooling results.



The Verdict

The FlowKooler water pump and matched 180 degree Robertshaw thermostat are clearly high quality components designed for severe usage including low speed off-roading in high temperature climates.  While the Project Over Easy Scrambler does not have a temperature gauge with incremented degrees (we’re still running the stock Hot/Cold temperature gauge) there was a clear decrease in the level of the temperature needle.  This benefit is even greater when you consider that the completion of this product test was in the middle of the hot Texas summer. 
These components fit without any modifications.  The provided instructions were simple and clear.  The resulting performance was improved from stock.  With all of these results so positive, it is apparent that FlowKooler provides quality cooling components.  We look forward to putting our cooling update to the test later in the year with a 4X4REVIEW wheelin’ weekend.


500 Linne Road – Unit I
Paso Robles, CA 93446
Phone: 805-239-2501 
Web: www.flowkoolerwaterpumps.com

About Rick Webster

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