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Crash Bar Oil Cooler

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The function of an oil cooler is to obviously cool oil. However there are factors involved that make the previous statement a little more complex. A TC88 uses engine oil for lubrication as well as for internal cooling of the lower cylinders and piston bottoms. In this modern age of internal combustion engines maintaining proper heat ranges of engine parts leads to longer life, lower emissions and better mileage. When oil temps rise above 230df the detergents and additives begin to deteriorate and loose effectiveness. As the temperature increases the longevity of these additives decreases. At about 300df the additives are all but oxidized and the oil has little lubrication qualities left in comparison to the lubrication available at 200df. By 400df petroleum oils are oxidizing, thickening, and volatiles are boiling off causing part of what is known as "oil consumption". This causes the volume of oil to decline and heat to rise even more. This makes the problem of excess heat carried by the oil even greater. Add to this the oil is now coating and baking on to most of the internal engine parts creating the first layers of varnish and sludge. Piston rings begin to collect the super heated oil and carbon forms from the oxidized oil leaving rings to freeze and loose their sealing properties.

If oil is kept too cool it can have detrimental effects as well. Oil below 212df will not boil off acids that form during combustion and condensation. Oil below 212df will vaporize acids more slowly than boiling however the process becomes slower as temperature drops. Below 150df oil has not thinned properly to provide for optimum lubrication and has a slow acid vaporization. Oil below 50df may not be thin enough to provide adequate flow through passages or may even promote moisture or condensation depending on ambient weather conditions.

Synthetic and multiviscosity oils give the greatest range of proper lubrication. Synthetics add almost 100df to the range of oil usability compared to petroleum plus are pourable to below -50df.

The following is a photo essay of a quick and inexpensive oil cooler installation. There are other types available and each has its own efficiency ratings. That subject is for another chapter in "Oil Cooler".

Engine Guard Oil Cooler

Remove and measure for inlet/outlet hole plus drain.

Drill 11/32" holes for 1/8" pipe tap.

Tap holes with 1/8" pipe tap using caution and being conscious of depth.

Clean ALL METAL fragments and chips from inside of engine guard. Use a bore light to illuminate interior of tube. Rinse with solvent to double clean any debris that may be present.

Install oil cooler base making sure all surfaces are clean.

Install fittings and drain plug as needed in engine guard.

Finish attaching hoses and routing oil lines.

Install oil filter and fill with oil. Start engine and check for leaks.

Ride on. The oil cooler is almost hidden and can barely be noticed without close inspection. The engine guard is now the oil cooler. There is no worries about rock damage on the highway plus in this case the bike now carries 1.5qt. more oil. Total oil is 4.75qt with filter.

The thermostat used is a Lockhart DP-180. It starts to flow oil to the cooler at 160df and is full open at 180df. While riding the highway under fully loaded conditions the oil maintains at 175df with almost no variation. The engine guard is warm on the supply side and cool on the return side. The guard can be hand held easily. The extra 1.5 qt of oil acts as a heat sink with the thermostat allowing the mixing of cool oil into the engine hot oil in a balance to maintain the 175df temperature. This mixing of hot and cool oil offers the benefit of almost no oil oxidization due to engine heat. This alone will increase the beneficial additives of the oil through the entire life cycle of oil from change to change. Add to this the TC88 will be cooling the underside of the pistons with a constant 175df oil stream. This has the capability of providing a stable piston temperature that can help promote controlled consistent combustion plus help eliminate the piston as a source of preignition. It will also help prevent the piston rings from accumulating carbon deposits from overheated/charred oil. This will help keep rings from sticking and provide a better film strength of oil between piston, rings and cylinder walls. Other benefits can be derived from cylinder head cooling with a constant oil temperature. This can also extend the life of the one way head breather valves by an indeterminate amount.
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wow i thought i was the only one doing this been using my crash bars for cooler sence the 80.s here in the high deasert it works great !
in the winter they also work well as a hand warmer!
can i route the oil line from the engine to the crash bar inlet to then from the crash bar outlet to an h-d oil cooler inlet and out the outlet back to the engine
Anyone answer this question? I want to do the same thing but wasn't sure about the oil in the crash bar backing up into the oil tank. Over a quart of oil could be a real problem I would think!
I read the post that Mr. Data posted and installed one on my 2004 Fatboy. The temperature when cruising is lower but not so much in town. I recently completed the first oil change since and I pulled of the noses at the ends and blew air through to clear. I bled the crash bar when I refilled. Wasn't too bad ,but more than ordinary.
has anyone did an engine guard oil cooler on tc 96, 08 or later touring bike if so would sure like to see some pics:small3d012:
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