blown motor

[ghetdjc320]

14 hours ago, 75sv1 said:

I do have the triple fans on my 2000 XJ. I do not note any overheating. I used the Dirt Bound fan frame and SPAL 10 inch fans. I do mainly open road, some intown. I think it cools a bit better while driving. I do have my concerns if I was to be in heavy stop and Go traffic. Also, if wheeling. The stock electric fan does flow a lot better than the SPALs. I did look into running two stock electric fans. A RH and a LH drive. Couldn't come up with a RH drive fan. From memory, SPAL 10 inch ones are 800 cfm(??? maybe lower). Stock ones are 1100 to 1200 CFM. There are some SPAL 10 inch ones that put out a higher CFM. They don't quite fit. 

Once you get to about 45mph, the airflow from driving should exceed the flow of most e fans. The real test for e fans comes from idling in traffic on hot days with accessories on. The battery will provide reserve capacity but only at about 12v vs the typical 13.8-14 from the alternator. The performance difference is noticeable for e fans. Once the engine operating speed comes up, so does the alternator output and the fans may provide enough flow. 
 

The XJ/MJ just wasn’t designed to run all e fans on the stock cooling system. If the radiator capacity and efficiency is increased, the coolant passages are clean, the water pump flow is appropriately matched to the radiator capacity and engine size, then e fans could be used provided they can churn out sufficient flow under full alternator load at idle. But most setups simply can’t provide the CFM of the factory setup at idle. When idling, the engine electrical is basically at its weakest when the e fan load is at its peak. Many aftermarket manufacturers spec their fan CFM rates at specific voltage which are simply not attainable at idle with most stock MJ/XJ electrical system.