Lotus Oil Line Repair

Lotus Elise and Exige cars built from 2005 to 2007 are subject to a Lotus recall for faulty oil cooler line fittings. The OEM oil lines are of decent quality and are reinforced. The problem with the lines is isolated to poor crimps at the fittings. In addition to poor crimps on the fittings, we don’t care for the hard 90 degree bends and prefer softer tube bends for better flow and less pressure drop.

While there are available replacement oil cooler lines in the aftermarket and the option to do away with the front coolers in favor of a rear cooler, one could simply replace the OE fittings. The following tech article details how to replace the fittings with vastly superior parts that WILL NOT FAIL. Installation isn’t that tough. It is time consuming, but it’s quite inexpensive (relative to alternative aftermarket solutions), and is arguably a good project for the DIY’er. To complete the job you’ll have to remove the front clam. However, you can replace 4 of the 6 fittings with the front clam in place. Use your best judgement.

Things you need above and beyond the “basics”:

1) Heat Gun
2) 2 90 degree 5/8 BSP to 5/8 hose barb fittings: Available for a few dollars at http://batinc.net/mocal-central.htm
3) 4 45 degree 5/8 BSP to 5/8 hose barb fittings: Available for a few dollars at http://batinc.net/mocal-central.htm
4) 6 hose clamps. Worm-drive or Oetiker are acceptable: Oetiker clamps and crimping tool available at: http://batinc.net/mocal-central.htm
5) Hose Cutter
6) Oil drain pan
7) Mechanics gloves for heat insulation
8) WD-40
9) 46 inches of AN -10 (5/8) high pressure hose

For illustration purposes, we’re going to replace one of the rear fittings below. You’ll obviously need to remove the rear access panel (under-tray) to accomplish this. For the front, you can access two of the 45 degree fittings by removing each wheel well. To replace the final two 45 degree fittings for the connection line between the coolers, you’ll likely need to remove the front clam. You should replace the length of hose across the front with a new 46 inch length of hose and your new 45 degree fittings.

Step 1: Locate and remove the oil fitting. They can be quite tight so be sure to use two wrenches and hold the contra fitting.


Allow oil to drain a bit.


Step 2: Pull some slack from the side sill as shown and drop the oil line down so you have room to work



Step 3: Cut the fitting off flush at the collar



Step 4: Locate a 90 degree fitting from BAT and a clamp. Note the deep barbs on the fitting. Do not use fittings with shallow barbs. Both styles are available so be sure that you get the “Push-Lock” style with the deeper barbs as shown. Oetiker clamp pictured (Oetiker clamps require a special tool for crimping)



Step 5: Slip the clamp over the tube. Put your gloves on and heat the rubber hose. The hose needs to be VERY hot, way too hot to hold with a bare hand, so that it is pliable enough to expand over the fitting. Apply WD-40 to the inside of the hose and fitting barbs just before installing. It takes a LOT of effort to get the fitting in the hose. Once you start inserting the fitting, don’t stop or you’ll get stuck with a fitting half installed. Don’t panic if this happens. There’s enough hose for at least one do-over…



Step 6: Finishing touches. Rotate the fitting so that it’s aligned with the port, secure your clamp, and reinstall. You’re done with this one and can rest assured it’s a lifetime fix! The reality is that the hose clamp is not really needed. However, it’s good insurance in the event that the hose gets soft many years from now.