Vanagon remote oil cooler installation (long; w/pics)

[tencentlife]

I recently upgraded the 2.1 wbx in my '87 Vanagon GL to a 2.2, which now has a few thousand miles on it. Detailed build list in my previous post here:

http://www.shoptalkforums.com/viewtopic ... 8c9231aaf3

Now further upgrades are in order. I'm of the school that believes that these engines need additional oil cooling if they are to be driven at all hard. The OEM oil-to-water exchanger is called a cooler, but it would be more accurately described as an oil tempering device. It is very helpful as an oil warmer, because the coolant temp rises much faster than oil's, and oil is a poor lubricant when it isn't in the right temp range, hot or cold. Many studies have shown that a great deal of the total wear in an engine occurs during warmup, when lubrication is still less than optimal. For that reason, I'm keeping the OEM exchanger.

I have an oil pressure gauge installed (oil temp is newly installed, but I'm waiting on a proper sender, which will be the subject of another post). Driving the van hard in hot weather, especially with AC on, oil pressure is usually around 40psi. But when the water temp starts to rise, indicated by as little as one needle width change on the stock water temp gauge, pressure quickly falls to as little as 25psi. To me, this is unacceptable. I have a new bottom end with .001" clearances in all bearings, and I intend to make it last a long time.

So I came up with an installation that doesn't require a fan to cool the oil, but rather takes advantage of an available forced-air stream in one of the rear pillars of the car, since extra cooling is only really required when the car is being driven hard. The left D-pillar is full of AC hoses, but the right is wide open. I had already removed the unneccessary and problematic idle speed control system, as well as the restrictive intake air duct that was in the right D-pillar. I mounted a 48-plate Mesa cooler at a 45deg. angle in the right taillight recess, top tilted in and fittings aft, so that it filled the vertical space.



Then I created an airbox, by making a divider of 1/4" polycarbonate sheet, which blocked air from flowing around the cooler. The airbox divider also has a hole to accept a 3" flex hose, which is routed to the stock air filter housing with a 2 1/2" adapter.





A Mocal thermostatic sandwich adapter takes oil from the filter and routes it to the cooler once oil temp exceeds 180deg.F. The two hoses are Aeroquip 1/2" ID "socketless" hose, and hose fittings are AN-8 anodized aluminum spin-ons. I used steel fittings for the NPT to AN-8 adaptation, since the anodized ones look nice but are needlessly expensive. The hose came in a pretty blue, which matched my Ford blue engine block nicely.



Hoses are routed up the front of the left cylinder bank and diagonally over the engine bay. The outbound hose is 52" long, return 62", for a total round-trip of less than 10 feet.



Here is a template for the airbox divider parts. The two parts are joined by a 9" length of 3/4" angle. Lengths of angle also attach the divider to the rear edge of the cooler frame, and the forward edge of the cooler to the front wall of the taillight recess.



I installed a thermostatic fan switch inline at the top cooler fitting, in case I ever wanted to add a small fan, but I don't think it will ever be needed. It is the hottest month of the year, and in hard driving my oil pressure is staying in the low 50's with 15w40 Delo. I have a Trasko depth/bypass filter that drops pressure about 8psi typically. My readings are of course taken from the main galley after the flter. Climbing a notoriously long, steep grade on I-25 the other day, a hill that eats air-cooleds alive, pressure fell to about 48psi. Soon I'll also have a temp gauge reading, to make sure the cooler isn't doing its job TOO well.

There are other pics here:

http://s105.photobucket.com/albums/m218 ... tallation/

[tencentlife]

Got the new oil temp sensor awhile ago. I installed it in place of the reducer bushing that normally holds the dynamic oil pressure sensor, in the rear of the main oil galley (M16 x 1.5 thread. VDO part #323-056
http://www.egauges.com/vdo_send.asp?Sender=300F_150C )



The high pressure sender was ganged up with the other oil pressure senders above the T-stat manifold, visible in the engine overhead view above.

The temp sender is measuring oil at the ideal location: right before it goes up the galley to the bearings. Now that I've put some hard miles on it, I can say that this is working very well. Oil temp is usually at about 210-215deg.F, and maxes out at 220. Pressure is amazingly stable at cruising speeds over 2500rpm, maintaining 45psi+ hot, and usually closer to 50. Cold start pressure is not over 65. I'm using a stock sized oil pump and a new OEM relief valve spring.

I didn't have temp measurement before, but I can only assume that it got much hotter, as I used to see pressure drop down to 25psi, even with the 80C water T-stat. The oil pressure is so stable now that I switched back to the OEM 87C T-stat. Max temp went up to 225 one time since then.

I think this is going to have terrific benefits for engine life.

[tencentlife]

I finally added fan cooling to this rig. It was never needed for road cruising, but I noticed on some long low-speed climbs while exploring forest roads that the OT got up to 230F, a bit higher than I like. I had these muffin fans around so I made up some bracketry to mount them to the cooler, and they're switched by the inline 180F thermoswitch I had already put in the top oil line. Dunno how long the fans will last as they're not weatherproof, but if they fail I'll go to a small fan designed for automotive use. They have in total about 170cfm, and they do the job. At low speeds the oil stays under 200F:

Here's the brackets on the fitting side:


A little shrouding over the top of the top fan to get a better seal:



Several people have been interested in duplicating this arrangement, so, since I had the cooler out, here's a couple detail shots of the mounting rails and blockoff plate:


This shows the thin strip that spaces the blockoff plate away from the body gusset. There's another piece of aluminum angle joining the strip to the plate, and long screws hold the assembly up in place:

[lanhet]

Hi tencentlife !

Very interesting project. Having been raised on old British bikes, I am also a firm believer in oil temperature control. I retired this fall and bought a really neat '90 Westy. I have already done a few improvements and I am planning to do more over the winter. I was doing some research on oil coolers when I came across your post.

My Westy doesn't have A/C so it would be much easier to install the radiator and fans on the driver's side of the van. It would also make for much shorter and neater hose runs. On the other hand, I was wondering if keeping the original "heat exchanger" was a valid choice in my case. I live in Canada and the van will never be driven in cold weather, when bringing the oil to operating temperature as quickly as possible is a good idea. I have a hard time convincing myself that the flimsy looking exchanger and the added complexity are really worth the trouble. For that reason I am considering your mod without the exchanger.

I would appreciate your opinion on the subject. If I ever decide to do without the exchanger, is it possible to find a shorter mounting tube to compensate for its absence?

Thanks in advance

[tencentlife]

I get asked this often and you will understand the problem you face if you hold the sandwich adapter up to the O/F flange without the OWHX; now find the fittings you will need to get the oil lines off the sandwich adapter.

[jackstraw]

Mocal has a nice site. Easy to navigate. Just may have to check into this.

I'm still an aircooled Bus pilot but nonetheless.

Thanks for the write up.

Any tips to properly clock the adapter or does the mounting bolt let this happen

[buildabiggerboxer]

Hi tencent, that good work has recovered the oil pressure to a much more bearable level then?, it will be good to see how it translates into actual wear reduction. ive gone over to electric coolant pumping on my race motors, to help keep oil temps down to 100 /110c , and pick up some 'free' power of course, but its very cold here at this time for meaningfull testing, roll on spring time.

[tencentlife]

Hi tencent, that good work has recovered the oil pressure to a much more bearable level then?,

I tended before to look at pressure because that was what I had a live measure of, but lowering pressure was of course just a proxy for climbing heat. So you could say that pressure was never the real problem, only a secondary symptom. What the cooler has done is keep oil temp at a bearable level. Having taken care of that, pressure has taken care of itself.

it will be good to see how it translates into actual wear reduction.

Had the same engine opened up recently, with about 45k of hard driving on it (I flog my Vanagons like nobody else), freshening up the top end while swapping it into my Syncro, and I took a peek at #3 rod bearing. It looked almost-new, all the babbitt was completely intact, no scoring, the only way you could tell it was used was it was a bit shinier than they come out of the box.

Some of you guys may already know, I have been selling Vanagon oil cooler kits for a few years now, based on this concept but with many refinements. There are variations for fitting in all Vanagons with any wbx (1.9, 2.1, and Syncro each have their own kit), and most of my engine jobs go out with the cooler, plus I've sold a couple dozen more kits apart from engine jobs. They are good kits, complete and easy to install, and have been very well-received by my customers. You can find out more and contact me thru this link:

http://www.thesamba.com/vw/classifieds/ ... ?id=514460