Vanagon External Oil Cooler Install - Rear Fender

[denwood]

I'm well aware. The Mocal thermo is well regarded, and used extensively in race applications. If it restricted oil flow as a result of the thermo plate, a lot of race cars would be blowing up..they're not. Will oil take slightly longer to warm up with the factory cooler deleted in cold weather? Maybe. Have I noticed any difference with respect to how quickly the oil comes to temp? Nope.

The most important change really is that I'm now able to use 5w30 synthetic, with well over 1 bar/1000rpm at full load/hot. 5w30 when cold obviously flows better than 20w50. I was unable to use oil at this viscosity before installing this external cooler, (previous oil cooler was coolant/oil) as when towing in summer temps, pressure was too low. Add in the Accusump that is installed for oil pre-pressurization, and this engine should last a very long time.

For someone wishing to stick with the coolant/oil cooler, the larger audi V6 larger cooler mentioned in another thread makes sense.
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Cheers,
Dennis Wood
The Grape

[1vw4x4]

If you follow the routing of the original oil cooler/heater, this device is
designed to heat the oil in cold weather. No place does it ever restrict the oil flow based on temperature. With this in place the oil is heated to the
temperature of the coolant, along with the heater cores.

[denwood]

SP1T SANDWICH PLATE 3/4 16 THERMO

That's what the thermostat/sandwich plate is for. That said, I don't drive it in winter. The van is showing very good pressure with 5w30 synthetic, which combined with the thermo plate would actually improve a lot on 15w50 in terms of winter operation. The transmission coolant/oil cooler and engine oil/coolant cooler have both been removed to improve reliability.
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Cheers,
Dennis Wood
The Grape

[1vw4x4]

How are you going to regulate the oil temps. in the winter, like the
factory oil cooler/heater does?

[denwood]

Just updating this thread with a recent pic. It does a better job of showing how the cooler is housed, and vents above the exhaust to low pressure:

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Cheers,
Dennis Wood
The Grape

[denwood]

My last post on the topic to wrap things up.

The road test was a pleasant surprise. First of all, I drove the crap out of the van tonight including a top speed run, hard highway hills at max throttle, and a few rpm/pressure observations. Oil temp did not exceed 100C. With 5w50 Castrol synthetic, oil pressure has increased from .3 to .5 bar (5-7 psi) across the rpm range as compared with hot pressure using the same oil but stock cooler.. With the accusump and oil cooler an oil change requires about 7 litres.

It's also obvious that the engine coolant system, now relieved of its auto transmission and oil cooling burden is more efficient. The fan did not come on at all during the run. At shutdown in the garage, the rad fan also remained off..the first time I've seen this after a hard run.

A side benefit of the oil cooler location is that AC condensate drains down the d-pillar and ends up running over the oil cooler. Not sure how much this helps, but it can't hurt, particularly as AC loading will increase engine heat load. At idle during my AC pressure test today, with fan on the fourth speed, a surprising volume of water drained out over the cooler.

So ends a month of oil/tranny coolers upgrades, intake muffling, AC rebuilding, Koni shock installation, and air/fuel tuning. The Westy has never run so well . Was great to get it off the jack stands tonight.
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Cheers,
Dennis Wood
The Grape

[denwood]

Those pics of the used bits look like Volvo 740 turbo.
_________________
Cheers,
Dennis Wood
The Grape

[buspor63]

[denwood]

Got the replacement cooler in place and all buttoned up. Here's the rear fender area with the cooler air shroud/shield in place. Basically you can't tell it's there unless you peak under the rear bumper where you'll see the air exit for the cooler. Note the nice new Koni now installed too. The rears were easy, the front a nightmare as the shocks in there did not have the allen head..it's a 6mm flat which is incapable of holding the rod as you back off the top nut. Ack. Ended up drilling a hole all the way through the shock so I could put a bolt through the shock/tube assembly and hold it from spinning.

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Cheers,
Dennis Wood
The Grape

[denwood]

If it isn't broke..don't fix it. After seeing what a 1/8 hole did to the Mocal, just make sure your cooler is well protected from a rock, failed tire etc. I'm also guessing you do zero driving in snow! That area is typically crusted up pretty good in winter. We do get a lot of snow here, and we do drive a fair bit on gravel in the summer..therefore the goal for my setup is a cooler that would be 100% protected in those scenarios.

Once I get the van back on the road I'm going to log some temps on the cooler to see how effective my flow predictions are. At 60mph the d-pillar intake vent drops off so I'm assuming the increasing low pressure at the rear of the van will compensate.
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Cheers,
Dennis Wood
The Grape

[midmo81]

Airflow is from inside to outside. Keeping this clean might be something to watch, but probably no worse than units mounted underneath. YMMV.

If I were doing this from scratch, probably would have taken easier location underneath somewhere. Since this was from some third or fourth PO way back, it seemed interesting for the work put into mounting the fan and coils this way. Out of the way when doing other fixing underneath. Like that ever happens.
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1981 AC Westy

[denwood]

If I understand this correctly, the rear tire dust/mud would end up on the cooler? Also, which way does the fan blow...into or from the d- pillar space?
_________________
Cheers,
Dennis Wood
The Grape

[midmo81]

Here is the rear fender cooler on my AC 81 Westy. Came with the bus from some PO install and all I had to do is replace the filter adapter, new hoses, new clamps, flush the gunk out of the coils, and fix the broken leaking exit fitting. There is a fan located behind it in the pillar.

It worked great in the 90+ degree heat this past summer. Sixty mph on the interstate with oil not over 220.
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1981 AC Westy

[denwood]

A drill stop would be good for these projects yes. Truthfully this was a rookie error due to a lapse in attention, so I will pay my fine and consider it a reminder. I should have been doing the tin work with the cooler removed, or at least the tube over the drill bit stop.
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Cheers,
Dennis Wood
The Grape

[morymob]

U can get 'lo-temp' alum rods to repair alum,weld supply, mine from a show,get cleaner/rods, small tip for propane torch and practice on alum can first. Make u a drill stop from old brake, gas line, plast tubing etc, fine adj depth by moving drill bit, won't drill thru other stuff.

[Zeitgeist 13]

Yeah, you're dealing with potentially 6 bar and up, while my boo boo was only around 1 bar -- big difference. Your application is probably best left to a professional solder repair. Bummer. I like your install. I plan on installing this Volvo Turbo cooler and thermostat on my eventual mTDI conversion

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Casey--
Volkswagens powered by Volkswagen
'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender VR6 -->2.5 TDI?
Oly Bulli
'87 300TD OM606 7mm Myna pump and HX30

[denwood]

Thought about fixing it, but given that it took about 30 seconds for 1 litre to exit at 1000 rpm, a leak at speed would have all 7 liters gone in 2 minutes or so. Now anyone who wants a Mocal to fix/play with..have I got a deal for you
_________________
Cheers,
Dennis Wood
The Grape

[Zeitgeist 13]

[denwood]

From the rear, the early tin work. The lighter aluminum sheet is just there for air flow, the 3/16" plate is there for protection from the rear wheel. You can see I've angled the oil cooler exhaust exit down a bit to make sure a low pressure zone will exist there at speed. We already know that the engine rear "air intake" vent louver has good positive pressure at speed...so I would predict very good flow thru the cooler, high to low pressure. You can also see why the oil cooler's heat output is completely isolated from the engine compartment.

_________________
Cheers,
Dennis Wood
The Grape

[denwood]

3/16" plate aluminum. It encloses/protects the oil cooler 100% and forms the air box that directs oil cooler "exhaust" to the low pressure area at the rear of the vehicle. Otherwise the cooler would be destroyed pretty quick back there. More pics later.

.
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Cheers,
Dennis Wood
The Grape