Club 80-90 Forums

Simple question.

During install I damaged the water cooler just between oil filter and housing. I have purchased a new one and notice one side has dimples and the other best down this and due to me not having any info with me can someone tell me if the unit has to go on one way only.

Cheers

Dickspanner

Bentley manual does not specify it has to go a certain way.

WBX?

Oil cooler...coolant warms to 90 - 95C the oil gets much hotter, 120C plus...tis the coolant that cools the oil and not tother way round.


Martin

I never knew that

Funny that
When I first got my 2.1 WBX about ten years ago I knew the engine was a bit loose and I would be towing and launching boats. So I fitted a remote thermostatically controlled fan blown oil cooler from Kenlow (who now only deal with the trade - big time incidentally). This must have done a good job as I got another two very active years before it started to rattle and had to be rebuilt.

However one of my advisories this MoT was a small oil leak from the area of the oil filter. I had plumbed the Kenlow unit to a Kenlow supplied adapter between the oil filter and what I must of thought at the time was the crankcase. So anyway I set out and fixed the leak.

This time however I noticed noticed that something else was fitted under my Kenlow adapter which somehow seemed to be connected to the coolant system. This puzzle being the least of my priorities at the time I fixed the leak and promised myself to check it out in my Bentleys.

Looking at the excellent images associated with this thread however I am embarrassed to realize that I probably already had an integral oil cooler all along.

Do! Must check stuff like that out in the Bentleys before I dabble

CS

PS It does aggod job so I am leaving it in.

Thanks for advice and picture. Now all fitted. Just got to get fuel and wiring g sorted and its ready for firing up.

The secret to a long life on these engines is to control the oil temp properly. The main failing of the 2.1 would appear to be big end failure.

The big end failure is thought to come from a build up of heat in the oil from hard usage, which causes a corresponding drop in oil pressure. if the oil goes over 120 deg C then the pressure drops rapidly, and the big end bearing furthest away from the pump suffers from limited oil supply, and then usually gives out.
VW realised that there was a problem and put the generic oil cooler/warmer on the syncro's and 2.1's. This device is also thought to work better as a warmer (because there is a bigger heat difference between cold oil and warm water, than hot oil and hot water) CS, "So an after market oil cooler with thermostatic (80deg.C) control included isn't a bad idea."

Personally my low compression MV engine oil temp. rarely goes above 104C (unless I drive it over 80mph) so I've not fitted one. DJ's, being high compression engines, run a bit hotter. Oil Cooler recommended.

Correct oil temp in the engine should be over 100C and up to 120C. You want the oil to be above the boiling point of water so as to keep the oil free of the water generated in the engine due to the combustion process.

DoubleOSeven wrote:VW realised that there was a problem and put the generic oil cooler/warmer on the syncro's and 2.1's.

I'm afraid not, it's to get the engine to full operating temp so the FI will go into closed loop quickly in order to lower the overall emissions profile, mainly for what at the time were more stringent markets like the US, but eventually other countries as they also raised their standards. Once car engines got lambda and the three-way cat, manufacturers found that the engines run extremely clean in closed-loop mode, so the preponderance of actual emissions occur during warmup. So starting in the early-mid 80's you see features designed to decrease warm-up time, including water-to-oil heat exchangers because oil will take three times longer to reach temp as the coolant. You see the hx's added to more and more of VW's various engines around then, and other manufacturers used similar strategies.

(Meanwhile the notion of VW becoming aware of an engine problem that doesn't materialise until over 150k miles, and then actually DOING something about it is, no offense intended, laugh-out-loud funny)

This device is also thought to work better as a warmer (because there is a bigger heat difference between cold oil and warm water, than hot oil and hot water)

On this point you are absolutely correct, and conversely there's little capacity to "cool" the oil because the temp differential is small when both fluids are hot, and the hx itself is tiny and has very little internal surface area. The hx will bring oil temp back down close to coolant temp slowly after hot excursions, but at sustained high roadspeeds the high engine rpms will add heat to the oil faster than the hx can remove it, so oil temp will climb higher, with the resulting drop in oil pressure (oil temp is mainly a function of rpms, coolant temp is mainly a function of load).

"So an after market oil cooler with thermostatic (80deg.C) control included isn't a bad idea."

Indeed, it is a very good idea. The more highway miles you drive and the faster you drive them, the more you need it.

I fitted one to my DG which has an oil temp gauge and it did bring down the peak oil temp significantly

(Meanwhile the notion of VW becoming aware of an engine problem that doesn't materialise until over 150k miles, and then actually DOING something about it is, no offense intended, laugh-out-loud funny)

Car manufacturers don't design and manufacture an engine, then send it out to market. They test it to its limit including doing high mileage on it, prior to release...in order to iron out said problems.

But thanks for showing so much interest in my post


Sent from my iPhone using Tapatalk