Tips: Your Td5 Oil Cooler

[Shackleton]

Utterly dejected at this stage but just for anyone's interest:

If you happen to want/need to check your oil cooler I have amassed some info from others and my own experience.

Firstly part numbers:

(you don't necessarily need all this)

Oil Cooler: PBC500230

Oil Cooler Gasket: ERR7220

Oil Cooler O-rings: ERR7098 (use this for centrifuge seal also)

Oil Cooler Bolt Washers: M22 Dowty Seals

Oil Filter Housing Gasket - LVH100230

Centrifuge Oil Return Gasket - LRJ100000

Oil Cooler Coolant Hose - PBH101980

There are two people I've found who claim to do longer lasting replacement items than the original:

Some fella called Marius in South Africa, if you google that you should find him.

And this crowd (who I've emailed but haven't heard back from yet) http://www.germistonhyd.co.za (maybe they're the same people?)

Britpart do the cheapest replacement heat exchanger kit for the cooler @ approx. £133 ex vat from Island 4x4. Next cheapest is Craddocks at approx. £149 ex. which they say is OEM spec.

My 10c:

I pulled my cooler because I had the engine stripped and it was just sensible to do so. I have 120k on the clock.

I had bought a new gasket, o-rings and dowty seals in the hope the exchanger would be serviceable. If you don't know, they've also been known to leak from the flattened o-rings while the cooler itself is in perfect condition.

I was pleasantly surprised when I got it off. The exchanger seemed to be in perfect condition. There was just one or two specks of white oxidation on one end and no signs of leaks. The rest of the unit was uniform reddish brown from the coolant.

I rubbed the white powder off. I was left with a pit in the surface which, as I watched, slowly filled with oil from the inside out. **** you sod's law.

So a couple of things:

1. There's (reportedly) a coating on the outside of the exchanger, if it gets nicked or scratched, that's where it'll corrode. If you take the cooler off the engine, and it's ok... kid gloves. Put it down gently and don't be tempted to clean it. The white oxidation is a death sentence though so I wouldn't recommend putting it back on.

2. Don't skimp on your coolant mix.

3. When breaking the seal between the cooler body and engine; it seems to be impossible to stop some coolant running into one of the oil ways on the block. It'll run directly into your sump. So basically don't crack the cooler unless you're prepared to drain/change the oil. I used twisted up rags to get into the oil way until the rag came out with only oil on it. I had the sump off anyway to check the oil pump bolt (which was loose but not unthreaded). When jacking the car up to get the sump past the axle, more coolant came out past the crank through the oil pump housing. i.e. out of oil ways.

4. As if it isn't well enough stressed already - regular oil changes. Sulphur builds up in oil making it more acidic. I've read about coolers corroding from the inside out. Who knows, could be bull**** or inconsequential. Seemingly this could also be exacerbated by low quality fuel with high sulphur content.

Cheers! My rebuild has ground to a halt because I've already spent nearly a grand on parts and consumables and I just can't afford a cooler for the time being.

[Team Idris]

In the CAD drawings section of the forum I've posted the hole pattern for the ally housing if anyone wants to blank the block off and run an air cooled oil cooler. (Or none).

I come across this oil-cooler in water design regularly and its always trouble. Normally they are in the header tank of the rad.

If it is working well it keeps the oil warm as well as cool, but on our TD5 it bunged everything up until the rad hoses blew.

I hope you can get yours fixed in the end

[Shackleton]

Thanks mate.

I did consider that... I mean replacing with an air to oil cooler, and I'm off to look at your drawings with faint hope, but I've a feeling it might be out of my tooling range at the moment. I even saw that HFH is selling a Mocal cooler atm.

EDIT: yes mate way beyond my resources here, which is disappointing, but fair play and thanks. (did you actually carry out this mod in the end?)

[Team Idris]

No

Hours wasted is just normal at Team Idris

I used the cnc stamp at work to make a steel gasket, (for want of a better description), to check the drawing was right. I was thinking folk could get one water jetted or laser from 10mm ally. Or print a 1:1 paper template and drill one? But in our case we had the cash to buy a lower end replacement, once we found one, but after I started on project by-pass.

[Shackleton]

Was just out at the workbench giving the broken heat exchanger the fingers.... and had an idea. I took the two exchanger bolts (with the holes in them) and put them through the holes in the cooler casing, but from the inside out - thus making fittings for an external cooler. The only problem is that there's very little room for clearance on the aft one coming past the oil filter cartridge. It'd need a very slender 90º union, or a banjo would probably be best.

Do you know:

The thread size of those oil cooler bolts and whether it's a standard union size (or how I measure thread size)

Is there an off the shelf, 90º or banjo union for this size?

Would the standard oil pump have the legs to pump through an external air cooled cooler? (given it'd prob need to be on a decent length of feed and return pipe to get it away from the turbo.

[Shackleton]

Help!

I've been in contact with Paul at Germiston Hydraulics. He's giving me a good price on a replacement oil cooler - R3000 including shipping from South Africa to Ireland. (that's about €204)

I've asked him what makes their cooler superior to the OEM item. He says it's machined from a solid billet and is approx. 10x thicker aluminium than the original. He says it cools better due to it's greater number of fins.

A chap on another forum bought one of Paul's coolers. He was happy and posted the pics below, commenting that it was extremely well machined and very robust.

I'm just a little worried - thicker is great, but 10x thicker? Especially seeing as it seems to be a ribbed block, rather than a finned item that allows coolant run in between separate sections. I look into the OEM there are lots of little internal fins too.

I want to take a punt on it, the price is right and I don't doubt it'll last longer, but a second opinion on whether it will cool properly would be great.

[Team Idris]

I'll stick my neck out and say the internal fins are more for low speed oil.........Although, if it's just one drilling to join inlet and outlet together I think it might struggle? Multiple cross drilling would be okay. Billet will be strong and resilient.

Oil needs the greater surface area being chains rather than individual H2O molecules. If you use an oil cooler with antifreeze water you see an increase in power dissipation for the same temperature and flow. It just does it better.

I wonder how upset the oil would be if you cut the ports off the old cooler and replaced with a simple tube? The more I looked at dry sump I could see that the last main bearing probably got oil at the block temperature, regardless of what it left the filter at. And that cooling the oil is best achieved before it gets to the pressure pump. The best place for a rad-water powered oil-cooler would appear to be in the sump

[Ohlins]

That looks like the same form of cooler that my 3.2 DiiD Pajero has....so I personally wouldn't see any problem with fitting it.

Also,the South African dudes are using them in higher temperatures and don't seem to report any problems to date?

.

[Shackleton]

Looking back I'd say it's a decent option, simple to engineer and plenty of sacrificial meat if you do happen to have a stray earth or poor fluid in the cooling system.

Another tip that I learned the hard way since changing mine (after it had filled my cooling system with oil); I was flushing the system every other day after covering varying mileage, and when refilling was adding a crushed dishwasher tablet each time. That seemed to do well at cleaning the oil from the internals, although who knows. But after maybe 8 flushes I realised that some sludge would never make it all the way down to the drain plug and was just gripping the inner walls of the cooling system, only to float back into the expansion tank when I refilled. So I'd been going round incircles to a certain extent.

A full flush was no longer worth it, and at that point I put in the proper mix of coolant for keeps. It still needed a thin layer of scum removed from time to time but the trick is to raise the expansion tank, pull the return pipe, and the outflow pipe from the bottom - they won't leak if you keep them elevated just a little, and drain the expansion tank only. Then rinse it out with a thinner and it comes up spanky.

[Maverik]

For info ERR7098 is an o ring with ID of 25mm x 3mm thick.

[Deffy]

Hi Shackleton,

Just wondering how that oil cooler from Germiston Hydraulics is going for you? I just got mine and am about to install in the next few weeks. Would really appreciate your verdict!

[Shackleton]

I didn't go with the Germiston item in the end. I just couldn't see it cooling as well being solid, there's no doubt it's way more robust. I bought an OEM type one and it's been 10% ever since. I do believe though that it's imperative you keep your coolant as specified and that there are no bad earths on your engine.

I should say, I found another chap in S.A. who sold me a cooler he made up from copper and steel fittings. When I say it like that it seems like a no brainer but when it arrived it was totally unfit for purpose. He gladly waived the fee, which was fine. The moral being just go buy a standard OEM from wherever you see fit and save yourself a lot of wasted time.

Hope that helps.

[Troll Hunter]

It seems that dishwasher tablets in an aluminium cooler are not a good idea, since they are generally caustic, and can/will rapidly attack aluminium, apart from achieving their purpose of removing oil.

Mike

[Deffy]

Thanks for the advice Shackleton. I might have a rethink!