DIY - How to save your oil cooler

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Mɐʇʇ
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DIY - How to save your oil cooler

Post by Mɐʇʇ » Fri Jan 16, 2015 10:47 am

The union between the oil cooler and the oil pipes on our cars isn't great design - aluminium cooler to a mild steel union, you usually end up mashing up the thread on the cooler when unbolting the union. This is my repair - and how to leave it with a fitting on so it's easy to remove in future without more aggro.
Apologies for the lack of photos - I didn't think about this being useful until "after" the event and I'm trying to avoid taking everything apart again.

The Problem
The M22 x 1.5 threads on the RHS of the oil cooler are mashed up by the mild steel oil pipe fitting.

The Solution
I found that there is still some good threads left on the oil cooler beyond where the steel fitting screwed (perhaps 5 turns) - this gives us something to work with.

Step 1 - Buy these.
1x M22 x 1.5 Female Socket : http://www.ebay.co.uk/itm/301178655701
$_12.JPG
$_12.JPG (11.32 KiB) Viewed 8790 times
2x M22 to AN10 adaptor (The shorter Setrab one as per here - there is a longer type also) : https://www.ebay.co.uk/itm/382268993413
$_12 (1).JPG
2x AN10 45 Degree Fitting : http://www.ebay.co.uk/itm/150781418512
$(KGrHqYOKpsE3tk9Qzu2BOE0gqvYUw~~_12.JPG
1 metre AN10 : Stainless Steel Hose : http://www.ebay.co.uk/itm/360881217559
$(KGrHqV,!pEFJCqk,1+dBS(p18gn2Q~~60_12.JPG
AN-10 Separator : http://www.ebay.co.uk/itm/360929317656

(FWIW - I've bought loads of fittings from Torques UK - the quality is great, the range is excellent and their service pretty damn good too. I recommend them)

Step 2 - Clean up the remaining threads on the oil cooler and make sure they're not full of swarf/oxidisation and fully degreased. Stuff a blue Shop towel (not rag) down the open end to make sure you don't get any swarf etc in the end.
Screw on the M22 Female socket. It will need some adhesive - you could perhaps use thread lock, but I I decided I want this socket to be a permanent fitting on the cooler and I've found JB weld to be the best consumer epoxy I can lay my hands on.

Step 3 - Unscrew the oil filter end of the existing hose and the adaptor - you will need to remove the OS intercooler hose.

Step 4 - Screw in the new M22-AN10 adaptor into the oil filter housing. Make sure you include the o-ring - or possibly you may want to replace it with a 22mm copper washer and a littler sealer.

Step 5 - Make up one end of the hose with a 45 degreee AN-10 fitting on. There's loads of guides how to do this well, so I won't cover it here. Make sure the internals of the hose are really clean. (FWIW, for cutting hose I recommend binding the hose with electrical insulating tape and cut it in the middle of the tape with an angle grinder with a 0.8mm cutting disk).

Step 6 - Temporarily route the hose through and hand tighten on the oil filter end. Measure up the length of the finished hose to the oil cooler using the 2nd 45 degree fitting. It is approx 0.7m IIRC.

Step 7 - Make up the finished final hose end. As above - make sure it's super clean internally.

Step 8 - Final install it and use the separator to mount it tidily. The new An-10 hose is a little large than the old hose, so it is a little tight - but it's fine.

Step 9 - Have a beer and congratulate yourself for saving several hundred £££ on the cost of a new oil cooler and various hoses (Because you know you'd have to replace a bunch of other hoses too when replacing the oil cooler!)
IMG_3687.JPG
Final thoughts:
  • I used the standard AN-10 Oil and cooler hose just because I have some stock from other projects. It fits well, but is a little tight @ 20mm diameter. If you use teflon hose, it's 16mm diameter so might give a little more room to maneouver. Check which fittings you'd need if you go down this route - they may be a little different too.
  • In the oil system, cleanliness is paramount. Before hooking up either end of the hose, be really careful to make sure the hose is super clean. Just because this hose is before the oil filter is no excuse - oil filters have a bypass valve in them, so not all the oil goes through the filter, especially when cold!
Last edited by Mɐʇʇ on Thu Jan 18, 2018 8:58 pm, edited 4 times in total.
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SuprSi
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Re: DIY - How to save your oil cooler

Post by SuprSi » Fri Jan 16, 2015 11:02 am

Awesome guide! Thank you :bowdown:

We need Shopp to link to this in the DIY resources thread.
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Re: DIY - How to save your oil cooler

Post by C_J » Fri Jan 16, 2015 1:44 pm

Brilliant!
Defo deserves to be a sticky!
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Re: DIY - How to save your oil cooler

Post by seaneb » Fri Jan 16, 2015 6:40 pm

Sticky please. Thank you MattYorke. :thumbs:
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Re: DIY - How to save your oil cooler

Post by zippy » Fri Jan 16, 2015 7:30 pm

Fantastic guide ! Thanks :)

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Re: DIY - How to save your oil cooler

Post by Shoppinit » Fri Jul 03, 2015 8:04 am

FAQ'd
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Re: DIY - How to save your oil cooler

Post by Classik » Fri Jan 18, 2019 3:10 pm

I'd like to thank the OP for sharing this: I've had the work done a few months ago and works like a charm. But now I need to do the same on the other side which is also leaking: oil line 4B3317815B, part #3 on the image below. :?

Does anyone know if the other side of the oil line where it joins part #1 is also an M22x1.5 thread (see red arrow) ?

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Re: DIY - How to save your oil cooler

Post by Mɐʇʇ » Fri Jan 18, 2019 3:21 pm

Thank you. :)
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Classik
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Re: DIY - How to save your oil cooler

Post by Classik » Fri Jan 18, 2019 4:10 pm

The proof: ;)

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RS6 C5 Avant 2003 Daytona Grey
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Re: DIY - How to save your oil cooler

Post by Mr Footlong » Wed Nov 13, 2019 5:39 pm

Balls.... So, I ordered all of these bits last week, to drop to the garage while the car is there. Everything turned up except for the M22x1.5 female brass socket. Chased today and they have just told me on backorder and will be at least 2 weeks. Of course, the garage aren't happy and want the car done and gone!

I have had a quick hun and not found any of these anywhere. No chance anyone has one of these spare that they want to sell, or happen to know where these can be bought from other than eBay, that would be great, thanks :).
Current:

"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm

Gone:
"Taz"- C7 RS6 - MRC stage 2 - Milltek non-res + 100 cell cats, uprated fuel pumps, race plugs, 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.

Mɐʇʇ
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Re: DIY - How to save your oil cooler

Post by Mɐʇʇ » Wed Nov 13, 2019 5:54 pm

I'll have a hunt
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Classik
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Re: DIY - How to save your oil cooler

Post by Classik » Wed Nov 13, 2019 6:35 pm

Got one spare here that I'll happily give for free to help a forum's member. Problem is the distance (I'm in Paris), but if you don't find an easier option, you're welcome to PM.
RS6 C5 Avant 2003 Daytona Grey
Loba 650 turbos - Wagner IC - 200 cells cats - Milltek cat-back - Hotchkis bars - Bilstein B16 - MTM Wheels - oem coolant cap

Mɐʇʇ
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Re: DIY - How to save your oil cooler

Post by Mɐʇʇ » Wed Nov 13, 2019 6:49 pm

"not a professional engineer, mechanic and mechanist"

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Mr Footlong
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Re: DIY - How to save your oil cooler

Post by Mr Footlong » Wed Nov 13, 2019 6:54 pm

Matt, that is the same seller from eBay, but their normal site. No stocm for 2 weeks.

Clasik, the way things are looking I may well need to beg you in the morning. Happy to pay you whatever you need of course, thanks :)
Current:

"Brutus"- C5 RS6 Avant - MRC stage 2 - Milltek non-res + 100 cell cats - Wagner ICs - PSS9 - H&R ARBs - OZ Superturismo LM - C6 Custom brakes - HD RNS-E - Various other bits - 555PS/832Nm

Gone:
"Taz"- C7 RS6 - MRC stage 2 - Milltek non-res + 100 cell cats, uprated fuel pumps, race plugs, 745PS/1095Nm
12' Cayenne Turbo, B7 RS4, S3, Cupra R, XJR, EVO VII, STI8,5,2&WRX, 106 GTI&XSI, other crap.

Mɐʇʇ
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Re: DIY - How to save your oil cooler

Post by Mɐʇʇ » Wed Nov 13, 2019 7:00 pm

"not a professional engineer, mechanic and mechanist"

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