A8 Parts Forum  

Go Back   A8 Parts Forum > A8 D2 > D2 - Engine Bay

D2 - Engine Bay Everything under the bonnet

Reply
 
Thread Tools Display Modes
  #1  
Old 20th March 2018, 10:31 PM
steamship's Avatar
steamship steamship is offline
Senior Member
 
Join Date: Jun 2013
Location: Londonderry, Northern Ireland
Posts: 2,955
Default Will a Leaky Radiator Fail a MOT?

Trying to get a consensus on this before I proceed. My car has had a radiator leak for about a year now. Nothing significant, but I need to top it up every few weeks. The leak is coming from the very top right corner of the radiator where different materials appear to join.

Now, my mind has been on other things not car related for pretty much of the last year, so things like fixing problems isn't high on my agenda, if even on the agenda. The problem is that the car is due a MOT next month, I need to get it ready and the radiator is my one concern.

I have looked through the entire MOT inspection manual and can't find anything in relation to coolant leaks. Added to that is being in NI were the MOT centres are government run, and may play to a different tune.

I see three options. Take it the way it is and see what happens. Put something like Radweld into it, and lastly, fit a new radiator. Obviously the new radiator is what I'd like to do, as I want to give the entire car an overhaul, but I don't want to fit a new radiator and then a bit down the line have to move/remove it to work on other parts of the engine bay (and potentially damage it).

Radweld or something similar would be the next port of call, but I've read others caution the use of these products. I don't know if there is reason to be wary of them or just that some people think it will damage or clog other parts of the coolant system.
__________________
2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
Reply With Quote
  #2  
Old 21st March 2018, 07:06 AM
Architex_mA8tey's Avatar
Architex_mA8tey Architex_mA8tey is offline
Moderator
 
Join Date: Jan 2009
Location: London/Oxford/Swindon
Posts: 7,648
Default

Have you tried these guys Sean - they are radiator repair specialists, so might be able to repair your existing one?

https://www.brownlowradiators.com/product/radiators-2/

__________________

Confidence is the feeling you have before you know better . . . .
Audi A8 D2 3.7 Quattro Sport 1999 FL - Melange
2nd Place Winner - A8-Freunde Annual German Meet 2012 at Edersee
20" x 9" Bentley GTC Wheels with 385mm W12 Front Discs & Bentley Caliper Covers, Front Lowered on Coilovers, Xenons, Combined DRLs and LED Foglights to modified OEM front fog lamp position, Alcantara/Leather, Full Black Alcantara headlining + pillars and blind shelf, Bespoke Flat Bottomed Sports Steering Wheel, Dark Myrtle Wood, Autodim Mirrors, Bose, Blinds, Digital TV, Ski Hatch, Modified rear exhaust section for extra V8 Burble
Audi S8 D2 Final Edition 2002, Avus Silver with Red Leather Interior
Tiptronic with Sport mode button, Sony rear entertainment package, Bose sound system, Audi Navigation Plus, 20 inch Final Edition alloys, Full Cat Back Stainless Milltek exhaust, giving a great V8 burble
Audi A8L D2 4.2 Petrol with LPG - Ebony Black
Audi A8L D4 FL 4.0T Petrol twin turbo - Havana Black
Audi A2 1.6 FSi Sport - Dolphin Grey with Votex body kit and Red Leather Interior
and some other A8's A8L's and Mercs
Reply With Quote
  #3  
Old 21st March 2018, 08:29 AM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Posts: 5,017
Default

A leaky radiator is not an MoT fail. Its very common for radiators of that age to be weeping slightly. As long as its not dripping hot coolant on the tester's head it'll be fine.

Please don't put rad weld in it. It will clog up other parts of the cooling system. It settles at the lowest point of the system - in the D2's case, that's the coolant drain ports on the side of the block, and the heater cores.

A new radiator can be fitted without pulling the whole front end off, but its not the easiest job as you have to disconnect the power steering cooler which is messy. Usually the mounting bolts are seized so make sure new mounts are ordered at the same time. Often the snap nuts on the radiator shrouds are also seized so replace those too. I would advocate a genuine radiator or a Valeo if you can find one. The fitment on the Nissens is terrible.

Radiator 4D0121251R
Upper mounting 441121273L
Lower mounting 441121273K
Snap nut N 90419002
Screw N 90543801
Also have 2 x M6 nuts and washers and 2x M8 nuts on hand so you can cut the old ones off.

Last edited by MikkiJayne; 21st March 2018 at 08:44 AM.
Reply With Quote
  #4  
Old 21st March 2018, 12:24 PM
steamship's Avatar
steamship steamship is offline
Senior Member
 
Join Date: Jun 2013
Location: Londonderry, Northern Ireland
Posts: 2,955
Default

Quote:
Originally Posted by MikkiJayne View Post
As long as its not dripping hot coolant on the tester's head it'll be fine.


Quote:
Originally Posted by MikkiJayne View Post
Please don't put rad weld in it. It will clog up other parts of the cooling system. It settles at the lowest point of the system
And this is the very opposite place to where I need it to be!

Quote:
Originally Posted by MikkiJayne View Post
but its not the easiest job as you have to disconnect the power steering cooler which is messy
Is this the thinner radiator in front of the main radiator? If so, another reason for why I'd like to do this myself, as the last time a mechanic worked on the car, they damaged the top line of fins. No leaks thankfully. I won't really care if it takes two days for me to do it, so long as I don't break anything else in the process.

Doesn't the transmission oil flow through a pipe within the radiator as well (or is that something else)? If so, I also need to avoid too much loss, and then be able to top it up afterwards.

BTW Thanks for the shopping list of parts MJ. Best to have these now than having to chase them down later.
__________________
2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
Reply With Quote
  #5  
Old 21st March 2018, 12:46 PM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Posts: 5,017
Default

The thin radiator in front of the main one is the AC condenser. That swings out of the way to the passenger side. The PS cooler is the wiggly pipe in front of that.

Good point about the trans cooler - I forgot about that. The lines do indeed attach to the radiator, on the opposite side to the water hoses. You lose about 200ml taking the lines off - well within tolerance of the gearbox, but if you have the kit its prudent to check the level and top off if you can. Always replace the two o-rings on the ends of the lines, and make sure when they go back in they seat properly and aren't pinched. Lube them up with a bit of ATF and they should go in ok.

Trans cooler line o-ring N 90666001

A dremel with a tiny cutting disc is useful to cut the rusty nuts off the radiator mounts.
Reply With Quote
  #6  
Old 21st March 2018, 12:56 PM
steamship's Avatar
steamship steamship is offline
Senior Member
 
Join Date: Jun 2013
Location: Londonderry, Northern Ireland
Posts: 2,955
Default

Quote:
Originally Posted by MikkiJayne View Post
The lines do indeed attach to the radiator, on the opposite side to the water hoses. You lose about 200ml taking the lines off - well within tolerance of the gearbox, but if you have the kit its prudent to check the level and top off if you can.
Would you have a link to the kit necessary to do that? Since I also have the S8, it might be a wise investment, and a lot easier than trying to pour oil uphill.
__________________
2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
Reply With Quote
  #7  
Old 3rd October 2023, 09:04 AM
strummagnet strummagnet is offline
Senior Member
 
Join Date: Jul 2011
Location: Gosport
Posts: 400
Default

I am having to replace my radiator and note that it can be done without the front end being removed, and as I have small hands I think that may be an advantage? :

Quote:
Originally Posted by MikkiJayne View Post

A new radiator can be fitted without pulling the whole front end off, but its not the easiest job as you have to disconnect the power steering cooler which is messy. Usually the mounting bolts are seized so make sure new mounts are ordered at the same time. Often the snap nuts on the radiator shrouds are also seized so replace those too. I would advocate a genuine radiator or a Valeo if you can find one. The fitment on the Nissens is terrible.
Is there fluid loss from the PS cooler? This being the messy bit?

I cannot find a genuine (local ish) and not a Valeo either. Have seen a few MAHLE units online, would these be a good bet?

Also as I will be doing this on the drive is it best to put the car up on ramps for the underneath work? Will it affect the 'syringe' technique when refilling the ATF?
__________________
Paul
Gosport UK
________________________
Audi S8 2002 FE Avus Silver / Extended Red Leather.
Daily Driver: BMW 3 series GT - Just more practical for my camping trips!
Reply With Quote
  #8  
Old 3rd October 2023, 09:42 AM
MikkiJayne MikkiJayne is offline
Senior Member
 
Join Date: Jan 2012
Posts: 5,017
Default

There is fluid loss from the ps cooler and the atf cooler. Brake hose clamp tools are handy to block off the ps hoses to reduce the amount which escapes.
Laser 7254 Hose Clamp

All the non-genuine rads I've seen come from the same Chinese tooling. The Mahle one just has an expensive sticker on it.

Ramps will be fine and won't affect refilling the ATF
Reply With Quote
  #9  
Old 3rd October 2023, 09:52 AM
steamship's Avatar
steamship steamship is offline
Senior Member
 
Join Date: Jun 2013
Location: Londonderry, Northern Ireland
Posts: 2,955
Default

Quote:
Originally Posted by strummagnet View Post
Is there fluid loss from the PS cooler? This being the messy bit?
In a word, yes. In terms of everything else, MJ is the expert.

From a personal standpoint, and finally replacing the radiator five years after asking the question, my experience was somewhat different. I had the entire front end off the car, so can only comment on radiator fitment. I purchased a budget priced one, and the only fitting issue I experienced was the threaded stud used to hold the piece of plastic trim at the top of the radiator. I documented it all in the following post, but it's very long with lots of photos, but it's the black threaded stud in this photo:



http://forum.a8parts.co.uk/showpost....3&postcount=52
__________________
2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
Reply With Quote
  #10  
Old 3rd October 2023, 10:23 AM
strummagnet strummagnet is offline
Senior Member
 
Join Date: Jul 2011
Location: Gosport
Posts: 400
Default

Quote:
Originally Posted by MikkiJayne View Post
There is fluid loss from the ps cooler and the atf cooler. Brake hose clamp tools are handy to block off the ps hoses to reduce the amount which escapes.
Laser 7254 Hose Clamp

All the non-genuine rads I've seen come from the same Chinese tooling. The Mahle one just has an expensive sticker on it.

Ramps will be fine and won't affect refilling the ATF
Aha. I have clamps. Will ramp it and I will remove the front bumper - saw a chap on youtube do it.

Quote:
Originally Posted by steamship View Post
I purchased a budget priced one, and the only fitting issue I experienced was the threaded stud used to hold the piece of plastic trim at the top of the radiator.
I did spot a genuine one on tradition but getting it here safely (as MJ mentioned a while back) would be a challenge?

'Budget' radiator it is then.

Thanks guys.
__________________
Paul
Gosport UK
________________________
Audi S8 2002 FE Avus Silver / Extended Red Leather.
Daily Driver: BMW 3 series GT - Just more practical for my camping trips!
Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 05:24 PM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.