OEM Oil Pipes - Swapping Between Rubber and Metal

OEM Oil Pipes - Swapping Between Rubber and Metal

Author
Discussion

ColourRestorer

Original Poster:

34 posts

80 months

Thursday 10th June
quotequote all
Can anyone clarify the thought process behind the design of oil transfer pipes in road cars?

My assumption is that the design criteria are:

Ability to withstand temperature and pressure of fluid being carried.

Cost.

Weight.

Space/Volume.

Ability to withstand environmental conditions including abrasion, vibration, salt spray and a few other things listed in 810E.

Resistance to transmit vibration between components.

Ability to withstand relative motion of differently mounted components e.g. engine and bodyshell.

Inclusion of joints to allow maintenance.

Oh and did I mention cost?


Why am I asking this? I am repairing a road car which has suffered a catastrophic transmission failure with the result that the oil lines and oil coolers will need to be replaced due to contamination. Added to which, many of the lines were assembled without anti-corrosion coatings so cannot now be separated from the coolers.

The OEM lines are a mixture of aluminium and what I'll simplistically describe as rubber and seem to interchange between the two materials at various points along the hose runs for reasons which I cannot fathom.

The cost of OEM lines is ridiculous (£200+ for a 2 foot line), and there are eight of them, so my instinct is to replace the lines with long simple runs of braided hose, but I’m wondering if there’s a factor, or indeed many factors, which I have overlooked.

Your thoughts please...


GreenV8S

28,860 posts

251 months

Thursday 10th June
quotequote all
Metal lines may take a few fractions of a second less time to install on a production line. There may be logistical reasons to split lines up to make it easier to install. I doubt the manufacturer cares about corrosion as long as it doesn't cause warranty claims or bad press.

stevieturbo

15,488 posts

214 months

Thursday 10th June
quotequote all
ColourRestorer said:
Can anyone clarify the thought process behind the design of oil transfer pipes in road cars?

My assumption is that the design criteria are:

Ability to withstand temperature and pressure of fluid being carried.

Cost.

Weight.

Space/Volume.

Ability to withstand environmental conditions including abrasion, vibration, salt spray and a few other things listed in 810E.

Resistance to transmit vibration between components.

Ability to withstand relative motion of differently mounted components e.g. engine and bodyshell.

Inclusion of joints to allow maintenance.

Oh and did I mention cost?


Why am I asking this? I am repairing a road car which has suffered a catastrophic transmission failure with the result that the oil lines and oil coolers will need to be replaced due to contamination. Added to which, many of the lines were assembled without anti-corrosion coatings so cannot now be separated from the coolers.

The OEM lines are a mixture of aluminium and what I'll simplistically describe as rubber and seem to interchange between the two materials at various points along the hose runs for reasons which I cannot fathom.

The cost of OEM lines is ridiculous (£200+ for a 2 foot line), and there are eight of them, so my instinct is to replace the lines with long simple runs of braided hose, but I’m wondering if there’s a factor, or indeed many factors, which I have overlooked.

Your thoughts please...
There are always factors. You wish to change them, you deem whether your choice of hose now meets your criteria.

9xxNick

760 posts

181 months

Thursday 10th June
quotequote all
A company such as Pirtek may be able to make you up some hoses to the correct spec if you take the old ones along. They also have a mobile service.

ian332isport

84 posts

198 months

Friday 11th June
quotequote all
9xxNick said:
A company such as Pirtek may be able to make you up some hoses to the correct spec if you take the old ones along. They also have a mobile service.
Possibly.

Car manufacturers have an annoying habit of using non standard threads/fittings, so the likes of Pirtek may not be able to help. Worth a try though..

ColourRestorer

Original Poster:

34 posts

80 months

Friday 11th June
quotequote all
stevieturbo said:
There are always factors. You wish to change them, you deem whether your choice of hose now meets your criteria.
Thanks for that insightful response.

ian332isport said:
9xxNick said:
A company such as Pirtek may be able to make you up some hoses to the correct spec if you take the old ones along. They also have a mobile service.
Possibly.

Car manufacturers have an annoying habit of using non standard threads/fittings, so the likes of Pirtek may not be able to help. Worth a try though..
Thanks both Ian and Nick.

We've got a local mobile hose repair service but they don't supply these bizarre automotive sizes - in my case, these are M18 x 1.5 thread with the cone on the end of the male threaded fitting IYSWIM.

The threads on the coolers have been damaged during removal, and I'm not keen to re-use coolers that have previously had swarf pass through them, no matter how much they have been flushed, so with a pair of new genuine 220mm x 160mm coolers costing £800, I'm tempted to fit a pair of generic coolers instead.

Then I'll simply TIG a couple of AN-8 fittings at a convenient point on the OEM pipework, and run everything at using 'standard' hose fittings.

Unlike the original manifestation by ZF which had no monitoring or protection of the Transfer Box or Front Diff lubrication system, I shall also fit a couple of temperature monitors coupled to an Arduino with a small OLED display and a very large buzzer.

Uggers

2,180 posts

178 months

Friday 11th June
quotequote all
Audi by any chance?

9xxNick said:
A company such as Pirtek may be able to make you up some hoses to the correct spec if you take the old ones along. They also have a mobile service.
This is who the garage used when replacing my hydraulic lines when 3 of them needed replacing. £200 a go wasn't going to happen.

I don't see the need to go between metal/rubber/metal sections amd just keep it all hose from one end to the other. But ensure there is no risk of chafage, which is the source of a lot of failures.

Pirtek operate on a franchise basis, so maybe worth trying a few others who may go the extra mile for the business.
The 3 lines cost me £300 which included the labour for the garage so the cost saving is considerable. .



ColourRestorer

Original Poster:

34 posts

80 months

Friday 11th June
quotequote all
Uggers said:
Audi by any chance?
Same rubbish but in a posh frock: VW Bentley Continental GT W12

My blasting cabinet has been kept busy this week cleaning off all the brackets that have gone horribly rusty after being given just one coat of paint at the factory. Worse are the welded fabrications that had no post-weld cleaning prior to painting, hence have rusted at every weld.

All this in a 72,000 mile car that has always been garaged. But probably not cleaned after seeing salted roads.

Uggers said:
This is who the garage used when replacing my hydraulic lines when 3 of them needed replacing. £200 a go wasn't going to happen.

I don't see the need to go between metal/rubber/metal sections amd just keep it all hose from one end to the other. But ensure there is no risk of chafage, which is the source of a lot of failures.

Pirtek operate on a franchise basis, so maybe worth trying a few others who may go the extra mile for the business.
The 3 lines cost me £300 which included the labour for the garage so the cost saving is considerable. .
I hadn't realised that Pirek is a franchise, so I may well try them. Thanks

Uggers

2,180 posts

178 months

Friday 11th June
quotequote all
Sorry I should have added Pirtek is a franchise as far as I know.

But most hydraulic companies I know will be able to source the ends reqd. Failing that, reterminate your good bulkhead fittings/pipes with more commonly used fittings which enables standard type hoses to be fitted.

I'm sure there will be an affordable way around your issue. Good luck.

Arnie Cunningham

1,541 posts

220 months

Saturday 12th June
quotequote all
I used Torques UK on ebay for most of my hoses these days. They have a good choice of braided hoses - my current favourite is the black braided, stainless reinforced, teflon hose with black fittings. Have used it both on the RS (to replace OEM stuff) and the boat motor,

Easy to assemble at home, spec well in excess of what you need on an oil system and looks good on the car.

GreenV8S

28,860 posts

251 months

Saturday 12th June
quotequote all
ian332isport said:
Car manufacturers have an annoying habit of using non standard threads/fittings
There are plenty of standards to choose from, but I'd be surprised to see a modern manufacturer using a fitting that didn't comply with a recognised standard for thread, seat and so on. That's the thing you'd need to match when replacing.

ColourRestorer

Original Poster:

34 posts

80 months

Sunday 13th June
quotequote all
Arnie Cunningham said:
I used Torques UK on ebay for most of my hoses these days. They have a good choice of braided hoses - my current favourite is the black braided, stainless reinforced, teflon hose with black fittings. Have used it both on the RS (to replace OEM stuff) and the boat motor,

Easy to assemble at home, spec well in excess of what you need on an oil system and looks good on the car.
Many thanks for that suggestion. They certainly keep a wide stock, albeit no M18 x 1.5 conical seat fittings.
For anyone else looking in the future their eBay shop is here: https://www.ebay.co.uk/str/torquesuk

GreenV8S said:
ian332isport said:
Car manufacturers have an annoying habit of using non standard threads/fittings
There are plenty of standards to choose from, but I'd be surprised to see a modern manufacturer using a fitting that didn't comply with a recognised standard for thread, seat and so on. That's the thing you'd need to match when replacing.
Oh VW Bentley certainly use a recognised standard for the thread (M18 x 1.5) and the seat (conical 37º) it's just that they aren't from the same standard!

Edited by ColourRestorer on Sunday 13th June 07:24

Arnie Cunningham

1,541 posts

220 months

Sunday 13th June
quotequote all
Think Automotive will make you up any adaptor you want to get you into a standard JIC or whatever you choose size.
Merlin Motorsport at Castle Combe are also excellent.

Otherwise I can see lots of M18 adaptors that would probably be a good base to tweak in the lathe, if you have one.