Change fuel hoses?

[thor]

Hmm.. The PO of my Elan was an engineer, and had the car for 26 years. Everything is rock solid and well put together in the car. But I have my doubts about the strange fuel hoses between the pump and first Dell'orto, and between the carbs. I've never seen this sort before, it almost seems heat-shrink fitted, and with NO hose clips! Are they brilliant, or should I change them? Also, the hose coming through he firewall to the pump is a clear hose, doesn't look to have a hose clip either...Should I worry? And where to fit an auxiliary filter, right before the pump?
have a look here (in the photo gallery):

http://www.lotuselan.net/gallery/displa ... at=0&pos=0

[elan_fan]

I would say that it is perfectly ok. I suspect that it is a genuine Lotus "fuel loom" as they have been using a modern nylon type of pipe for quite sometime. The fuel hose between pump and T piece on my stromberg Elan has exactly the same type of material and that is a genuine Lotus part. If you have the original type of pipe running from the tank to the pump it is the same nylon type of pipe.

regards
Mark

[types26/36]

I agree with Mark, looks like the original Lotus fuel line to me. My Europa (since sold) had exactly the same fuel line and this was the original fitment. The only thing that would worry me is, is it still in good condition after 30+ years?
Brian.

[cliveyboy]

Because the pressures involved are very small you can use a simple push on connection.
You just need to keep an eye on where the pipe pushes over the end fittings as it is stretched and will fail there first. also being plastic type pipe it does go brittle and perish over time so another reason to check regularly.

Cliveyboy

[thor]

aha, ok. As the engine has been rebuilt twice, and the maintenance otheriwise is in top order, I recon this has been changed more than once. The only thing worrying me is the clear hose to the pump (coming thorugh the firewall). Seems to be sweating a bit by the connection to the pump...

There's no auxiliary petrol filter, is it OK with the normal type plastic one, and where to fit it, between firewall and pump? Or after?

[types26/36]

[quote="thor" The only thing worrying me is the clear hose to the pump (coming thorugh the firewall).
There's no auxiliary petrol filter, is it OK with the normal type plastic one, and where to fit it, between firewall and pump? Or after?[/quote]

I'm not all that clued up on the plus two's but does the fuel hose come through the firewall ??? doesn't it run from the pump through the chassis backbone? ....I seemed to ,remember Lotus used a black plastic hose and not a clear one and if this is the case then it has been changed.
If you are useing the Lotus mechanical pump it has a filter inside (although difficult to get at) I know the fuel tank on a plus two is not as accessible as the small Elan but wouldn't it be easier to fit an inline filter at the rear in the outlet pipe from the tank?
Brian

[thor]

Good point, I'll have a look in the boot!
it might well be coming through the chassis, I haven't taken the airbox or carbs off, this was purely an observation based on me peering down into the dark of the engine bay without a lamp...

[rgh0]

Thor

The clear nylon hose should have a ferrule and nut compression fitting where it goes into the pump. If its sweating I would dismantle the connection, ensure the ferrule is fitted correctly on the nylon hose and reassemble.

If I was retaining the standard mechanical pump and wanted to fit a proper filter into the system in additional to the mesh screens in the pump and in the carbs inlets I would locate the filter in the hose after the pump. I would replace the black plastic hoses with new rubber hoses and proper worm drive clamps and fit the filter in lthis new rubber line below the carbs.

Rohan

[thor]

Thanks Rohan, This was my thought too. Xcuse my ignorance, but what is a nut and ferrule connection..?

[rgh0]

The ferrule is a small piece of soft metal ( usually brass of some sort) that is close to circular in shape with a hole bored through it. It is slipped over the hose. The nut is fitted to the hose first and then screws into the pump female thread compressing the ferrule onto the hole to seal it and also compressing the ferrule against the pump body to seal there. The same type of system is used for the nylon pressure hoses in mechanical oil pressure gauges and lots of other compression style fittings using both metal and plastic tubing.

Other terms I have seen used is "nut and olive" or just "compression fitting" in Australia maybe other terms elsewhere.

regards
Rohan