Coolant Hoses

[CtrMint]

Guys,

I need more help.  I've been having a dialogue with Derek @CC over coolant/heater hoses, and to be honest not really happy with the outcome.  Thought I'd bounce it off here.

The crux of the matter is that Derek has instructed to me to use a straight hose from the the heater valve to the submarine and not the 90 deg L shaped hose which I only have 1 of.

Derek's response,

Hello Mark,

We do not use an L shape hose to the heater just a straight hose that bends from the submarine to the heater.

Kind regards

To me this seems a terrible solution as the hose will curve horribly, especially in comparison to a 90 degree elbow which would be far more appropriate.

I dont want to cut the hoses and then find its a terrible setup and I have unusable off cuts.

Thanks

[Jim 123]

I think you will find a description in the 2015 Manual where the L hoses fit and their purpose is described. Without seeing the question you asked Derek, he is correct that it is a straight piece of hose that spans from the Sub to the heater.

[Jim 123]

If you zoom into the photo on page 127 of the older Manual you will see the hose you should be working with along with the submarine fitted.

[CtrMint]

That image looks like a far sharper curve than I can achieve with a straight section.  I've tested fitted, and I'm even more convinced now.

90 degree bend -- good fit.

Straight hose with large radius curve.

Of course I need the 90 for the expansion back to the T.

[CageyH]

I made my own up with Samco silicon hoses.

[CtrMint]

Checking the Caterham parts website also confirms the 90 deg hose should be used for the heater and T.   This is crazy.....

https://caterhamparts.co.uk/hoses/2832-hose-t-piece-to-heater-sigma-r400.html

[John Vine]

The 2015 AG says:

Heater hose is supplied as three pre-formed pieces; a short ‘L’ shape, a long ‘L’ shape and a long ‘J’ shape:

The short ‘L’ connects the ‘T’ piece to the engine inlet next to the bottom radiator hose.

The long ‘L’ shape must be cut in two to provide a long straight hose (to connect the ‘T’ piece to the heater outlet) and a short ‘L’ shape (to connect the expansion tank to the ‘T’ piece). Measure the relevant distances carefully before cutting the hose.

Before fitting any hoses remove the bungs from the ends of the heater pipes.

The long ‘J’ hose connects the heater inlet to the water outlet at the rear of the cylinder head (next to the top hose ‘U’ bend). This hose must be trimmed to length. Cut a 240 mm length of hose from the straight leg and cut this into two 120 mm pieces. Use the 120 mm pieces to connect the heater inlet and outlet to the heater valve.

I suspect the long L-hose you linked to in post #6 is in fact the third one listed above?  If so, it has two jobs: exp tank to T (90deg bend) and T to heater (straight).

JV

[Jim 123]

Mark, I think this is a toss of a coin.  The curved version in #4 is pretty typical of what you will see under the hood in most Sevens after the Sub. What configuration of hose do you intend to make from the engine into the Sub?

[CtrMint]

Thanks I've gone with the solution which I feel is the better solution, regardless of the cryptic manual.   I've used the 90 between the heater and submarine, the off cut between the heater and T.  Much tidier.

That leaves me with 2 J hoses, which I'm convinced is incorrect, regardless I only need to sort the bend from the expansion to the T.  I could hack the spare J hose to fit, but the bore is massive even though it reduces, won't be a great seal.  I'll focus on solving that as the problem rather than deciding on the bend by the submarine.

The other J is clearly the inlet next to the submarine.

 

[CtrMint]

Having a look on the parts site, 

https://caterhamparts.co.uk/hoses/2849-hose-header-tank-to-engine-a-heater-feed-sigma.html

So this appears to be the expansion tank to engine and also the heater feed.  We know its defo the heater, and header tank sounds like what I refer to as the expansion bottle.

I'm wondering if I have accidentally done the correct thing, I'm just expecting a better fit?????  I basically have 2 of these, one J for the header and the other for heater.

[Jim 123]

The part in #10 looks like a small bore hose that fits to the top spigot on the expansion bottle.