S2 Fuel Breather System for restoration of 837G. - confused.com!

[Alistair Enser]

Hi all,

Hopefully someone can help. Having looked in my manual ( which seems to only have a diagram of the US set up with charcoal canister) I am trying to figure out how to connect my fuel fillers , tanks and breather system on a late S2 2.0

I have the straight style filler hose ( not the curved one). My tanks have one connector on top , so it is clear that large bore pipe on the tank connects to the filler neck using the big bore straight fuel pipe.

However, on each filler neck there are two other pipe connections, one which is approx 14mm diameter and one which is about 6mm.

I’ve scoured the internet and forums, but failed to find a diagram/ description for these? I’m assuming at least one of them ( the bigger?) is the connected ‘side to side’ over the rear window under the carpet trim.  If so, what is the thin pipe connector for ? Overflow?

can anyone help please _ thanks 

 

[TAR]

I think you may have the wrong fuel tanks. According to the parts manual all S2 cars had tanks with filler vent pipes. This means you should have a 2nd outlet on the tank which connects to the filler neck.

Alternatively you could have the wrong filler necks? The early S1 had straight necks with a curved hose.

You probably have the early S1 tanks with just the filler neck connection?  

[Alistair Enser]

Mmmm 

 

Thanks Tim,

 

If course where Lotus and previous owners are concerned - anything is possible .Let me check .

The body, chassis, engine and tanks were all together when I got the car and judging from the state of chassis bolts and engine had never been apart ( at least not since 1990 when it was last in the road). Everything I have found is original , so it would be very odd if the tanks had been changed . It even had the original intact foam from the factory with the chassis number written in pen on it - when I split . 

All parts were all well fitted and rusted into the car which had been off the road since 1990 and I doubt from the state of the chassis bolts and engine they they had ever been removed - at least certainly not in the last 30 years, which begs the question why would they be removed changed so early on.

Unfortunately when I removed it all it was the one part I did not prolifically photograph . I just thought - pipes - easy .

The filler hoses were connected and were straight . I cut them off and replaced with new .

The old and very yellow looking pipe which went across the car was mostly intact so I assume I replace that 'as is' joining the tanks ?

As for the skinny unknown outlet on the filler neck  these had a short piece of black rubber tubing on them but I have no idea where it went or what it connected to . I don't recall disconnecting it from anything .

Mine is a very very late S2 . Is it possible that it is a parts bin 'run out' car with some S3 parts, some earlier parts ? For example, the mirrors look exactly like all esprit ones but the glass is very slightly more square. Also LotusBits had to make a rare but not special  alloy water pump pipe pipe which had an extra outlet hose on it ( maybe different as it is an Aircon car)

Thanks 

Ali

 

 

[Alistair Enser]

Any diagrams of the S1 and S2 setup ( European not federal ) would be a good starting help 

 

Thanks All

[TAR]

I'm not sure you'll find a diagram for the later S2 cars. The official Lotus parts list shows the original early S1 parts. see espritengineering.co.uk/wp-content/uploads/2018/11/Service_parts_list_Esprit_S1_S2_S2.2.pdf

Have a look at this for the S3 as it shoes the tanks with the extra breather - Service_parts_list_Esprit_S3_81-87.pdf (espritengineering.co.uk)

Hope this helps  

The smallest pipes on your fillers are for the fuel vent pipes which run over the top of the engine bay  

[Alistair Enser]

Thanks Tim 

So if the early S1 only had one pipe on the tanks and the thin pipe on the filler is for the neck , do the early S1 have a second pipe on the filler or was this just introduced for the S2?  Ie could the car have the second pipe capped off? 

Also do the 'thin' vent pipes literally just join together or are there any valves 

Thanks 

Ali

I had seen that diagram you sent the link for , but it is also for a federal car as it has the vapour catch tank and charcoal cannister which UK cars didn't have . Seems like as you say diagrams are difficult to find 

[drdoom]

Re the lesser pipe connections I believe it would the 14mm for side-side breathing, as you've surmised, and the wee one for overfill spillage. My Federal S2 does have a charcoal canister but no valves that I can recall. Breather connections were in transparent PVC tubing, not at all suitable for modern fuel blends. Will have a peek at my filler necks in a couple hours hence.

Cheers

[Alistair Enser]

Thanks Steve 

Any help or additional information from you, Tim and anyone else will help the mystery 

 

Ali

[drdoom]

Got a look at one of the filler necks late yesterday and it appears the same as what Alistair has, one larger and one lesser hose connection for breather/overflow. The attached photo shows tubing associated with breather tank ( believed to be out of sight above ) and the charcoal canister seen clamped over the wheelarch. Note the surgical rubber hose used for the smaller lines, utterly questionable in terms of durability yet still quite intact after 20 years in service.

[Alistair Enser]

Perfect .That's very helpful 

So the million dollar question -.any idea where the thin breather hose 'exits/vents to' and does it have any filter / valve on it .

Interestingly both my wheel arches in the vicinity of the tubing have a small '5mm'.hole in them . I don't know what for and wondered if it was to do with breather/vent  . Then again I wouldn't think it a good idea to vent vapour or overflow fuel onto a rear tyre! Not unless it is for skid pan training 🤣

 

 

[TAR]

The parts diagram for the S1, S2 & S2.2 list 2 non-return valves A076L6001F with a description of 'in filler breather pipe'

These aren't shown on the diagram.

I'm sorry that I don't know the exact path taken by the breather pipes.  

[Alistair Enser]

Thanks all.

For the time being I have ordered two 'roll over ' vent breather valves - one for each side .