Solex Carbs

[pls01]

I noticed on the Aceca Bristol BE603 that there are no accelerator pumps on the Solex carbs.  Instead there are just blanking plates where the pumps would normally be situated.  I noticed this on a few other Bristol engines.
   
   Does anyone have comments on this set-up?

[Jim A]

I pumped the gas pedal on my Ace Bristol (100D557) to prime for starting for almost 30 years.  Then I rebuilt the carbs and was somewhat embarassed.
   Haven't told that story alot.

[pjbowman]

I believe the engine setup in 603 is not original. For one thing, it's a B2 spec engine, and Mills only lists one car (1 1956) with a B2 setup. Plus the papers in the listing list a different engine, so the ID plate looks to be a repro stamped to match the current numbers. Others can correct me, but the AC Bristol version of the engine had the accelerator pups on the carbs. Setups in cars like the Arnolt Bristol did not. Upgrading to carbs with the pumps is/was a popular mod to the Arnolts. Wouldn't be surprised if the engine setup came from a Bristol 404.
   
   Peter B.

[Jim A]

My memory may well be faulty.  It has been 20 years since the rebuilds I mentioned and nearly that since the car was destroyed.
   I remember being very surprised in dismantling the stock Solexes that there was not the accelerator pump mechanism that I had seen in the many other carbs I had worked on.
   Peering down the throat of a carb while working the accelerator and looking for the tell-tale little squirt has always been the best way to see if you are out of gas.
   So the ultimate test here is for a poll.  Who has the little pulse of fuel?

[AC Ace Bristol]

Peter  /  Jim
   
   The accelerator pump you refer to is infact:-
   
   Part Throttle Enriching Device
   
   Engines of varying characteristics occasionally require during part throttle operation a tempoarily assisted main jet output to ensure immediate and affective acceleration.
   
   This is achieved by the Part Throttle Enriching Device which consists primarily of a petrol chamber in direct communication with the float chamber by means of a filter plug,also a spring loaded cut off and a membrane assembly.
   
   So when you hit the accelerator and the carbs take a big gulp of air this device will squirt in extra fuel,otherwise you would experience lack of power due to too weak a mixture.
   
   For further details please refer to the "Solex Literature" I had  Bryan put on the Ace & Aceca Model section a few years ago.  Exploded diagramms, fault finding and setting up ..  .. download a copy and keep it in the workshop.
   
   AC and Bristol developed the Bristol engine, Therefor all 100D2s were fitted with this device. maybe 2.2 Bristol engines also benefitted with this device.
   
   Hopefully this puts ones mind at rest and explains why some Aces and Acecas are fitted with Solex's with "Part Throttle Enriching Device" and some are not.
   
   Keith  [:)]

[Jim A]

Keith:  May I have better directions to "Solex Literature?"  Unless it is in the members section, I can't seem to locate it.
   Jim

[AC Ace Bristol]

Jim
   
   When you enter ACOC  web site,  go over to the right.  type in the Username & Password in lower case and login. Refer to current issue of ACtion for confirmation of username & password.
   
   Click on Model Directory
   Select model.......Ace
   Click on Articles
   Scroll down to last article....  Solex Carburettors.
   
   Good Luck.......  If you have a problem, please feel free to email me and I will scan and email you a  copy.
   
   Keith

[Jim A]

OK.  That, especially the drawings, is pretty definitve.  I can't think of another instance when my memory has failed so completely.
   At least I remember what color it was (I think).
   I would be interested in hearing about any 100D without accelerator pumps.

[AC Ace Bristol]

Jim
   
   As the Bristol engine was developed through the 85 series then the 100D & D2 and beyond, carburreration was also scrutinised and developed,  I believe all 100D2 engines were fitted with the Enrichment Device, not sure if all the 100D series were.[?] [?]
   
   Some cars during there history, especially if used competitively were upgraded, Others lost their original engine's and something suitable was fitted to keep the bugger on the road or track.
   Its all part of the colourful history of our ACs, Does it really matter if the carbs had or didn't have the enrichment device ?? Some racing Bristols running on methonal at 13:1 did away with the enrichment device altogether, Where others thought it the best thing since sliced bread.
   
   Just keep using your Ace, drive as if you Stole It ...  Enjoy!!
   
   Lifes just too short.....[;)]
   
   Keith  [:)]

[Brian Horwood]

Can anybody help? I have searched through all of the instruction books and leaflets but cannot find any mention of the design or prefered fuel (or float) level for the Solex 32 B2.
   When I switch off the engine a small quantity of fuel overflows onto the butterfly in carb 1 and ultimately through the spindle bearing, making a mess and a strong smell of fuel as it evaporates.
   I have fitted new needle valves using both fibre washers.
   
   Brian