FV/FVP Carb Body.

[Gannet]

The 1/8 BSP threads where the banjo bolt fits have been stripped. (Not my fault!).
I am looking for a replacement carb body or indeed a complet carb.
This carb has a 7/16" venturi bore. It is off an FV and I assume the FVP is the same. It is possible that the LM/LS also have the same carb.
I believe (not at all certain) that all SJM/SJP had a 1/2" bore, so that these are not suitable.
The other choice is to helicoil it. Does anybody have a kit that I could use?
Thanks.
Jeremy

[1650bullet]

Yes all 40series have a different venturi size to the Square cyl block 102 series motors. I have tried a 102 Villiers carb on a 40 plus once and it was no good. It just over fuelled all the time. You could ask john from SOS and see if he has any lying around. You only need the carb body only, so it would be cost effective to go that way instead of coiling it.

[Oyster 49]

Jeremy,

I have the kit to fit a helicoil 1/8 BSF. I can loan you the tools, or you can send me the carb, and I'll repair it for you.

[Gannet]

Thanks,

I will give you a call.
Regards
Jereny

[JERSEYMAN]

Hang on, I may be wrong but I always thought the villiers carbs on the 40's and the Century's were the same,
running on the same jetting

[1650bullet]

Unless someone beats me to it, I will take a couple of pics of a 40 and 100 series Villiers carb and show you the difference in venturi sizes.

[Gannet]

This wanted post was initially about a replacement/repair to an FV carb.

It is not correct to say that all 40 series carbs are the same. For example the FV carb has a 7/16 venturi and some if not all SJMs had a 1/2" as well as other detail differences.
So a general overal statement between 40, 100 and century carbs is not going to be accurate. Additionally I would expect that there would be other differences, but I really do not know.
Jeremy

[1650bullet]

Sorry it took a while but these are the best 2 pics i could could take to show you the difference in size between a 40 series and century villiers carb, It works out roughly just under 13mm for the century LLs series venturi. and 11.20mm for the 40 series carb venturi.

[Collector Inspector]

That is interesting

B

[Keith.P]

Wouldn't that be because the 40 series is 64cc 11.20mm carb and the LLS is 102cc 13mm carb and higher HP.
Like the FVP/FV have restricted carbs as they are 64cc like the 40 series, but less HP than the standard 40.

[1650bullet]

Wouldn't that be because the 40 series is 64cc 11.20mm carb and the LLS is 102cc 13mm carb and higher HP.
Like the FVP/FV have restricted carbs as they are 64cc like the 40 series, but less HP than the standard 40.

That would be wright Kieth. I was always under the impression both 40 and 100 series villiers carbs were all the same and interchangable until i was having majer dramas with my 40-plus. I then researched this website and found out that they are different, not only in throat size, but the main jets to. Thats why i had to get Taspiper to repair the air intake thread for me because it was the only 40 series venturi i had. Using a 100 series villiers carb on a 40 series engine is like leaving the choke on.

[Charles uk]

I think you will find there are 3 different Villers carb sizes & the FV & the FV are not 64cc but only 58cc, Jeremy if you get the chance could you measure the bore & stroke on your F, FV, FVP & your LS if you've got one, so as to clear up some of this confusion.

[Gannet]

Charles,
I only have Fs, FVs and SJM.
I have measured:-
The stroke on FV1867T to be 1.372". The drive shaft and gearbox were connected, so I found it difficult to determine TDC and BDC.
The stroke on FV2682 to be 1.375. The drive shaft was not fitted, so this is a more accurate figure.
Note;- These dimensions were obtained by measuring the position of the piston crown ie not directly on the crankshaft journal.

Just to add a bit of confusion I have measured the piston from FV2682 and found the skirt diameter to be 1.768. I am not going to guess the clearance, so I do not know the bore diameter. However using 1.768 and a stroke of 1.375 my calculation give a swept volume of 55.32cubic cm ie the actual correct volume cannot be less than this figure. Isn't this helpfull!!

I must make a determined search for my bore mic. and then I can produce a useful figure.

Jeremy

[Gannet]

Charles,

Just found my bore mic.
Measuring the worn, scored and corroded cylinder block ex FV2682 produced a diameter of 1.771.
With a stroke of 1.375, this gives a swept volume of 3.3871 cubic ins which equals 55.50 cubic cm.
Jeremy