pulling apart carbs...

whatnow Custom Title Time!

1,000 posts · joined Jan 2003 · 12 Oct 2006, 12:09 am

#543409

hi i'm pulling apart a set of Solex P40II twin throat carbs (or P11-40's as i think they should be called), and have hit a snag with the chokes... ie i can't get them to budge.

i've got the retaining screws out and the bit that goes in above them (no idea what it's called) and run WD40 around the top joint to help lube things but the chokes won't move.

the carbs had sat for a while before i got them and had a little of that white powder in the bottom of the float chambers and passages but it's not bad (ie bad enough to jam the chokes in solid)

i was considering pooring bouling water over the body to try and expand the body just that little bit. worth a try? is there a special tool to get them out?

also i'd like to pull the shafts out so i can clean all the bits properly, re black the shafts and fiddle with the shaft joints (they are the split shaft version). are the butterfly plate screws locktighted in? peened in? just annoying? any suggestions on how to get them loose? someone in the past has tried to get the screws out and rounded out the slots, i don't want to worsen the situation.

thanks.

henry.

ctefeh Wolfsburg Wizard

479 posts · joined Apr 2005 · 12 Oct 2006, 9:49 am

#543456

Whatnow,
Most screws holding plates onto shafts in carbies are peened. I've done a few different brands over the years and it's fairly common. Just look at the bottom of the screw where it exits the shaft.

To undo them, I file or dremel (really carefully) the bottom to remove the peening. Then undo them like tapping a thread, ie 1/4 turn out, back in, 1/2 turn out, back in etc. I try and save the screws simply because you may not be able to get replacements. Putting them back I use Loctite and centre punch the screw bottom.

If they have been loctite'd, judicious use of heat may be in order. Use some soap on the aluminium to let you know when the carb is getting too hot.

The P40's are sidedraft? You may be able to find an exploded diagram on some sites in the US. From faulty memory I think Mikuni rebadged these?

Ctefeh

Bizarre Moderator The artist formerly known as blue74l

12,785 posts · joined Aug 2002 · 12 Oct 2006, 12:47 pm

#543502

ctefeh wrote:The P40's are sidedraft? You may be able to find an exploded diagram on some sites in the US. From faulty memory I think Mikuni rebadged these?

Ctefeh

P 11 40's are down draught.
Sort of like IDFs.

Yes - i believe there is a venturi remover

Futue te ipsum!!!

whatnow Custom Title Time!

1,000 posts · joined Jan 2003 · 12 Oct 2006, 1:29 pm

#543519

thanks for the info.

40 P 11s are downdrafts off 356SC and 912 motors (the -4's) or fiats? (the -6's which i have)

i checked the screws, they are peened. i'll give the dremel a go.

how does the soap trick work?

henry.

edit here's a link to some -6's http://forums.aussieveedubbers.com/viewtopic.php?tid=56242&page=1#pid532387
the ones i'm working on are the bottom pair.

[ Edited on 12-10-2006 by whatnow ]

ctefeh Wolfsburg Wizard

479 posts · joined Apr 2005 · 12 Oct 2006, 2:48 pm

#543535

Whatnow,
Soap (like Sunlight yellow) will turn black at a temp lower than the melting point of aluminium.

So if your soap turns black on your aluminium while applying heat to whatever bit, time to let it cool!

Ctefeh

whatnow Custom Title Time!

1,000 posts · joined Jan 2003 · 12 Oct 2006, 3:34 pm

#543541

thanks ctefeh thats a great tip, it could save me lots of tears.