Paging Lozzo and them wot knows carbs...

I popped in to SpeedySpic Engineering this afternoon, because I was
struggling with the carbs on the 'Wing. They're supposed (according to
the BoL) to pull 21mm of vacuum +/- 2.5, and they weren't even close.

After some pissing about, the consensus was that there was probably a
split diaphragm. A good theory, but with one essential flaw...

These carbs don't have diaphragms[1]. They've got these cute little
pistons that go up and down instead.

Now, there's a *lot* of shit kicking around inside there, so that may
not be helping, but the pistons move quite freely.

On the float bowl with the main fuel pipe leading into it there's a
little rubber diaphragm (about 1" across) which is pushed down by a rod
which is hit by the throttle arm on opening. Some kind of crude
accelerator pump? The BoL has no sign of it, of course. That was full of
crud and the rod had rust on it. I've cleaned that up.

The gaskets that seal the inlet manifolds to the cylinders look pretty
shot too. They'll get replaced.

Before I put all this back together, anyone got any other suggestions as
to why an even tickover is hard to get, they pull very little vacuum at
tickover, and the pick up is 'woolly'?

[1] Which is nice, 'cos "diaphragms" is a **** of a word to type...

 

Do the revs take a while to settle again after you blip the throttle?
If so it *might* be a leak at the intake.

I hate carbs with a passion. Fucking fiddly things when they go wrong.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique,
typed

What is this "settle" of which you speak? It's a definite possibility,
especially given the state of the inlet gaskets.

Yep. Second behind electrical shit in my book.

 

You know, drop back to 1k or whatever it's meant to tick over at.

Hmm, electrical isn't as bad as carbs afaic.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique,
typed

Heh. Yeah, I knew that. I was kind of trying to subtly make clear that
an even tickover is not currently on the menu. ;^)

 

Nigel Eaton let forth with a mighty belch and uttered :

<snip lots>

they pull very little vacuum at

Do these carbs have oil dampers a la SU carbs?, if they have, and they are
dry of oil, it may affect it. The dampers are really to stop the piston
rising too fast when you crack open the throttle. The prescence of what
appears to be a crude accelerator pump may mean they haven't. Another
funtion of them is to smooth out fluctuations at idle or low throttle
openings. On multi-SU carbed engines, you can tell when one carb is low on
oil as you can't balance the buggers[1]

Probably utterly wrong, but easy enough to check.

[1]Yes, I learned the joys of SU on Minis.

 

For your delectation...

http://www.newcovenant.com/features/motors/GLtuning.html
--
| ___ Salad Dodger
|/ \ GL1500SEV/CBR1100XXX/KH500A8/TS250C/exTS185C
_/_____\_ ..61132../..13991.../..3157./.19406/.fecked.
|_\_____/_| IMC#4 TPPFATUICG#7 YTC#4 DIAABTCOD#9 PM#5
(>|_|_|<) BOTAFOT #70 two#11 Ignoramus #0001
|__|_|__| BOTAFOF #09 IbW#0 & KotIbW# OSOS#07
\ |^| / WG* BotTOS #6 GP#4 ANORAK#17 FTB#14
\|^|/ 2003 RBR landmarks:99 points:2100 miles:8000
'^'

 

The description of the metal piston carbs leads me to assume they are
similar to what's on my '81 CM400T and was on my ex '81 CB900C. There is
another possible vacuum related rubber bit on these carbs, called the
air cutoff valve, it's behind a little round plate on the side of each
carb, secured with three screws. I'm not quite sure how they work but
if those diaphragms are perished, I am sure the carbs won't work as
designed.

I'd also make sure the inlet rubbers that go between the carbs and the
cylinder head are up to snuff. Some Hondas of that era use inlet
rubbers with a metal flange toward the cylinder head that used an O-ring
to seal against the cylinder head. That O-ring can harden up over
time due to heat, and should probably be replaced if you have that type.

The carbs are somewhat reminiscient of the SUs I had on my MGBs, but
they do *not* have an oil damper.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Salad Dodger

I am obliged to the Honourable National Treasure.

 

I always have trouble with "netwrok". "Enjoyment" is a cracker, though.

 

I *thought* you might but the questionmark made me wonder... Feeling
remarkably lacking in humour tonight.

Bought a load of kit from a computer fair to build a new PC (nothing
flash, athalon XP2200). Got it all home, put motherboard, processor and
memory into case (bought from same shop) connected a monitor... and...
nothing just some beeps.

Took it back... "sorry we can't look at it today". "Well I'd like a
refund then". Spent the next 30 minutes pulling it apart and
substituting bits. Eventually they concluded it was the processor that
was fucked. They didn't have one of these so leant me a Duron 1400 for
two weeks (bought from a computer fair) and said they'd swap the
processors in two weeks; and put this in writing on a receipt. Fair
enough.

So then went home and built it up. Much cocking about later and the
audio/lan won't work. Drivers don't appear to be present for Windows
98. A little websurfing and.... it transpires that the motherboard
Nvidia chipset bits don't have drivers for Windows 98 only 2000 or
later.

*sigh* that's a copy of XP I'll need to order then.

 

Blocked pilot jets or incorrect pilot jet settings.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Nigel Eaton

Bad form, ya-da ya-da...

A call to David Silver reveals that they're (probably) carbs from an
early 1100. I'm hoping this isn't going to turn into a major problem...

Anyway, carb rebuild kits and new gaskets on their way.

 

I have a man(1) sitting next to me who Knows These Things. He says he
knows a man who knows early Wings - and their carb problems. Bottom
line - the crbs are fucked. The internal passageways and ports are
furred up and you cannot get at them to clean them out.

New carbs is the only way out of this, mate. Do it now, do not
hesitate as they are in pretty short supply and getting shorter.

Argh.

1. Col. Tupperware of this parish - 'e knows 'is 'ondas.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Pip

Oh arse. And further arse. With a side helping of arse.

Well, the kits are on order. I might as well at least try...

Hah don' lahk heem no more.

 

No

 

Har well fark yu and the hoss you rod in on Gringo.

I was thinking, that maybe the only way to clean 'em out would be to
try an ultrasonic bath. There was one up on ebay the other day for
about 70 of your earth sponduliks.
My expert, (yes he really is an expert) on older Wings told me about
this problem when I asked him for some advice on a bad running wing.
HE say it is well known amongst the Wing fraternity that GL1000 and
GL1100 carbs will furr up when they haven't been used for a while and
it writes them off.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, ColonelTupperware
<> typed

(Of 'Wing carbs)

Ooh! A chance to spend money. Thank you.

That's a bugger. As I said I'll have to at least try. Matey said that he
had been starting the thing fairly regularly, so maybe there's hope.

Thanks for the advice.

 

An incorrect float height and or has been compensated for by over
adjusting the low speed air screw would give this effect (if it has an
air screw). Check the float heights with a vernier gauge.

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, Mick Whittingham

I shall do that.

I have just spilt beer all over the V5 for the GoldWing.

That seems curiously appropriate, somehow.