New to me mk1 Camel in OZ.

[rossguzzi]

Fine tuning continues.
Went on a small group ride today on single track/forest. Bike went well but I have discovered something. Getting there was a 30 minute ride on the highway and up a gradual incline in 5th. I pulled up to refuel and noticed fuel on the outside of the left carb. I suspect it is coming from what looks like a plug on the side of the carb. I wonder if this is contributing to the stumble off idle and I often get some popping on decel. I have gone down from 52 pilot jet to 42. It`s the only time I have seen fuel in that area. Could it be leaking there and sucking air on decel ?
Otherwise it was a great ride. There was some knarly stuff and it handled it ok.

[Ming]

Camel beats the pants of all that modern stuff. The only plugged orifices I can think of on the carb would be the one used for the balance pipe, which if not connected to the other carb should be blanked off. As it's on the engine side of the carb, I wouldn't expect much petrol there.

[rossguzzi]

Here is a pic of the carb where the fuel was coming out. At least I think it was fuel. Smelt like it. Just above the idle speed screw there is like a key hole shape. Just under the tip of the choke lever. If you look close it is fresh alloy in colour. all else around it is slightly stained. Anyone know what this is ? looks like it was a machined gallery plugged. Perhaps the plug is leaking ? I really am guessing.

Suspension.
Well actually I think I may leave it alone. If anything I may refresh the front with 5 wt one day. But it is not bad when on the trails.

Starting.
At the moment it dosn`t need any choke. It`s winter too. Need to go down a size or two on the pilot jet again. Just looked up specs on the Dutch site and it says the 500 Camel should have a 45 pilot jet. It had 52 and now 42. Still needs to go lower IMHO. But it starts reliably when hot and idles ok. A little black smoke after idling for 30 seconds to a minute and blipping the throttle.

At a fuel stop on that ride 2 guys walked over to admire it. One was on a new Victory cruiser the other on a Hardly. It sure gets attention.

Loving it.

[MickeyMoto]

Could it be an overflow to stop the engine flooding if the float needle becomes stuck open?

[Haboola72]

Yes, some kind of breather /overflow. On the 501 Camel theres a keyhole casting with a 3mm pipe in the middle on either side of the carb. Two green rubber pipes are routed above the carb and vented to air on the chassis cross tube (4 in all for both carbs) It all looks a bit Heath Robinson but aaranged that way to discourage muck clogging things up I suspect ?

[rossguzzi]

Good info, thanks. Dont quite understand why it was forming fluid around it on a up hill run. Perhaps it was condensation ? Didnt think it was that cold.

[morini_tom]

It’s the vent above the float chamber.

Check your float heights, and if they look ok check the floats themselves as they can split and take on fuel. Can be hard to spot a split float, even the white ones so best way is to remove the float, pin it down under water for a good while and then check if it’s taken on water afterwards.

[rossguzzi]

Thanks Tom. That makes sense. I have before checked float hight, but didn't check for leaks. Will report back.

[mbmm350s]

Hi
I think fuel has been leaking from the open overflow/vent for some time judging by the yellow varnish on the carburettor - though that could be sand!
If your camel has the PHBH26HS carbs with the brown solid floats that are marked 14g then
I would test by floating in petrol and checking the weight before and after with accurate scales.
These floats as Tom says can absorb fuel, but not as badly or as obviously as the white floats which are hollow.
I have also seen several grams of gunge stuck to floats before! Also varnish can be present inside the float pin tube,
and it gets sticky and stops the floats from operating correctly.

A little black smoke after idling for 30 seconds to a minute and blipping the throttle

A sure sign of fuel seeping past the float valve and/or too high a float level.

The float height is set according to the Dell'Orto manual its nominally 24 +/- 0.5mm but for Morini i would
tend towards the lower end i.e 24.5mm. If the problem persists then i would consider replacing the needles in the float valves.
Actually even replacing valve seats and needles with viton tips as a pair as they are supplied in the UK. The needles are expected to rotate in service
if you hold the carburettor and operate the float lightly in partially closed to closed operation does the needle rotate if not it might be sticking.
Each corner of the needle is chamfered but not so worn that it can jam at an angle.

Improvement in fuel economy by prevention of leaks and not running rich will surely pay back the cost of the valves and seats.

Mark

[mbmm350s]

Hi
just looked at some phbh26bs carbs off a 500
there are two overflow vents one either side of the carb.
they look like they are plugged but they are not!
Also these have 11.3g solid brown floats.
Anyone know the correct float for the Camels?
Mark

[rossguzzi]

Mine are the brown (not white). Not sure what gram it is.
Another possible cause of the stutter I have thought, could be worn a slide, worn needle. Stock pilot jet apparently should be 45. Mine is 42. I may try 40. But I'm thinking it is in the floats or slide/needle.
Looked at the front carb float this morning and they look clean and move freely . Also the float seat and needle has been renewed with the Viton ones.
Another thing I have noticed is it starts without choke. But if I use the choke on the front cylinder it runs at a higher rpm but also has backfiring. If I use the choke on the rear cylinder, it runs higher but no backfiring. I am sure the stutter and backfire are connected. Also changing down with high rpm overrun has popping on decel. If it is a gentle change down (lower revs) there is no popping.

[mbmm350s]

Hi Ross

Also the float seat and needle was renewed with the Viton ones.

Did you reset/check the float height?
recent supply of viton tip and seats assembly that I had came with a much thinner fibre washer than original supply.
This caused the whole seat assembly to be higher, thus raising the float level.

your symptoms to me feel more like high float level or fuel seeping past the valve, than too large a pilot.
I would get the float height spot on first. then you can tune the pilot jet.
Air box connections and air box look stock to me.
Hopefully someone will have the Camel float weights to hand

Any thought of leakage past the valve would need a pressure test to check.
man how we used to blow down the petrol tubes with float valve lightly closed years ago - shudder at the thought now .
My father used syphon fuel with his mouth and he will be 90 this year! He had health and practised very little safety
Mark

[rossguzzi]

Float weights here. http://www.motomoriniclub.nl/carb.html
I am sure i changed the seats etc and then checked the float hight. But I may check them again. 9.5 gm is what the table suggests. I will have to find a way to weigh them.
All the airbox is stock, except someone (I think) has drilled holes in the bottom of the airbox. I guess this was to improve airflow.
Thanks for all the advise

[mbmm350s]

According to my 1981 dell orto parts book

500 camel 1981
Part no. 1.39.2.464
Spillo conico (needle) X8 notch 3
polverizzatore emulsionatore (emulsifier) 264CE
Getto massimo (main) 122
getto minimo(pilot) 45
Galleggiante (float) 11g
I am assuming this is with the unsealed airbox.
when the 500s came out though much tinkering was done in the UK
Mark

[mbmm350s]

Forgot slide is 40
The settings are for reference and as a starting point in tuning for a specific combination of engine/ exhaust air filter etc.
Mark