Dell'Orto PHF 32, What is this?

M

MotoJouni

Hero member
Location
Finland
Had a lot of problems with the carbs and never got them to work. One of the carbs has been lean I think for some reason on small throttle openings, even thought everything being equal and clean, new gaskets, jets, emulsifiers, needles etc. Just opened the carbs (again and again) and found this.

On the center cylinder carb, there is a some kind of pipe made of brass under the pilot jet on the carb body. The other carbs don't have it and the part pic or list doesn't know this kind of part. All of the carbs has a long thread under the pilot jet, like a position in where to fit the part. I couldn't screw it out and ruined it a littlebit, it has a quite small hole on it clearly resticting the idle circuit.

The pic is quite dark. What to do next, drill it away to make every carb equal or what?
 

Attachments

  • P1010963_30puna.JPG
    P1010963_30puna.JPG
    116 KB · Views: 45
Here is a better pic of it. I tried to drill it a littlebit before taking the foto. Now you can laugh if I need to buy a new carb after doing it.  :D

The same carb had clearly more black dirt inside than others indicating it is the same that has been lean and banged.
 

Attachments

  • P1010965otos.JPG
    P1010965otos.JPG
    94.6 KB · Views: 47
my very best guess is someone screwed in a pilot jet too tight, snapped the head off it, couldn't get it out, and left it in there, maybe drilled down a bit so a new pilot could be screwed in over top of it. Just a guess of course, but there should not be anything down there, you say it is brass, the pilot jet is brass....

have you tried an extractor for broken bolts?

you clearly are going to have to get whatever it is out of there, or swap in another carb body.

Paul LeClair
 
Thanks for the responce,

At least it is not a standard pilot jet for PHF or made of. It seems to be quite long, lenght behind the pilot jet to the end of the thread, it ends just before the angled drilling starts. Shape is more like a very small emulsifier.
 
Only on this carb?
If so then I would replace it if you can't extract it.
 
Yes it is only on one carb.

I try to drill it more on the bench drill next. I need to be very carefull not to damage the thread. I try a drill that is smaller than the hole, then try to carefully extract the remainings someway like using a small screw driver etc. Let's see what happens.
 
This is just a guess: It is an idle emulsion tube that came to later PHF's.

One seller sells a new PHF 32 with code "R4695" having a "BF1 Idle emulsion tube". If that is the case my bike has different versions of carburettors.
 
Have you checked the markings on the carbs are they the same for the right one as the centre one on the small pad near the top.
at a guess you are looking to extract one of these widgets i suspect, it may be that someone at some time has changed your carb over...
 

Attachments

  • 12530.jpg
    12530.jpg
    8 KB · Views: 8
^Yes the left is DS and center and right are DD's. But there is still different versions of them and don't know how to identify them.

For example I bought a larger carburettor to my LB 125, actually PHBH 30 that was factory optional, and then later found it was a four stroke version of it when disassembled. 2 and 4 stroke versions has at least different main circuits (and machined differently) but look like similar to me from outside having similar numbers.

This is the SFC 1000 Classic 1989, actually completed in Germany not in Italy. It is one from the last batch of 30 bikes of three cylindered Breganzies. It seem to have a lot of grade-B parts. My guess is that someone have had a pair of PHF 32's and then one carb was missing. There is casted numbers "81" inside the float chambers on left and right carb, I think it means casted in 1981. And then they just bought one new PHF 32 to assemble the bike. On the center carb there is no such marking casted inside the float camber.
 
Bloody mystery then if it is an emulsifier tube then i would try with a left hand drill bit and your drill in reverse as the drill might grab and turn the sucker back out.
Be interesting to see what it ends up being am sure that if you end up needin a new carb body there would be loads about what with all the Mikuni converts out there
Keep us posted hey
 
Got it extracted and didn't even ruined the body. I used a bench drill, small cordless drill and some very small screw drivers. It took for three hours to do it as carefully as needed not to ruin carb body.

Yes it was an idle emulsifier, it had several small holes on sides of it. There was marking on it "BF2", if there was more letters those are gone.
 
Got the carburettors assembled late last night and assembled to bike. But I didn't dared to wake up whole neighbourhood then to try how she runs. Today it took for hours for adjusting it properly.

Just get back home from test ride. Much better now. Somewhere on the progression range it previously pulled with two cylinders and braked with one I think. That's gone now. Very littlebit blurring somewhere in the progression still occurs but I didn't noticed any backfiring anymore.
 
You must log in or register to reply here.
Back
Top