clearing idle jets

Thanks for reporting it, Will, and well done, Bruce! Dellortos don't seem to be afflicted by this malady (as evidenced by most Del owners superior air and condascending attitude toward the plight of us mere Weber owners)

Robert had Dellortos. 

Troy Sloan posted:

Robert had Dellortos. 

There, take that you evil Dell owners!

Troy Sloan posted:

Robert had Dellortos. 

Troy did he have Dells in the past and was he running Webers when he had the small fire on the last SOC run?

Jet doctors are made for Dell carbs as well. See attached

I attached a word doc and it may be problematic to open, here is the link for the Dell jet doctors: https://www.cbperformance.com/product-p/7348.htm

http://www.piersideparts.net/JC04.html

http://www.cbperformance.com/product-p/7351.htm

Dutch posted:

Troy Sloan posted:

Robert had Dellortos. 

Troy did he have Dells in the past and was he running Webers when he had the small fire on the last SOC run?

Robert's car was on the road for several years with Webers, but he upgraded to Dells several months ago.  The fire and clogged jets were with the Dells.  

Point is, it can happen with any carbs. 

Troy Sloan posted:

Dutch posted:

Troy Sloan posted:

Robert had Dellortos. 

Troy did he have Dells in the past and was he running Webers when he had the small fire on the last SOC run?

Robert's car was on the road for several years with Webers, but he upgraded to Dells several months ago.  The fire and clogged jets were with the Dells.  

Point is, it can happen with any carbs. 

I concurr, lots of good reasons for good filtration, a regular carb cleaning, and as I am now doing a rebuild kit for my Dells, I will add jet drs. I also add Seafoam regularly to my gas tanks in all my cars, including the 944 and the Land Rover. I've not had any issues with my Dells to date...knock on wood!

Great tip on the compressed air shot down through the suspected clogged jet.   A long nozzle tube would be especially effective, too.

Yes, Dells can get clogged jets, however the frequency seems to be much less than with Webers because of where the jet inlets are located.  Cory Drake used to spend most of his stopped time on drives cleaning his jets, and I believe that he runs Dells (don't know what air cleaners he has).

I installed the longer jet tubes (the Dellorto "Jet Doctors" in the CB Performance link up above) before I ever installed the carbs the first time, along with the Horizontal Discharge tube kits and have had, IIRC, one clogged jet since 2001.  That may have been a leaking Manifold gasket, instead (I used to have a lot of trouble with gaskets for lack of much metal between the widened intake ports).  

Don't know, that time, because I pulled the carbs/manifolds as a unit to work on them on the bench.  That was before I found out how easy it was to unclog top-mounted jets.   The Jet Doctors get the inlet to the jet way up high in the air cleaner and away from potential dust.

I also ALWAYS run a bead of automotive grease around the top and bottom surfaces of my K&N air cleaner elements, where they mate to the top/bottom covers, to act as a sealant to keep crud out.  I read about that in a K&N tech update once and thought it made a lot of sense.

Hope I don't sound too condescending........

As they say down South:  "Bless Yo' Haht!"  (Lane will get that one....)

Gordon Nichols posted:

Great tip on the compressed air shot down through the suspected clogged jet.   A long nozzle tube would be especially effective, too.

Yes, Dells can get clogged jets, however the frequency seems to be much less than with Webers because of where the jet inlets are located.  Cory Drake used to spend most of his stopped time on drives cleaning his jets, and I believe that he runs Dells (don't know what air cleaners he has).

I installed the longer jet tubes (the Dellorto "Jet Doctors" in the CB Performance link up above) before I ever installed the carbs the first time, along with the Horizontal Discharge tube kits and have had, IIRC, one clogged jet since 2001.  That may have been a leaking Manifold gasket, instead (I used to have a lot of trouble with gaskets for lack of much metal between the widened intake ports).  

Don't know, that time, because I pulled the carbs/manifolds as a unit to work on them on the bench.  That was before I found out how easy it was to unclog top-mounted jets.   The Jet Doctors get the inlet to the jet way up high in the air cleaner and away from potential dust.

I also ALWAYS run a bead of automotive grease around the top and bottom surfaces of my K&N air cleaner elements, where they mate to the top/bottom covers, to act as a sealant to keep crud out.  I read about that in a K&N tech update once and thought it made a lot of sense.

Hope I don't sound too condescending........

As they say down South:  "Bless Yo' Haht!"  (Lane will get that one....)

All good info as always Gordon, and much appreciated. I follow a lot of your input and have never experienced or felt like any of it was condescending. as the Aussies would say "Good on ya Mate"!

Just got mine running with 36 Dells and Jet Doctors.  Blew them out a few times but cylinders 3 and 4 are coughing out through the shorter jet (idle?). 

Yup, Idle running rich.

Try removing the idle mixture screws on those two throats (be careful NOT to lose the o-rings and teeny-tiny washers at the far ends of the screws) then blast some compressed air or Gumout Carb Cleaner (or equivalent) deep into the mixture screw hole.  Then shoot a blast of compressed air or Gumout down the jet tube from the top.  Put everything back together, gently bottom out the mixture screws and then back them out 2-1/2 turns.  Then, use the "Piperato Patented Mixture Screw Adjustment Procedure":  Start it up, get it warm and, one at a time, slowly turn each mixture screw in til the engine stumbles or pops in the exhaust (too lean), then slowly back it back out 1/2 to 1 turn til things even out.  

Hopefully, that will cure it.  If not, then you have an intake leak at one or more of the gaskets.  The leak could be between cylinder ports where you can't see or detect it inside of the intake runner.

You coming to Hebert's this Saturday?

My Dell 36 DRLA's were installed by Pat D. back in September last year. Based on what I know now I'd say they got clogged about two months before the SOC event in June. As with many things the problem was slow to materialize and hence I hadn't given too much thought to the little bit of hesitation on acceleration or some of the coughing and spitting the engine did while driving.

Now that I've been educated by fire, I will have a better idea as to when I HAVE to clean the idle jet. I hope to have a better handle on it and will clean them before it becomes a serious problem.

Reading this thread, I got to thinking about how often I get dirt in the idle jets, and it's not too often at all. I have Webers with no jet doctors.

The float bowls were cleaned well when the carbs were installed on the new engine and I've got two pretty basic inline filters. The second filter is the plastic see-through kind and the element looks very clean - no visible gunk at all.

I think the last time there was actually dirt in any of the jets was over 10,000 miles ago.

I love the sound this motor makes when all four jugs are pulling exactly the same. Once you hear that, it's pretty easy to tell when one or more are no longer drawing just right. But on my car at least, this is not usually because of dirt in the jets. It's usually fixed with some very slight tweaking of the mixture screws and idle stops. I'll usually check the screws and stops a few times per year as the seasons change. It's at the season change that tuning is most usually required. It's also helpful to check the slop in the hex bar linkage at the same time and to make sure the heim joints are lubed. (Yes, there's a SyncLink in my future, eventually.)

I think a lot of 'dirty jet' problems may actually be the four barrels drifting out of tune for other reasons or maybe non-carb issues like ignition or vapor in the fuel lines (from excessive heat in the engine bay).

So now I'm wondering. How many miles do you average between actual jet blockages?

By that, I mean a sudden obvious roughness that's immediately fixed by blowing out the jets.

I put Jet Doc's in my EMPI HPMX 44's (Weber knock off's) in my 550. Sounds like a good trick. 

Jeeze ! Thanks Will ! I didn't know you were gonna run my idea by Sr. Guru Pat Downs !

Just got got back from Flagstaff AZ  and have been catching up on all the latest stuff on this site !  i just had crappy experience with my car. The Left float stuck (left from the driver's seat) so I had to dig down to remove the "airhorn" part of the carb to correct the problem. This is usually "major surgery" so I expected other problems to surface when when I corrected the problem. They did !  Clogged jet in #3...Blew air down # 4 jet doctor and no change. Blew down # 3...Voila ! problem went away ! I slamed the lid shut and went to Arizona. Tomorrow i get to clean that carb to make sure the crap doesn't return. While I'm in there I'm gonna split the hex bar on my linkage and install a "micro" adjuster to allow me to compensate for the difference between the right and left carburetor linkage slop so I get a better "throttle on adjustment" between the two carbs......always something....but that's part of the madness....isn't it ?   i hope !......Bruce   PS.....the blow back thru the "Jet Doctors" is only a temporary fix to get you home where you can do major surgery !!!!!