Original Posted By: "skellytown flyer"
ooops!Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: throttle and brakes
Pietenpol-List: throttle and brakes
Re: Pietenpol-List: throttle and brakes
Original Posted By: Ryan Mueller
Well I am finally getting a little progress on my left brake on my project- theyare old 1947 dated multiple segment Hayes brakes with a rubber expansion bladderand Gerdes master cylinders attached to the rudder pedals. I am wonderingif that style piston master cylinder has enough volume to really expand the oldbrakes enough. the right one worked fairly well but the left one wouldn't.I just finished putting .025" shims under most of the shoe segments on that sideand got them to work though the drum does get kinda warm after extended taxi.if it doesn't break in soon I guess I'll do something else.also the Stromberghas a bad dead spot. as it comes off idle. it was rebuilt according to thetag that I got with DJ's paperwork.looks nice and clean inside but I have a hardtime getting it to take throttle especially till it warms up real good.onceit is past maybe a 1/2" on the lever it goes ahead and runs up great. and I haveplayed with the idle screw and probably have it at 1 3/4 turns out now.noreal improvement- seemed to run worse at 2 1/2 turns.it is mounted with the bowlside against the firewall and the throttle shaft forward. I thought that couldpossibly be an issue with the tail down, but raising the tail doesn't seemto help. also I can hit the primer when it's stumbling and trying to take powerand it kills it so that tells me it is rich rather than lean at that point.sometimespulling carb heat seemed to help some but there sure isn't any icinghere with the humidity as low as it is in the Texas panhandle right now.the mixtureis wired full rich.it runs plenty strong if you can get it to go past thedead spot.just wondering if any of you have run into similar issues with yourStromberg? RaymondRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Sat, 16 Oct 2010 17:44:10 -0500Subject: Re: Pietenpol-List: throttle and brakes
Well I am finally getting a little progress on my left brake on my project- theyare old 1947 dated multiple segment Hayes brakes with a rubber expansion bladderand Gerdes master cylinders attached to the rudder pedals. I am wonderingif that style piston master cylinder has enough volume to really expand the oldbrakes enough. the right one worked fairly well but the left one wouldn't.I just finished putting .025" shims under most of the shoe segments on that sideand got them to work though the drum does get kinda warm after extended taxi.if it doesn't break in soon I guess I'll do something else.also the Stromberghas a bad dead spot. as it comes off idle. it was rebuilt according to thetag that I got with DJ's paperwork.looks nice and clean inside but I have a hardtime getting it to take throttle especially till it warms up real good.onceit is past maybe a 1/2" on the lever it goes ahead and runs up great. and I haveplayed with the idle screw and probably have it at 1 3/4 turns out now.noreal improvement- seemed to run worse at 2 1/2 turns.it is mounted with the bowlside against the firewall and the throttle shaft forward. I thought that couldpossibly be an issue with the tail down, but raising the tail doesn't seemto help. also I can hit the primer when it's stumbling and trying to take powerand it kills it so that tells me it is rich rather than lean at that point.sometimespulling carb heat seemed to help some but there sure isn't any icinghere with the humidity as low as it is in the Texas panhandle right now.the mixtureis wired full rich.it runs plenty strong if you can get it to go past thedead spot.just wondering if any of you have run into similar issues with yourStromberg? RaymondRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Sat, 16 Oct 2010 17:44:10 -0500Subject: Re: Pietenpol-List: throttle and brakes
Pietenpol-List: Re: spoked rim sizes?
Original Posted By: "bubbleboy"
Well I have not been able to contact DJ lately- he may have changed his address.but I have a yellow tag from a shop in Conroe Texas dated 10-1-01 that statesthey overhauled and tested a Sromberg for C90-12F ,in accordance with NA-S3A1service manual for Stromberg Carburetors. I guess I could go back and removeit and make sure the serial number matches. I did not do that/otherwise I hada theory that maybe it's a little rich and the only way to lower the float levelin them I can see is to add a thicker washer under the seat. the old brassfloats are heavy duty and not made to bend to adjust.I am not getting the idlescrew to help as far as doing away with the dead spot.RaymondRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: spoked rim sizes?
Well I have not been able to contact DJ lately- he may have changed his address.but I have a yellow tag from a shop in Conroe Texas dated 10-1-01 that statesthey overhauled and tested a Sromberg for C90-12F ,in accordance with NA-S3A1service manual for Stromberg Carburetors. I guess I could go back and removeit and make sure the serial number matches. I did not do that/otherwise I hada theory that maybe it's a little rich and the only way to lower the float levelin them I can see is to add a thicker washer under the seat. the old brassfloats are heavy duty and not made to bend to adjust.I am not getting the idlescrew to help as far as doing away with the dead spot.RaymondRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: spoked rim sizes?
Original Posted By: "Gary Boothe"
Hi Gary....sounds like a good idea. Will look into some thing like that.Looking at the Sportster rims, did you use the 2.15" or the 2.5" wide? I thinkI like the 2.5" although would add to the weight I would imagine.Just looking on a web site, it appears the Sportsters from 2008 on wards came outwith 1" bearings rather than the 3/4".Scotty--------ScottyTamworth, AustraliaBuilding a Corvair Powered Pietenpol Air Camperwww.scottyspietenpol.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Hi Gary....sounds like a good idea. Will look into some thing like that.Looking at the Sportster rims, did you use the 2.15" or the 2.5" wide? I thinkI like the 2.5" although would add to the weight I would imagine.Just looking on a web site, it appears the Sportsters from 2008 on wards came outwith 1" bearings rather than the 3/4".Scotty--------ScottyTamworth, AustraliaBuilding a Corvair Powered Pietenpol Air Camperwww.scottyspietenpol.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
RE: Pietenpol-List: Re: spoked rim sizes?
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Scotty,Mine are 2 1/2" rims. I forgot to mention...on the axle, the first step down is welded to the mainaxel by drilling a 1/4" hole in the main axle to expose the first piece. Ithen could weld that piece to the main axle and fill the hole with weld.The second piece, the one that is the axle thru the wheel bearing isthru-bolted to the main axle and the step-down. That way, if I have underengineered the axle, I can un-bolt it, slide it out, and replace with asolid axle.Gary Boothe Cool, Ca. Pietenpol WW Corvair Conversion, Running! Tail done, Fuselage on gear (21 ribs down.) -----Original Message-----
Scotty,Mine are 2 1/2" rims. I forgot to mention...on the axle, the first step down is welded to the mainaxel by drilling a 1/4" hole in the main axle to expose the first piece. Ithen could weld that piece to the main axle and fill the hole with weld.The second piece, the one that is the axle thru the wheel bearing isthru-bolted to the main axle and the step-down. That way, if I have underengineered the axle, I can un-bolt it, slide it out, and replace with asolid axle.Gary Boothe Cool, Ca. Pietenpol WW Corvair Conversion, Running! Tail done, Fuselage on gear (21 ribs down.) -----Original Message-----
Pietenpol-List: Re: throttle and brakes
Original Posted By: Harvey Rule
Yes it does make sense- I never open an aircraft throttle fast.and no matter howslow I try to open it -it still tries to die unless I pull it back to idle-butsometimes I seem to be able to pull it back and when it starts to level backout open it fairly quickly -to a point maybe 1/2" or so in travel it gets pastthe stumbling point and picks up-then it does OK from there on.I have wonderedabout the design of the intake where it divides to the two runners going upto the heads.it is a 90 degree elbow with the carb neck welded in the centerof it and it could be possible at some flow rate I guess that it could just betoo turbulent? probably not.anyway it is odd and repeatable.and seems to getbetter as the head temp gets up over 200. and also it did seem at times likethe carb heat being on helped some but I do not like running it on the groundlike that since I fly from dirt. runwayRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Yes it does make sense- I never open an aircraft throttle fast.and no matter howslow I try to open it -it still tries to die unless I pull it back to idle-butsometimes I seem to be able to pull it back and when it starts to level backout open it fairly quickly -to a point maybe 1/2" or so in travel it gets pastthe stumbling point and picks up-then it does OK from there on.I have wonderedabout the design of the intake where it divides to the two runners going upto the heads.it is a 90 degree elbow with the carb neck welded in the centerof it and it could be possible at some flow rate I guess that it could just betoo turbulent? probably not.anyway it is odd and repeatable.and seems to getbetter as the head temp gets up over 200. and also it did seem at times likethe carb heat being on helped some but I do not like running it on the groundlike that since I fly from dirt. runwayRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
RE: Pietenpol-List: Stromberg carbs
Original Posted By:> taildrags(at)hotmail.com
I just switched over from a Marvel Shebler to a Stromberg due to the AME feeling that the Marvel may have had a float problem.The only one we could find around was the Stromberg.Not sure how it will work out.One problem we had to fix right away was the fuel line needed to be longer by about 3 inches .Still waiting for new fuel line so I can't test it.Sure hope everything works out OK.With the old carb I had to constantly prime in order to start thus the reason for the AME to believe there might be a float problem.Once the engine did start with the Marvel it did have a problem with throttling up as well which it never had before.Perhaps that may have been part of the float problem too.Nothing but engine problems this summer=2Cone thing after another preventing me from flying.Very frustrating season for me.Here's hoping next season will be better!
I just switched over from a Marvel Shebler to a Stromberg due to the AME feeling that the Marvel may have had a float problem.The only one we could find around was the Stromberg.Not sure how it will work out.One problem we had to fix right away was the fuel line needed to be longer by about 3 inches .Still waiting for new fuel line so I can't test it.Sure hope everything works out OK.With the old carb I had to constantly prime in order to start thus the reason for the AME to believe there might be a float problem.Once the engine did start with the Marvel it did have a problem with throttling up as well which it never had before.Perhaps that may have been part of the float problem too.Nothing but engine problems this summer=2Cone thing after another preventing me from flying.Very frustrating season for me.Here's hoping next season will be better!
Original Posted By: "Donald Lane"
Thanks again Oscar-guess I know what to tackle next time I get a day off.good tohave a tip on where to start.I may wish I had put zippers on this thing insteadof screws before this is over. RaymondRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Thanks again Oscar-guess I know what to tackle next time I get a day off.good tohave a tip on where to start.I may wish I had put zippers on this thing insteadof screws before this is over. RaymondRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Pietenpol-List: Re: Stromberg carbs
Original Posted By: "skellytown flyer"
> >> > > Raymond wrote:> > >I am not getting the idle screw to help as far as> >doing away with the dead spot.> > If you look at the way the Stromberg carb is set up=2C you'll> see that the idle circuit opens up into the throat of the> carb right where the throttle butterfly plate contacts the> wall of the throat. In fact=2C when you pull back the throttle> all the way back to idle=2C that's the only time there is> enough 'signal' for the carb to pull fuel through that> circuit. You can see this by looking at Neal Wright's> diagram of the carb fuel circuits on pg. 2=2C here:> http://www.bowersflybaby.com/tech/Stromberg%20stuff.pdf> and the idle fuel circuit is sort of in violet.> > By design=2C then=2C adjusting the idle mixture screw> should only affect the engine operation when the throttle> is at idle and your problem is not at idle... it's in the> first opening of the throttle as you come off of idle.> > >From Harry Fenton=2C on the FlyBaby site: "Your stumble is> probably due to blocked or obstructed bleed hole. If one> of the bleed holes which serves as the transition from idle> to higher power settings is blocked=2C the engine will stumble.> Another possibility is that the holes where the throttle shaft> passes through the carb body are worn. If too much air is> pulled through the holes=2C then the mixture will lean out and> the carb will stumble until more fuel is available. If the> engine was previously used on a homebuilt=2C then perhaps the> carb air box was too small."> > "If you look into the carb throat=2C there is an extremely> small hole just above the butterfly valve in the carb throat> which opens up a circuit from idle to mid-range power.If this> passage is obstructed=2C then the carb will stumble as the> throttle is advanced through the 1300-1500 rpm range.DO NOT> use compressed air to blow through the passage as you run the> very likely risk of pulling a sudden vacuum in the float chamber> and the float can implode or distort.The most correct way to> clear this passage would be to disassemble the carb and try to> clear out the passage with an ultrasonic cleaner." > > > Oscar Zuniga> Air Camper NX41CC> San Antonio=2C TX> mailto: taildrags(at)hotmail.com> website at http://www.flysquirrel.net > ============================================> > > ________________________________________________________________________________Subject: Pietenpol-List: Re: Stromberg carbs
> >> > > Raymond wrote:> > >I am not getting the idle screw to help as far as> >doing away with the dead spot.> > If you look at the way the Stromberg carb is set up=2C you'll> see that the idle circuit opens up into the throat of the> carb right where the throttle butterfly plate contacts the> wall of the throat. In fact=2C when you pull back the throttle> all the way back to idle=2C that's the only time there is> enough 'signal' for the carb to pull fuel through that> circuit. You can see this by looking at Neal Wright's> diagram of the carb fuel circuits on pg. 2=2C here:> http://www.bowersflybaby.com/tech/Stromberg%20stuff.pdf> and the idle fuel circuit is sort of in violet.> > By design=2C then=2C adjusting the idle mixture screw> should only affect the engine operation when the throttle> is at idle and your problem is not at idle... it's in the> first opening of the throttle as you come off of idle.> > >From Harry Fenton=2C on the FlyBaby site: "Your stumble is> probably due to blocked or obstructed bleed hole. If one> of the bleed holes which serves as the transition from idle> to higher power settings is blocked=2C the engine will stumble.> Another possibility is that the holes where the throttle shaft> passes through the carb body are worn. If too much air is> pulled through the holes=2C then the mixture will lean out and> the carb will stumble until more fuel is available. If the> engine was previously used on a homebuilt=2C then perhaps the> carb air box was too small."> > "If you look into the carb throat=2C there is an extremely> small hole just above the butterfly valve in the carb throat> which opens up a circuit from idle to mid-range power.If this> passage is obstructed=2C then the carb will stumble as the> throttle is advanced through the 1300-1500 rpm range.DO NOT> use compressed air to blow through the passage as you run the> very likely risk of pulling a sudden vacuum in the float chamber> and the float can implode or distort.The most correct way to> clear this passage would be to disassemble the carb and try to> clear out the passage with an ultrasonic cleaner." > > > Oscar Zuniga> Air Camper NX41CC> San Antonio=2C TX> mailto: taildrags(at)hotmail.com> website at http://www.flysquirrel.net > ============================================> > > ________________________________________________________________________________Subject: Pietenpol-List: Re: Stromberg carbs