mysubie Posted August 30, 2006 Share Posted August 30, 2006 I was wondering if anyone else has needed to rejet their weber carb? I have an 1987 Subaru Standard HB. I was told that if someone had the same vehicle as me they may have some specs on the jet sizes used. We believe that the fuel to air ratio is running to rich and are planning on doing the idle jet first to see if this improves the issue with warm and cold idle speeds, desiling, and gas milage. I was also wondering if a fuel shut-off solenoid would help much with these issues. The idle screw is 6 or 7 turns out when it is only supposed to be 2 turns. This causes the car to run poorly when cold but better when it is all warmed up....But it is still desiling. Thanks for any input! Link to comment Share on other sites More sharing options...
monstaru Posted August 30, 2006 Share Posted August 30, 2006 start at your base tunings and move up from there. Link to comment Share on other sites More sharing options...
Petersubaru Posted August 30, 2006 Share Posted August 30, 2006 base is as stated from weber / 2 turns out and is a good place to start..6-7 turns out would mean that the primary jet is to small and possibly needs to be larger..this carb is very difficult to tune "properly" for the first timer...what is the jet size for the primary you are useing / also what is the jet size for the secondary... I was wondering if anyone else has needed to rejet their weber carb? I have an 1987 Subaru Standard HB. I was told that if someone had the same vehicle as me they may have some specs on the jet sizes used. We believe that the fuel to air ratio is running to rich and are planning on doing the idle jet first to see if this improves the issue with warm and cold idle speeds, desiling, and gas milage. I was also wondering if a fuel shut-off solenoid would help much with these issues. The idle screw is 6 or 7 turns out when it is only supposed to be 2 turns. This causes the car to run poorly when cold but better when it is all warmed up....But it is still desiling. Thanks for any input! Link to comment Share on other sites More sharing options...
GeneralDisorder Posted August 30, 2006 Share Posted August 30, 2006 You need to check your jets: 140/140 mains. 170/160 air bleeds 50, 55, or 60 idle will work - I like the 50 myself. GD Link to comment Share on other sites More sharing options...
Petersubaru Posted August 30, 2006 Share Posted August 30, 2006 What are you useing for the secondary jet..maybe a 60???... You need to check your jets: 140/140 mains. 170/160 air bleeds 50, 55, or 60 idle will work - I like the 50 myself. GD Link to comment Share on other sites More sharing options...
GeneralDisorder Posted August 30, 2006 Share Posted August 30, 2006 What are you useing for the secondary jet..maybe a 60???... Huh? Both mains (primary and secondary) are 140..... what are you refereing to with "60"?? GD Link to comment Share on other sites More sharing options...
Petersubaru Posted August 30, 2006 Share Posted August 30, 2006 as I understand the terminology, no reference has been made to the "mains"...we are probably saying the same thing but differently...It might be a little difficult to explain for me, but I will try..the idle jet (primary) located on the front/choke side ...maybe #60....and the "secondary" which is located on the back side of the carb...this jet is usually less in size..like maybe a #50 if you are useing #60 up front... Huh? Both mains (primary and secondary) are 140..... what are you refereing to with "60"?? GD Link to comment Share on other sites More sharing options...
mysubie Posted August 30, 2006 Author Share Posted August 30, 2006 I still need to take the carb apart and find out what size of jets are there. Apparently this model either comes with matching main idle jets or two different sizes. Is there an easier way to find out? Are these specs for a completely rejetted 32-36 DGEV carb or just the idle jet 140/ 140 170/160 60/50 Thanks Link to comment Share on other sites More sharing options...
GeneralDisorder Posted August 30, 2006 Share Posted August 30, 2006 as I understand the terminology, no reference has been made to the "mains"...we are probably saying the same thing but differently...It might be a little difficult to explain for me, but I will try..the idle jet (primary) located on the front/choke side ...maybe #60....and the "secondary" which is located on the back side of the carb...this jet is usually less in size..like maybe a #50 if you are useing #60 up front... Those are just the idle jets. I'm refereing to all the jets in my original post. You don't need a secondary idle jet - often they are the same as the primary though. GD Link to comment Share on other sites More sharing options...
GeneralDisorder Posted August 30, 2006 Share Posted August 30, 2006 I still need to take the carb apart and find out what size of jets are there. Apparently this model either comes with matching main idle jets or two different sizes. Is there an easier way to find out? Are these specs for a completely rejetted 32-36 DGEV carb or just the idle jet 140/ 140 170/160 60/50 Thanks Nope - have to open it up. Those specs are proper base jetting for a subaru (plus tons and tons of other small engines). It will run very well with excelent mileage. You wouldn't have to change these unless you are racing or modifiying your cam or something. GD Link to comment Share on other sites More sharing options...
bigjim5551212 Posted August 31, 2006 Share Posted August 31, 2006 the secondary idle doesnt do very much. it may help with a hesitation when the secondary barrel opens Link to comment Share on other sites More sharing options...
Petersubaru Posted August 31, 2006 Share Posted August 31, 2006 new from the factory the secondary idle jet is smaller then the primary idle jet... from my own experience, if I ran 2 idle jets of the same size it would bog down(getting to much gas in my cause)...I was able to get rid of the hesitation off the line by dropping the idle RPM speed and increasing the timing a bit...for example..timed at 12deg/750-800rpm... idle speed would remain the same at 800..If I bumped the idle speed up to 1000rpm and was now useing this as my starting point off the line, it would hesitate every time..also at times it would back fire up thru the carb indicating a "timing" related problem..everything works very smoothly now in my daughters car....hope this helps... the secondary idle doesnt do very much. it may help with a hesitation when the secondary barrel opens Link to comment Share on other sites More sharing options...
bigjim5551212 Posted September 1, 2006 Share Posted September 1, 2006 Your primary idle jet is too small. The way it works is this. If you have the idle mixture screw open, say 7 turns, then you are not getting enough fuel. To prove it, your engine diesels when you turn it off. This is because the temperature in the combustion chamber is higher than normal, and therefore, the carbon that sits around glows red hot. You turn off ignition, and the engine still sucks gas, it gets to the combustion chamber and the glowing carbon doesnt need the spark to keep fuel burning. you need one or two sizes bigger than what you have. I can help you, call me at 604 879 6288, ask for Jim. Our business sells weber parts among others Link to comment Share on other sites More sharing options...
mysubie Posted September 2, 2006 Author Share Posted September 2, 2006 Thanks everyone... will be looking at my carb soon Link to comment Share on other sites More sharing options...
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