I'm here slamming my head over a 1981 VW engine with K-Jet. I'd just like to thank you for showing everyone this test. Even with a different CIS it's helpful to see your setup.
The warm regulator has vacuum applied while the engine is cold. A dip in vacuum (quick acceleration) helps a spring inside the regulator slow the fuel flow of the control pressure. The temporary drop in control pressure causes a imbalance in the lower chambers resulting in higher fuel flow to the injectors.
Hello, right now I am working on a WUR with single diaphragm (0438140015) and it only has 1 vacuum connector. When I apply vaccum the control pressure drops instead of rising. Should it be that way? What values should I set it up to?
@@szymonkowalczyk2907 What is the application? Make sure that the temperature vs fuel pressure correlation is correct before getting too much into vacuum enrichment. Cold start enrichment problems are often related to a inoperative Thermo vacuum switch or a vacuum routing issue.
It is not called out in the exploded views or any of the maintenance but under that larger banjo bolt on the warm up regulator is a series of screens or filter that when clogged will cause upper fuel chamber pressure in the fuel distributor to become too high. On badly rusted fuel tanks or cruddy fuel it can block so much that it will equal system pressure +70 psi. The engine will not run well if at all / too lean. The range is between 25 & 55 psi Crack the line and drop the pressure and voila ! The engine will run. Pulling the screens can return pressure to normal. many of the rebuild kits omit the filters altogether.
Great video Tim, interesting test you have done. Maybe you can give me your opinion. My 1980 MB does not start when cold but the rest works perfectly (runs smooth, good mixture, etc.) Its K-jet has a "Gas Pressure Damper" and a restricted metal tube between the Fuel Distributor and the WUR that seems to limit the correct gas pressure release when cold so the system can not do the transition from a low to a normal Control Pressure. It starts at 4,0 bar from the first starting attempt. Do you know what is the purpose of that damper/tube arrangement? (When I bypass them, Control pressure drops dramatically and the engine stalls) Do all cars have them? how can I test the WUR disregarding that Damper/tube? Thanks!
I'm learning about the K Jetronic on Deloreans. I came across this vid that modifies the WUR. Looks like it was for VW. Is this mod a "factory adjustment procedure" used on the Deloreans? m.ruclips.net/video/PuELRd3gqgk/видео.html His other vid shows a cross section of this system.... not sure if any of this applies to the KJet used on Deloreans..... m.ruclips.net/video/Ax6O6Zhxx0E/видео.html Any thoughts?
I'm here slamming my head over a 1981 VW engine with K-Jet. I'd just like to thank you for showing everyone this test. Even with a different CIS it's helpful to see your setup.
Your welcome. Glad I could help.
The warm regulator has vacuum applied while the engine is cold. A dip in vacuum (quick acceleration) helps a spring inside the regulator slow the fuel flow of the control pressure. The temporary drop in control pressure causes a imbalance in the lower chambers resulting in higher fuel flow to the injectors.
Hello, right now I am working on a WUR with single diaphragm (0438140015) and it only has 1 vacuum connector. When I apply vaccum the control pressure drops instead of rising. Should it be that way? What values should I set it up to?
@@szymonkowalczyk2907 What is the application? Make sure that the temperature vs fuel pressure correlation is correct before getting too much into vacuum enrichment. Cold start enrichment problems are often related to a inoperative Thermo vacuum switch or a vacuum routing issue.
what would happen if you would bypass the WUR?
It is not called out in the exploded views or any of the maintenance but under that larger banjo bolt on the warm up regulator is a series of screens or filter that when clogged will cause upper fuel chamber pressure in the fuel distributor to become too high. On badly rusted fuel tanks or cruddy fuel it can block so much that it will equal system pressure +70 psi. The engine will not run well if at all / too lean. The range is between 25 & 55 psi Crack the line and drop the pressure and voila ! The engine will run. Pulling the screens can return pressure to normal. many of the rebuild kits omit the filters altogether.
Great video.. what does the top vaccum connection do?
I believe it’s a atmospheric vent if I’m remembering correctly.
Great video Tim, interesting test you have done. Maybe you can give me your opinion. My 1980 MB does not start when cold but the rest works perfectly (runs smooth, good mixture, etc.) Its K-jet has a "Gas Pressure Damper" and a restricted metal tube between the Fuel Distributor and the WUR that seems to limit the correct gas pressure release when cold so the system can not do the transition from a low to a normal Control Pressure. It starts at 4,0 bar from the first starting attempt. Do you know what is the purpose of that damper/tube arrangement? (When I bypass them, Control pressure drops dramatically and the engine stalls) Do all cars have them? how can I test the WUR disregarding that Damper/tube? Thanks!
I'm learning about the K Jetronic on Deloreans. I came across this vid that modifies the WUR. Looks like it was for VW. Is this mod a "factory adjustment procedure" used on the Deloreans?
m.ruclips.net/video/PuELRd3gqgk/видео.html
His other vid shows a cross section of this system.... not sure if any of this applies to the KJet used on Deloreans.....
m.ruclips.net/video/Ax6O6Zhxx0E/видео.html
Any thoughts?