Hello I wonder if somebody could help me out please? Is it possible for the unit below to leak? I've been trying to get new o rings but it almost looks like it has failed internally somehow. or is the fuel just wicking past the o rings and going through the body? I have trued the outside mounts to the main body where it touches the main CIS unit. previously there was a gap of about .3 mm. I reused the old o rings (just waiting for the new ones to show up) and the drip went from about one drop a second to just showing wet at the join and around the body. Still not good. So if the unit is bad- 1) What does this unit actually do? and when? just at startup or all the time? 2) Can it be replaced with plate with a channel cut into it that would pass fuel between the 2 holes? 3) Is this fairly common with other 80s era CIS 6 cylinder units Thank you for any help anyone can give! Barry Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Yes -- I've had to replace one for leaking (not at the o-rings), but trying fresh o-rings isn't a bad thing. It is the EHA (Electro Hydraulic Actuator). It is a precision valve located at the inlet to the lower chambers that is always in use whenever the engine is running: When the current supplied to the EHA is high = EHA internal valve more closed = restricts fuel entering the lower chambers = reduces lower chamber pressure = reduces upper chamber pressure = increases pressure drop across the slits = increases fuel delivered to injectors for a given size slit opening = adds richness When the current supplied to the EHA is low = EHA internal valve more open = less restriction to fuel entering the lower chambers = increases lower chamber pressure = increases upper chamber pressure = decreases pressure drop across the slits = decreases fuel delivered to injectors for a given size slit opening = more lean The default nominal KE-Jet EHA current is 10 mA; minimum current is 0 mA; max current is 20 mA. No. You've got the Bosch 10-digit PN on the body (2437020008) -- give Larry Fletcher (fletch62) CISFLOWTECH a shout if you have trouble locating it. IME, the only "easy" EHA to find recently is the one for KE3-Jet, 2437020007, but (although physically identical) it is calibrated to operate from -10mA to +10mA (nominal = 0mA) rather than from 0mA to 20mA (nominal = 10mA). Perhaps Larry can advise if it can be substituted, or if he can recalibrate.
Thank You Steve! How does the European version handle this function? Or it simply does not? It manages fuel only on vacuum and temperature somehow? I imagine it must be a different CIS unit. Thanks again Barry
The euro version F113A is K-Jet without Lambda so it has no EHAs (but has WURs for cold enrichment and WOT enrichment) The euro version F113B is KE-Jet without Lambda so it has EHAs -- but they are used just to provide cold enrichment and WOT enrichment (no O2 sensor feedback).
I should've added that these current ranges for the two EHA types are for "Lambda" operation -- during starting and WOT, the currents are larger for both.
Thanks Steve After I read your post I went back to the garage and connected the power to the unit again. The leak is back to 1 drop a second and looks to be coming out of the body of the unit. My guess is its done. What does the brass screw on the bottom do? Barry
That screw is used to calibrate the internal valve operation by acting on a spring flexure to add a mechanical force to the magnetic force -- see Fig 55 on page D76 of the TR WSM for a cross-section drawing of the EHA. That screw also has an o-ring that could leak, but if you remove the screw and replace the o-ring, you'd have to have some sort of (fairly complex) measurement equipment to reinstall it to the correct location to give X flow at Y pressure difference at Z current (if that's where the leak is coming from).
Thanks again Steve for all the information and the tip to talk to Larry I spoke to him today,very nice gentleman , very knowledgeable . He has a solution that should work very well. Barry
And it is? He can supply a new 2437020008? He can fix your 2437020008? He can recalibrate a 2437020007 to 2437020008 specs? 2437020007 is fine to use as-is? Something else?
in my TR koenig there was in 2 437 020 008. but koenig told me that this has not been the original one. so steve, do you perhaps know what has been original? the 007? I still have my complete system for sale. KE-Jetronic von Ferrari Testarossa, Mengenteiler, Druckspeicher, Kraftstoffpumpe | eBay
Hi Steve Sorry for my previous non informational response. I was just so happy to talk to Larry and find a solution. To answer your questions- "And it is? He can supply a new 2437020008?No they are NLA can fix your 2437020008? No it has delaminated from the plastic? case. He can recalibrate a 2437020007 to 2437020008 specs? This is exactly what he does. He puts the unit on flow bench and recalibrates to flow the same as a 008. You then have to tune the electrical circuit for it to work with the computer. He will provide me with the procedure and spec for the circuit. 2437020007 is fine to use as-is ? no it is physically identical but you are correct about the electrical operating range. Something else?" ? convert to electronic I did this on my 911 20 or so years ago and it has been bulletproof. Barry
Thanks again Steve for the tip to call Larry! I mounted the new units last night and adjusted the mixture tonight as per Larry's instructions. Everything worked out great! idles smooooth, snappy throttle response, starts instantly and the big one, no leaking fuel! No gas smell. Larry if you are on here Thank You as well! Barry
hello Im french and have same problem. can you tell us how to convert the ***07 to ***08 ? thanks for help nico
