CIS K-Jet Rebuild Completed
#17
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Thanks to everyone for your positive feedback. My CIS gurus pointed out that there is I could have improved the write up in one area, how to be sure the center stainless steel plate is properly oriented to the top and base of the fuel distributor. This attached picture provides a big HINT.
I created an addendum to the article and sent that to everyone that already asked for the article and created a new article verion and am now sending that for new requests. If you recieved the orginal article and didn't get an addendum, drop me a line and I'll send it (or the new version).
I created an addendum to the article and sent that to everyone that already asked for the article and created a new article verion and am now sending that for new requests. If you recieved the orginal article and didn't get an addendum, drop me a line and I'll send it (or the new version).
#18
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Forgive my ignorance, but what would be a sign that the fuel distributor needs rebuilt? I'm probably going to be a shark owner within three weeks or so, and I'm trying to research any PM type stuff I need to do, especially with the CIS.
#19
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IMHO, it would be last thing to do, depending on symptoms. Mostly likely if car has sat unused for a long time, and if the system pressure is wrong, poor delivery at injectors, etc. Start at the fuel filter, both internall and external, pump check valve, accumulator. Get the injectors cleaned, run some Techron through it. Measure the pressures. Get a copy of Ben Watson, and a gauge set from Whitneys. Pray your WUR is good - if not flush with cleaner back and forth. I get misfires a couple of times a year, and my wrench says that means there is dirt in the distributor clogging a slit - clears if I relieve pressure by opening any fitting. At this frequency, its not worth fixing yet.
jp 83 Euro S AT 48k, BTDT.
jp 83 Euro S AT 48k, BTDT.
#20
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So what would CIS PM consist of on an Euro '83? I use techron in my Audi and 4Runner every oil change anyway, would you need to pull the injectors and clean them with something else? Also, would a car that's grumpy when it's cold probably be a symptom of a WUR problem? I'm trying to get a good idea of CIS and avoiding problems with it, are there any good web tutorials on it?
#21
The operation of the distributor is linear. If the car doesn't run well when cold but runs OK when warm look elsewhere (cold start system). Symptoms of a bad distributor are lean or rich running on one or more injectors when the system and control pressures check OK and AF adjustments won't bring it into spec. Also dumping of fuel into the lower plenum is a postive sign your distributor need rebuilt.
Dennis
Dennis
#22
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Get a copy of Ben Watson, he has a good list of problems in CIS, and what to look at for each. Grumpy when cold (ie rough, poor response) sounds like high control pressure producing too lean a mixture for the temp. You MUST check the pressures before going anywhere else, and localize the cause of the problem. On my car, it NEVER misses a beat stone cold - I can get up a sharp hill within a minute of firing up. CIS is VERY intolerant of air leaks (ie vacuum hoses etc) also.
PM as such - fuel filter regularly, Techron before each oil change is about it. DOnt let it stand for long periods unused.
jp 83 Euro S AT 48k
PM as such - fuel filter regularly, Techron before each oil change is about it. DOnt let it stand for long periods unused.
jp 83 Euro S AT 48k
#23
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Another excellent reference is Bosch Fuel Injection & Engine Management by Charles O. Probst, SAE. Robert Bently is the publisher. ISBN 0-8376-03005. This book also covers electronic fuel injection systems.
#25
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Go here
http://www.amazon.com/exec/obidos/tg...47011?v=glance
enter into google 'watson amazon bosch' . Best $15 you will spend. Probst is good, but Watson gives troubleshooting guide, and practical advice, as well as how they work.
jp 83 Euro S AT 48k.
http://www.amazon.com/exec/obidos/tg...47011?v=glance
enter into google 'watson amazon bosch' . Best $15 you will spend. Probst is good, but Watson gives troubleshooting guide, and practical advice, as well as how they work.
jp 83 Euro S AT 48k.
#26
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I've contributed my K-Jet CIS rebuild article to the 928 Owners Club (www.928oc.org). I will soon be available for download from the Journal section of the website.
#27
Developer
jpitman2 - If you can find those sizes, I'd be interested too. So far, they have escaped me.
BTW - the plunger piston is married to the plunger body with very, very close tolerances. Do NOT drop it - if you do, the fuel distributor is likely ruined. Do not sand it or emery-cloth it. It cannot
be "swapped" into another fuel distributor. You cannot take two fuel distriubutors and make one.
BTW - the plunger piston is married to the plunger body with very, very close tolerances. Do NOT drop it - if you do, the fuel distributor is likely ruined. Do not sand it or emery-cloth it. It cannot
be "swapped" into another fuel distributor. You cannot take two fuel distriubutors and make one.
#28
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Carl,
Can you be any more specific on the two problem O ring sizes? Is the small (7mm ID?) 2.5 or 3mm section? Is the larger one 2.5mm section, and is ID 27.5, or ?
jp 83 S
Can you be any more specific on the two problem O ring sizes? Is the small (7mm ID?) 2.5 or 3mm section? Is the larger one 2.5mm section, and is ID 27.5, or ?
jp 83 S
#29
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Carl,
My first source says he can do these in Viton (high temp stuff), almost no problem. There is no 27.5 diameter ring - 27 or 28mm ID. Just a $2 mincharge per line item. Big deal.
SO question is, what exactly are the sizes? Some care needed here...as I read Rich's note:-
35 ID x 39 OD x 2 section 1 off
22 26 2 2
8 12 2 8
7 ? 2.5 1 really 2.5??
?27 ?30 2.5 1 ?? diameters??
If I can find these in Oz, you should be able to locate in USA....? Are we that much more metric than you?
thanks,
jp 83 S
My first source says he can do these in Viton (high temp stuff), almost no problem. There is no 27.5 diameter ring - 27 or 28mm ID. Just a $2 mincharge per line item. Big deal.
SO question is, what exactly are the sizes? Some care needed here...as I read Rich's note:-
35 ID x 39 OD x 2 section 1 off
22 26 2 2
8 12 2 8
7 ? 2.5 1 really 2.5??
?27 ?30 2.5 1 ?? diameters??
If I can find these in Oz, you should be able to locate in USA....? Are we that much more metric than you?
thanks,
jp 83 S
#30
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Go to www.amseal.com - my supplier is local branch of Amseal! They list all sorts of stuff under O-rings & backups - Metric Orings in Buna - is that ok for Gasoline? Anyway, in there are 27x 2,2.5,3,4,mm; 28 x 1.5,2,2.5,3,4,5; 29x 2.5,3mm; 7x 2,2.5,3mm and some fractional sizes that are probably inch sizes converted to mm. Viton range looks smaller...
jp 83 S
jp 83 S