Does anyone know if there is a rebuild kit for the W116 Fuel Distributor? 1979 450 SEL. Part # 0438100012. My mechanic says they used to sell them and he has done them before but we can not find anything. Thanks in advance for any info.
Bill
Never seen or heard of a fuel distributor rebuild kit.
A quick search brings up a Porsche pdf which describes rebuilding 6 cylinder fuel distributor, it gives the required o-ring sizes which I bet would be the same as an 8.
Fuel Distributor Rebuild (http://www.google.com.au/url?sa=t&source=web&ct=res&cd=1&ved=0CAwQFjAA&url=http%3A%2F%2Fwww.porsche928forums.com%2Fdownload%2Fmanuals%2FCISRebuild.pdf&rct=j&q=bosch+fuel+distributor+rebuild+kit&ei=TINTS4i3JcGGkQWs09mdDQ&usg=AFQjCNH3_E6K45yVbwQZFzmGM45tqp8hBg).
Edit: A closer look at the pdf shows it to be an 8 not a 6.
koan
You can buy rebuild kits for the primary pressure regulator on the rear of the FD. These are available at AutohausAZ and other places. Sometimes these get carelessly referred to as FD rebuild kits, when really its only a kit for the pressure regulator part of the FD.
Quote from: s class on 18 January 2010, 02:57 AM
You can buy rebuild kits for the primary pressure regulator
Forgot about that, sorry if I misled.
koan
Thanks guys. Sounds like buying a rebuilt one is the way to go.
I've known people that rebuilt these at home. From what I understand, the trick is to remove the springs and put them back exactly as they were taken out as they are weighted differently. If you put them back in random order, the fd will run like crap.
O rings were sourced from a hardware store.
I've had good luck at soaking them in parts cleaner.
What do yo mean by parts cleaner? Its not a term we use here in South Africa. Do you mean like carb cleaner, or brake clean or what?
Quote from: s class on 20 January 2010, 03:00 AM
What do yo mean by parts cleaner? Its not a term we use here in South Africa. Do you mean like carb cleaner, or brake clean or what?
I've used soaked FD's that were completely gummed up and with a frozen piston in Berryman's carb cleaning solution for about a week and managed to free them up. They now work fine. Brake clean would probably do just fine and i've used that stuff in a car to clean the injectors on CIS cars.
A friend who works as a mechanic used the stuff that they buy for professional parts cleaners. I'm not sure what it's called.
If you want your car to run right pull your FD and WUR and send them both to Larry Fletcher at CIS Flow Tech in Alabama. Great guy and knows CIS inside out. I recently sent him a WUR from my 6.9. It left my work Monday morning and arrived rebuilt at my home mid morning on Friday of the same week. If the inside of your FI get corroded you can soak it in whatever you like till the cows come home and it still won't run exactly right. If you spend a little bit of money and get both rebuilt and correctly calibrated it will be some of the best money you ever spent and you will be reminded of that everytime you drive your car. - Tom
Do you have his contact info? website? I know what FD is but what is WUR?
I assume it is http://www.cisflowtech.com/ ???
Be careful when ordering o-rings. Early K-Jet versions used a round o-ring and later K Jet models used a squared o-ring.
Quote from: Nutz on 07 February 2010, 07:25 PM
Be careful when ordering o-rings. Early K-Jet versions used a round o-ring and later K Jet models used a squared o-ring.
Which O-Rings changed, was it the eight that connect the metering slits to cast iron body ?
I ask because I have a spare fuel distributor I was going to attempt a rebuild of.
koan
With pompy's 450, the original FD is locked solid. We got a (apparently) god used one, but I'm still a little suspicious of the used one, as it shows signs of having been opened before. I would prefer to rebuild the original one if at all possible. As to the o-rings around the metering slits - how on earth does one get those back in place after stripping?
Other question is when re-mounting the two halves of the body - there is no gasket or sealant or anything - I presume it just relies on meticulous cleanliness for a metal-to-metal seal capable of holding the required pressures.
Quote from: koan on 08 February 2010, 12:03 AM
Quote from: Nutz on 07 February 2010, 07:25 PM
Be careful when ordering o-rings. Early K-Jet versions used a round o-ring and later K Jet models used a squared o-ring.
Which O-Rings changed, was it the eight that connect the metering slits to cast iron body ?
I ask because I have a spare fuel distributor I was going to attempt a rebuild of.
koan
The single base O-ring.
Do all fuel distributors seal to the metering flap assembly the same way? Do some have an O-Ring sandwiched between the parts and some have an O-Ring around the fuel distributor base that sits in the metering flap base - hence the difference in O-Rings?
I'm camera-less at the moment so can't do pictures but the O-Rings associated with the metering slots sit on shaped protrusions around the metering barrel. They could be held with a sleeve if necessary during assembly. There is picture showing the protrusions in link I posted above.
There does appear to be a very thin coating of sealant on the mating surfaces. The discolouration on both sides of the shim will clean off with carb cleaner leaving an even shiny surface, I think that is the sealant. It also cleans off the top and bottom halves but not as obviously.
The link I posted earlier mentions using "Permatex Indian Head Shellac" between the cast halves and the shim. I saw it on the shelf at the local Burson Auto Parts so I bought a bottle. Expected a very thin liquid but it's not much different to the usual Permatex gasket goo.
I don't think I'll end up using it as it will be impossible to get an even coat, think I'll use a light spray of Hylomar on the surfaces after making up some round cardboard masks to keep the Hylomar from getting where I don't want it.
koan
koan, are you saying you can get gasket sealant in a spray can? Damn that must be useful.
Well, this is an interesting topic, right up my alley. 8)
I'm not sure about the variance of the o-ring for the base of the fuel distributors. I have not seen any reference of come across any variation on the round profile single o-ring, even on the W126s.
Nutz, are you sure it's not just that a round profile o-ring has swolen and taken the form of a square profile ring over time? If this is not the case, then my apologies and I stand to be corrected.
Could someone kingly enlighten me on this difference, ie. with a picture of some sort. :)
The o-rings inside the unit are easily to work with, as the hold thier position without trouble.
A very interesting point is that there is NO gasket material used from the factory. It is merely a very tight tolerance between the machining of the halves and the metal diaphragm sheet between. I can't imagine that it would even leak after a tear down and rebuild, so I would prefer not to use the gasket material if possible.
Tim
Quote from: TJ 450 on 08 February 2010, 08:03 AM
Nutz, are you sure it's not just that a round profile o-ring has swolen and taken the form of a square profile ring over time? If this is not the case, then my apologies and I stand to be corrected.
Could someone kingly enlighten me on this difference, ie. with a picture of some sort. :)
Tim
Example I dug up, but of course shallower.
(http://www.balleracing.com/Hayes/HayesBanjoO-ring.jpg)
Gee, that does indeed look like a square cross section.
Quote from: s class on 08 February 2010, 06:50 AM
koan, are you saying you can get gasket sealant in a spray can? Damn that must be useful.
Yes, do a search for Hylomar and see it in cans. Expensive and a can doesn't go very far - but maybe I put too much on.
koan
Well I talked to Larry Fletcher at CIS Flow Tech. The guy is full of knowledge! He said he would only trust 2 other guys in the world to rebuild these besides himself. Some guy in England and another in Australia. I inquired about the Australian guy for everyone here that is down under. Here is the information he gave me.
Peter Bower
bowerpower@bigpond.com
Bower Power Auto Tech in Sydney
phone 61294530035
He also said I probably do not have a bad fuel distributor but wants my mechanic to check my air flow sensor plate rest postion and sent me the following pdf.
sensor plate (http://img695.imageshack.us/img695/1923/78slsensorplatee.pdf)
Did some internet digging
Bower Power Auto Tech
3B Cook Street, Forestville NSW 2087
T 02 9453 0035
F 02 9453 0038
bowerpowerautotech@bigpond.com
Thankyou for going to the trouble of providing that address Zedster.
Bill
Larry also pointed out to me that my sensor plate zero position was too high. I measured it and it was 3.5 mm too high and the tolerance is only .5 mm. I adjusted it and it made a big difference. If you think through how the system works if the sensor plate zero or rest position is off your entire air/fuel is going to be off through the range. You can adjust the idle CO and control pressures all you want and the engine will still be too lean or too rich in places.
How do I know this? I replaced everything in the fuel system except the air metering housing and throttle plate but the car still didn't run right. I've know about that throttle plate spec and adjustment for a long time but I did not really understand the criticality until Larry stressed it to me.
WUR stands for Warm Up Regulator which is a misnomer. It controls your air fuel mixture throughout the range and can be thought of as the brains of your CIS system although it is crude by modern standards. It also manages the warm up cycle but that is actually a small part of what it does. It's my personal belief that the vast majority of Mercedes CIS systems are not setup and calibrated correctly.
Just the 6.9's have the WUR right?
All K-Jetronic cars have a WUR or Control Pressure Regulator. It is the "roughly box-shaped" device with two fuel lines, an electrical connector and two vacuum connections terminating at it. It is positioned at the front of the engine on the RHS, relative to the driver.
Tim
Mine have K Jet? 79 450SEL
Quote from: etmerritt33 on 08 February 2010, 06:18 PM
If you think through how the system works if the sensor plate zero or rest position is off your entire air/fuel is going to be off through the range. You can adjust the idle CO and control pressures all you want and the engine will still be too lean or too rich in places.
K-Jetronic rest position is a visual adjustment and what I've read about it from practical sources it isn't all that critical. If it is a fraction high, provided it pulls down when cranked hot (high control pressure) it's not a problem. if the plate is too low though, it does need correcting.
I can't agree with your analysis of the effects of sensor plate rest position. Provided it pulls down as described above it will be OK.
What difference does it make where the sensor plate is with engine off?
koan
Is suppose this is heading towards an off topic debate, but I have not read anywhere about the rest position, only ensuring that the plate is centralised.
Actually, I originally thought that the mixture screw adjusted the rest position, but was told otherwise.
Perhaps it's time I pulled apart an airflow meter to sus it out. ;)
Despite what some people have said, the plate will always deflect downwards with the engine running, even when idling. 8)
The square section o-ring is interesting. I have no idea what fuel distributor that would fit.
Tim
All I know is that I mentioned to Larry that my car runs good but when I come up to a stop sign apply the brakes it will sometimes die from low idle. Not always. It will not turn over until the third key crank. My mechanic says he wants to replace the fuel distributor. Larry said, "I'm gonna make your day! Your problem is more than likely the rest position of the air flow sensor."
Any of you that think the sensor plate rest position is not critical are DEAD WRONG!. If you consider how the air intake funnel is shaped it is engineered that way for a reason. That reason is each one of those graduations and the position of the sensor plate is mechanically tied to the position of the plunger in the fuel distributor and that establishes your air/fuel ratio. If that relationship is off even by a little (.5 mm is the factory tolerance) the air fuel mixture will be out of sync based on air flow with the demands of the engine and the car will never run right. Will it run? Yes! But, it will not run as intended by MB. You will be too lean or too rich under different driving conditions and there is no idle CO adjustment or control pressure adjustment that will put things right.
How do I know this? I also thought at one time that the adjustment was not critical so I didn't pay enough attention until Larry Fletcher stressed it to me. I change WUR's and control pressures like most people change underware and I've also had a number of the Unwired Tools WUR's and have the latest one on my 6.9 that allows the control pressures and engine vaccuum and warm up control pressure cycle to be precisely adjusted via a laptop. I've adjusted the hell out of my system and replaced almost all the components. Lowering that rest position for the sensor plate made a big seat of the pants difference because mine was 3.5 mm too high. The improvement you realize is directly related to how far off the rest position is for the sensor plate.
Trust me on this one. If you don't you will be leaving some nice improvement with respect to driveability on the table.
Also, the comment about the air sensor plate always being down when the car is idling is also incorrect. I also thought that to be true until recently. During the warm up cycle when the auxiliary air valve is open and the control pressure is low to richen the mixture, the air sensor plate will deflect noticeably, perhaps 2/3 to3/4 of an inch. After the engine warms up and the auxiliary air valve closes and the control pressure rises, the air sensor plate will only deflect very slightly at idle. If you do not believe this pull the air cleaner housing off and observe this for yourself. This does assume that all the components in your fuel system are working correctly.
I, like most people, learned these things over time as it is human nature to not begin the process by studying and understanding how the system was engineered before touching it. So, I've had to delve into different aspects of the system as problems have occurred and learn the surrounding components. I'm still not sure I know everything about it as every time I think that, someone more experienced teaches me something that I did not know. I do know this. I know a hell of a lot more about K-Jet than I did when I started the 6.9 sorting over 5 years ago now. I admit I'm a pretty slow learner.
Hope this helps.
Great info etmerritt33! I sent the pdf to my mechanic and he hasn't responded to me yet. I hope to get mine working properly.
That sounds very reasonable, etmerritt33.
Regarding the deflection, that is what I mean in my previous post.
Maybe this is the problem I'm having with my 6.9, as I paid no attention to the rest position when I pulled apart the airflow meter. It has run very lean ever since. I can't drive it until I fix it because when it warms up, it pings like crazy... the last thing I want is to have to deal with is major engine damage.
Tim
Quote from: etmerritt33 on 09 February 2010, 05:40 PM
Any of you that think the sensor plate rest position is not critical are DEAD WRONG!. If you consider how the air intake funnel is shaped it is engineered that way for a reason...
I'm going to be quite dogmatic about this because your explanation doesn't hold up.
It matters not one iota where the sensor plate sits when the engine is not running. What does matter is where the sensor plate sits in the funnel when the engine
IS running.
The position of the sensor plate when running is determined by airflow and control pressure, not it's rest position.
The idle mixture is adjusted with the engine running and once that's set the mixtures at various throttle openings and engine RPM are determined by funnel shape and control pressure (which includes vacuum controlled enrichment applied to the warm up regulator) and that's it, there is nothing else to adjust. Rest position of the sensor plate doesn't come into it.
The only danger is if the sensor plate is too high is that it might not pull down when cranking. If your sensor plate was way too high this might have been the cause of stalling at lights but it won't affect running under open throttle.
"TJ 450", Have a look in the Library at a 450 SEL (which uses the same fuel distributor and air meter as 6.9) Job 00-245, "Replacing, centering of air flow sensor plate, checking and adjusting of zero position of air flow sensor plate.
Agree with you TJ regarding sensor plate deflection at idle
I've followed your trials and tribulations on m-100.cc, I may have contributed when you were given inaccurate information by another poster.
You say you "change WURs like underwear" or "adjusted the hell out of your system", that's suggest to me there is something wrong somewhere, have you replaced the fuel distributor itself?
Also puzzled about the linking of aux air valve to control pressure, they operate independently, there is no connection between them, it's just that they operate simultaneously as the engine warms up.
I'm always a bit concerned when authorities are quoted and there appears to be holes in the argument. I'm always willing to be corrected with rational argument though.
We are all going to have to learn more about our aging machines and work in the areas we wouldn't have delved into before because there are fewer and fewer capable people around.
At the moment I'm collecting fuel distributors and pondering the effects of age on the springs in the flow equalising chambers, how they might affect the mixture under various operating conditions.
Please "etmerritt33" have a think about the way I believe it works and point out where the flaw is.
koan
Job 00-245 where is that?
Thanks Koan, I'll have a good look at the manual.
Tim
Quote from: zedster on 10 February 2010, 03:03 AM
Job 00-245 where is that?
Sorry, error on my part, in the library but it's "Engine Manual", 07.3-245.
koan
Koan,
I stand by everything I said and have no real interest in arguing with you. It's all in the manuals. Just to be clear I have a brand new aluminum fuel distributor, two new WUR's (Bosch and UT), all new bronze fuel injectors, new fuel damper, new fuel pump, and new auxilary air valve. You adjust the rest or zero position of the air sensor plate by pressurizing the system and with the engine OFF! I was just trying to share some info with you guys that I have learned the hard way so you could avoid some of the frustration I've gone through. If you refuse to believe that the rest position of the air sensor plate matters that's fine with me.
- Tom ;)
Tom, I believe you and will pass this info on to my mechanic. koan, I also respect your knowledge on these cars. I bought a new fuel distributor yesterday from AutohausAZ. Larry called me today just check to see if I had gotten it squared away (what a guy!). I told him I bought a new one (one of his) and would keep him posted.
Quote from: zedster on 11 February 2010, 07:23 PM
I bought a new fuel distributor yesterday from AutohausAZ.
Nice, is it alloy or cast iron? And it is actually new or a rebuilt unit?
On related (!) matters, there's too much voodoo and black magic surrounding our cars. I particularly fire up when I read the words "my mechanic said..." and what he says don't stand up to scrutiny. pretty common with fuel system and hydro suspension. All I want are logical and coherent explanations of how things work. Always willing to be corrected but only with rational argument.
koan
Agreed koan. In my opinion, when one has actually worked through a 6.9 suspension, one should have a proper understanding of it, and what follows is the realisation that it is actually pretty simple. I'd like to think the same is true of K-jet - but I think though that the initial learning curve of getting to grips with it is steeper.
Mine is the cast iron part # 0438100012
FD29X Rebuilt Fuel Distributor
Bill
Quote from: zedster on 12 February 2010, 01:50 PM
Mine is the cast iron part # 0438100012
FD29X Rebuilt Fuel Distributor
Let us know how it goes. I'm thinking I might be in the market for one.
I'll try a rebuild of my spare, I have some ideas, if it doesn't work out I might have to spend money.
koan
Ya the price wasn't too bad. $509 shipped and I get $120 back when I send back the core.
The Fuel Distributor has been replaced and wow what a difference! Only problem now is cold start and yes you all guessed it: WUR (Warm Up Regulator) Anyone know the part number for a '79 450 SEL? This will be my next purchase. :)
Bill