Some of the FI distributors are slightly different in timing. The length of open injection firing winow is like 165-170*. Then the cam moves on to the next bank. Just marking one dizzy and dropping in another will not set your timing. It will be off. Also, did you check that that the drive dog of the new dizzy is oriented the same as the old? You could very well have a type 3 dizzy....instead of a type 4. They are idnetical except the timing is about 90* different...because the vacuum can sits in a different spot on type 3 when installed. This is ccommon with rebuilders. They do not know the difference. They basically suck...every one of them. You did mention that you have occasional "bangs" in the manifold? This..and the stalling...WILL happen if you are 90* out of time. Also...it sounds like your trigger points are junk. What is their individual resistance reading per side....plug disconnected?
Bear this in mind. If one injector fired...but the other one hooked to this pair did not, then you simply have a bad wire to the non firing injector, a bad plug, or a bad ground on that injector pair.
If you have a pair that will not fire at all...its about a 100% chance that the cam is not opening that trigger set on that side. You have two triggers...180* apart. They have seperate cam followers. If one is worn..or one is bent....it will not touch the cam. Also, when you have this apart, reach in with a screwdriver...or pencil eraser and see if the triger cam can be "jiggled" from side to side on the dizzy shaft. If it can...it is totally shot. At that point...dump the whole dizzy in the trash..and start over. What is the distributor part # on the rebuilt dizzy?
It sounds like you got a mis-numbered type 3 POS from wherever you bought it. The first and last rebuild I got was like this. I went bacck and thew the disassembled pieces up on the counter...and told them they just lost about $7000 a year in business. Never went back.
Here is a real simple test. Take a spare set of trigger points. Plug the 3 wire plug into them while they are out of the dizzy. Disconnect your coil so you don't light yourself on fire. Pull all four of your injectors out of the bores in the runners. Place a rag under each tip. Turn the key on...leave the engine off. With your finger...open the right hand contact set. You will see and hear two injectors fire. Then do the other one. If all four injectors fired after you cycled each trigger...you just found out that there is nothing wrong with your entire system...except for the triggers in the dizzy...or their riders on the cam....which is what it is from your descriptions. If one injector in a pair fired only.....check your wiring from teh grounds to the injector plugs to the ECU. Ray
Engine Rebuild? What went wrong????
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vwbill
- Posts: 970
- Joined: Sat Feb 15, 2003 12:01 am
Rebuild rebuild,lol!
Hey Ray, pulled the rebuild dist. The FI points on it seem good. I dont get it but the lower shaft must be from the T3 like the numbers on the case said so when they said they chk the cam and set it all to T4 412 Specs like the vacuum can, the point plate,ect. That was BS! The rebuild has a cam that fires(closed circuit) one for 180 degrees for term 21(left) for rotor position 1 thru 3(clockwise) . The other term 22(right) fires for like 330 degrees starting after the rotor passes the number 1 position by 30degrees. Maybe that is right for a 1600 D-jet? On my old one it fires(closes)for 180degrees for term 21 and 22. My Question now is which term(21-left,22-right) on the FI points should be firing when the rotor points at the dist body at the 5 o'clock position at TDC? I think I have my top shaft 180 off?! I have term 22(right) firing for 180 degrees when the rotor is at the number 3 position(12 o'clock)for the rotor. Then term 21 fires for 180 degrees starting from the number 1 position or 5 o'clock. Can I just switch the wires in the FI point connector so 21 is at 22?
I gave current to the aux air regulator and it didnt change the air flow!
How long do you have to give it current? It is connected to the fuel pump relay since it will make the pump run! I'll try and use some noggin to figure out when the FI points should fire for 180. I should video all my work so I can go back and see my disassemble! Thx Bill
I gave current to the aux air regulator and it didnt change the air flow!
How long do you have to give it current? It is connected to the fuel pump relay since it will make the pump run! I'll try and use some noggin to figure out when the FI points should fire for 180. I should video all my work so I can go back and see my disassemble! Thx Bill
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vwbill
- Posts: 970
- Joined: Sat Feb 15, 2003 12:01 am
Run Run
Hey, toke my original dist. and turned the top shaft so the rotor faced the 5 o'clock position at TDC. Installed it at the same place the points came on when I toke out the so called rebuilt one and put the original Dist. in and set it so the points just came on. Connected all the hoses and wires.
Turn the key and she started instantly!!!!! Yeah!!!!!!! I hate rebuilds!!
I must have been out of it when I checked that one!! I must have wanted it to be right so I thought it was!! LOL! Now I need to fix my number two exhaust leak! I hate those heat exchangers sometimes!
Need to cast out a copper top that fits over the top of the tubes that meet the heads or "U" shaped pliable copper so it doesn't fall off or miss align!
Well I hope it still runs tomorrow morning,lol!
Thx Bill
p.s. Funny thing is I think it ran with that dist. at some point????
Hey I chk two other FI dist cams and they were both different so do the bottom shafts have to match the ECU? How do you get the curve recut on the bottom shaft?
Turn the key and she started instantly!!!!! Yeah!!!!!!! I hate rebuilds!!
I must have been out of it when I checked that one!! I must have wanted it to be right so I thought it was!! LOL! Now I need to fix my number two exhaust leak! I hate those heat exchangers sometimes!
Need to cast out a copper top that fits over the top of the tubes that meet the heads or "U" shaped pliable copper so it doesn't fall off or miss align!
Well I hope it still runs tomorrow morning,lol!
Thx Bill
p.s. Funny thing is I think it ran with that dist. at some point????
Hey I chk two other FI dist cams and they were both different so do the bottom shafts have to match the ECU? How do you get the curve recut on the bottom shaft?
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raygreenwood
- Posts: 11913
- Joined: Wed Jan 22, 2003 12:01 am
The guts, FI trigger cams and everything in the whole system..including injector firing order...are the same on type 3 and 4 D-jet. So are the trigger point parts #'s. The diference in the type 3 and 4 dizzy...is simply this.....because the of the vacuum can....the type 3 dizzy has the vacuum can at about 11:00 position if memory serves. On the 412....its about 4:00. So if you take a type 3 dizzy body and drop it into the type 4, the distributor cam will be in a different location than in the type 4...in relation to the ignition firing order....AND your firing order will be off in ignition. I can't remember...butI think its actually 180* out. Yep...it must be..ecause you can make a type 3 dizzy work in a type 4. If memory serves....you need to take the pin out of the drive dog....and flip it 180*.
Now...think about this.....if the new dizzy ran a little and fired all injectors, then chances are either the trigger cam was slightlyworn...or the FI trigger points on the offending side were slightly worn....or thr triggers are bent. That means that they are borderline. No amount of looking at them will tell you if they are right. The proper measurement for triggers..between the rubbing blocks...is .923" give or take .005". Problem is...if the rubbing blocks are new...as they frequently are on rebuilds....and the gap is off.....you will need a factory jig to bend the angle right. They are very specific. Maybe in a couple months I can make a cheapy. Save the triggers. Ray
Now...think about this.....if the new dizzy ran a little and fired all injectors, then chances are either the trigger cam was slightlyworn...or the FI trigger points on the offending side were slightly worn....or thr triggers are bent. That means that they are borderline. No amount of looking at them will tell you if they are right. The proper measurement for triggers..between the rubbing blocks...is .923" give or take .005". Problem is...if the rubbing blocks are new...as they frequently are on rebuilds....and the gap is off.....you will need a factory jig to bend the angle right. They are very specific. Maybe in a couple months I can make a cheapy. Save the triggers. Ray
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vwbill
- Posts: 970
- Joined: Sat Feb 15, 2003 12:01 am
Why do you need them?
Hey why do they use points to fire the injectors on D-jet and not for the L-jet? How does the L-jet set the Basic flow rate and timing? I have the TDC sensor? Could you use one of those pickups you strap to the shaft to open and close the circuit? Like for a cruize control with magnets.
I want to add a memory with a LCD to show how the MPS is reading when running. What is the adjustment range that the MPS makes to the Basic flow rate? Is there a why to add limiters to the MPS wires to control and fine tune the change it makes or is that what the knob on the ECU does basically? I would like to see the motor running on a oscope to see the mixture and injection firing to ignition timing. I guess that is what you do by getting all the parts to work right. Bill
I want to add a memory with a LCD to show how the MPS is reading when running. What is the adjustment range that the MPS makes to the Basic flow rate? Is there a why to add limiters to the MPS wires to control and fine tune the change it makes or is that what the knob on the ECU does basically? I would like to see the motor running on a oscope to see the mixture and injection firing to ignition timing. I guess that is what you do by getting all the parts to work right. Bill
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raygreenwood
- Posts: 11913
- Joined: Wed Jan 22, 2003 12:01 am
Why do they use triggers? Well....bear in mind that it is the first production electronic injection system...circa 1966. Theye didn't have many other things....if any, capable of switching that fast.
this is one of the reasons why I like to play with D-jet. Its a museum piece. I will modify it a lot...but basically keep mine intact. I like old stuff. Its a marvel of design.
L-jet, seems a bit more sophisticated inside...but not really. It simply fires all four injectors at once. L-jet also uses different metering. I belive L-jet is less accurate than D-jet. Actually it probably is more accurate...but certainly less adjustable than D-jet.
You will find it very hard to beat the triggers. First, the triggers fire when they are opened, not closed. Not a hard thing to get, but an optical switch unit would work best...or a normally closed position magnetic switch like a pertronix. Putting it all into the dizzy body would be tough and getting it to work right.
Most people...cite D, L, CIS, digifant...and a slew of other injection types, as showing that perfectly timed sequential injection of fuel is not necessary. Actually, I think it is necessary to get the very best out of a system...but just not imperitive for good basic running. It mainly appears that "banked" or grouped injection of fuel like all of those systems above (and most if not all on the market) use, were done so for simplicity and affordability.
D-jet can be made sequential...without duplicating the ECU circuits. I have made a new trigger set...that I will drop in and try once I have my new engine together and well broken in.
I already know it works well. I just have not driven with it...so I do not knowwhat difference it will show. I DO know that you can see what timing changes to existing D-jet will do right now...by loosening the trigger plate...slotting the screw holes...and moving it while the engine is running. It is very significant.
The new triggers I made are very small. There are 8 of them. 4 "on" triggers...and 4 "off" triggers. The cams are less than 1/8" thick, are made of Torlon (slicker than teflon, harder than Delrin...600+ degree plastic). They are sandwiched together, set screwed to the dizzy shaft and are adjustable in reference to each other wih a slotted lock screw throgh the 4 of them. The four off switches simply break the four injector grounds....or connect them when that injector is to be "open windowed". The main cam on top has the same time sequence of open as stock. Same # of degrees for each open window and the same time at distributor speed. So the ECU still see's circuit 1 or 2 open, alternately ...at the same speed...as it did with original triggers. It uses the same original two injector circuits. The tricky part I have been playing with, is an advance method. I believe...cause the math tells me so...that the injection timing will have to advance just like ignition, as the rpm rises, to complete the injection of fuel, while the valve is still open. I made a linear weight type centrifugal advance plate on the top trigger cam...which is sandwhich bolted to the other three. It works really well from rpm testing. It fits inside either a stock unit, or a Mallory. We'll see hw it works around christmas...if all goes well. Ray
this is one of the reasons why I like to play with D-jet. Its a museum piece. I will modify it a lot...but basically keep mine intact. I like old stuff. Its a marvel of design.
L-jet, seems a bit more sophisticated inside...but not really. It simply fires all four injectors at once. L-jet also uses different metering. I belive L-jet is less accurate than D-jet. Actually it probably is more accurate...but certainly less adjustable than D-jet.
You will find it very hard to beat the triggers. First, the triggers fire when they are opened, not closed. Not a hard thing to get, but an optical switch unit would work best...or a normally closed position magnetic switch like a pertronix. Putting it all into the dizzy body would be tough and getting it to work right.
Most people...cite D, L, CIS, digifant...and a slew of other injection types, as showing that perfectly timed sequential injection of fuel is not necessary. Actually, I think it is necessary to get the very best out of a system...but just not imperitive for good basic running. It mainly appears that "banked" or grouped injection of fuel like all of those systems above (and most if not all on the market) use, were done so for simplicity and affordability.
D-jet can be made sequential...without duplicating the ECU circuits. I have made a new trigger set...that I will drop in and try once I have my new engine together and well broken in.
I already know it works well. I just have not driven with it...so I do not knowwhat difference it will show. I DO know that you can see what timing changes to existing D-jet will do right now...by loosening the trigger plate...slotting the screw holes...and moving it while the engine is running. It is very significant.
The new triggers I made are very small. There are 8 of them. 4 "on" triggers...and 4 "off" triggers. The cams are less than 1/8" thick, are made of Torlon (slicker than teflon, harder than Delrin...600+ degree plastic). They are sandwiched together, set screwed to the dizzy shaft and are adjustable in reference to each other wih a slotted lock screw throgh the 4 of them. The four off switches simply break the four injector grounds....or connect them when that injector is to be "open windowed". The main cam on top has the same time sequence of open as stock. Same # of degrees for each open window and the same time at distributor speed. So the ECU still see's circuit 1 or 2 open, alternately ...at the same speed...as it did with original triggers. It uses the same original two injector circuits. The tricky part I have been playing with, is an advance method. I believe...cause the math tells me so...that the injection timing will have to advance just like ignition, as the rpm rises, to complete the injection of fuel, while the valve is still open. I made a linear weight type centrifugal advance plate on the top trigger cam...which is sandwhich bolted to the other three. It works really well from rpm testing. It fits inside either a stock unit, or a Mallory. We'll see hw it works around christmas...if all goes well. Ray
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vwbill
- Posts: 970
- Joined: Sat Feb 15, 2003 12:01 am
It started again,lol!
Hey, thanks sounds sweet the point thing! I have been reading my Bentley "Bosch Fuel INj & Eng. Mgmnt" "understand,Service,modify" book.
Its nice to try to understand a little of the pulsed injection theory and the continuous injection theory! It seems like all the systems are adding or subtracting from some device to the ecu base line programming. Sometimes directly to the ECU or by changing airflow or density.
Seems like there is a sensor or adj for some condition of driving.
I like L-jet's Dist. for maintaining. It just seems funny using a system from the late 60's when "L-jet" from the "74" seems more in line with the late 412's. It's funny how when you can understand the principles of a system you get to see the good and bad of them. It's really like looking at the evolution of Bosch FI. Seems like the K-Lambda was popular.
Think about how many cars today have a fuel injection system. I like the D-jet for the word "Druck" I think I've said it a few times,lol!
Ok, is there a trick to getting a good seal at the heads and the heat exchangers? How am I creating a leak? Is it because the lip that the copper gasket sits in is hitting the tube and misaligning it or is it that I am hitting the gasket with the tube at a angle and casing the gasket to bow?
There is noway to look up there when the manifold in in place!
Once I get the exhaust and other leaks fixed, I'll reset everything, timing,dwell,ect...
Thx, Bill
Its nice to try to understand a little of the pulsed injection theory and the continuous injection theory! It seems like all the systems are adding or subtracting from some device to the ecu base line programming. Sometimes directly to the ECU or by changing airflow or density.
Seems like there is a sensor or adj for some condition of driving.
I like L-jet's Dist. for maintaining. It just seems funny using a system from the late 60's when "L-jet" from the "74" seems more in line with the late 412's. It's funny how when you can understand the principles of a system you get to see the good and bad of them. It's really like looking at the evolution of Bosch FI. Seems like the K-Lambda was popular.
Think about how many cars today have a fuel injection system. I like the D-jet for the word "Druck" I think I've said it a few times,lol!
Ok, is there a trick to getting a good seal at the heads and the heat exchangers? How am I creating a leak? Is it because the lip that the copper gasket sits in is hitting the tube and misaligning it or is it that I am hitting the gasket with the tube at a angle and casing the gasket to bow?
There is noway to look up there when the manifold in in place!
Once I get the exhaust and other leaks fixed, I'll reset everything, timing,dwell,ect...
Thx, Bill
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raygreenwood
- Posts: 11913
- Joined: Wed Jan 22, 2003 12:01 am
There are several ways to get the exhaust manifolds straight . First, Take them off. Put a straight edge across the tops of both flanges. Are they straight...or warped? If they are a little warped, you can bolt them to a plate and put a hil under the end of the higher one to keep it down and heat it with a torch. Them pop it in the oven and slowly cool it down. It should get straight enough to bolt up straight even if it warps a little later. Then take a flat bastard file and ...moving one direction only, lightly file the top of each one clean. Then, take a dremel tool withwire brush and clean the ledge where the copper goes very well.
The copper gaskets have a rounded edge sometimes and a flat edge. The flat edge goes against the head. Next...if you have not done it...replace all of the exhaust studs with course thread steel insets....NOT HELICOILS. Look at my past posts on this. Its not too hard even with the engine in.
Now....with the ledges clean...takes some superglue gel.....and put it on each end of the oval....just a very tiny drop.....on the edge only. NOT the flat area against the head. Hold it in place until it dries. Now you can bolt up the manifolds without moving the gaskets. Torque them by factory specs....USE ONLY THE 12MM COPPER EXHAUST NUTS!. They are available in most VW shops. Use antisieze compound on the threads of the nuts. Ray
The copper gaskets have a rounded edge sometimes and a flat edge. The flat edge goes against the head. Next...if you have not done it...replace all of the exhaust studs with course thread steel insets....NOT HELICOILS. Look at my past posts on this. Its not too hard even with the engine in.
Now....with the ledges clean...takes some superglue gel.....and put it on each end of the oval....just a very tiny drop.....on the edge only. NOT the flat area against the head. Hold it in place until it dries. Now you can bolt up the manifolds without moving the gaskets. Torque them by factory specs....USE ONLY THE 12MM COPPER EXHAUST NUTS!. They are available in most VW shops. Use antisieze compound on the threads of the nuts. Ray
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vwbill
- Posts: 970
- Joined: Sat Feb 15, 2003 12:01 am
Exhaust Leak?
Ok, I cleaned up the faces(filed) of the heat exchanger manifold tubes. I cleaned the gasket area and installed the copper oval gaskets and installed the Heat exchanger manifold. I start it and no difference in the exhaust leak sound! Arggg. lol. So I pull it and take a measurement from the copper gasket seat area with the gasket installed to the top of the exhaust stud mount towers on each manifold on the head and get 22mm using my Vern. caliper. I now measure the top of the heat exchanger tubes to the bottom of the stud hole ears on the tubes(the mount bracket) and get 22mm. Which means that the tube would just meet the copper gasket and top out since it would hit the stud towers on the head. So I file the exchanger bracket ear area down 1mm since the gasket is 2mm and then the tube would go to the middle of the gasket when installed and topping out on the tower. I install the again modified exchanger and start it and again I get the same exhaust leak sound!!
Like now I must be inept!!! I measured the tube to ears on my old pair of heat exchangers and I get 24.5mm. I want the tube ear area to meet the stud tower area so the manifold wont pier or pivot on the oval tube area?? So I cant just grind the ear areas down so there is like 26mm or more and the tubes just rest on the gasket area of the heads??
These manifolds were new installs too,lol! Does anyone know what that spec should be? I'm really thinking of just packing the tube area with exhaust patch compound and trying again!!! arggg! If I hear a leak sound again after installing the exchanger again I'm gonna weld them,lol!!! Not really! But Damn if it isnt the exchanger makin the noise there really isnt too many other places for a exhaust noise to be from i think! Top of the head and cylinder areas, heat exchangers to heads, exchangers to muffler and at the exhaust valve area of the heads.
Maybe I can do a half hour shop job in a year,lololol!!
thx, bill
Like now I must be inept!!! I measured the tube to ears on my old pair of heat exchangers and I get 24.5mm. I want the tube ear area to meet the stud tower area so the manifold wont pier or pivot on the oval tube area?? So I cant just grind the ear areas down so there is like 26mm or more and the tubes just rest on the gasket area of the heads??
These manifolds were new installs too,lol! Does anyone know what that spec should be? I'm really thinking of just packing the tube area with exhaust patch compound and trying again!!! arggg! If I hear a leak sound again after installing the exchanger again I'm gonna weld them,lol!!! Not really! But Damn if it isnt the exchanger makin the noise there really isnt too many other places for a exhaust noise to be from i think! Top of the head and cylinder areas, heat exchangers to heads, exchangers to muffler and at the exhaust valve area of the heads.
Maybe I can do a half hour shop job in a year,lololol!!
thx, bill
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raygreenwood
- Posts: 11913
- Joined: Wed Jan 22, 2003 12:01 am
Are you sure that there are no internal cracks inside the exchanger in the tubes. Also, could the cast steel flange on the tube be leaking at its joint to the tube?
Also...did you say these are new heat exhangers? The flange area should not touch the alumium of the head under the "ears". You may have to file a litttle more if it is hitting.
Also....if the exhasut studs have been replaced and they did not get them straight....the manifold will wedge onto thestuds and not go down all the way. Take a round file or dremel and clearence the stud holes in the manifold ears. Ray
Also...did you say these are new heat exhangers? The flange area should not touch the alumium of the head under the "ears". You may have to file a litttle more if it is hitting.
Also....if the exhasut studs have been replaced and they did not get them straight....the manifold will wedge onto thestuds and not go down all the way. Take a round file or dremel and clearence the stud holes in the manifold ears. Ray
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vwbill
- Posts: 970
- Joined: Sat Feb 15, 2003 12:01 am
Exhaust leak
Well I filed the flange ears down so they were at 24.5mm from the tube top of the exchanger flange ear. Same as the old ones. Remeasured the head to check the measurement from the oval gasket to the stud piers and still got 22mm from the pier to the oval gasket installed. Reinstalled the heat exchanger and the muffler. Start the car and still exhaust leaking sound!!! Arggg!! I get sound from the number two area of the exhaust manifold but cant get to hear it super loud in my test hose but can hear it. It sounds like the front(back of car) top left edge area of the exhaust flange to head for the number two cylinder. I dont hear it on top of the engine just the bottom. Why do I hear it in the middle area of the head exhaust port #2 and not down near the cylinder tin and the head edge! It has to be a head leak then what else could it be? No other choice! How can it be the exhaust manifold! I dont hear the leak on any of the tube areas just the #2 manifold head area! Well back to the listening and test mode! thx bill
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raygreenwood
- Posts: 11913
- Joined: Wed Jan 22, 2003 12:01 am
Just pull that head. Also, before you start all of that, look for another heat exchanger. Did you clearance the bolt holes in the one you have? Also have you checkedto see that the exhaust studs are parrallel and straight?
If these heads were rebuilt and any of the exhaust studs were replaced....there is a 90% chance they were installed crooked. That will keep the manifold from sealing. Most shops arelame in reapect to type 4 heads.
Hate to mention this...but this could also not be an exhaust leak. It could be a combustion chamber crack leaking into the exhaust manifold.
It can also be the actual muffler with a crack inside , it could be that cylinder running very elan or rich. Pull the injector plug and see if the sound on that cylinder changes. Ray
If these heads were rebuilt and any of the exhaust studs were replaced....there is a 90% chance they were installed crooked. That will keep the manifold from sealing. Most shops arelame in reapect to type 4 heads.
Hate to mention this...but this could also not be an exhaust leak. It could be a combustion chamber crack leaking into the exhaust manifold.
It can also be the actual muffler with a crack inside , it could be that cylinder running very elan or rich. Pull the injector plug and see if the sound on that cylinder changes. Ray
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Guest
head leak test
Hey, what if I take the exhaust manifold off and start the motor? Will I be able to hear if I still have a chuffing head/cylinder leak over the popping of the exhaust??? Maybe a way of telling???
Hey, you know what is weird about the exhaust leak sounds I'm getting,
it's that it happened after my first test drive after I was reving the motor to set the timing at the 3k rpm level just after a warm up and short drive it started to come on! I only drove it about a 1/2 3/4 mile. So my valves were a little out but not a ton; Could the heads just need to be re-torqued or is that just a dream! Still have to pull the intake to do that!
bill
Hey, you know what is weird about the exhaust leak sounds I'm getting,
it's that it happened after my first test drive after I was reving the motor to set the timing at the 3k rpm level just after a warm up and short drive it started to come on! I only drove it about a 1/2 3/4 mile. So my valves were a little out but not a ton; Could the heads just need to be re-torqued or is that just a dream! Still have to pull the intake to do that!
bill
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vwbill
- Posts: 970
- Joined: Sat Feb 15, 2003 12:01 am
Cylinder head
Hey is a bus 1700 the same as a 1700 T4 head? In the bus book it shows the same size valves? So then if I have a 021-101-371Q I can use the 022-101-361K also! More availablity new too!
Thx Bill
Thx Bill