back to the infamous rich Djet operation

[Graham]

Originally Posted by meltedpanda

well I believe it is my triggers, if the 100 -120 is the magic number,
I made a jig to test roughly got the following

I have two sets, on one thay all stay open 180 +/-5
the other set 2 pair stay open 180 the other stay open 220 !!

now I need to see if I can adjust , just how, not sure .... suggestions, were you successful Graham?
perhaps the MPS is fine and all rich condition is strickly the points staying open too long

thoughts??

Regarding how to measure, from memory, I think middle contact is ground and you then need to connect other side of meter to each of the other terminals in turn. I rotated the rotor slowly and noted where the points opened in closed based on the ohmmeter needle movement.

Regarding adjustment, I also had two sets, so did try adjusting one set. At first thought I might be able to squish the fork plate in a vice, but that was imprecise and I could not get much improvement. I then tried bending the pieces shown in the picture below. But that takes a lot of trial and error, so I gave up. The other used set I had bought were fine. I have a new set, but haven't bothered installing them yet.

You may have read that Bosch are about to release a repair kit. It sounds to me like it will include new points and the wires will require soldering. Tom Hanson at Classic Centre will likely know about these or Bosch USA.

[meltedpanda]

thanks, I had two set the one I tried the bend idea and I got it to work on three of them but not the 4th - too far gone. On the set that was newer, realizing , I could bend and by trial and error get them to stay closed shoter time, I was able to get all 4 right around closer for 120 degrees, one was at 125-30, It was the best I could do. I then reinstalled, pegged the dizzy CCW to full stop ( where it was) moved the ecu to center point and fired her up - she started fine, play a bit with the AAV cold to stop hunt, then she purred - I was amazed, droped from high idle to 800 hot , a little miss ( may be something else) and move the ecu to 3 clicks to rich , before it needed to be full rich to run. I did not have time to test with sniffer but will do tomorrow, I still may need to play with MPS, but what I did today definetly set it on a better course.
Tomorrow will be another day, I really think by this that my triggers are the issue
When is the release date for the repair kit??

[Graham]

Originally Posted by meltedpanda

thanks, I had two set the one I tried the bend idea and I got it to work on three of them but not the 4th - too far gone. On the set that was newer, realizing , I could bend and by trial and error get them to stay closed shoter time, I was able to get all 4 right around closer for 120 degrees, one was at 125-30, It was the best I could do. I then reinstalled, pegged the dizzy CCW to full stop ( where it was) moved the ecu to center point and fired her up - she started fine, play a bit with the AAV cold to stop hunt, then she purred - I was amazed, droped from high idle to 800 hot , a little miss ( may be something else) and move the ecu to 3 clicks to rich , before it needed to be full rich to run. I did not have time to test with sniffer but will do tomorrow, I still may need to play with MPS, but what I did today definetly set it on a better course.
Tomorrow will be another day, I really think by this that my triggers are the issue
When is the release date for the repair kit??

From this, seems like March:

http://www.automotive-tradition.de/en/start/index.htm

From this months update:

Available in short time: Workshop repair kit for D-Jetronic pulse generator

At the moment, Bosch Automotive Tradition is producing a workshop suitable repair kit for the D-Jetronic pulse generator in close corporation with Mercedes-Benz Classic Center. The parts set is applicable for two different part numbers (MB A 000 158 01 19 --> RB 1 230 090 009 und MB A 000 158 03 19 --> RB 1 230 090 013) and the solution for torned pulse generators in vehicles from Mercedes-Benz of the following types: W116, W111, W108/109 as well as R107 with 8-cylinder-engine and D-Jetronic. The repair kit will be available from March 2011.

BTW - on the vintage forum, Werminghausen said he was going to try using VW trigger points which apparently can be obtained - I know nothing about them though.

[meltedpanda]

short lived happiness, it is better, with the trigger point adjustment but not much
the poor lumpy idle and rich running remians, just to a lesser extent. off Idle she pulls like a freight train and runs well. I am tempted to play with MPS, but really think the trouble lies in my trigger points. What else would make her run rich in full range??
I have been able to back ecu to 6 clicks to lean, before she was only running on full to rich. Not even sure that makes sense. My sniffer seems irradic, I can watch the needle move from lean readings to rich at idle, not sure why

GGR , how easy is easy on the megasquirt route?
PM me your email, love to chat...

My goal is to drive this ol gal a lot this summer, did the concours thing,thats over, now just want to drive, without a lot of hassle,and not smell like hydrocarbons after I am done lol
I am open to ideas let em rip..

[Gurunutkins]

HI Ron
I'm home for a few days - sounds like you are having fun!
if you stick a vacuum gauge on the manifold what type of vacuum are you running at idle?
cheers
Barri

[GGR]

Sorry for a short thread hijack, bur related to Barri's question:

Barri, I fitted that 5.0 with Megasquirt as you know. I have AMG camshafts which are a bit more aggressive. My advance at 650 rpm idle is around 4 degrees BTDC and my vacuum shows 50 kpa on the MS screen gage. They say I should tune the VE table at idle so that I have the lowest kpa reading but I wasn't able to go lower than that. I have no vacuum leak (engine stalls when I screw in the idle adjustment) and no blow-by. Is this OK or is there something wrong I should try correcting?

[GGR]

Originally Posted by meltedpanda

GGR , how easy is easy on the megasquirt route?

I am open to ideas let em rip..

Well, it's good that Barri shimmed in because he has more experience than me with MS on the M117.

MS requires a lot of reading, a bit of modifications and depending on the install can cost from $500 to $1000 to set up.

Let me put it like this: if you just want to sort out your current problem and enjoy your car this summer then you're better off trying to sort out the current D-jet issue you have. It will be quicker and cheaper.

If you want a project, get into knowing better how your engine works and have the possibility to tune it much better for performance and/or mpg, while saving some money on the long run as replacing failing D-jet elements won't be cheap, then you should consider Megasquirt.

How easy it is? It depends on how complicated you make it! You can build your controller or buy it all assembled. You can go fuel only, or fuel and spark. You can keep as much D-jet hardware as you can, or replace some of it with elements better suited to MS (smaller injectors, vacuum actuated FPR, relocating Air temp sensor in the plenum, etc.)

If I remember well, Barri kept as much of the D-jet hardware he could, while I went a bit further in the modifications. But I have less experience than Barri as I am still unable to drive my car at the moment (a clutch problem).

All in all, the D-jet system makes the conversion easy as it is already an EFI system and you can keep most of the hardware in place. Converting Kjet system is more involved.

I sent you my email via pm.

[Gurunutkins]

Originally Posted by GGR

Sorry for a short thread hijack, bur related to Barri's question:

Barri, I fitted that 5.0 with Megasquirt as you know. I have AMG camshafts which are a bit more aggressive. My advance at 650 rpm idle is around 4 degrees BTDC and my vacuum shows 50 kpa on the MS screen gage. They say I should tune the VE table at idle so that I have the lowest kpa reading but I wasn't able to go lower than that. I have no vacuum leak (engine stalls when I screw in the idle adjustment) and no blow-by. Is this OK or is there something wrong I should try correcting?

Hi Gael
sounds about right to me. a more aggressive cam with "big" times will reduce the vacuum significantly - a full race engine will only have about 2 to 3 inches at idle. I would try to tune as it is. Also on the LS 1 problem I will be heading to the track tomorrow evening and I will ask. did some checking this weekend and it sounds like you will have to clear the bubble memory on the control unit.
cheers
Barri

[Graham]

Originally Posted by GGR

Sorry for a short thread hijack, bur related to Barri's question:

Barri, I fitted that 5.0 with Megasquirt as you know. I have AMG camshafts which are a bit more aggressive. My advance at 650 rpm idle is around 4 degrees BTDC and my vacuum shows 50 kpa on the MS screen gage. They say I should tune the VE table at idle so that I have the lowest kpa reading but I wasn't able to go lower than that. I have no vacuum leak (engine stalls when I screw in the idle adjustment) and no blow-by. Is this OK or is there something wrong I should try correcting?

Gael,
Where does the MS pick up the vac reading?

On my d-jet, I know I get different readings depending on where I hook up the gauge. Best I have seen is about 18inHg, but normally I read 16inHg off back of intake manifold which is about 54kpa, I think. Depends on timing setting.

Ron - I think Gael summarized conversion to MS well. I suspect you are in same boat as me - Just want car to drive well. It's hard to know at a distance what is wrong with your car. But a reliable exhaust analyzer is a must. I found that the ones that go in tail pipe don't work properly - outside air gets back-mixed (I ended up trying blocking one pipe and measuring in the other. In the end, I only achieved good results by installing the full time wideband AFR gauge (AEM or Innovate for $200 plus installation). You may have a problem with the trigger points still, but maybe your MPS is bad or incorrectly set? The ECU mixture adjustment only affects idle. Need to get the overall mixture right first. Try adjusting MPS by trial and error - just lean it out 1/8 turn at a time (which way to turn? I forget!), go for drive, and do it again and see if you can get exhaust to look clean. You might also check that the cold start valve is not leaking.

[meltedpanda]

will do guys, I run 16-18 inhg so my vacuum is good and no leaks, I am considering all of the above. I will continue to play with my current components and see what happens
May even spring for TP, since I know it is part of the issue.
Genbiltstien has a MPS off a 74 , gonna see if that is compatible with my 72 , anyone know - is Djet - Djet ??

[Graham]

Originally Posted by meltedpanda

will do guys, I run 16-18 inhg so my vacuum is good and no leaks, I am considering all of the above. I will continue to play with my current components and see what happens
May even spring for TP, since I know it is part of the issue.
Genbiltstien has a MPS off a 74 , gonna see if that is compatible with my 72 , anyone know - is Djet - Djet ??

Ron,
Give Tom Hanson at Classic Center a call re TP repair kits. They should have them soon. Or email him at thomas.hanson@mbusa.com.

Regarding the MPS, it should have a number on it. Bosch number was 0280100100 and MB number 002 542 28 17. I don't think they changed until 1975 model year. There do seem to be two versions. Maybe someone will loan you a spare one for a trial? (I have one, but the hassle of shipping across border makes in impractical.)

[meltedpanda]

hey gang, was reminded, I need to rule out cold start injector for leakage,
what is best way here , I know it is working because even in cold ( over winter ) she fires up fine, I never really have a cold or hot start issue, but I guess it could be leaking for the rich condition
I cant find an easy technique for test on the car , it seems I could remove and crank a cold enigne , it should spray and shut off ?
Or do I have to remove
Anyone care to share how they tested?

[Gurunutkins]

grab an old piece of inner tube or rubber mat and wrap it around the short bit of supply pipe to the CSI - then clamp that with a pair of mole grips to stop the supply to the injector. The rubber should protect the supply pipe. start the car and see how she runs.
cheers
Barri

[Graham]

Originally Posted by Gurunutkins

grab an old piece of inner tube or rubber mat and wrap it around the short bit of supply pipe to the CSI - then clamp that with a pair of mole grips to stop the supply to the injector. The rubber should protect the supply pipe. start the car and see how she runs.
cheers
Barri

That should work.

Manual section 7.4.1 11-125/3 does give two methods, one for when hot and one for below 35C. All you have to do when cold, is remove the valve with hose attached and direct it into a container. Turn ignition on and it should spray. Turn ignition off and there should be no drips from the valve.

[meltedpanda]

turn the ignition as in to the "on" when fuel pump runs or crank it and run engine?