New Car, Work done in July, August

I have been a bit remiss on posting new items, but, I have been busy working on the fuel rails drilling the holes, and polishing them, and some other miscellaneous items... Also trying to try the injectors, I pulled one off, and the hat, and spacer fell into the hole... So, not wanting a disastrous valve-piston contact, I took the intake manifold off, and replaced the gaskets... again. That was a minor set back. I also put the fuel rails and the passenger side one, fit perfectly, and you can remove the valve cover without removing the fuel rail... On the driver side due to the accelerator linkage it is rather tight, so this weekend I will take the driver's side fuel rail off, and have it ground down a bit so that there is at least some distance between it and the valve cover.

I also found out that the fuel lines use an M14 x1.5 tap, and will be making some adaptors with 1" square aluminum stock. As the fuel line needs to "stop" against something (otherwise it will never seal) I am planning on using a 2" long piece, on one side Will use the M14 tap (use a 1/2" drill bit) and drill to a 3/4" depth. On the other side I will drill for the 3/8NPT tap, and use a depth of 1"... that leaves me with a 1/4" shoulder that I can drill with a smaller 3/8" (8mm) hole, and this will provide the "seal" for the fuel line.

I still have lots of work cut out for me, and with the summer almost ending I will take some time this weekend to work and at least complete the fuel lines, and pressure test the system. I have the CIS testing equipment that goes all the way up to 100PSI, but with modern injectors you should never exceed 50.

We have also bought a 1987 W124 from an older gentleman's family, and after inspecting it, and taking it for a ride, it was in exceptional shape. here are some pics of the car:

So far we have replaced both headlight surroundings, buffed out the car (the white paint was chalky) and cleaned the interior. I have never seen my wife so excited with a car, and it is on the road, so we have been enjoying it. I have found some minor things that need attention, and have already bought the parts. I have ordered new rotors, pads, pad sensors, and a new heater valve ($95, and not $650 like some other W107 ones... I have the mechanical one, thanks the production year.. :-) ) So, there has been a lot of car work... Just not enough on the SLC!.

Injectors and electrical connectors

I have been working on getting the injectors ready by replacing the seals, the fuel injector baskets, and the fuel injector pintles (little plastic hats in the injector). I also tested them all and made sure that the resistance is about 14-15 ohms. They all tested within +/- .05 ohms... Not bad.
The fuel injector harnesses were built using fuel injector pigtails, and in parallel, and will use the 2 banks that Megasquirt can controll and alternate them. I also tested all the connectors as I do not want any surprises when I try to start it. I have also started the connectors for the clt, the iat, and the negative post of the coil. I will also wire the O2 sensor cable, and wrap it up for future installation after I have installed the shorty mustang headers (future project).
Tomorrow I expect to finish the basic cabling, and will start wrapping it up so that it looks nice and neat. The fuel Injectors are in the car, and I am waiting on the 14mm drill bits to make the final cuts in the fuel rails. Once that is done, I can assemble all the fuel injector components, including the FPR, and tie down the fuel injector harness and the sensor cables so that they are not all over the engine compartment.

Bad Wedding, Fuel Rail and Air slide valve hole cover

I have been busy cutting the fuel rails, and tapping them at the ends for 3/8NPT. So far all 4 are done, and the next step is to actually drill the holes for the injectors. I ordered a 14mm drill bit, and a 3/4 so that I could make all 3 cuts. The plan is to drill the first bit with the 3/8th drill bit all the way to the center, and then use the 14mm (correct size for Fuel Injectors) to make about a 1/2" deep cut where the injector actually sits in, and the 3/4" is to chanfer the angle at the start of the hole, so that the fuel injector seal is not torn open. I also need to hone and polish with my dremel the inside so that it is nice and smooth. Final touch will be to paint it in a nice satin black finish to contrast against the silver intake. Will look neat.
This weekend though was taken up going to a wedding, but I will start with the new cabling on Sunday. It should not take too long, as I have all the parts of where the cables go scoped out, and just need to run the cable, install the relay board in a place that will not get too wet under the hood, and then start the long process of figuring out what goes where. I am also going to run new power cables to the front lights so that I can relay them, and avoid overloading the 30 year old cabling, and switches.
My main concern right now is getting the exact length in between injectors so that they seal perfectly, and do not have fuel leaks, as that generally is a bad thing. I have also backordered 2 m14X1.5 female to AN6 male adaptors that will replace the lines coming in from the fuel pump right behind the booster, so no need to cut the original hoses and clamp them. It think that it is a far neater, and safer solution overall, and safety needs to be first.
The fuel system itself is designed with 300PSI hoses, connectors, and gaskets, even though the fuel pump will only get to 125 max, and is used to running at 75 for the CIS system.
As what creates the pressure on the system is the fuel pressure regulator, and the mustang 19LB injectors run at 37PSI, the fuel pressure regulator will be set at 37 PSI. When designing an FI system, always remember to put the fuel pressure regulator after all the injectors, in the return line, as this way, you will get the correct pressure before it. The way you get pressure in a hydraulic system is through blockage, and that is what a FPR does... It blocks the flow of gasoline UP to the pressure you set it. You really do not care about the pressure after the FPR, and putting multiple FPR's is just a recipe for a very hard to tune car as you have built up the pressure before the injectors. Some racing applications, and nitrous might use 2 or even 3 pressure regulators depending on the different needs, but that is way past what I intend to do with this car... I just want a nice car for a pleasant sunday drive, and if I get passed by a vespa, so be it.

Fuel rails, and old Air Slide Valve cover

When I took my intake manifold apart, one of the things that needed to be replaced, and that prompted me to go the megasquirt route was the air slide valve. If you can get one they are about 200 dollars, not too bad, but you have absolutely no control or coordination with the rest of the injection system. Unfortunately the air slide valve has a prong that extends into the intake manifold, at the coolant passage, and this needed to be dealt with. I could have just left the old air slide there, but it would not look good, and it would be in the way of the new air hoses, and the fuel hose joining the 2 fuel rails, so....
I bought a piece of 6060 aluminum stock, approx 1/2" thick, 3" long, and 1.5" wide, and proceeded to cut it to shape. I could have just left the square piece, but wanted it to resemble something that was not just drilled, so out comes the hacksaw.... If you have ever worked with 6060, this was a long tedious process. It is hard for aluminum, and after about 2 hours, I had a rough diamond shape piece.
I then proceeded to round up the edges, drill the proper holes, and recess them a bit, and now it should make an adequate cover for the hole. For the next car, I will do the same, and use this piece to put in the CLT, as no other mods need to be made on the Intake manifold (I previously had a 3/8NPT thread tapped out in the old thermo time switch position).
I also began the cutting of the aluminum stock for the fuel rails. By this time I was rather tired, so I have just cut one side. I plan on tapping the end of them for 3/8NPT, and using adaptors to AN6 all over.
Will post pictures once I am done.

Weekend Work.

Over the weekend in what little time I had, I managed to put the intake into the car. If the removal was not altogether that difficult, the removal, was pretty much the same. In general terms you want to put in the intake with the front radiator hose first. I replaced the hose, and the hose clamps while I was in there, as I do not want to touch this intake in a long time. The intake gaskets are also fairly straight forward, and are keyed so that they stay in place.

After the intake was in, I put in all the throttle linkage, the transmission vacuum, and the transmission linkage, and sealed the ports that used to be used for the two vacuum switches at the front passenger side of the intake manifold. I still have the port for the mechanical Air injection system to plug, but I am going to use a 1/2" think piece of aluminum there. It should be thick enough to hold the refrigerant pressure.

I took this picture from the driver's side of the car. You can see the repainted throttle linkage parts, the new bolts, and the "reconditioned" CIS housing. I chose to keep the housing, as I want to keep the gigantic air cleaner that goes on top of it. You can also see the hole that the secondary air injection valve used, and how it heats up. Mine was so stuck, that it wouldn't budege, even after repeated soaking in liquid wrench, followed by a freezing/boiling routine.

This picture shows the Air temp sensor on the CIS housing, as well, as the coolant level temperature sensor on the fron right of the intake manifold. The 2 bolts that seal what used to be the vacuum switches at the front left of the intake manifold are m10-1.0 metric bolts. I have a nice piece of aluminum stock that I will shape to fit in the hole left by the air valve at the front of the intake. I also chose to keep the air distributor, and will be using some hoses to connect them to the new Air valve that you can see in the bracket that used to hold the warm up governor. I still have some more work to do in the car after all is said and done, specially with the hydraulic pump, and the brake booster. Those will also be taken out, cleaned, and painted.

This picture is taken from the passenger's side. Here you can see the IAC on the side of the housing, how it does not interfere with the throttle linkage, and yet it will fit under the air cleaner housing. I will take out the now superfluos vacuum switches in the firewall to make room for the fuel pressure regulator. Notice the old safety cutoff cable that used to go to the top of the CIS housing. I am going to take that out, and clean up the cabling a bit. I never liked the solution to the cutoff, as if the car flipped, the linkage would stay open, and the cutoff never kicked in.

Heating Hoses

When I took the intake manifold off of the car, I found that the return hose for the heating system was routed underneath the intake manifold, and as the hoses looked rather ratty, I decided to replace the rubber hoses, and refinish the metal pipe that joins them, and runs the length of the passenger cilinder bank.
The hose against the firewall was routed inside the firewall itself. After taking off the little access cover to the vent system, inside the engine, I found that it was not going to be that easy... It ends up being that I had to remove the vent cover on the passenger side, and what is more, I had to drill out the fastener holding the hose in place, as it was rather rusted. I was going to replace them anyway with new hardware, but it took a bit of time.
After replacing the back hose, I moved over to the front hose. This was fairly easy, as it is only a 4" hose, with two clamps.
In preparation for the intake manifold installation tomorrow, I also cleaned the mating surfaces, and cleaned out the bolt holes. Now all that is left is to assemble the intake tomorrow, with all of its ancillary components.
This would be the first step towards the ultimate goal of replacing the CIS system. The following step is the fabrication of the fuel rails, and all the connections. I have already bought all the parts from Jegs and will start with that part of the project next week. I will post more pics of the Intake Manifold in the car, and all the linkages connected.

Pictures

I have taken some pictures of the work so far. I will do some work today before the fireworks, and have it posted Monday.

This is the engine block, after 2 days of cleaning, scraping, taking out a small nest, and finally finishing with heat resistant paint. Only thing is that it needs about 7 days to fully cure. I also covered the intake mating surfaces on the heads to prevent paint from getting into the valves, as that would generally be a bad thing.

This is the finished CIS housing. I have taken off all moving parts, drilled a hole on the side for the IAT, and made sure that I would be able to put the air cleaner housing on with the connectors. I also stripped it , and painted it with a coat of Eastwood detail gray. I replaced the bolts with yellow zinc plated bolts that I got from Wurth USA. They do look very good.

This is another view of the CIS housing showing the blocked off fuel distributor hole, and all innards removed. You can also see the IAT on the right side of the housing. I drilled and tapped it there after considering other alternate sections, but here I will be able to run the cables in an easy fashion, as I can bundle them with the Idle control valve, and the passenger side injectors.









This is the finished intake manifold seen from the rear (firewall side) I spent about 20 hours cleaning the intake manifold, only to find that the underlying aluminium cast was all spotted and looked terrible. In comes Eastwood, it is a bit brighter than cast aluminum, but it does look good. I also took the accelerator linkage and took it all apart, cleaned, sanded the 2 rods that make it all work, oiled, and reassembled it. It now looks much better, and is nice and smooth. Before it took quite a bit of strength to move it. I also cleaned the lower intake manifold, although I did not paint it.




This is a better look of the linkage. I reused all the parts that came with it, and it is a credit to MB engineering that after 30 years of use, and abuse, it only needed a quick shot of Eastwood black paint, and some minor sanding. The parts still looked almost like new, and the only change is the color, as the original was the MB golden cad, that is very difficult, and expensive to replicate today.... Anyway the black is easy to refinish, or even to strip. Notice also the intake manifold color. This section was the worst, as it was heavily stained, and no matter what I tried, I could not get the stains out... Even tried a mild acid.





This is a Idle control Housing that DIY Autotune sells. I also bought a 1992 Idle control valve for a Jeep 4.0 liter engine. I reused the bracket where the Warm Up Governor. As this is part of the CIS system, it will no longer be needed. The bolts on the left side of the housing were drilled and taped to M6 specs, as there is enough metal there not to interfere, or puncture the rest of the housing. Originally it comes with holes in the back of the housing, but due to the location, it would have been inconvenient. Now what I need to do is to find the right combination of hoses in between the CIS housing and the Idle control housing, and from the Idle control housing to the Air distributor (that I am going to keep, and just block off the port for the cold start injector).



In this pic, you can see the new lower intake manifold gaskets, as well as the cleaned ports for the secondary air injection, and the vacuum that is used by the transmission to shift. These were all blocked off by a layer of caked black goo, coming from the EGR that was stuck in open. Most of the time spent was cleaning the intake ports as they had about 3/4" of caked on soot... Making them much smaller, and blocking off all possible vacuum ports. Also when working with different kinds of metal, remember to put anti-seize on your bolts if you ever want to take them out without major problems.

Mercedes Benz C107 Megasquirt conversion

Hello All.
I am currently in the process of installing a megasquirt conversion on my 1976 SLC. I have been reading Oughtsix’s conversion, and I have decided to follow his advice almost to the t, except for building my own MS computer. I do not feel confident that I will be able to do a good job welding, as I have tried it in the past, and it has never quite worked for me.
So far this is what I have done:
Removed Intake manifold. I had a severe issue with vacuum loss (traced to a nice hole in the pipe coming from the exhaust for the EGR, and the fact that the Air control valve was stuck in open), and needed to isolate the problem, so I decided to remove the intake to replace those pesky rubber spacers in between the upper and lower manifold. This also helped me to clean, and seal the intake in a much better fashion. I also used Eastwood’s Co. Alumablast to refinish the top of the intake, and it looks so much better.
Had the thermo-time switch rebored for the 3/8NPT pipe thread needed for the CLT. I also took off any of the CIS components (Warm Up Regulator, Idle Control Valve, and the Air Distributor).
Purchased 8 19 LB mustang injectors. Tested the injectors and they do not need to be machined down, and the fit is nice and tight.
I took the old CIS Air intake, and sealed the CIS portions, and took out any moving parts… Including the Fuel Distributor…. Painted it with Eastwood Detail Gray, and drilled and tapped out a nice hole for the IAT... Figured that it would look really nice on the outside of that monster.
Removed all the accelerator linkages, stripped them, cleaned them, painted them with Eastwood black, and reassembled them. Now they have nice and smooth movements, and are not binding.
Bought the idle control box, and a 1992 Jeep IAC valve and tapped out two m6 bolts on the side, and I am using the bracket that used to belong to the WUG for it. Now need to get the right combination of hoses to connect it to the air distributor, and the (now inert) CIS intake. This should work as I am taking nice clean filtered air from the CIS, and through the air regulator am going to the intake manifold after the throttle body. BTW, the reason that I kept the original huge CIS intake was to keep the even bigger Air cleaner on top of it. I will eventually add a cold air intake, but more like the 560’s version that still has the large air cleaner… The reason for this is to have a large filter that allows more air in and gets dirtier less. (And still keep some semblance of originality).
Bought new bolts. As I had cap head hex bolts, I chose to replace them, as they tend to stretch and lose some of their strength after repeated torqueing.
Bought the Relay panel, the CLT, and the IAT from DIY autotune.
Cleaned the V of the engine block, and painted with temp. resistant black.
The idea is that anything that gets touched/removed is cleaned, and if needed stripped, painted, and reconditioned if possible, or replaced.
The plan as of today is to get some parts in (replacing the heater hoses that run UNDERNEATH the intake manifold) before dropping in the reconditioned manifold.
After the intake manifold is in, the injectors with new seals will be put in the car, and the electrical will start. I have decided to use the negative post of the coil for tach input, and wire the fuel pump from the relay board for safety reasons (the 76 had the safety switch on top of the CIS housing, and that got deleted as it would not be used, or useful.).
I will post some pictures of the work so far, and would appreciate any comments, and recommendations. I have found oughtsix’s site extremely helpful, but any other ideas would be greatly appreciated…. And no, there is not talking to me about keeping the CIS, as these systems are not well supported, or understood… They might have been state of the art in 1976, but…. Now, they are just a pain.
I do have a couple of questions though. I still need to find a nice power lead that is on both at run and at crank. I was thinking of using the lead coming from the old fuel pump relay, but are there any other ones closer to the engine compartment? If not, it is not a huge issue, as I need to run cables to the engine anyway.