| THE MG |
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 | |  | September 3, 2010 - The ugly truth.
There's a spot in the engine bay above the passenger's feet where one of the main MG harnesses erupts from the fender. Just below that, I've mounted the GM computer and rerouted the other main MG harness through the cockpit to arrive at this same location. It's quite a traffic jam.
I'm tracing through the MG harness to pull out unused wires and to figure out how some of it works. I'm doing a lot of electrical forensic work as I try to identify a number of the connections. I know there's a hookup for the reverse lights in there somewhere...
The first splice between the GM and MG harnesses was made yesterday - the alternator light. The ignition switch is also wired in, so I can check that the appropriate circuits will be energized when the battery is installed. Since the MG harness has a few unknowns for me, I'm being particularly careful to avoid stray electrons.
entry 387 - tags: wiring | | |  | September 3, 2010 - I do love my bead blaster.
This is a relay for the starter solenoid - probably added to the MG over the course of production to protect the poor ignition switch from the power needed to trigger the solenoid. The Miata switch is robust enough to handle it, but the wiring in the MG harness is a little smaller than I'd prefer. So I'll keep my relay to trigger my solenoid to trigger my starter. At least, that's how I'm thinking now.
Just look at what 20 seconds in the bead blasting cabinet did to this (probably) 38-year-old component. There's no corrosion on those contacts!
entry 388 - tags: wiring, bead blaster | | |  | September 3, 2010 - The pedals have been dropped into place.
I figured the pedal box installation would be easy - I've been told the power brake components simply bolted into place of the old pedal box. Umm, no. A number of the holes didn't line up and I had to cut an extra slot in the firewall for the brake pedal. Then I discovered that it has to be partially assembled on the car. Lots of fun!
But it's in.
entry 389 - tags: pedal box | | |  | September 7, 2010 - I was hoping to get a lot of work done on the car over the long weekend, but life got in the way.
Lots of other jobs to do. But I did sneak down to the garage and solve one major problem.
As part of cleaning up the garage - I had to pull the Seven out of the trailer in preparation for a track day, and this meant I needed an extra parking space - I dropped the MG hood on to the car. This reminded me that I needed to do something about the oil filler neck interfering with one of the ribs on the bottom of the hood. Without much time to spend in the garage working on it, I turned to Google. That's where I discovered that the neck is simply clipped in to the valve cover. When removed, the stock filler cap will screw right into its place. Perfect!
It's possible to force this part off, but you'd break a locking tab that keeps it in place. The clever way is to remove the valve cover and pull back this little tab (visible in the picture) so the neck can be removed. That took all of five minutes. And voila, problem solved! The hood now clears every part of the engine.
If only all my problems were that easy to fix.
entry 390 - tags: clearance, oil filler | | |  | September 7, 2010 - Janel and I have realized that the interior of the car is going to need some attention.
We bought this particular car because it was black with a tan interior, and it looked great. Of course, then it turned out to have a bad paint job and the interior was just spray painted. But we still got a good rust-free chassis!
Of course, if we're going to refresh the interior we have to deal with matching the paint or replace it all. The latter is tempting but we have the problem of the headliner. I do not want to replace it - and it actually looks pretty good.
Looking at various color samples online, it appears the (unpainted) seats are "biscuit" and they do match the rest of the interior. Unfortunately, Moss Motors doesn't sell this color for the GT, only the convertible. I found a shop in the UK that offers a full biscuit interior for the GT but I wanted a color sample to be sure. And here's what showed up in the mail today!
The good news is that I was right. The seats are biscuit and match the sample perfectly. The complete interior does include new seat coverings, but this way we know everything will match. Yay! A big thumbs up for Chase MG. I'll put in an order for the parts soon. It actually quite affordable, a full interior for less than the price of two seats from Moss.
entry 391 - tags: interior | | |  | September 7, 2010 - The new brake master cylinder is here.
I did some calculations a while back on brake master sizes, and the ideal (to match the Miata) ended up being 15/16". My plan to use the Miata booster fell through due to a critical lack of space. Well, I have the choice of the old 7/8" setup from the MG or a 1" Wilwood caliper. Since almost everyone prefers a hard pedal with a bit more effort to a softer one, I've decided to go with the Wilwood setup. This also means I don't have to mess around with British flares! I'm not going to bother with the brake plumbing yet, but since the master arrived I just had to bolt it in.
I also bled the clutch hydraulics, so I should theoretically have a functioning clutch. I don't have any way to tell for sure yet - I'll wait until Janel is around, then see if I can spin the driveshaft by hand when the clutch is depressed. Oh boy, I sure hope so. It feels good anyhow.
The power steering lines are also fully hooked up now. By this point, all the fluids in the car (other than the brakes) should be contained. So it's back to wiring...
entry 392 - tags: clutch, brakes, steering | | | September 9, 2010 - Power!
With a few spare minutes in the garage and a freshly connected main relay, I hooked up the battery to the car for the first time. First, of course, I had to come up with a good grounding point. Hopefully I did.
When I connected the battery, nothing happened. That's good.
Then I flipped on the main circuit breaker. Nothing happened. That's good.
Then I turned on the ignition and saw a light come on inside the dash. Must be the alternator light. I also heard the main relay click over and the fuse panel for switched power came alive. That's good!
No sparks, no shorts, no nasty smells. All the smoke stayed inside the wires. This may not seem like a big step, but now that I know I have a smoke-tight electrical system it'll be a lot easier to trace wires and determine that everything is hooked up correctly.
Woohoo!
entry 393 - tags: wiring, smoke, electrical | | | September 13, 2010 - I was at a track day this past weekend, exercising the Targa Miata.
So no work done on the MG. And I'm going to Oklahoma for a track day this upcoming weekend, so no work will be done this week either. But I did take 5 minutes to do a quick check of the MG's clutch. Janel was involved in the driver's seat while I crawled under the car to slide the driveshaft into the end of the transmission. Then I crawled back out, jacked up the rear axle a bit for more clearance, and crawled back under to slide the driveshaft in place.
Poor Janel had to follow instructions like "put it in gear. Okay, now put it in neutral. Now put it in gear and press the clutch down". Meanwhile, I was trying to turn the driveshaft. Good news - with the car in gear and the clutch engaged, I could not spin the shaft. But with the clutch pedal down, it would spin freely. This means the clutch is disengaging fully. Janel did not seem as excited as I was.
entry 394 - tags: clutch | | | September 30, 2010 - Wow, three consecutive weekends of track days followed by a weekend of off-roading in the Colorado mountains.
Followed by a few days of being seriously under the weather. Lots of fun with cars, but no time for the MG. I'll be back on it this weekend, though. Various bits and pieces required to piece the intake together have been trickling in. It's going to be tight. Of course.
entry 395 - tags: intake | | | October 5, 2010 - Trying to pick up from where I'd been, a month later, is a challenge.
Especially with wiring. But I've sorted out what I was doing and I'm starting to make forward progress again. Nothing big or exciting, just careful connection and testing of one circuit at a time.
entry 396 - tags: wiring | | |  | October 6, 2010 - Woohoo!
This might not look like a whole lot, but it means the electrical system is live and I can talk to the engine computer. All the sensors that could be expected to have readings with the engine off have readings, and they're all accurate. The throttle is wedged slightly open in case you're wondering about that 11.8% reading on the TPS.
Once again, no smoke was released. This is all going well.
entry 397 - tags: wiring | | |  | October 6, 2010 - Time for a good day of work.
I have a goal! First, I need to get the exhaust system assembled. I figured out good O2 sensor locations, drilled the pipes and welded in bungs for the two sensors. Easy enough. I also added a new hanger at the back on the right muffler to match one that was already in place on the left.
entry 398 - tags: exhaust | | |  | October 6, 2010 - All the parts have arrived for the intake system, but I'm still trying to decide exactly how to plumb it.
It's hard to get a 4" tube in between my engine and radiator! So, for the time being, I simply laid the filter on the fender for testing.
entry 399 - tags: intake | | |  | October 6, 2010 - My clever header design does cause problems with the spark plug wires.
So I dragged out a set of wires from the old Cadillac and pressed two of them into service. It's not pretty, but it'll do the job.
What job? I'm aiming for the first start on the car. It's close, really close. So most of the day was spent doing a lot of the little jobs that hadn't been done before.
entry 400 - tags: plug wires | | |  | October 6, 2010 - The last step before trying to start the car was to put some fuel in the tank and pressurize the system.
That didn't work! Well, it did, but not completely. The stock MG fuel system uses a couple of flared fittings that, typically for the British, are probably only found on Spitfires and MGs. One of them's on the fuel tank itself. So in order to plumb everything together, I retained one of the original fuel hoses in the return line. Bad idea. As soon as the system was up to pressure and excess fuel started to feed back to the tank, this thing started leaking like a garden hose. The inner rubber hose must be cracked in at least 10 places.
So I pulled the hose out and managed to piece together a replacement using one of the end fittings. After a bit of fiddling around, the fuel system was happy and full of pressure.
entry 401 - tags: fuel | | | October 6, 2010 - So?
Did it start? Well, no. It cranks happily and I did get it to cough really briefly, but overall it's just not exciting. Here's where the OBD-II scanner comes in handy. I can see that all the various sensors are reading properly - there's even measured airflow going through the intake on cranking - but the engine RPM is stuck at 0. If the computer doesn't think the engine is spinning, it's not going to try to fire the injectors or spark the plugs.
I checked the wiring for the cam angle sensor and the crank angle sensor. It's good in both cases. When Janel's home tomorrow, I'll check to make sure I'm getting spark. But that 0 RPM reading kinda tells me what I'm looking for first...
entry 402 - tags: start, wiring | | | October 6, 2010 - I posted a question about the no-start behavior of the MG on LS1tech.com, and got an answer almost immediately.
I need to disable the VATS system. That's an anti-theft setup that uses a resistor in the key. Since I'm not using the Camaro ignition switch or key, it needs to be bypassed or turned off.
A tuning program like HP Tuners can be used for the latter, and we have a copy at work. I also need to do a few other things such as turn off the EGR and the rear O2 sensors. HP Tuners is expensive - but luckily, Flyin' Miata has a copy. I'll have to pay to "mate" it with my computer, that that's fairly inexpensive relative to the cost of the program.
Will this fix it? Let's find out!
entry 403 - tags: start, VATS, HPtuner | | | October 7, 2010 - I borrowed a laptop with HPTuners software from work.
As soon as I got home, I hooked up the laptop, fired up the HPTuners software and used it to turn off a number of vestigial appendages in the car's computer. VATS anti-theft: off. EGR: off. Air pump: off. Rear O2 sensors: off. Skip shift: off. A quick upload and voila. The car should be ready to start.
I should point out that this is pretty common software. Most shops that tune GM engines have a copy. I suspect my local machine shop would be able to do this for me. You can also send your engine computer off to have it done elsewhere - for example, Painless Wiring will reflash the computer with these sorts of changes for free if you buy one of their harnesses. The fact that I have access to the Flyin' Miata copy simply means it's more convenient for me than most people, that's all.
Another alternative would have been to build an inexpensive VATS bypass. The plans are pretty easily found online, or you can buy one pre-made. There are lots of ways to solve this problem. Since I also wanted to turn off a few other features, the reflash was the best option for me.
entry 404 - tags: HPTuners, PCM, ECU, VATS | | | October 7, 2010 - It's aliiiiiive!
After reprogramming the computer - which took about 5 minutes, using software I'd never seen before - I ran upstairs and told Janel I had a surprise for her. She didn't know how close the car was to starting. I jumped in the car and hit the key. It cranked for a few seconds, then a few seconds more. But it was trying. So I tried again and VAROOOOOOOOOM! Lots of noise, lots of revs, and a running engine.
I caught it all on video. It's a cinematic masterpiece, with expository dialogue, a build-up of tension and then a big climax followed by a happy denouement. In case you're wondering, I was talking to Janel who is standing at a safe distance behind the camera, taking refuge behind the Mini.
Watch it!
It wasn't completely successful. The first few times it didn't want to stay running more than a couple of seconds. It eventually settled down and kept running, but at a 2500 rpm idle. Since the main goal was to simply get it to work, I declared that enough. Even just a few seconds of running was enough to get the paint on the headers to bake in and release a nice cloud of smoke. I'll spend some more time cleaning up the wiring and hunting for vacuum leaks. Maybe this weekend I'll let it run for a bit longer to see if the engine speed will settle down as the computer re-learns this engine. The change in behavior from the first start to the fourth was notable.
First I need to blow the smoke out of the garage. Whew!
entry 405 - tags: first start, engine, video | | | October 12, 2010 - More progress.
A quick test with a smoke machine uncovered a vacuum port on the back of the intake manifold, underneath the MAP sensor. Almost impossible to see, and now capped. With that done, the idle quickly settled down under 1000 rpm and was continuing to improve when I shut things down. So it's looking as if the engine is a happy bunny.
I found an error in the wiring diagram I'm using. The engine computer is supposed to have a constant 12v feed to store all the various internal settings. According to the diagram, that feed was switched power so it only turned on with the key. Every time the computer loses power, it needs to relearn various settings such as the idle - so this would have been an annoying problem. Fixed now!
I'm working on related wiring now. The coolant gauge is hooked up, but the engine hasn't been hot enough to test it yet. I'm working on the tach now.
I also picked up all the pieces I need to complete the braking system. At least, I think I have all the pieces now. I'll start working on that soon, as it's the biggest step preventing me from actually driving the car. Ooooo!
entry 406 - tags: brakes, wiring, engine | | |
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