Tuesday, April 14, 2009

A little bit there...

More dismantling tonight. I didn't get dirty, though, because I didn't go under the car at all! I think that's a first. Instead, I started ripping out the interior. First to go were the front seats. Surprisingly (to me) the front seats are only held in by 4 little bolts. The bolts were unlike anything I had seen before, kind of like an inverted torx design, but an 8mm socket fit over it well enough to get them out. They were a bit stiff because they're coated with Loctite during installation (I will need to put more on when I put the seats back in) but they came out without too much strain. So did the seats.

Next I tackled the back seat. It was even easier to get those out - no bolts at all - just a couple of push-fittings and then a bit of manipulation. Good thing I have the official manual for this car, as it wasn't obvious at all what to do just by looking at the seat. The rear seat belt attachments were a little trickier, but they were no match for the 600 ftlb air wrench followed by a 2 ft breaker bar! A little bit of sweat and, voila, no seats!

It was too late to take any measurements for the battery box, though. And I'll be traveling for a few days so I won't be able to get back out to the car until next week.

A little bit here...

Spent a little more time on the car last night. Boy, am I ever slow with this stuff. Took me almost 2 hours just to get the gas tank straps, muffler hanger, and exhaust heat shields off the car! Well, ok, before I got down to it I decided to raise the car up higher on the jackstands to give me more room to play, and rearranged some of the parts I've taken off so I don't lose anything. But still... I'd better get it in gear if I want to have this car on the road before next school year!

Last night I also took some measurements to start designing the motor adapter. My friend convinced me that we can build one ourselves so that I can save the $800 or so that the component suppliers charge to make one.

Today I think I'll make some calls to ElectroAuto (and maybe CanEV) and see about placing the big order. If it is true that it'll take up to 8 weeks to deliver, I need to get moving.

I'm waffling a bit on the PCM issue. The more I dig into it (from other EV conversion blogs, emailing other EVers, and reading shop manuals) the more I think it would just be better to leave it in and "hide" any lights that I want to ignore. I can always upgrade later, right?

Tonight I start to tackle the back seat. Gotta gut the interior so I can make the final measurements for the battery box designs. Then there are plenty of other tasks to complete while I'm waiting for the kit components. More later....

Friday, April 10, 2009

What to do with the PCM?

Things are still moving slowly with my conversion. Gas tank and gas lines have been removed, but not much progress beyond that. I've been very busy with other commitments lately - I'm hoping things will calm down after next week.

No huge surprises in removing the gas tank, except that the air wrench (600 ftlbs of torque!) was not able to break the bolts holding the gas tank straps. They didn't look that bad, not too rusty, but the wrench wouldn't touch them. So I ended up prying the strap hinges out of the frame instead.

While under the back of the car, I did notice that one of the suspension components (stabilizer link for the sway bar) on the driver's side had snapped. Shouldn't be difficult to replace, but I'm wondering about the added stress of 800 lbs extra weight back there. May have to do some engineering calculations and see if a beefier component is warranted.

At some point I know I'm going to be bringing the engine and exhaust pieces somewhere for recycling (scrap metal yard?) but I don't know what to do with the gas tank. I've heard rumors that it is a very difficult thing to get rid of. May be worth an EVDL (Electric Vehicle Discussion Group) search on the topic.

Another aspect of the conversion weighing on my mind is what to do with the PCM. In my mind, there are 4 options with the PCM:

1. Leave it untouched. Simplest approach, but then I either have to look at the MIL all the time or cover it up. Question: Will the PCM work at all without receiving signals from a non-existent engine (for instance, vacuum sensors, temperature sensors, crankshaft sensors), or will it assume that the engine is off all the time?
2. Leave the PCM but create a magic box which will fool it to believe that the engine is running, and running properly. The magic box will no doubt be very complicated, especially if more than a couple of signals will be required to keep the PCM happy.
3. Reprogram the PCM so it ignores inputs which are no longer pertinent. Complicated, and I believe will require a special interface and software.
4. Remove the PCM. My preference, since it is the most elegant (remember, I'm really out to save the world by getting everyone to convert!). Questions: What other systems rely on outputs from the PCM (ABS, SRS, instrument panel, etc.)? Will the car pass annual inspections without a PCM? (According to the Mass RMV website, the OBDII check is done only for emissions purposes and thus would not apply to an electric vehicle. But how do I confirm that?)

I've started to ask other EVers (and done an EVDL search) on the PCM topic, but thus far I haven't gotten a consensus. Some go with Option 1 without any obvious issue, but I wonder if it is car-dependent. Some decide not to convert anything with an OBDII connector to avoid the problem.

In the meantime, I'm hoping to get some time Sunday to get rid of the last straps for the exhaust and gas tank, start gutting the interior, and take a few measurements for the motor adapter. Until then...

Saturday, April 4, 2009

Dismantling the car

Full disclosure time. The previous two posts were "catch-up" entries. I hadn't really thought about setting up a blog to record my progress until a fellow EVer I was corresponding with suggested it (thanks, David). So I decided to put some background info in the blog before moving forward.

In late February a '98 Saturn SC2 showed up on Craig's List with a blown engine. I went to see it, saw that the body and interior were in pretty good condition, and made an offer. I ended up getting it for $500. Not bad. Unfortunately, the car was sitting in a driveway (not drivable, obviously) 90 miles away from where it needed to be. So, ouch, the tow was more than I want to think about, but I still was under my target of $1,000 for the donor.

I have a garage at my house, but it's a tiny 1-car with a very low ceiling. Not conducive to massive auto transformations. Lucky for me a good friend of mine has a large detached garage that is relatively unused. Even luckier is that she has a large, rolling toolbox full of goodies (she's done a considerable bit of car work herself), including an engine hoist and air tools. And, luckiest, I have another good friend who has lots of experience with this kind of work, and willing to help me out.

Cold weather and my busy schedule has limited my progress with getting the combustion components out, but I've been making steady progress.

Here's the car just after being pushed into the garage. The garage looked big before the car went in, but there's not much space left now! Better re-arrange things in there before going too far.

The paint looks pretty good, though I'm not big on the color. A visit to Maaco may be in this car's future.

The interior is in pretty good shape. Bit of wear on the clutch pedal, though. We'll have to see about the condition of the clutch.

Looks like the engine has had its share of problems in the past. Valve cover gasket has been replaced (new blue gasket) and oil has been slung all over the pulley end of the engine compartment. These pictures don't do the mess justice. I wish the car ran well enough to get it to a carwash so I could steam clean the oil off before starting the disassembly.

Once I lifted the car and started peeking around underneath I realized that the oil mess wasn't confined to the pulley end. Bell housing and tranny are also drenched in oil. What a mess!

Now the fun begins! It's amazing to me how much stuff automakers cram into the front end of their cars, and how much stuff is needed to make a combustion engine work. Every time I pull something out, it reveals 3 more things to disconnect. I'm trying to label things as they come out - since this is my first attempt, I'm not 100% sure what I will or won't need once I start installing electric components. But after many hours of preparation work, the day finally came....

Finally, an empty engine compartment!

And a lonely pile of metal and oil.

Good news, though. Looks like the clutch has been replaced recently, so I won't have to pony up for new parts there. I do have my work cut out for me, though, in cleaning up the tranny before reinstalling.

It's starting to feel real now.