1994 Mazda Miata Beater

Just a suggestion for future knowledge, you can actually swap to a Mazdda Millenia oil filter on these (Or at least on the 1.6L cars, I know) to get a little bit more oil and filtration capacity.

In reply to NickD:

That's good to know. I'll look into whether or not that is true for the 1.8 as well when I do the second oil change.

That 1"-3" of snow we were supposed to get ended up being up to 15" on my Saturday evening drive from Flint to Detroit. Luckily, I picked up a hardtop just 2 days before the snow. The snow tires on the Miata were excellent. I counted 19 cars off the road & the Miata just plowed through snow deeper than the body.

The power steering belt did start squealing this weekend though. It turns out that the adjuster bolt bent, which loosened the belt & allowed it to glaze up from slipping. I replaced both the power steering/AC belt & the alternator/water pump belt. I also changed the oil, oil filter, & air filter.

The upper ball joints are looking really bad. The boots are completely torn. I really need to get the press set up so I can swap those out.

Unfortunately, my DD is nonoperational at the moment because it started pissing fuel out onto the hot engine after my commute to work yesterday. Luckily I caught it before it had a chance to light up. I think it is leaking from the fitting between the high pressure fuel line & the high pressure fuel pump.

Well, your frame rails make me feel better about my frame rails, which only have one small section of rust perforation at the overlap joint. Wow.

Glad to see it getting saved though!

RedGT wrote: Well, your frame rails make me feel better about my frame rails, which only have one small section of rust perforation at the overlap joint. Wow. Glad to see it getting saved though!

The ridiculousness of this rust makes me wonder what I got myself into sometimes. Then I drive it & realize it is still fun. This loop of thoughts repeats ad nauseam.

frecks wrote: That 1"-3" of snow we were supposed to get ended up being up to 15" on my Saturday evening drive from Flint to Detroit. Luckily, I picked up a hardtop just 2 days before the snow. The snow tires on the Miata were excellent. I counted 19 cars off the road & the Miata just plowed through snow deeper than the body.

I always wondered how these cars were in the snow. I know the champion of the Adirondack Motor Enthusiasts Club ice-racing season for a few years was a Miata on Hakkapalitas

I'm going to need to order metal soon to begin my rust repair adventures. From reading on this & other forums, it seems like the bodywork on the Miata is around 20 gauge. Does that sound accurate?

NickD wrote: I always wondered how these cars were in the snow. I know the champion of the Adirondack Motor Enthusiasts Club ice-racing season for a few years was a Miata on Hakkapalitas

They're decent. Well balanced, low polar moment of inertia so they do what you ask. Obviously RWD and low ground clearance can limit you a bit. I drove them through 4 winters and liked it enough to get bored of my subaru and buy another Miata for this season.

Please post the sheet metal info when you figure it out, I'll need to do some too.

RedGT wrote: Please post the sheet metal info when you figure it out, I'll need to do some too.

Due to not owning a micrometer, my current plan of attack is to purchase some 20 gauge sheet steel & eyeball it to see if it looks the same. I'll let you know what I see once I get some.

In reply to frecks:

There is a tool for that.

Or a HF digital caliper, those are decent.

frecks wrote:

Good info here, I just went to the Forsch website. Very cool stuff.

My 2cents on metal- thicker may well be easier to weld. 20 ga everywhere on the chassis should be fine.You have a challenge ahead welding overhead on rusty metal. I look forward to progress reports. Get some TALL jackstands, and don't skimp on metal prep. Do you have a welder yet?

It's been a busy couple weeks with family stuff & working on the cars. I'm making progress though, slowly but surely.

I spent a few nights just practicing welding. Used up a 2 pound spool of welding wire, just sticking scrap metal together & filling it with beads. I'm just trying to see get used to how changing things (wire feed speed, voltage, push vs pull, stickout, movement speed, etc...) affects the output of the weld. It's a lot of fun being able to stick metal together.

I picked a turbo from a local junkyard for like $50 with their 25% off sale over thanksgiving weekend. It is a Garrett GT17 from a 2003 Saab 9-5 with the 2.3 liter engine. I couldn't find the official compressor map for it, but I found some estimated compressor maps. The turbo is super tiny, but it looks like I should be able to stay left of the choke line as long as I stay under 10psi of boost. I don't plan to push it that high though. I'll probably stay much lower to keep costs down & avoid blowing (as much) E36 M3 up. This turbo thing will probably be a long process as I'll have to do lots of research & there will be much trial & error.

I need to figure out how I'm going to handle fuel & ignition with the turbo. Ideally, I would just use a MegaSquirt, but that would probably blow my chances of selling stuff to get down under the 24 hours of lemons budget unless I find one for an absolute steal. More realistically, I'm hoping that I can find a dirt cheap rising rate fuel pressure regulator if I'm patient enough & I might just have to deal with retarding my static timing if I can't find a cheap enough solution for that.

I've also realized that I'm going to need a way to check my AFR to make sure I don't mess things up too badly. I would also like a way to make sure that I have the jetting right on my Suzuki DR650. I'm thinking it's probably time to invest in a wideband o2 sensor. It looks like I should probably go with the Bosch 17025 LSU 4.9 for the actual sensor. Then I need to figure out what to do for a o2 sensor controller. I want a portable solution that I can use with the Miata, the motorcycles, or any future projects. I think that would fit my needs better than a permanent install in the Miata. I would like to keep it cheaper, but I also don't have a problem with paying a reasonable price for a tool that would last a long time & be useful over many years.

On Saturday, I adjusted the window stops so they line up better with the hardtop. I cleaned & re-greased the window track on the driver's side with the hope that the power windows would work a little better. It definitely helped, but I still question how long it will last. Time will tell. I also picked up some foam insulating rope that I'm going to try to stuff in the weatherstripping on the hardtop to make it seal up a little better.

The Miata got her first wash in what seems like a decade last night. I tried to clean out the engine bay since a clean engine makes diagnosing leaks & wrenching in general way easier. It was a bit of a pain, but came out way better than expected. I filled the gallon sprayer about 1/4 full with a 75:25 mix of citrus floor degreaser & water. I probably should have filled it a little higher, but this worked. Sprayed the engine bay down with degreaser, washed the rest of the car, then came back to the engine bay with the power washer. Sprayed the engine bay a second time, let sit for a few minutes, then power washed again. I was a little overzealous with the powerwasher, as the car felt like it was only running on 3 cylinders as I pulled out of the car wash. I must have gotten something wet that shouldn't be wet. Luckily that cleared up after about a mile & things were normal on my commute to work this morning as well.

My attempts at adjusting the windows & stuffing foam in the hardtop seals helped, but not enough. It drastically reduced how many rattling sounds there are in the cabin when driving over rough roads. It did not prevent the water from getting in between the window & the seal. I'm going to try using some of that Shin-Etsu Grease that Miata owners seem to rave about. Hopefully that plumps up the seals some. If that doesn't work, I'll have to remove the seals from the hardtop & silicone them down in the proper positions. I really don't want to do that.

Engine bay before cleaning:

Engine bay after cleaning:

I'm going to check the spark plugs out tonight if time permits. I assume they're way past due for replacement. The exhaust smell has been a bit stronger than I think it should be since I got the car. It isn't very bad, but I'm thinking it might be incomplete combustion due to very old spark plugs.

I also greased all the linkages at the clutch pedal this past weekend, which successfully eliminated the squeaking sound that happened every time I pressed the clutch in. It's amazing how much of an effect eliminating little sounds and annoyances like this have on overall feelings about driving the car.

The plug tips were a bit on the light side, but were in overall better shape than I expected. They were Autolite plugs with a heat range of 5. I ended up putting in NGK BKR7E plugs. It seems like that is what recommended on the miataturbo forums & I eventually plan on having forced induction.

I also decided to compare my spark plug gap tool to my set of feeler gauges & discovered that my spark plug gap tool reads .012" different than the feeler gauges. The NGK BKR7E plugs should come already gapped to .035". The largest feeler gauge I could fit in the gap was .035". The spark plug gap tool read .023" for the same plug.

Got the steel for repairing my "frame rails". I'm pretty sure the girlfriend got me some welding supplies (wire, tips) for Christmas, so I'm hoping to get started on this shortly after!

Just showed up to work. Pulled up at the stop light in front of the office after an 18 mile freeway drive and ... no brakes. Thank god for manual transmissions & no traffic at midnight. I was able to safely get it to stop & limped it into the parking lot.

I can push the pedal pretty much all the way to the floor with my pinky.

The brake fluid is MIA.

I wonder which line I blew. If my understanding is correct, the Miata has a dual circuit system with an individual circuit for each axle. That would explain why I still get a small amount of stopping power once the pedal basically reaches the floor. I guess there's a possibility that I blew out a seal on a caliper, but I figure a brake line probably rusted through.

That Millenia fliter does fit the 1.8, I use it on my '94 with a '99 engine. And if a bigger filter isn't enough to sell you on it, at Autozone, the Pure One version is a dollar cheaper than the smaller Miata spec unit! Go figure!

Looks like it's already had some line work, unless Mazda used polyarmor line at the factory. Rust on the booster under the MC indicated it has or at some point had a bad MC, remove the two nuts, pull it forward a inch or so (lines won't mind bending a little), and check for fluid there. You probably have a blown line, but a leaking MC is a hazard.

In reply to Kenny_McCormic:

The previous owner said that he had replaced the master cylinder, so your analysis was correct. It appears that he also replaced the front brake lines in the process. I couldn't see much when this happened because I had to work midnight to 8am. When the sun came up, I was able to go see that it blew out the rusty rear line right before the tee off to each side. The VP of my department brought me in a metric wrench set & let me borrow his truck to drive to O'Reilly in the morning. I disconnected the rear brake line & capped it off at the ABS distribution block. Refilled the fluid & got some of the air out of the lines. That restored functionality of the front brakes & was good enough to get me home. Picture of the parking lot "fix" coming soon.

I've got some brake line work to do on my parent's Yukon as well, so I'm probably going to buy a nice brake line flaring tool & fix both cars.

I don't think I would use the NGK BKR7E with a non-turbo car. It's just not the heat range for an NA car. I'd save those for if you actually go to a turbo car.

Yeah, I find you generally get best performance from a stock car with the exact plug listed on the hood sticker or in the owner's manual.

Luckily, plugs for the Miata seem to be dirt cheap so I'll just get some 1 level hotter & save these for when I figure out the turbo.

Parking lot fix: Blocked off rear brake line from the ABS distribution block so I could get home.

Best flaring tool for the $$, imho, is the ridgid kit. It is about $100-$150 and works awesome. I even preferred it to the hydraulic kit a friend was using.