So up until 12 months ago, it was not using a drop of oil. Then it went to using a quart (0.95l) every 1000 miles (1609.3km), then every 900 miles, and so on, until we got to the point where I am adding oil every 600 miles. Needless to say, I don't like where this is going.
So I began looking at my options. There are a bunch, too:
- Get the existing engine rebuilt for performance, with overbore and the whole shebang. That would be in the $3-4000 range.
- Buy a new engine from Mazda Motorsports (their racing development arm) for about $2500. That comes without any warranty though.
- Buy a used low-mileage engine for $900-1300. They usually come with parts and labor warranties ranging from 3 to 36 months.
- Take a wild guess that it's the valve guide stem seals and have those replaced without pulling the engine head for about $500. If it's not the valve stem seals (could be oil control rings, or something else for all I know), that might not help much or at all, making it money thrown away.
- Do nothing, just add oil, until I run on oil and gas mixture, like a chainsaw.
- Sell the car.
Here's the entertaining part: I requested quotes for used engines from a number of junkyards, and a handful replied saying they had the engine I need. My follow-up question to all of them was the same: "What year is the donor Miata? Is the engine 1.8 or 2 liter? How many miles on it? Do you have leak-down test results and/or any other test results for this engine?"
Here's what some of the replies were:
Are peace of mind & better choices important to you?
Does accurate mileage & a valid warranty matter?
To proceed, what do you plan to spend for condition, mileage & warranty you can verify?
ASK YOURSELF: "Can I afford to do this over & over, if the part is wrong, or fails sooner than I expected?"
It is of course encouraging to see people comfortable with copy-and-paste functionality, however their use of it did not bring me any closer to knowing whether they had what I wanted.
And the quest continues.