cyl head removal and oil pan removal.

It is possible to remove the pan while the engine is in place. It is not easy to do so. The subframe holding the engine and suspension must be lowered and the engine supported by other means. Why are you considering a rebuild of the cylinder head?

The car involved smokes a puff of oil at startup. This is usually indicative of the valve seals failing, and if the mileage is high, it is also probable that some valve stem wear and valve guide wear has happened. Most >100,000 mile cylinder heads need some work. Most well built Japanese cars wear very little in the cylinder. The blocks usually do not show much wear. However the Miata has a relatively thin oil spreader ring and it often gets clogged up. If the oil pan is easily removed (sounds as if it is not) then I would recommend replacing the rings. If the oil pan is a PITA to re-re, then I would probably pass on the ring job.

Try replacing the PCV valve first. You might be pleasantly surprised.

Been there, Done that. In this case the puff is upon cold start, and quickly disspears in a few seconds. This indicates worn seals and probably worn valve stems/guides. I try and replace the guides with undersized guides and hone the stems to a smaller diameter. But in severe cases the valves will need replacing as well. If so I hone the inside guide diameter to match the valve stem size plus clearance.

Besides this is only the first of my miatas. I plan to purchase and refurbish many. I think it might be a good idea to rebuild all top ends. So as to give the new owner a "fresh start".

While I am here, Is the ransmission (Standard manual shift) hard to remove and replace? I also think a fresh clutch might be a good idea....

Mike..

If you're going to remove the gearbox and the head for work then it only a little more work to remove the engine and gearbox as a single unit - It can even be easier as the car doesn't have to be high enough to drop the gearbox. Then you can rebuild it with ease.

Martin (cogitating this very job when it warms up a bit).

I know... I thought of this just after i hit the "send" button.... Maybe i should just get really good at re-re the entire package, place it on a engine stand and hone the cyls, re-ring, and get the heads done. Refacing the flywheel adding a new pressure plate and a clutch... The real work here would be to get all the parts required at the best possible prices. Even a gasket kit for the miata is expensive. There must be wholesalers of this stuff so a person could buy at a much better price than i have seen on ebay.... Valves and guides and seals I can get from reasonable cheap sources, as well as rings and pistons. Gasket sets are a huge cost.... I doubt i will need to rebore much, and the camshafts are usually good enough to not need regrinding. The hyd lifters can be rebuilt with a simple cleaning, and oil pumps usually only need a cleaning. Bottom end and rod bearings are usually ok to reuse, but they are not expensive either. Obviously they would need replacing if the crankshaft needed regrinding.

And yes... I used to run/own a engine rebuilding shop in a previous lifetime.....

It's been my experience that Japanese engines have very long lived valve guides and valve stems. It's not difficult to change the stem seals with out removing the head. If you do remove the engine the clutch will be attached to it, so no need to remove the trans. The factory recommends removing the trans with the engine, but removing the engine only is much less work.

True. If that's all it does, you might want to fix it in...oh...say, another 30,000 miles, or maybe at the next timing belt job. My '85 Accord started doing that last year, and there's no way I'm rebuilding the head on a $500 car that otherwise runs fine.

If it's using enough oil to need a quart between changes, that's another story. Or if you simply enjoy engine work as a hobby, because you'll never get your money back out of unnecessary repairs.

What year Miata are you doing all this engine work on ?? Soon you will have enough money in it you will not be able to get your money back to just sell it! If you are going to keep the car for yourself, than it's not so bad, but an older Miata just will not be worth much to sell to someone else. I know of a '90 with newer paint, a '93 engine, a new top, KYB shocks (almost new) lowered springs and top of the line maintance on the rest od the car. $3,000.00. I don't know what you paid for the car you have, but I hope someone gave it to you. :-)

Bruce Bing '03 LS

Are you suggesting that this turbo 1990 model that is putting out white smoke might not get $8,000? ;-)

Hi Pat, If you take the turbo off, you might get $8,500 ! :-) Pulling the baby apart and spending $$$ kind'a makes it hard to get the $$ you spend fix'n it up. Kike I said, if it is for youe self to play with, then I know guys that pour big bucks into a car and never get that money back. With that, they are doing it for the FUN of driving car for themselves. :-) I know of a guy, Bruce, I think his name is, that put tons of money into a red '91 just for the FUN of driving it. :-)

Bruce Bing '03 LS (had a '91 red) :-)

What is funny is how much you can get back for aftermarket miata parts. I bought a used set of JR sways, re-used them for 5 years, and then sold them for a profit. My Hard Dog rollbar was around $250.00, they had free shipping and discounted me $50.00 for a scratch. I sold that one for $180.00 after using it for 5 years as well. It looks like I will get back about $1,000 less selling the parts than I would have if I had sold the car unwrecked, but it has been/will be a lot of labor.

I have no doubt that I could part my current car out for more than I could sell it for alone, but having just removed the dash, ABS computer, and a number of other parts from the dead '96M, taking miatas apart is becoming tiresome, and I still have a dead '91 Silverstone, (blown/warped head gasket, broken radiator, needs full timing belt service, maybe more), that would be a great car, but once it is fixed it will still be worth about $2500.00 max. If I take it apart that will be parting out miata #3, I don't think I want to do a number four.

Hmmmmm......

Pat

Pat, you are correct. Selling aftermarket equip., I think you can get the money back out as long as it is not damaged or a wear related item like a supercharger. The system works a lot like parting out an airplane, it is worth about four times as much apart than it is flying. :-) parting out a car is kind of like that and with the two, only if you don't count the cost of your labor. Like I said, if you are doing it for your self and going to keep the car, you can pour much more money into it and still feel good. :-)

Bruce Bing '03 LS

Pat, that Silverstone would have to be trashed (IMHO) to only be worth $2500! I've never seen one, in any condition, go for that little. What's the body / interior like? Maybe an engine swap is in order.

Chris

I still remember being much younger and getting frustrated at pouring money into a car. I told the mechanic something like, "I could buy a new car for not much more than the cost of replacing the parts". He then explained that no, I would need enough money to buy a number of the cars brand-new if I was going to buy all of the parts separately, and that didn't count labor. That is when I realized how it all worked with vehicles.

Hard to believe that was over 20 years ago, yikes!

Pat

It is a hard decision. The engine needs to be swapped or rebuilt, I happen to have a 1.8 liter engine with 75K miles and a perfectly functioning 5-speed attached. The car has been bumped just hard enough in the front to do a bit of damage to the hood and both headlight buckets, but again, I have all three of those parts ready to bolt on, though they would need to be re-painted. I even have a set of 15" OEM alloys for it from a 2001 miata.

The car has 120,000 miles. It has a near-perfect Robbins glass window top, the Skip Cannon rear brace, FM STB with hood prop, FM sways, Momo steering wheel, voodoo knob & handle, and probably a few other goodies. This was never my car to drive and I still need to look it over some more. The interior is in very good condition.

So I can either restore this car or sell both the parts that I would use to restore it and the ones that are on it now, including things like the trunk lid, power window motors, doors, seats etc.

It only makes sense for me to restore it if I am going to keep it, otherwise I will come out ahead financially by tearing it apart, as much as I hate to do that to a Silverstone with a straight body.

This will require some more thought, which is really dangerous.

Pat

I vote that you save it. Repaint the whole car. Heck, paint the 15" alloys Silverstone if they're not perfect. Charge a small fortune for the car. Someone will be willing to fork out the big bucks for a 1.8 Silverstone. I know, I don't get a vote ;-)

Chris

It is tempting to do that and keep it. I like the looks of the color and it is both one of the lightweight and easiest to modify miatas without running into emission problems like I would with anything after 1995.

For example, if my current powertrain were in my last miata, it would not pass inspection simply because there would no longer be a OBD-II connector. With my '91, they do the tailpipe sensor and it passes very clean. In 9 more years, it won't need emission testing at all unless they change the law again, but I don't think I will have it by then.

One big factor is that the Silverstone color truly seems close to invisible on certain streets and especially if the sun is at your back. It is much the same effect as the Porsche that James Dean was killed in; low, tiny and silver/gray to color match many road surfaces.

While the gray/silver is very appealing visually, it is not as visible to me as the brighter silver colors that Mazda has offered for this car.

The few times I have driven the Silverstone miata, it did seem like I was playing "avoid the other idiots" a lot more than I did in my blue miata or in my current red miata. The previous owner commented on it as well.

Pat

That's why the Silverstone cars are so nimble, they keep in better shape swerving around idiots! It's fun as long as your successful! Reminds me, last night my wife and I were following my daughter and her boyfriend who were driving my Black Miata (after dark) as some fool ran a stop sign and almost smashed them and a car coming from the other direction. I had the strangest reflex reaction, I instantly jammed in the brake and the clutch ........ in the automatic transmission Accord I was driving! Ya, hmmm, good thing nobody was right on my tail. Scary stuff.

Chris