'99 Miata - Not My Problem

Searching miata keyway repair brings up lots of hits including ones here.  

In reply to Patrick :

I'm reading now. It looks like the damage is less than what some others have repaired. I hate to send a car out there that's a potential time bomb. Not really my thing as a mechanic. 

Too early to say LS swap?

So the keyway thing isn't just an early NA issue?

Stampie said:

Too early to say LS swap?

It's currently being discussed. Probably a great candidate, but the owner isn't sure that's what he wants out of life. I'd probably attack the project just for the chance to build something cool without spending my own dollars to do it even though I'm not exactly swimming in spare hours. 

Floating Doc said:

So the keyway thing isn't just an early NA issue?

The keyway thing happens if you don't torque the crank bolt correctly.  Woodruff keys are for alignment, they aren't intended to take torque loads.

The visible bits of that keyway actually don't look too bad.  It's probably a reasonable candidate for the "loc-tite liquid metal" fix.

That exhaust cam sealing surface is definitely going to leak.  I have seen much smaller scratches leak heavily.

Fortunately, there is a Fix.  Repair sleeves (Speedi-Sleeves?) can be pressed on the end of the cam.  They are kind of a pain to install until you get the knack for whacking them on.  Must install straight and true or they will kink.

I had to install four of them on a Subaru once since someone used the "gouge the heck out of the camshaft" method of seal removal.  That engine had smaller scratches than that, and after I removed the timing covers, I could actually watch the oil trickling out of the seal area with the engine running.

In reply to Knurled. :

Thanks for the lead. If I'm going to do it, I might as well do it right I suppose. Crap. I'll see what I can dig up. 

Edit: Found it! That doesn't look toooooo hard. 

Sorry I missed this the first time around, it landed right in the middle of offline vacation time.

What you're looking for is the Loctite Fix. Developed by actual Loctite engineers, not some guy goofing around at NAPA. It works. Get those parts off and we'll have a look at what's going on.

There are easier ways to check the cam timing than counting teeth or looking for marks on the front of the engine, but we'll get to that later The breaker bar/starter method of banging the front bolt off is totally legit.

Alternately, find a 2001-05 bottom end and bolt the existing head on top. It'll get a compression bump and all the sensors will work.

In reply to Stampie :

If money was no object, maybe....... But I live in a financial reality and I just moved 300 miles and I'm still trying to get settled and deal with my new car payment. 

Right now getting it all apart and make the best decision on fix or replace with other NB miata bottom end looks to be the most likely candidate. 

In reply to spacecadet :

From the replies above it doesn't seem that hard. Looks like fixing it is the way to go. 

Moot point now. The timing pulley was stuck. Really stuck. I tapped and pried and tapped and pried and eventually got the pry bar in the wrong spot and cracked the block behind the pulley. So now it IS my problem. 

Yay for being stupid and impatient. Pretty sure I just bought a Miata. 

That's the oil pump, not the block. So, not great but still better than what you're looking at.

I'm looking at that broken key. I'm thinking that what happened here was that the timing belt pulley is well attached to the crank but all the other bits were able to spin. Including the trigger wheel for the crank sensor, leading to much wrongness in the ignition timing. You can also see some wear on the face of the teeth in the pic. Loose crank bolt, too much torque on the key? Or maybe it was recently reassembled with a key from a short-nose engine instead of the correct long nose?

That's just the oil pump not the block.  You just made a little more work for yourself.

Treed by Keith!  Not only was he quicker out of the hole but I think he's got a point on the key as well.  It doesn't look split in the picture.

In reply to Keith Tanner :

Holy crap. I didn't realize that's what was going on. 

So from here I pull the motor and take the crank out the bottom and then try and get things apart? 

In related news, I sent Mrs. Deuce an email telling her that I just bought a broken Miata. She says "at least you still have $18 in your challenge budget." I love her so much. 

In reply to APEowner :

Yes, the key is broken and half is still in there. Probably why things are properly stuck, yes? 

This doesn't exactly help my opinion of Miatas. 

Two main options.

1) Fix. Start by continuing to pry. You've already cracked the oil pump, so don't worry about it It's easier to pull these things off if you pull on both sides at the same time, either with a puller or with a pair of pry bars. Once it's apart, you inspect the keyway (I think it's okay), replace that crank pulley and oil pump, then reassemble. Of course, to change the pump you're going to have to drop the pan, so then you start looking at bearings, and, and, and..

2) Replace. Grab a good shortblock and bung it in. Here are your options, assuming you drop the current head on top:
- 1999-00. Direct replacement.
- 2001-05. Direct replacement. Higher compression = more fun. Main bearing support plate. High volume oil pump. Probably the best option.
-1996-97. Almost direct replacement. I think you'll have to swap out the crank sensor. Slightly lower compression.
-1994-95. No crank trigger or way to mount it. Either get creative or swap in a later oil pump. Trigger can be transferred over.

mazdeuce - Seth said:

In reply to APEowner :

Yes, the key is broken and half is still in there. Probably why things are properly stuck, yes? 

This doesn't exactly help my opinion of Miatas. 

So, someone screwed up the work on a 18 year old car and somehow it's the Miata's fault? Nothing's immune to bad wrenching. As the owner of a 1960's Cadillac, I can tell you that your characterization of the Miata as being as floppy as 60's car over bumps is way off. Let's concentrate on fixing the berkeleyup and not blaming the car.

Math story problem:

"If Seth's Miata engine is broken, and a meteorite happened to land on the R63, allowing Seth to buy it back at salvage pricing, how many sawzall blades would it take to fit the R63 engine into the Miata?"

Keith Tanner said:

mazdeuce - Seth said:

In reply to APEowner :

Yes, the key is broken and half is still in there. Probably why things are properly stuck, yes? 

This doesn't exactly help my opinion of Miatas. 

So, someone screwed up the work on a 18 year old car and somehow it's the Miata's fault? Nothing's immune to bad wrenching. As the owner of a 1960's Cadillac, I can tell you that your characterization of the Miata as being as floppy as 60's car over bumps is way off. Let's concentrate on fixing the berkeleyup and not blaming the car.

All tongue in cheek my friend.  I'm going to get a chance to really give a Miata a chance which I never have. I'm going to fix it and drive it and see if I like it or not. Maybe I'll fall in love. It's not the cars fault and I knew it was broken when it came here. In some ways it's good to find this problem because it explains pretty much all of the engine issues that the car was having. Maybe I'll get a chance to have a proper rallycross Miata yet. 

In reply to Motor_Mouth :

Don't worry about it. It's an old car that has had a bunch of people under the hood. It's pretty clear that I'm breaking it more than you ever did. 

Last thing for today, this is the backside of the front pulley piece. There is a groove on only one side (does this mean it was crooked? Wobbling?) and you can see where the teeth from the timing pulley were pretty hammered into the back in a couple of different spots. 

And not to offend Mazda purists, but is there a reason they did a two piece pulley and only had the crank nose go 1/3 of the way into the outer piece? Is this just one of those "It's a BP and we made it work everywhere for a long time" things? 

It's the oil pump that's cracked, I think.

About the small lip - think of it like a hubcentric wheel. There's a small lip that's there to center the part during assembly, but it's the clamping force of the lug nuts or crank bolt that holds it on. As long as you have the right torque on your fasteners, no problem. Let the fastener back off, and you get problems. Heck, you don't even need that center protrusion once it's installed. There's no need to make the crank nose go any further into the pulley.

I've not seen this particular failure before, although I have seen a number of Miata engines that have suffered from loose crank bolts after timing belt jobs. Looks like this was a fairly low-carnage failure, really. The crank pulley boss (the most recent picture) should probably be replaced and the alignment key as well, but nothing else got hurt before disassembly. The broken key is a victim of the problem and when it broke, that allowed the most obvious symptom to appear as the ignition timing became independent of the crank position. Looks like it slipped about 30*, which is not going to help the car run well.

So, did you buy a miata, or just an oil pump and gaskets?

Im with keith. Pull the drivetain, get it on a stand, fix whats broken, and send it on. 

In reply to Dusterbd13 :

That's the new plan. Wait out tomorrow's ice storm, pull the other Miata out of the garage, drag this Miata in, pull the motor, make another parts list, assembly is the reverse. 

I'm kind of kicking myself for this whole clever title thing. It's not going well.

Wait, other miata? Are you trying to be me, or are you trying to breed them?