Dear Gods of MT.Net,

I have recently found out for the past ~2000 miles I've been running the engine -extremely- retarded (The timing belt may be a tooth off, checking it out in-depth Saturday). And yes, I am preparing for the Gods of MT.net to come in here and rightfully mock me for being retarded enough to not realize it until now. As it's my first piston engine I've ever worked on though, I knew I would be prone to going full retard at times - trusted the mechanic who changed the timing belt 100%, and well, it may have came back to bite me.

However, and onto my question: Is there any chance of engine damage? I've been searching like hell on this, way past my bed time even, and I am unable to find anything on this. The major concern I've been able to find seems to be overheating on non-interference engines, with the only real chances for damage beyond that on interference engines.

I'll be fixing the timing issue promptly.

 

I only trust me to do things right on my cars. Did you alter the CAS sensor position? If not, put a timing light on it and see what's going on.

Just pop the valve cover off and have a look. I seriously doubt you damaged anything especially if you have the stock head deck-height.

 

the real question is whether the miata has a non-interferring engine
I understand that is the case for the 1990-2005 engines

 

The consensus is that a stock engine, with a stock deck-height head is non-interference. I have Supertech pistons and a twice-decked head...I bet it's no longer interference-free. If you really want to know, position an intake valve at its lowest point and spin the crank with a little plasticine between the two.

 

Stock or even a .030" shave with stock 9:1 pistons is non interference, from personal experience. Also a FWD bp timing belt can be changed in <30min at the side of the road with the tools we all happen to have in the car, dunno about time to complete on a RWD one.

 

its definitely not that difficult, but I can't say I carry I breaker bar around with me in the car. good luck breaking the damper 21mm bolt off with a 1/2 wrench socket wrench, or an open-ended.

 

Thanks guys! You have been a tremendous help and a huge load off my mind!

Lesson learned :(. I only trust me to do work on my RX7s, but the timing stuff isn't something that exists on rotaries. Well, it does, but the rotary analogue has little relevance to piston timing.

No changes to the CAS sensor that I know of, and I'll definitely do that this weekend.

Will do. Thank you Hustler!

 

FYI as I stated earlier I've not changed a rwd bp timing belt but IIRC a fwd one did not require the crank bolt's removal. Cam swaps (on miatae) I've done haven't required it either.

That said the bolt removal may well be the correct method though.

 

You might be able to, I guess you could try to finagle the belt in from under the dampener.

And you wouldn't need to break the crank bolt to replace a cam... (now a cam bolt...that makes sense )

 

Just did my timing belt and there was no way to fit the belt under the dampener.

 

1.6 short nose cranks do not need the 21mm bolts removed to change the timing belt. Long nose 1.6 and the 1.8 engines need the bolt removed to get the timing belt off.

 

Okay, I am having an absolute nightmare getting the timing right.

Dragged in a relative yesterday who is the best mechanic I know, and we had a serious headache getting everything in the timing lined up perfectly. We stopped with what was "close enough" after following the FSM exactly.

When we tried to start it yesterday, he says that it sounds "Too advanced" to him. Video will come soon on it (With audio!) as soon as Youtube stops with their dick-dick-dickery on conversion.

 

where is video? I can pretty much tell you if your timing is correct with a couple of good pictures. Assuming the crank is positioned correctly, take a few pictures of the two cam gears and hopefully from a prespective that is not biased to either.

 

Got it fixed. Took two full Sundays with our dicking around, but we got it working correctly.

Shorthand: We had to repeatedly set the timing untill we finally got it right. Last time it ran it ran awesomely.

 

glad to hear, sorry I missed that message then. timing is so easy once you figure out the teeth counting trick and a picture of the two timing marks. hell you can do it without the timing marks period.

 

Coould I get you to elaborate on these? It sounds a whole lot freaking easier than our "Constantly reset belt untill everything lines up right 2 days later" method.

 

count the number of teeth between the two cam gears. Start the top notch on one and count to the top notch on the other. It needs to be 19 teeth exactly. Unless you are off by 1 notch on each gear, your timing will be correct.

If you are off by 1 notch on each gear its pretty fuggin obvious, but if it isn't obvious, just poke yourself in the eye with a ***** and you might see better.

 

 

yes sir. good picture, 19 teeth, and the timing marks are lined up.

 

This tool is going to make the job stupid easy from now on.