7 replies to this topic

[DamonB06]

I spun a rod bearing on track a while back and quickly developed a pretty nice rod knock. Today I cut the filter open and found a whole bunch of bearing material. This is my first race car build and I am just looking for something to get me on track and be a mid packer. My question to you guys is, would you rebuild this motor or trash it and get a junkyard core?

Notice the huge chunk of bearing on the filter base, near one of the holes.



Gold Rush! The oil was full of golden flakes.

[snoozer]

Think that you might be better to look in the classified right here and see if one of those would work. Judging from the amount of metal there was in the filter you be looking at a full rebuild with a number of pricey parts, so maybe keep the old engine for parts.
Getting another engine will get you back on the track quicker and probably not cost as much as a rebuild if the block and/or head are even able to be redone.

[Ken SM94]

+1 Find a used motor with about 100k on it. $500 tops and you're back in the saddle.

Good luck

[dstevens]

A few hundred bucks will get you back up and running with used engine pretty quickly. Though I'd pull the damaged engine and give it a once over. It might be that you might need a crank turned and undersized bearing kits. It's about 50 for the bearings, about 50 for the machine work and another 40 or so for a head gasket if you need it and 10 for plastigauge and assembly lube.

[David S.]

Bringing this back from the dead...

I have a 1.6 Miata that spun a rod bearing. I'm going to call the machine shop tomorrow to schedule dropping it off to check everything out and see if it's worth rebuilding. If you've seen this before what do you think my chances are?

I'd like to redo this one rather than buy a craigslist engine. This one came from Craigslist and only lasted 3 weekends before it started knock knock knocking on heaven's door.

With that said, where do you buy your rebuild kits from? Is there much difference between OEM parts and aftermarket? I'm assuming I'm going to need oversized bearings if that makes a difference.

Anybody know how much of a difference boring it .010" and running oversized pistons would make? I run SSM and that is the only thing we're allowed to do to it.

Thanks in advance for any help. Inside the engine is new territory for me.

[Alberto]

The engine rebuild is doable if you have time, are patient and want the experience.  The FSM does a good job of guiding you through it.  My experiences rebuilding my 1.6 for SSM can be found here: http://blog.miatarac...assembling.html

 

I had to source a different crank during my rebuild since the timing keyway was worn on my engine (short nose crank).  A cleaning and micro polish by my machine shop was all it took to use the other crank.  I don't remember if I sourced the crank from a member of the local Miata club or craigslist...  

 

The machine shop I used offered to do the labor of putting the engine back together.  If you don't have time and there aren't any local builders that fit your budget, consider that.  Yelp and word of mouth are your friend there.

[Danica Davison]

so that is where you have been all this time damon   sorry to hear. Hope to see you on track again soon

[David S.]

Thanks, Alberto. I'll give your blog a look at lunch today. The machine shop will put it together for me but I'm thinking since the FSM is pretty detailed I'll give it a try myself. I've always wanted to put one together so what better time than now?