So i removed my A/C, and i remembered seeing something in Splitime's buildup thread where Braineack pointed out he should put one of the bracket mount bolt back in or he will get a big mess..

My question is did you mean oil will leak out of that hole? because i lost that bolt

Anyone know the size and thread pitch of it so i can find another one so i dont loose all my oil?

here is the post im talking about, post #43 https://www.miataturbo.net/showthrea...t=10844&page=2

 

start the engine and see what i mean :gay:


if you look closely the bolt is actually onto the oil pump itself. it's pressurized behind it. I'd say a typical m8 or m10 will fit in there. dont you have a random bolts collection?

 

When I removed my A/C compressor and bracket, I didn't re-install any of the bolts that came out. That was over a year ago, and there's no oil gushing out the side of my block.

Perhaps the 1.8 blocks are different?

 

maybe im wrong, but i was fairly certain the forward facing bolt on the oil pump is under pressure.

 

i dunno, ill find one and put it in there just in case

 

is this 1 of the 4 long bolts attaching the a/c to the bracket, or the bracket to the block?

 

I didn't replace any bolts either, no oil leaks here.

 

I just found a random bolt to be honest.... It's 1 of 4 or 5 I believe that hold the pump. You can possibly get away without it... but i put it in for safety sake.

 

I am an utter moron. Disregard completely my last post on this thread.

I had previously interpreted this business of oil leaking if you don't replace the bolts to mean that oil was actually going to leak out of the bolt hole itself. I'd even gone so far as to run a cotton swab down into each bolt hole to check for the presence of oil and come up clean.

What I realized last night after looking at the pictures linked to here is that one of the bolts I'd removed when pulling the A/C bracket was also holding the oil pump housing onto the block. It's the one that goes into the front of the engine, not the ones that go into the side. I'd completely forgotten about that bolt.

I have marked up one of the images from the other thread below. When the bolt which is illustrated in green is not present, the mating surface between the oil pump and the block (roughly illustrated by a pink line) does not seal fully. And wouldn't you know it- there is in fact a tiny bit of oil seeping from that gap!



I did some measuring, and I believe that the correct bolt to use in this position is an M8-1.25 x 45mm. I'm going to pick one up at lunchtime, and I'll try installing it this evening.

 

so, how did it go, was it the right size bolt? i gotta get me one of those.

 

I didn't put that bolt back in at all and I've no oil leaks since last April.....well, none so far anyways.

 

Braineack is rarely wrong, but he is definitely wrong on this one. It is not "just some M8 bolt"; it MUST be a 45mm M8x1.25, just like Joe said. 40mm will strip the threads, and 50mm will bottom out before it is fully tight. I replaced that bolt with the aforementioned M8x1.25x45mm, and it has worked perfectly.

 

or a longer bolt + a couple washers. Worked for me.

 

The 45mm bolt fit perfectly. I cleaned up the trace of oil that was there, and we'll see how it goes.

 

I'm raising this one from the dead.

I'm down for "heavy" maintenance, and the damned oil weep from this area was one of the items on my list to fix. I thought it would be a simple matter of installing a bolt.

As luck would have it, a strong light and inspection mirror reveal that this bolt has broken off even with the iron block (i.e., the break is about where Joe's pink line is drawn). I'm guessing some gorilla (not me for a change) put in a too-long bolt and torqued on it until it sheared.

Would really like to get this fixed. Any downside to drilling and trying an easy out? Pretty sure I'm clear of oil and water passages with this bolt. Any other suggestions?

 

Only that you will then have half a broken bolt stuck in the block with half a broken EZ-out stuck in it.



I kid, though in all seriousness, I cannot recall ever actually succeeding at using a bolt extractor to extract a bolt.

 

I've had the exact same experiences with easy outs. I think I got one to work once, which only fueled the frequency and vigor with which I've broken them since.

In a moment of clarity while drinking coffee this AM, I came upon the obvious solution. Drill it and tap it. M8 x 1.25. Duh. My radiator and condensor are out and I've got great clearance. 5 minute job.

/end

 

Thanks for that illustration Joe. All this time I thought I've just been nursing a leaking front main.

 

I would also like to raise this thread from the dead, and apologize for doing so.

My bolt is also broken inside, way in the back where the M8x75mm shank has threads. All of the internal threads are blocked by the broken threaded piece, so I can’t even get a new bolt tightened on. It’s too deep inside for any of my extractors, and I’m afraid removing the turbo intercooler piping, AC, AC bracket, will still not let the extractor deep enough into it.

It’s been this way for 10yrs, just now noticing the lost bolt with a dirty left underside. everything else on the engine had been cleaned and sealed new. Just never saw this one.

just sealing the exit hole would prevent an outward leak, but the oil pump would not be tightened against the block/bracket without a full 75mm bolt, meaning everything else would still leak.

does anyone have any ideas?

 

As a professional mechanic, I often lose site of what a typical DIY'er is capable of, but if it helps, I'd be removing the AC compressor, bracket, and trying to extract the bolt with ~1" more access. I also have a ~$500 snap-on extractor set. I'd also prepare the customer for engine out service to properly remove the oil pan, oil pump, and remove the bolt. I can walk you through what my process would be, with ~$60 in cheap amazon tools. You get what you pay for, but these may do the job if that bolt isn't cross threaded or bottomed out.

That's a great time for a set of center punches:


Put the biggest one you can fit in the oil pump in, and smack it with a hammer. Then use reverse bits and an extractor set:


You can buy these separately, but just know what kind of force the extractor bits can handle. If you feel like it's about to snap, STOP. That's the #1 thing you're trying to avoid with a job like this. The extractors fit in these sockets: