Just a couple days ago I received a motor from UK motors for my 2001. I expected some rust, as this is why the cars were removed from the road, I believe. I didn't expect it to be as bad as it is. I can deal with cleaning and painting but I have concerns about the ac bracket holes. The motor never had ac and the threaded bolt holes for the bracket are super rusty. I was going to try and run a tap into them to see if there's enough metal to hold the bracket. I'll be doing that tomorrow. I believe that the size is m8x1.25. Can anybody confirm this size?
I also wondered what to do if they're too rusty to hold the bracket. Anybody have any ideas? I'm not real confident working with metal so that's the extent of my ideas. Doing away with ac is out of the question. The car is more of a daily and it's friggin hot as hell here for much of the ear.

 

If they're too rusty to clean up, you can enlarge the holes with a hand drill and install a helicoil or timesert. I prefer the latter.

 

I believe the AC bracket bolt holes are 10x1.25.

I would chase the threads and then try a bolt in the hole, using a torque wrench.
If you are able to tighten the bolt to, let's say, 40 - 45 lbs without drama, I would say they would hold.
Otherwise, a practical solution would be drilling and tapping the holes to accept 12 mm hardware.
I did this on a number of occasions, and the results were nothing short of perfect.

 

Wow, that is ugly.

I chased every thread on my block. I first sprayed a good rust penetrant and allowed it to soak for a while, then I ran a round brass bristled brush on my drill in the holes and cleared out debris with brake clean, followed by a thread chase with a bottom tap and another debris clear. With yours I would probably go through a few penetrant brush cycles and then carefully step up from a starter tap to a standard followed by a bottom tap.

Every hole is finished with protective lubricant.

GL!

P.S. IIRC there are a couple/few holes with a different pitch, like a 10-1.5. Can't remember which ones.

 

Taps for chasing are different to taps for cutting. You want to clean up, not remove metal. Ideally don’t use a tap intended for cutting a thread.

If you do decide to use a tap for cutting, use loctite on the bolt.

 

I would not use a tap for cutting threads either. Cheap way to make a thread chaser is to take a bolt and cut a few slots in it perpendicular to the threads. I would start with penetrating fluid and a brush, then follow up with the thread chaser.

But that block looks rough, I am pretty sure your balancer and front cover bolts are pretty messed up too. Good luck doing a timing belt job on that engine, I hope the threads in the oil pump for the cover are still usable. I hope you got a good price on that engine: here in Europe I would never give more than 250 dollars for an engine in that state.

 

DaWan beat me to it...

Yes, you do not need to invest in a tap set just to chase threads - even if they are stripped.
I just take a bolt of same thread and pitch, cut slots and quench it.
(Is that the correct word? I get it red hot and then dip in water to harden or temper the metal)

Stellar results every time.

 

Why not just strip it and send it to a machine shop to be hot tanked/cleaned?

 

I'd first off clean out the threads with a round wire brush, prob a brass one since it's got a bit more rigidity to clean out flakes.

Then yeah, try a bolt and see if it fits.

 

Pretty sure people are buying these overseas motors are for cheap runners, and most don't intend a rebuild before install. At least not before their initial install.

 

Put the motor in yesterday. Those threads actually cleaned right up. My friend had a tap and all was good to go.
I did buy it as a cheap replacement motor. I just don't have the skills or place to rebuild it myself. Local junkyard vvt motors have 130k and they want over a thousand dollars.
I was nervous about the long distance sale but the motor looked great inside, when we pulled the pan and runs flawlessly.