Oil pan sealing. Stripped bolt holes
 

I'm at the point in my build that I'm installing the oil pan. I have a brand new Mazda oil pan and a Garfinkle oil pan brace I'm installing. I made my first attempt tonight, and I made the mistake of not cleaning out the bolt holes with a tap first and ended up stripping a few of the bolt holes (good thing I didn't crack the housings). I'm going to try to put a helicoil in those holes. What are the bolt sizes that they use? Is it a M6x1.00? I'm thinking about also using a Moroso stud kit instead of the bolts included in the Garfinkle brace kit.

Due to the expermiental nature of most of my engines, i've taken it apart eleven, yes eleven times. over the course i've cross threaded a few myself. what i have done is drilled and tapped the hole. use a M8x1.25 bolt to replace the little guy, and i've not had any issues. just make sure you don't drill too far down or you'll hit the coolant passage.

Yes, M6x1.0

I ended up using a few helicoils in the front cover on my new engine. Most of the holes were already stripped when I received the engine.

Helicoils are generally stronger than the original threads anyway.

If installed properly, but for this application I don't really see any cause for concern using a helicoil.

I didn't realize this was such a common issue, I didn't have any issues installing my excessive pan. Are you guys torquing the bolts to spec or just giving it the ole good-n-tight treatment? torque spec on those bolts is not very much at all.

I beleive torque spec is 6 ft-lbs, basically a hand tighten not even a wrench tighten.

Spec is M6*1. I had seen somewhere M6*1.5 but using my caliper 5.98mm and using the thread gauge it is 1.0.

I torqued all mine to spec. The problem was the second hand front cover that came with pre-stripped holes. lol

I just went ahead and helicoiled every oil pan hole in the front cover because none of the threads looked healthy. The threads in my brand new housings were great! :)

M6 x 1.0

This is the reason we supply a stud kit and nuts with our brace instead of bolts.

Back from the dead...

Is this possible with the motor in the car?

Yes, it is a pain but possible. I have done it twice. (undue all the things preventing the engine from lifting up). undue the exhaust, engine mounts, intercooler piping, intake, etc. Place a jackstand under the transmission, use some blocks of wood to distribute the load better and also as a spacer to lift the engine up. Lift the engine up and be ready for some crappiness on your back. I did it without lowering the subframe as well;)

I recommend getting a tap to chase every single hole and ensure they are clean. I would then install studs in every single one, I even chased and put studs in the engine mounts. I used import grey RTV for the gasket from right stuff.