Hi everyone.
I have recently purchased a 1979 series 1 RX7. I bought some parts today so that and my first job was to do an oil change. When I went to remove the plug I rounded it off. I have filed down 2 faces, tried multi grips but the plug is stuck. I was going to mig weld a spanner to the nut but I was worried about an explosion or electrical damage.
Any advice will be greatly appreciated.
thanks
pete

 

there are sockets you can buy that have sharp teeth you will kill the bolt but its a easey find at most junkyards."pocket item no charge"

i brought myn at sear for llike 10bucks

 

Yup.

A large easy-out is about the only way. I work at a shop that does LOTS of oil changes, so we see this all the time.

The drain plugs are also easily available at any auto parts store for chump change.

 

If you've filed down two faces, file just enough off of the other sides so you can hammer on a socket the next size down. If you can put it on with your hand, this won't work....you have to hammer (not too hard, of course...) the socket onto the plug...it should come right off with an impact hammer...if you use a conventional wrench, do it as a jerk, DON'T do it slowly..

 

Try a pipe wrench. They grip and hold better than vise pliers.

 

Thanks for the advice everyone. I will try the suggestions outlined above and let you know how it goes.

 

I'm going to have to disagree with the jerk statement. I had a stud cap pop off of one of my studs, and the way that I fixed it was hammering back on the cap, and using a breaker bar and slowly and EVENLY applying pressure to the stud, and it came out. If you jerk on it, you're instantly loading the bolt with torque, and if the material's microstructure is already damaged, it won't hold the instant torque.

I'd have to say find yourself some AeroKroil and soak the hell out of it. Hammer on a socket and SLOWLY and EVENLY apply torque to the bolt. It should slowly start to move, and eventually come out. If you can't get a socket hammered on it, use vice grips and make sure that they are really tight on the plug, and it should come off.

 

i still think the easey out sockets work better why risk wrecking a good socket.
plus more tools is allways better

 

Metwrench baby!

Love em'.
Im super careful to never lose any of my set,which Ive had for almost 10 years now.

 

I have butchered 1 socket by grinding the bevelled section off it. I have purchased a new sump plug and I have also borrowed a couple of sets of "pipe wrenches" which I am going to try these next weekend.
One thing which I did note was the aluminium washer, I have had problems with these binding super tight over the years. I will be interested to see what this looks like when I finally get the plug out.
Thanks agin for all the excellent advice.
Regards
pete

 

I think a pipe wrench, carefully positioned and turned, is you best bet. It should clinch when you supply pressure, not slip, even on a smooth surface (like a pipe).

The last oil drain plug I bought had a teflon washer instead of aluminum, I'd never seen that before but it seems to work fine, tightens and loosens a little more smoothly.

 

C'mon, maihn....this is a DRAIN PLUG. You need to JERK because it's frozen. Why do you think impact hammer wrenches work so well on really hard fasteners? For that matter, why do you think that hammering a frozen bolt BEFORE you try to get it off again works 80% of the time? APPLIED ENERGY. When you understand that principle, it becomes clear why the 'jerk' is necessary. You're right about jerking and STUDS and possible damage thereof, you're wrong here, simple as that...I've been doing this for close to thirty years and know what works for what particular problem.