Hi everybody,

Well, I made a rookie mistake on my 1987 740T. I changed the oil in the gear box (which was way past due). I put the bottom 13 mm plug back in. Then, I tried to remove the top 13 mm plug, which was rounded a light bit. I couldn't break the plug free; so I thought, "No problem, I'll just bring out the vise grips." No go. The vise grip is just wearing away the brass nut. I tried a crescent wrench, pipe wrench, and vise grip again and again.

Any ideas? I'm thinking of drilling a hole and then using an EZ-out. But that EZ-out is hardened steel, and I suspect it will just eat right through the inside of that brass nut.

Before I drained the old oil, it was difficult to shift gears, even with the engine off. Now, with all the gear oil out, shifting is much easier.

But, I looked underneath the car and discovered I have a hydraulic clutch. Is there a way to adjust these? I see no adjusting nuts.

 

How about a photo of the fill plug.

My Volvo has an automatic but most hydraulic clutches are self adjusting. If it is not releasing you could try bleeding it. If that does not work you probably have a bad master or slave cylinder.

Lou

 

Thanks, Lou. Tried to upload the photo twice, but failed.

 

It's pretty rare to find a 740 T with a stick shift (like mine has). Bleeding is the first thing that came to mind before I read the second post by lleroyb. So I agree with him. A few notes on bleeding. On my car the clutch master cylinder "steals" fluid from the brake fluid resivour. So you just fill it there. On the actual bleeding process pumping the pedal is the best method from what I hear. And you want to push hard too to "blow" any clingy bubbles out. I'd start by pushing the pedal slowly while the assistant opens the bleeder. Once you know it's open punch the pedal to the floor. Once you hit floor, have your assistant close the bleeder. Once the bleeder is closed, let off the pedal. When you have good, clean bubble-free fluid flowing, I like to bleed it one more time a little differently. Push the pedal. Then the assistant opens the valve for a second and closes it before you get to the floor just to make sure any air at the end of the line is out (that might have gotten in there while the pedal was floored, before the assistant closed the valve). I just bleed a few brake systems recently and that pretty much what I found out worked best (tried a few different methods). The only difference with brake systems I crammed the pedal until it stopped and then asked the assistant to open the bleeder. You might know all of this already, but it may help some other reader.

About the plug, you could try heating the case around the plug with a propane torch, or maybe even the plug. I don't know how difficult it is to get to that plug, but I would try a socket with six-cornered (not the regular 12-cornered). Also, my boss had a socket set the was made kinda like an inside-out EZ-out. It would dig into the hex head near to the middle of the the sides rather that on the corners, which is where a regular socket grips (thus we have rounded corners). If all else fails, you could get a hack saw or circular cutting wheel on and angle grinder and solt the head on the plug, then take a hammer impact wrench with a slotted head and take it off that way. Those hammer impact wrenches do a good job. The hammer blow keeps it in the socket and powers the turning action.

Good luck with that plug.

 

Thanks Titan Joe. That plug is the big problem. Weather is turning iffy now; I'll get back to it in good weather.

 

I may have to chisel that plug out. There's not enough room to use a hammer impact wrench.