Help: Big oil line removal, broken exhaust stud.

SP2 · 10:38 PM

Hello, I have my engine out and I sort of ran into a few problems. I am a newbie mechanic, so forgive my stupidity. Here is on oil line off of my 81SC. I would like to remove this where it connects to the crankcase at the front passenger side of the engine. The photo shows two nuts. One is big and 36mm. The other is smaller and I can't get a wrench on it. Basic question, I know, but when you are looking at the big nut in the photo, do I turn it to the left? It's just that there are two nuts there and right now they both turn together and they don't feel right, so I thought I better ask.

The other photo shows my broken barrel nut exhaust stud. I made two mistakes. I heated all of the regular nuts cherry red and they all came off fine. The first mistake, I didn't let the entire barrel get red hot. Just the upper half was red. The other mistake was that I let it cool back down before I tried to remove it. It worked for the smaller nuts.

So for the other 5 barrel nuts I was more patient and got the entire nut red, then immediately torqued it off. It was so easy. I later used a torque wrench on a different bolt and figured it took only 30-40 N.m of force. I know I was using more than 3 times the force probably last night when I broke the nut. Damn. So how do I get the stud off. I have read and done the search, but my stud isn't flush with the port so I have something to grip with. I don't know how to weld, so welding a nut on isn't so readily available. My friend mentioned the SnapOn stud removal tool.

Thank you!

Walter_Middie · Walter_Middie's Garage

James,

No experts have answered yet so I will try. The oil line is removed by turning the big nut counterclockwise. It is a regular right hand thread, and turns the same way all the other screws turn. The smaller nut is a fitting that screws into the block, the big nut screws into the smaller fitting. You must remove the big nut first. You can get more leverage on the big nut if you can get a wrench on the smaller nut. Try a thin adjustable wrench on the small nut, and the correct wrench on the big nut. BP Blaster may help here also.

I removed all my exhaust studs using the double nut method, and very little heat (although red hot is good). Get two regular metric nuts and thread them both down onto the broken stud. Tighten the nuts against each other so they are jammed onto the stud. Now heat the stud and nuts red hot, then turn the nut closest to the head and this will unscrew the stud with the nuts still jammed on there. If this doesn't work, then try a stud removal tool. I bought an inexpensive one from Sears, and it worked OK - it just needs enough room to turn.

Hope everything works out for you.

Walt Fricke · 11-06-2006, 10:48 AM

Re: Oil line

Take the oil return tube off to make wrenching in this area easier. I see it is the nice collapsible kind already.

Grind an open end wrench down so it is thin enough to counterhold the case fitting. I forget just what size is needed here, but there will be an inch fractional size that will work fine and may be cheaper and more readily obtainable.

Having the case fitting come off with the larger oil line nut is not necessarily bad (when off you can easily enough grab the smaller flats and separate the two). But the worry is that you will damage the mating surfaces of the oil line or fitting or both in so doing: they look to be hemispherical, and seal by being clamped tightly together. If you can rotate the oil line with the big nut held in a fixed position with a wrench, I'd guess you are OK. But a good seal requires that these parts be clamped tighter than this.

Walt

SP2 · 11-06-2006, 12:21 PM

Rex and Walt,

Thank you for the advice. Looks like I will take the oil return tubes out first. You guys are the experts I was hoping to hear from. I will give it a go tonight.

SP2 · 11-06-2006, 10:19 PM

Rex and Walt, the combination of your advice was exactly what I needed. Thanks again for your responses! I removed the nearby oil return tube. Then I was able to get my 32mm wrench on the little nut, and the 36mm on the big one. As you suggested, I stabilized the little one and turned off the big one. Off came the oil line. I noticed the oil line adapter, where it seals with the crankcase, had some green stuff in there. Hard as plastic. Is this loctite? I want to be sure and put this sealant on later so no oil leaks.

Walt Fricke · 11-07-2006, 04:11 PM

Yep - looks like the green sleeve retainer Loctite. Notice it didn't do its job (lock the adapter to the case). I'm not sure you need anything here - there is a sealing ring to keep the oil where it belongs.

Walt (who is a fan of green Loctite anyway)

JWPATE · 11-07-2006, 06:34 PM

Walt, I noticed the same green loctite on both the oil flange fittings, during my recent engine teardown. Seems to be what they used at the factory, even though the manual advises the red 270 loctite when refitting.
The snap-on stud removal tool is great, but you will have to order and wait, or go find a snap-on truck. If that broken stud is the only one you need to remove, it looks to have plenty of length remaining to use channel locks, vice-grips, pipe wrench or what have you. The stud is scrap anyway. Those nice snap-on removal tools are worth it because they do not destroy the threads, on studs which will be reused.
James

A930Rocket · 11-08-2006, 03:59 PM

You may want to get the cheaper version of the Snap-On stud remover if you are not going to reuse the stud and from the looks of them, I wouldn't. It fits a variety of studs and simply slips over the stud. As you turn it CCW, it tightens on the stud and backs it out.

You also may want to use an impact to zip it out quickly vs slowly turning it out. They seem to come out in one piece better. Also, soak it in lots of PB Blaster for days before you try to remove them.