Stuck Bolt

Calling all auto mechanics! I’m slooowly overhauling the cooling system on my '91 Ford F-150 and I broke a mounting bolt on the water pump. The pump has been removed but the stub of the bolt is stuck (rusted) in the timing chain cover. Any standard (or non-standard) methods for dealing with this?

The only thing I’ve tried so far is to put a ton of WD-40 on it and try to turn it with a pair of pliers. It sticks out about half an inch and I’ve got maybe eight to ten inches of clearance in front (where the fan and radiator used to sit) and plenty of room on the sides.

“If you had manifested fatigue upon noticing that you had been an ass, that would have been logical, that would have been rational; whereas it seems to me that to manifest surprise was to be again an ass.”
Mark Twain
Personal Recollections of Joan of Arc

I remember something called a screw extractor from my dim past. Here’s a link that will show you what they are. They are probably available at most hardware stores.
http://www.drillout.com/drillout/

Not bad, 8 minutes.


“The problem with the world is that everyone is a few drinks behind.” - Humphrey Bogart

File each side square, use a lock wrench to grab it & turn. If it wont, use a torch on it, that always works, the heat causes it to expand & frees it.

There’s a tool called an “Easy Out” made for this purpose. Check with your auto parts dealer. As mentioned above though, heat is your best bet.

Just remember the ‘Right Hand Rule’ when you unscrew it… < ducking >

Thanks for the tips. I will try to find a screw extractor on my way home.

As to the heat suggestion – forgive me for stating the obvious but I’m supposed to heat the part it’s stuck into, not the bolt, right? I’m more than a little leery about bringing a heat source into the engine compartment (fuel lines, etc.) but if I do I’d sure like to heat the right thing.

Finally, DS – it’s “leftie loosie” and “rightie tightie”, right?

Again, thanks. I’ll let you know how it comes out. (No pun intended.)

“If you had manifested fatigue upon noticing that you had been an ass, that would have been logical, that would have been rational; whereas it seems to me that to manifest surprise was to be again an ass.”
Mark Twain
Personal Recollections of Joan of Arc

I once got a bolt that had rusted into place unstuck the really hard way, by drilling the bolt out. I started with my smallest bit and worked my way up, until there was barely enough of the bolt left to hold onto the threads. What was left of the bolt started spinning with the drill bit. It wasn’t pretty, and created lots of debris through.

You’ll need to drill it for the easy-out or screw extracter anyway. Make sure you start with a pointed punch at the center of what remains of the bolt. That way the drill won’t wander and bugger the surrounding area.

I’m with Handy on this one. Screw extractors are your only option if the bolt is @ or below the surface, but if any sticks out, try easier things first. Vise-grips locked on REALLY tight would be the first thing I would try.
If you do have to torch it, heat the bolt itself rather than the casting (counter-intuitive, I know, but heat conducts so well in the casting that it will take forever otherwise).

I never have been able to reconcile my materials-engineering courses with a youth spent fixing forklift trucks…

If you need to remove a frozen NUT, heat it evenly and the expansion will free it.

It’s less obvious when you have a stud or bolt. Won’t the expansion of the threaded seat cause it’s inner diameter to shrink, while the bolt expands… and makes it tighter?

It always seemed to me that the most important use of heat with rusted or frozen fasteners was to cause the rust inside the threads to fracture and become powdery. That’s what they always looked like coming out.


Hot laboratory glassware looks just like cold laboratory glassware.

Close, Roachman. Actually, it’s probably not rust though. I’ll bet (in this case anyway) that some coolant leaked into the threads from the inside and has been cooking there for 9 years (could be cooked oil, or some idiot may have used Loc-tite on the bolt). Anyway, heat does alter all these substances enough to get the bolts loose. I doubt physical expansion is as much of a factor (if I’m wrong here, somebody please correct me).

Pluto, when you put in the new bolts (IMHO you should always replace factory fasteners w/ grade 8 or better) coat the threads w/ silicone. You can get Permatex @ the parts store, but the $1.99 caulking tube size from Wal-mart works just as well. This should prevent the same problem if (god forbid) you should ever have to do this job again. Don’t use any kind of Loc-tite on anything you may want to remove someday (or where torque is a factor).

DS, You are wise to duck. The Great RHR Debate is not remembered fondly in some parts. :wink:

The bolt is unstuck!

Thanks again to one and all for the good advice. Kind of an anticlimax but it came out with just a pair of pliers – I guess I had to give the WD-40 time to work. Looks like it was just rust after all.

So I should have the water pump back on by tomorrow and then all the stuff I had to take off to get to the water pump and then, finally, I can put in the new radiator, which is where this whole thing started.

All told the whole thing will cost me about $400 in parts and replacement fluids (and one replacement bolt!) and it should run like an eight-day watch now. I’ve been kind of nursing it along (it’s got 100,000 miles) because I hate car payments more than I hate paying for repairs.

Next week – new tires!!

“If you had manifested fatigue upon noticing that you had been an ass, that would have been logical, that would have been rational; whereas it seems to me that to manifest surprise was to be again an ass.”
Mark Twain
Personal Recollections of Joan of Arc

WD-40 works well ifyou use it right. Sprinkle like holy water & hit with a hammer, whatever it is you want to turn.

A product called Liquid Wrench is the best for loosing rusted bolts. It will take several minutes for the compound to work.

It’s less obvious when you have a stud or bolt. Won’t the expansion of the threaded seat cause it’s inner diameter to shrink, while the bolt expands… and makes it tighter?

No. Assuming that the coefficient of expansion with heat of the seat material is higher than that of the bolt, the hole actually will get larger while the bolt will get larger by not as much with the application of heat.

Roachman:

Actually, the inner diameter expands with an increase in temperature, just as the outer diameter does. Although the fit may or may not be tighter with an increase in temperature, depending on the bolt and housing materials and, as a result, how much the housing inner diameter expands with respect to the bolt diameter.

Ah hell, Centerline already answered it. I need to work on my attenti… hey, look! There’s a jackrabbit hopping around outside!

Pluto, if you are looking for any recommendations on tires, I suggest the round ones.


“The problem with the world is that everyone is a few drinks behind.” - Humphrey Bogart

DS is trying to convince us that lawyers are as good at unscrewing things as they are at screwing them up?

Ray