I posted here a few weeks ago with some questions about broken bolt removal. I had a bolt today broken off flush with the surface, and I used the suggestion of welding a washer on to it. I was going to weld a nut on after that, but first I tried vise grips on the washer, and the bolt spun right out. Linda took some photos for me that came out really well, sort of artistic-like, so I posted the links below.
Before I did the welding, I tried to drill the bolt for use an easy- out. Last time the drill went right in, and the easy-out worked fine. But this time the drill would not penetrate. I tried some new bits with no success. I'm wondering if I hardened the bolt by heating it with a torch and then spraying it with PB Blaster. I did this three times before drilling, and maybe it was like I oil quenched it? It doesn't seem possible, but those bits were not going in.
Here's the links. I have small images, and really big images for those of you who are bored or have fast connections.
3.5 > I posted here a few weeks ago with some questions about broken bolt
if you got it red hot you surely hardened it.
it could have just gotten work hardened by it getting torqued off or just got brittle from the environment it was in
a better, cheaper alternative to pb blaster is 50/50 atf/acetone (saw that on a jeep forum where people buy pbblaster by the pallet load) supposedly it had the best penetrating of all the big name oils on the market and was the cheapest.
-matt
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You can go over to my Ford dealer and help them with my car. At least one of their service techs is -- right now -- experiencing the joy of extracting half a timing belt idler pulley hold down bolt from the block of my 2000 Escort's engine. It's going to cost me over 10% of the price I paid for the car seven years ago, but I DON'T HAVE TO DO THE WORK! HAHAHAHAHAHAHAHA!
Before they give in and decided that they have to take the shroud off they have about 3" to work in -- taking the shroud off will give them 7 or so. I assume they have some clever low-profile drill, some _really hard_ left-hand drill bits, and more than one sort of bolt extractor.
I actually considered doing the job myself when I heard the price, but then I reviewed the fact that I'm actually busy right now*, and the risk inherent in extracting a grade 8 bolt from an aluminum block, and the cost of all the extractor gizmos, and the embarrassment when I go back to them to do the work anyway, and I decided to use my credit card as my tool of choice on this one.
(I'm finding that it's kind of fun to mention to these guys "oh, I don't do work on my own cars any more, it kind of lost it's appeal", because of the way they sigh and say "yea, we understand". I'm going to have to stop before they chuck my car in the river, though.)
Which has nothing to do with any short-term virtue on my part; there's some skill involved in getting myself set up to have loyal customers right now, but a hell of a lot of luck that my skills are still popular enough to get me by.
IMHO welding a washer then nut on a broken bolt is the easiest and first thing to do, and I only even consider drilling if welding is just not possible. As you discovered, the broken bolt very often comes right out with only a washer weld. After some practice and a couple of successful removals we all aquire confidence in this usually superior technique.
Similarly I almost always remove bearing races in housings by shrinking them with a weld bead rather than fooling around with pullers.
This task is easy to do by welding a washer on the broken bolt, and since it only needs an inch of rod to do the job requires much less clearance than any drill, and access does not even need to be straight. The aluminum block only means you do not need to be as worried about welding the bolt to surrounding iron.
un-needed?????
Think positive.
They say "yea, we understand" to your face, but I suspect their thoughts are less flattering.
I understand and agree that we all must choose our priorities and manage our time in the most profitable way, but you are paying them full dealer shop rate which I suspect is $80-115/hr in AFTER tax dollars? (net $120-175/hr + your travel time and costs to get your car to the shop, (unless the repair is deductible as a business expense then net cost is reduced)) which I suspect is more than your chargeout rate or net profit. Having someone else perform auto repair is IMHO usually an expensive self-indulgence.
In this case I would also ask who broke the bolt in the first place? ISTM that in addition to the cost of the labour and the marked up parts price, you are now also paying for their failure to properly remove the bolt without breaking it. IMHO a 9 year old engine bolt should not break when removal is required.
Please excuse any earlier comments that may be perceived as overly critical, as this was not my intent. As small businessmen we must constantly make decisions regarding how to best direct our most precious resource which is our time. In the long term your personal and business development and customer satisfaction will yield the greatest return on your investment of time and effort.
Tradesmen, trades hobbyists and self employed people tend to (often excessively) value self control and have little faith that others will complete required tasks properly and to our satisfaction. We also often think that we can do these tasks more cost effectively than others.
As an engineer and computer programmer, I suspect you will agree that the first time we do a task we are not really competent or cost effective, but that in addition to the value of the work actually performed, we receive as (tax free) profit the value of the learning and experience gained in the performance of the task.
Similarly we can seldom pay for out tools on the first job we do with them. I would prefer a better welder (DC) than a Tombstone (AC?) but the basic skill of a good tradesman is the ability to ' make do with what is available'. Lots of good work has been accomplished with simple Tombstone welders, you just need to understand, and work within, their limitations.
For most of us, automotive machinery is our second largest investment and expense, and one which we make throughout our lives. Some of us have found that great savings are possible by careful management of this expense and that performing mechanical repairs ourselves not only saves money but gives us a better understanding of the machinery and how to manage it in the most cost effective manner.
The total cost of personal time and TAXES which are payable when purchasing services is often not considered in a simple cost/benefit analysis, and the value of experience gained is often omitted from the benefit side of the equation. Similarly the full value of knowledge gained when performing work different to our main vocation is not always appreciated..
We do things ourselves not for the value of the job, but for the value of the experience.
For the benefit of those who have not done this, it only applies to outer bearing races, removed by shrinkage from inside a housing and NOT to those on a shaft. Those should be heated and removed while they are hot and expanded.
Could you expand on this please? Do you just run a nice "snot bead" on the inside and allow to cool? I'm assuming your talking tapered needle ones here where you can remove the inner.
Everyone is entitled to do as they wish. I rarely weld on outer races my logic is that in the process of upsetting the metal which is why it gets smaller when cool there are forces on the hole the bearing is in which might make that hole or bore looser than the interference fit it was machined for originally. This technique of using a mig bead is used by some mechanics on valve seats. The manual for the device usually instructs to cut out the old valve seat using some item for that purpose. Quite often the bearings will just fall out when the whole casting is warmed perhaps to somewhere around
300 degrees F. I have welded something to the inner race of a bearing (like a normal ball and cage type) to pull with and not worried about it. low spatter tig as there are often other bearings not getting removed nearby.
If your bearing is stainless and it's in an aluminum bore, that is a reasonable caution. Try freezing the bearing. Often it's not too difficult to get dry ice, and place some in or on the bearing to shrink it. If the rest of the case (or whatever) will fit in your oven, bake it all to about 250 - 300 degrees F. then use cold water directly on the bearing.
This page may help a little- it's guys talking shop about heating and cooling for bearing removal.
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It seems to be an artform, best learned by doing. Find some busted up piece of crap with a bearing in or on it and try out their freezer / propane torch ideas. I personally have a tiny bit of experience, and this seemed to work really well without disturbing the fit of the new bearing.
Many thanks Snag. I've just done a bearing in the camper with the old Mapp gas torch to warm the hub then drift and hammer method. Maybe I'll try this next time Remembering to put the new bearings in a baggie (I think that's what you guys call them) and in the freezer for a coupla hours/overnight. That makes it so much easier
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