Chris,
The normal procedure to remove a broken bolt or stud that still has enough
bolt sticking out of the block to get hold of is to use a lot of liquid
wrench or PB blaster (penetrating oils) to help free up the threads. Use
either a stud remover or vice grips to remove it. If it doesn't want to
budge, I usually apply some heat with a propane torch to the bolt and try
moving the bolt both ways (tighten and loosen) and it should finally come
out. I usually tap the broken stud with a hammer lightly also to help the
penetrating oil get into the threads. Many times it has taken a couple of
days of soaking with penetrating oil and heat and pounding before it breaks
loose. Since you have something to get hold of, you don't want to break it
off flush with the block and have to drill it and use an easy-out although
they work also.
I'm not sure what you mean by reverse threads as studs screw in the same way
as bolts (clockwise) and unscrew counter clockwise in most applications. I
just went through this on one of my kids cars that broke down while she was
on a camping trip. Car overheated and I had to replace the thermostat and
broke off one of the bolts taking the housing off. We ended up limping back
home with one side bolted on and the other with a pair of vice grips holding
the housing to the block where the broken bolt remained. It took a couple
of days of heating, pounding and lots of liquid wrench to get the bolt out
be it finally broke loose. Sometimes it just takes time for the penetrating
oil to do it's job.
Good luck
Dave 72 B
-----Original Message-----
From: Chris Rose <chris_rose@totalise.co.uk>
To: mgs@autox.team.net <mgs@autox.team.net>
Date: Friday, May 26, 2000 1:00 AM
Subject: New lister
>Hi all
>
>I have been lurking for around a month, but this is my first posting.
>
>I've got a quick question. I have recently aquired a 1963 MGB Roadster,
from
>my dad, who loving re-built it when I was a child and has had the car for
over
>20 years.
>
>Its mine because it has been standing in my dad's garage ever since he had
a
>motorbike accident and was unable to drive the car any more (pedals were
too
>heavy for his damaged knee) I couldn't bear to see the car go and so, when
he
>wanted to sell it, I took it from him.
>
>Its suffering all the normal problems of a car which has stood for a while,
>and I am working on those. However, I am not a mechanical genius, and have
a
>question.
>
>Whilst replacing some corroded cooling system pipes, one of the bolts which
>goes from the engine head and holds the thermostat housing in place sheared
>off while I was tightening the nut.
>
>I am assuming that this is not an integral part of the engine, and is
probably
>a bolt which uses a reverse thread and so can be replaced. However, could
>anyone advise me the best way to remove this bolt? (its broken about
halfway
>up, and so I don't think it was a case of me over tightening.) Should I try
>flattening off the top of the bolt and using a wrench to try and unscrew
it,
>or should I break it lower down and drill out the remaining part?
>
>Also, it was the final bolt I was trying to fasten and, despite the break,
the
>system does not appear to be leaking any water from the cooling system. Do
I
>risk driving the car around 30 miles to a trusted mechanic friend, and get
him
>to help me, or is this a job which I should be able to do myself?
>
>Any tips from anyone who has done this before themselves would be very much
>appreciated. What I want to try and avoid is damaging anything else whilst
>trying to fix this problem.
>
>Many thanks
>
>Chris Rose
>1963 MGB Roadster
>
>
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