Psychic Wednesday???

Some people are slow.

Some people eventually catch on.

Some people won't admit it though.

Some people will, that is when forced to.

Accidently tuned in to Montel and yep, Wednesday is psychic awright.

Now... What can one do about a crank pulley bolt that's snapped off?

No, I didn't do it!

Yes, I inherited the engine (which appears to be good otherwise on strip
down).

TIA

JT


(Dreading a trip to the machine shop...)

 

Shouldn't be a problem. Try drifting the remnant counter-clockwise with a
sharp drift and a hammer.

With the bolt head gone, all the torque is off the threads anyway,

 

Isn't this counter to the theory (among some of us) that
it's rust and debris etc. that result in the ridiculous
torque often required to break the pulley bolt free?

That is, I thought you for one strongly felt the pulley bolt
was not actually in tension to the tune of some 500 ft-lbs.
of torque (on some Hondas)?

I am not as optimistic that this will come out easily
without a lot of drilling.

 

This technique often works except for the fact that this engine while
not directly exposed to the weather sat in the car for nearly twelve
years in this condition.

BTW, when I swapped engines a couple of years ago, (I never noticed this
as I had no immediate plans for this engine), the head had been off
for the same amount of time and there was "some" rust in the two center
cylinders where the pistons were near their lower limit of travel. I
assumed the engine was stuck but when I removed the flywheel, I noticed
the damned thing turning. It would only do about 1/3 of a revolution due
to the rust buildup.

Anyway, I put the engine in the back shed encased in a tarp for later
activity. Yesterday was that day. It was such a nice day, I backed the
Studebaker P/U to the shed door, carried the engine out to the tailgate
and sanded (with #80 grit) down the rust in the two center cylinders.

Within forty-five minutes, I had it freed up and quite frankly, cannot
detect any cylinder damage. I was turning the crank via the flywheel
bolts when I noticed the broken bolt in front.

I am simply amazed at the elegant engineering that went into this engine
design and it's ease of access, etc.

Oh, All the pistons have a "impression" for either valve clearance or
damage from valve contact which may have been why the car was taken off
the road.

I'll be attempting the prick punch method of removing the bolt remains
this evening.

Have a good one!

JT

 

Well, yes and no.

From the factory, I would assume that the bolt is tightened to spec
which (to me) shouldn't be much more than 150 psi. I only tighten the
(much larger) bolt on my Studebakers to 75 psi and have never lost one.
Trash and debris would only be a factor if the bolt was removed and
re-installed carelessly after the car was delivered.

Not me - See above.

If it's gonna come out, it'll be this evening. If it doesn't, I'll let
the machine shop tackle it.

JT

 

What's your theory on why Honda automobile pulley bolts are
notoriously tight when it comes time to change the timing
belt?

What year and make is this Honda, anyway?

Be careful, darling older, smarter honda-luvin' brother.

 

at least SOME of the torque will no longer be needed,with compression gone
form the assembly.
(I'm not optimistic,either;it seems nothing is ever "easy" when working on
older cars.)

 

I'd have to think about it more. If it is debris, rust, heat
cycling, etc. that causes adhesion over time between the
male and female threads, it's a pseudo-torque that's been
applied to the bolt. It's like a bolt was tightened to spec
//and then// locktite somehow dripped on its threads. If the
head shears off, is the torque required to deal with the
locktite really going to be less? Not sure.

 

The engine is the original that was in the '83 Civic FE. If you recall,
I replaced it with a running motah out of an '81 DX but used all the '83
accessories and attachments.

If it's gonna come out, it will do so easy. Otherwise, the whole schmeer
will go to the machine shop next week.

JT

 

It always seems to be that last bolt or fasterner...

<grrrrr>

JT

 

Generally speaking, a bolt/screw that sheared because of over torquing
usually comes out pretty easy. The ol' prick punch method usually works
best and I strongly recommend to NEVER use an "easy out." If that
breaks, you're in deep doo doo...

JT

 

Ooh. That could complicate things.

However...an air chisel will still drive it around very nicely even if
corroded. Any garage with air tools should be able to do this for you.
Unless it's really caked up, the air chisel should spin it off in
seconds.

Check the crank bearings. Excessive wear will allow the pistons to
travel too far upwards.

IF the pistons are contacting the valves, the valves will almost
certainly be bent.

 

There's no "theory" involved.

The cause is simple embedment.

Not only have I been told this by engineers whose specialty is
fasteners, but HONDA SAYS SO, TOO:
http://www.tegger.com/hondafaq/misc/hsn_feb-93.pdf

 

We already went over this, and the guy was not absolutely
sure.

This only says two to three times the installation torque
may be required to remove the bolt, not why.

I am not rejecting the theory. I am saying I don't know for
sure the cause.

 

It twisted off deep in the recess and it was a "no go" with the
centerpunch technique. I'll drop the shaft off to the machine shop next
week.

I don't think so in this case as the engine had only 110K and there is
no detectable ridge at the top of the cylinders. In fact, even sanding
down the rust with 80 grit doesn't seem to hurt the cylinder walls.
That puppy might get by with a honing and new rings/rod bearings.

I have the head which was supposedly rebuilt. Maybe I should send you
some pix of the piston tops. I've never run into the valve/piston
fracas when a timing belt snaps.

JT

 

It says the reason is the bolt sticks to the crankshaft threads. That's
"embedment".

It's not a "theory", but established fact, and a well-known phenomenon.

 

Broke off too deep to be able to get a good run at it, I guess?

I'd like to see the recesses you mention.

I haven't, personally, either. I have personally known of two Honda
engines that suffered no damage when the belt broke (Civic and CR-V).

 

It's a little spooky for obvious reasons, but when I had trouble with an
alternator support bolt breaking off recessed in my really old Volvo (don't
ask) I had success epoxying a nut to the end of the bolt. I prepped the
location by spraying with brake cleaner. I put a dab of quick set epoxy
putty in the center of the nut and left it extending out a bit, then pressed
it into place and held it there a few minutes. I did let it set overnight
before putting a wrench on it, though. Easy does it!

Short of that you can try duct tape on the back of a socket to fit in the
hole, but I never got enough traction with that. Never tried a left-hand
drill.

Mike

 

Not so much that but it's not budging. I'm simply distorting what's
left even more.

In my earlier days, I would have found out exactly what the dimensions
of the shank minus thread were, got a drill bit slightly smaller and
attempted to drill it out and retap (clean the threads) myself. But I'm
far too lazy to do that now.

I suspect that the crank itself is fine and within tolerance for a new
set of standard bearings. I'll send a pix of the piston tops later today.

JT

(Now if this was the Studebaker group, I'd just post 'em right here..)