Yesterday I replaced the crank sensor on my 245. Now, I'm not an expert with 40+ years of wrenching experience, but I consider myself pretty mechanically adept. I've swapped transmissions & rebuilt engines, etc.

I'd read about how weak this bracket is, so I was careful when working on it and happy when I got the old sensor out without breaking anything. Before putting in the new sensor I put a little silicone lube on the outside of the barrel, cleaned up the threads on the bolt with a die and put antiseize on it before bolting it back.

Whelp, it broke as I tightened the bolt. Maybe I had it cross threaded. I was doing it all by feel, so who knows? It's in the car, and the car runs. Everything is snug, but I figure it's only a matter of time (or temperature) before it wiggles itself loose.

So now I'm on the hunt for one or two spare brackets, but I can't help wonder:
Why are these so flimsy?
Why isn't anyone making sturdier replacements?
Why not make them out of steel, will it interfere with the magnetic signal? If so, why not copper, or even just a thicker piece of aluminum?

I keep a broken one on my dash. Such fond memories.

the bracket presents no problems to a careful mechanic.
the real trouble ensue when trying to remove this sensor from a poorly kept 240.
a 240 where the valve cover has been leaking for X years and the owner is to indifferent or to stupid to replace it.

all the oil weeps down the back onto the sensor where it combines with road grime to make cement.

in those situations luck as much as anything else is needed.

for the other 98 out of 100 times the bracket is more than strong enough.

my take on the bracket fitness comes down to this: if the owner is a slob caring for the car maybe you get lucky maybe you don't.

Well, the issue with mine wasn't getting the old sensor out, it was putting the new one in. The old one slid right out (and I'd wager that it was original, with 270K+ miles on it, but I can't look for the stripe on the wire because the shielding is completely gone).

I ran into problems when I bolted the new one in, even after cleaning the threads on the bolt, cleaning the mount as well as I could, and lubing everything. I suspect it's possible that I cross threaded the bolt into the bracket since I was struggling to get my hands in there, or that I simply turned it a quarter turn too far. Whatever happened, the bracket gave up without any sort of a fight.

I've seen a few broken, a couple of my own. I replaced one without pulling the trans completely out but now I pull the trans & replace the rear main seal too.

I thought they were some kind of pot metal, not even aluminum.

Why so flimsy? Even 240 engineers didn't think through all of the effects of time, salt, corrosion, wear. The rocker drains, blower motor, trans lines also come to mind.

I had a motor-trans unit out - on a work cart - last year and still couldn't loosen the CPS without several daily applications of good penetrating oil over a couple of weeks.
--
240 drivers / parts cars - JH, Ohio

First answer would be because they could.

They justify their reasoning by saying, to themselves, it's a static part!

There is no pressure to push it up or down and no lateral forces applied to it from any direction while in use.
It a slip fit when installed, under factory assembling conditions. The thoughts about extra strength beyond molding it and releasing it from a mold becomes a done deal!

Be thankful that they did not use a internal snap-in type retaining ring. You know those with those tiny little holes in the ears.
Imagine trying to see down there with a extra long pair pin pliers...oh did I mention something about engine oil crud around that hole too!

I often wondered about the other 359 degrees of the flywheel circle, as in, other wide open places to locate that thing?

Guess their thoughts were only about being straight up and down with the Pistons and no mathematics involved?
Not whether they would be ending up in a pinch spot or behind something else?

Phil

The Volvo factory service book require transmission removal to replace the crank position sensor.

This task is made many, many, many time worse if you have failed, failing, or cheap and failing (sagging) motor mounts and transmission mount.

I use a scissor jack, with a piece of wood between it and the firewall, and the other end of the jack braced on the rear of the number four exhaust manifold runner.

Open the jack to pull the engine forward gradually.

You want clearance so that your (usually) 3/8" socket drive extension reach the top of the bolt straight on from the top rear of the engine. Use a 10 mm hex bolt. A little butyl rubber or a 10 mm hex socket with magnet load to lift the engine position sensor retaining bolt and flat washer up.

Keep you finger on the sensor end so you do not lose the flat washer or bolt.

With draw the failed engine position (or crank) sensor.

Reinstallation is the reverse of removal. By finger or socket, re-thread the bolt, and apply appropriate torque.

Usually, most used RWD do not care for their used Volvos. Motor mounts are sagging or are worse.

Most will impatiently try to remove the hardware with the 3/8" extensions at such an angle as to place great stress on the crank position sensor bracket.

A prior owner or mechanic may have replaced the CPS once before, distressing the CPS retainer bracket.

So, don't be too hard on yourself.

Repairing the broken CPS bracket may require transmission removal to repair it. Usually a weld is required to restore the bracket position, I believe.

Hope that helps.

cheers,

dud.
--
NEVER MADE IN CHINA

"Usually a weld is required to restore the bracket position"

Hrmm. I wonder of welding more material on would not only fix the bracket, but make it stronger. Even if it ends up being much bigger, the bellhousing is soft enough that the notch can be enlarged with just a hand file.

I should find a good welder nearby...

Why exactly? Why put it in at all? Its a pos design for sure starting in 89.