How I may have killed my 740 (more info)

Fellow aficionados of the Brick

In an effort to remove the crank sensor from my 1990 740, I broke the mounting ear off the engine (transmission).

While tapping the sensor to rotate it in the mounting hole to free it up I hit the mounting ear.

Casting is designed with a very thin wall around the bore that the sensor fits in and hence broke directly across the bore. I am actually surprised at how thing the casting is.

Does anyone have any ideas about how to repair?

Pulling transmission is possible but certainly not convenient.

Has anyone else run across this?

All this an I hope the diagnosis of the original problem is correct.

No spark, no injectors, seemingingly open sensor (infinite resistance).

************************************ I forgot in the first post:

740 Non-Turbo

5 speed Regina/Rex systems ************************************

TIA

jimB

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Reply to
jimb
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I am just about to do a clutch job on my 99' V70 T5 and I plan to take the engine out instead of disconnecting the transmission in place. Judging from your experience this may be a good idea, right?

-Peter

jimb wrote:

Reply to
Peter Ziobrzynski

Unless I have a mistaken idea about how the piece is broken, it sounds like a job for JB Weld, a steel-filled epoxy. The repair area doesn't have to be exceptionally strong and won't exceed the 450F temperature rating of JB Weld.

There are a few considerations. The mating surfaces have to be scrupulously clean - use brake cleaner or alcohol. When the epoxy is applied it will try to invade the threaded part of the casting; you should be prepared to deal with that. A tap would work, or if there isn't room to do that you can wax the threads of the crank sensor and run that in and back out before the epoxy sets.

The finished product is surprisingly strong.

Mike

Reply to
Michael Pardee

Since the two screws that will hold the new bracket in place are concealed by the bell housing, the only way to replace it is to R&R the transmission. :-(.

Bob

Reply to
User

Hmm that could be a little tricky. Can you drill a hole through the broken piece on each side straight into metal still on the engine? If you can do that, then tap out the holes in the engine and ream the ones in the broken piece a bit larger you could screw it back on.

Reply to
James Sweet

On Wed, 03 May 2006 16:08:38 -0600, Peter Ziobrzynski

totally different car so I couldn't say.

I was working on the ignition and did something hasty.

this is an in-line drive car.

jimB

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Reply to
jimb

I held my camera behind the engine and took some pictures.

I see that the bell-housing has a relief for the nuts that hold the bracket.

I assume that you are telling me that there isn't enough room to get the nuts and bracket off as I had hoped?

TIA

jimB

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Reply to
jimb

Yup. Wanna see the t-shirt?

Bob

Reply to
User

I was thinking of just pulling the transmission back by a bit.

Put some longer bolts in a couple of the holes to keep everything lined up.

I am a designer and I was amazed at how crappy the part is. Also how fused the sensor was in the hole.

Maybe JB Weld with a reinforcing plate is the answer.

TIA

jimB

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Reply to
jimb

thanks for the tip!

I had never heard of JB Weld; you're the second person to suggest it.

sensor is not threaded in so it shouldn't be an issue.

jimB

-------------------------------------------- JimB

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Reply to
jimb

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