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Help. Wrench fragment fell deep into engine hole (photo)

Home Forums Stay Dirty Lounge Service and Repair Questions Answered Here Help. Wrench fragment fell deep into engine hole (photo)

This topic contains 7 replies, has 3 voices, and was last updated by Theo Theo 1 year ago.

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  • #894477

    Honda C35 engine. Crow foot wrench broke and piece fell deep into hole !

    Cronicle of the tragedy:

    Started out replacing valve cover rubber seal that was very slowly leaking oil onto exhaust…
    …In the process I noticed I had to replace the post shown by the yellow arrow because the nut threads had stipped and the cover bolt would not torque properly…

    Used a crow foot wrench (see photo insert) to remove the post. Crow foot wrench broke and piece fell in the hole shown by the orange arrow. …. Yes, I know…

    That hole is pretty deep, about 10″.
    Should I start looking for a replacement car? Or is there a way to remedy this?
    The car has 250k miles but was still running well.

    So some of my questions are:
    Q1. Where does that hole lead to? The crankshaft?
    I put a small dowel in the hole to measure its depth and it went down 10″ before finding an obstacle. Is it the crankshaft its hitting?
    Q2. Is there a way to get the wrench fragment out?
    I could get a borescope camera to help out.
    The wrench fragment is magnetic while most of the engine is not. That is an advantage as I could perhaps use a magnet attached to the camera.
    If the wrench fragment ended up in the crankshaft I could conceivably retrieve it by removing the oil pan (somewhat complicated because I have to remove wheel axle but will do it if it’s the only option)

Viewing 7 replies - 1 through 7 (of 7 total)
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  • #894478

    It’ll probably sit at the bottom of the oil pan forever and never cause trouble. Safer, however, to pull the pan.


    Thanks relative4. This is very valuable information.

    I will get a borescope with small camera and put it down the hole, see if I can find the piece. But I will probably not find it this way because, as you say, the broken wrench fragment likely ended up in the crankcase. But seems worth trying the borescope first.

    I looked at the oil pan and unfortunately removing the oil pan on that car is quite the job. The intermediate axle goes through the oil pan (see parts diagram). So reading the shop manual I’d have to remove ball joints and axles plus the differential. Worse, shop manual says I’d also have to remove three engine mounts which means I’d have to support the engine from the top with a hoist since I cannot put a floor jack under the pan. I don’t have en engine hoist. Or is there some other trick?

    Here is something interesting…
    Looking at the diagram below, if the broken wrench fragment made it into the crankcase, then it is likely sitting on top of that baffle plate marked #5 in the parts diagram. If the fragment is not sitting on the baffle plate yet then perhaps it will soon make its way there — as soon as there is some engine movement. I will first turn the engine by hand a few times if I decide to go that route.
    Now if/when the fragment makes it all the way to the bottom of the oil pan…
    …then I might have a chance to get it out through the oil drain hole. The fragment is only 6.5mm wide and the oil drain is a 12mm bolt, so the fragment should be able to pass through the oil drain.
    The oil pan is aluminum so if the fragment ends up at the bottom then using a strong magnet and dragging it on the bottom of the oil pan I might be able to direct the fragment towards the oil drain opening.
    Once I have the borescope I can also put the camera in the oil drain and may be able to see the fragment, in which case I may be able to pick it up with a small magnet attached to the camera.

    So, are you reasonably sure that this hole leads to the crankcase? (I guess once I get the borescope camera and put it down the hole I may be able to see where it ends up myself)


    Oh man, through the pan like a BMW? That sucks. I actually have the subframe off a 335xi right now. I hate that crap. What kind of car is it?
    Personally, I’d run the engine for a few minutes to get the piece off the baffle, then drain the oil like you suggested.
    If you end up tearing the whole thing apart, you use an engine support bar. They’re like $70 from Harbor Freight after 20% coupon and sales tax.


    Yes, unfortunately through the oil pan…

    Sorry I forgot to mention the car is a 2003 Acura RL. Has the C35A Honda engine. The C35A was apparently used on Acura RLs only from 1996 to 2004. Other smaller C engines were extensively used on Acuras (Legend, NSX) and some Honda Accords from late ’80s to early 2000s but I don’t know if the lesser displacement engines also had the axle through the oil pan.

    Actually, I can handle the axles, have done it before. It’s removing the engine mounts and supporing the engine that worry me. Never done that. Thanks for the engine support bar suggestion. Did not know such a thing existed.

    First let me get the borescope, gather some more information, or maybe even be extremely lucky and catch the piece that way. There is not much hurry trying to fix this, I have another car. But this Acura once belonged to now deceased family members, has been driven by the family for 253k miles and so has a lot of sentimental value. I would hate to cause its demise this way.

    Nightflyr *
    Richard Kirshy

    Just a thought …
    Might try fishing a magnetic pickup as far down the port as possible.
    Might get lucky and snag the piece of broken wrench.


    Thanks everyone.
    As a first step I ordered this endoscope:

    The endoscope comes with a little magnet attachment. Seems like a good thing to have anyway. Should arrive this weekend. Once I get it I will first scope down the port, who knows there’s a small chance the piece is still there somewhere accessible.
    Until then I will refrain from disturbing anything, just in case the piece is still precariously hanging somewhere accessible.

    I’ll post any progress…


    SUCCESS !!  I got the broken wrench fragment out.

    The borescope I posted came in and I used it to get the broken wrench fragment out.
    First I put the camera down the vent.
    The broken wrench fragment was still sitting at the bottom of the vent hole. It was sitting on top of the crankcase baffle plate(?) or is it the side of the engine block(?) or is it the side of the oil pan(?). See photo here .
    I just did not want the fragment to fall further down past that slit as I attempted to retrieve it.
    Here you can see the exploration video where I saw where the broken wrench fragment was sitting down at the bottom of the vent. The fragment is that shiny object seen at the very right of the video once the camera gets to the bottom of the vent

    Then I used the magnet attachment on the camera. Apparently it’s a neodymium magnet because it is pretty strong. 

    The magnet was able to lift about 2.5 oz of the wrench material (I tried it) and the fragment was only 0.1 oz so I had a good ratio. Yet I was concerned that the fragment may get caught in the tube offsets coming out and fall back in. So I put some tape around the magnet to prevent that. I don’t know if it helped but the piece came out. I also bent the magnet holding attachment a bit to get it to position sideways down the vent hole. See photo here.
    It helped a lot that there was not anything magnetic down the vent hole. I did a trial run before the final attempt to make sure there was nothing that would pull strongly on the magnet.

    Here is the video where the wrench fragment got picked up. Unfortunately you cannot see the fragment being picked because it is behind the magnet. But I felt it when the fragment was picked up. A little click vibration propagated up the camera cable so I knew that I had caught something. So I lifted the camera up slowly and carefully and was happy to see the fragment attached to the end.

    Thanks everyone for your help! Your suggestions were very helpful in giving me the confidence to do this.

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