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I broke a bolt while reinstalling the oil filter cover. Can I get some help understanding where I might have gone wrong? One bolt broke, its in the picture, I managed to get it out in one piece (small miracle) and it broke in my hand shortly after I took this picture. I checked the other bolts and two more had slightly deformed.

photo.JPG

I'm admittedly new to this, and I want to continue doing my own maintenance, but I'd like some of you that are more experienced to comment on why this happened, and how I can fix it. Here's a breakdown of my process:

1. I read, I read a lot before trying this, knowing that I don't have massive experience to fall back on. I read the service manual, and the DIY oil change thing here.

2. I made sure I had all the right tools, which includes a new torque wrench purchased today. This one (or possibly this one). It's not a high-end one, but I figured it was good enough, and better than me guessing by feel at the torques. The range is 5-80 ft-lb, with a stated accuracy of +-4% (I didn't check if that accuracy applies over the full scale).

3. I set the wrench to 9 lbs. The newest service manual doesn't seem to specify a torque, but the DIY oil change guide does, as do several other internet sources. It seems that this value may have been in older versions of the manual. When I tightened the bolts, I realized this was tighter than I would have tightened them on my own. I moved to a random bolt in my shop (that I wasn't worried about over tightening) and made sure the torque wrench was working, and that I knew how to use it. 9lbs seemed tight, but not bolt-breaking tight, so I decided it was probably right. I set the wrench to 5lbs (its lowest setting). That still seemed plenty tight to me, so I decided I'd start there and then move on.

4. With the wrench at 5 lbs, I tightened the bolts. I choked up about half way on the 14" handle, and went really slow. It felt like I was over doing it, I probably should have stopped at this point. Did all 4 bolts relatively evenly. Got one all the way torqued (to 5lb). While doing the final torque on another, I felt the bolt give. I slowly backed it out and got what's in the picture. I took each bolt out to inspect. One was fine, two were slightly disformed (stretched, at the same point as the break in this one), and the last broke in my hand when I picked it up from this picture. I'm lucky it's not broken off inside.

I'm going to see about getting 4 new bolts tomorrow. I'm hoping my dealer will have these on hand, but if not- does anybody have a source to order online? I'm taking my torque wrench to work and hoping I can check it against a higher-quality one. My plan is to do like the service manual says and only tighten them by hand to about what feels right to me. Am I on the right track here? Anything else I should be thinking about?

I found a couple posts in the archives, looks like I'm not the first to make this mistake:
Warning about oil change! [Archive] - Honda CBR250R Forum : Honda CBR 250 Forums
Oil Change from Hell! [Archive] - Honda CBR250R Forum : Honda CBR 250 Forums

But it really is discouraging to have this happen on my first attempt at doing my own service. I'll be doing the minivan-drive-to-work-of-shame tomorrow.
 

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That 3/8" drive torque wrench you linked to, is too big to be accurate at the lower end of it's torque range. These oil filter cover screws (they are really too small to properly be considered "bolts") are better tightened by "feel" using either a box end wrench, or with a 1/4" drive ratchet handle and socket. There are some very accurate 1/4" drive torque wrenches available, but they are not cheap. Snap On has them, which are priced at over $300.
 

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That 3/8" drive torque wrench you linked to, is too big to be accurate at the lower end of it's torque range. These oil filter cover screws (they are really too small to properly be considered "bolts") are better tightened by "feel" using either a box end wrench, or with a 1/4" drive ratchet handle and socket. There are some very accurate 1/4" drive torque wrenches available, but they are not cheap. Snap On has them, which are priced at over $300.

It's between 7 in-lbs to 13 in-lbsfor an M8 bolt thread thread class 2 (CRS 10** series). For ft-lbs = ~.6ft-lbs to ~1.1ft-lbs. The variation depends on thread length engagement. For 300 series stainless would be double. Most people i know including my self easily do 50in-lbs by feel; definite bolt breaker there lol.

Torque = Friction*Force*YieldStrength

(update)
guess i was trying to say is stay away from the torque wrench. Rare you can get your hands on a in-lbs wrench without spending a few dollars like mike pointed out or knowing someone who has one.
 

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Hello robm, and welcome to the forum. Every once in awhile we see a post here where someone has accidentally broken the oil filter cover bolts. So take heart, it's not just you. :)

I will say that each time this happens, it seems like there is usually a torque wrench involved. Even though there is a torque value for these bolts, they are just to small to safely tighten with a 14" torque wrench.

I personally use a 1/4" ratchet to tighten the cover bolts, and am careful not to over tighten them. They just need to be tight enough to seal the gasket and to not loosen from vibration.
 

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just in general....
1. ..Almost all torque wrenches are not reliable at the lower and upper 20% of the scale. Use one with your target closer to midrange.
2... Dont choke up on a torque wrench. They are designed to work by applying the force near the middle of the handle grip.
3... Careful not to get the nm and ftlb scales mixed up.
4.... For the inch-lb scale, its a simple 1 ftlb=12 inlb, just like on a ruler.
Almost forgot.... When you put a click type away, turn it back to the lowest setting for storage.
 

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5 road hondas, no torque wrench,
changed tires, sprockets, oil etc,
all by hand, nothing ever came
loose or out..

honda engineers design and test these
fasteners, priorities including not, stripping
out engine casing threads, plus general
security of the fasteners..

everything has its breaking point..

a human foream for eg can withstand
amazing forces without breaking,
yet it can be broken using pivot points
and enough pressure, by a normal person..
these fasteners are designed within certain
failure limits.. they are just ordinary metal,
and can and will break at their breaking point..

which is beyond the also designed-in functions
of securing the oil cover to its engine casing..

if you take the fasteners to their natural stop
then into the washers limited compression,
their combined pressure on the cover will
prevent the fasteners from coming out..

think of carefully seating them in
rather than 'forcing' them down..
any, idea of forcing will result in
extra tension [in your body]
which will create extra force..

as experienced members have advised,
these fasteners are at the low end of
an average torque wrench potential..
so the danger, is in over rather than
under tightening these fasteners..

one hint perhaps, try taking the spanner
off the head when it seems fully in there,
then start again, thinking of testing for
any - small - movement, rather than
thinking of forcing it around..
 

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Get a palm ratchet. (Snap-On part number: PALMRAT) Use it for oil filter cover bolts and fairing bolts or anything else low torque. That's all you need. I love mine.
 

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I just tightened the oil cover bolts by hand, then used a spanner and turned it a little more. Still working fine, no oil leaks. I've never even picked up a torque wrench. One day I will own one.

Sent from Motorcycle.com Free App
 

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I spent my youth snapping off bolts...it became a family joke, but also a source of frustration for me. I always felt the need to be "sure" that a fastener was as tight as possible...of course, this obsession led to the aforementioned breakages.

While still in the bolt-breaking phase of my life (and shortly after I had stripped out the adjustment bolt while replacing my truck's power steering belt), an old farmer (no doubt a former bolt-breaker) gave me this simple advice which I have never forgotten: "If you find that a bolt is loose or a drain plug leaks oil, you can always tighten it some more, but you can't tighten it any more if you've already broken it."

I changed my CBR's oil last weekend and, although I received that advice more than a quarter of a century ago, I remembered it as if it were fresh, new advice.

That said, the CBR oil filter cover bolts are, indeed, small and vulnerable, and any of us could turn the wrench just a bit too much one day...
 

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I looked for the specific torque value for the oil filter cover, couldn't find it so I tightened criscross pattern by feel.
 

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I looked for the specific torque value for the oil filter cover, couldn't find it so I tightened criscross pattern by feel.
That's the best way to do it... after all four screws are finger tight, another 1/8 to 1/4 turn is all it takes to properly tighten them.

Honda lists the torque value for these cover screws in the maintenance section of the U.S. version of the Owner's Manual, not sure if it's listed in other versions of the O/M.
It seems to me that if Honda had not called out the torque value in the O/M, there would be fewer instances of people breaking these screws, as they wouldn't likely be inclined to use a 3/8" drive torque wrench on them. As I mentioned previously, the only practical way to proper torque a 6mm fastener at such a low value would be by using an accurate 1/4" drive torque wrench that is calibrated in inch pounds, which few people own.

FWIW, in the maintenance section of the Service Manual Honda doesn't call out the torque value for these filter cover screws.
 

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As I mentioned previously, the only practical way to proper torque a 6mm fastener at such a low value would be by using an accurate 1/4" drive torque wrench that is calibrated in inch pounds, which few people own.
And some of us, who do own a 1/4" drive torque wrench calibrated in inch-pounds, just use a box wrench to snug down the bolts.
 

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just use a box wrench to snug down the bolts.
Exactly what I did. Finger tight, then a quarter turn with the spanner. No leaks, no broken bolts. :)
 

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In addition to the issue of over tightening fasteners...

Since the oil filter cover screws are among those fasteners on a motorcycle which are frequently removed, I highly recommend using a light coat of anti-sieze lubricant on the threads. This will prevent corrosion and galling, conditions which cause threads to weaken and can eventually result in stripped out threads.
 

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I've found that a nut driver is by far the best tool to use for tightening these bolts. Either a one-piece unit or the appropriate socket attached to the screwdriver handle in your socket set.
It gives you a much better "feel" of exactly when the nut starts to snug up to the cover.
Since you're using wrist torque instead of arm leverage as you would with a wrench, it's also much less likely you'll over-tighten the bolt without adequate warning.
Has anyone found stainless steel replacements for the oil filter cover bolts anywhere?
Whatever the stock ones are made of it's pure crap.
The cheapest Ikea furniture comes with better hardware that that.
 

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I've found that a nut driver is by far the best tool to use for tightening these bolts. Either a one-piece unit or the appropriate socket attached to the screwdriver handle in your socket set.
It gives you a much better "feel" of exactly when the nut starts to snug up to the cover.
Since you're using wrist torque instead of arm leverage as you would with a wrench, it's also much less likely you'll over-tighten the bolt without adequate warning.
Has anyone found stainless steel replacements for the oil filter cover bolts anywhere?
Whatever the stock ones are made of it's pure crap.
The cheapest Ikea furniture comes with better hardware that that.
You can get them from Fastenal... however changing to a stainless steel version isn't going to prevent someone from over tightening them and pulling the threads out. I've had no problems with the OEM bolts that Honda uses.
 

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I've found that a nut driver is by far the best tool to use for tightening these bolts. Either a one-piece unit or the appropriate socket attached to the screwdriver handle in your socket set.
It gives you a much better "feel" of exactly when the nut starts to snug up to the cover.
Since you're using wrist torque instead of arm leverage as you would with a wrench, it's also much less likely you'll over-tighten the bolt without adequate warning.
Has anyone found stainless steel replacements for the oil filter cover bolts anywhere?
Whatever the stock ones are made of it's pure crap.
The cheapest Ikea furniture comes with better hardware that that.
Its a poor carpenter that blames his hammer.
 

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multiple fasteners combine holding power..
basic spanner [even] will multiply pivotal force..
take them in one at a time by hand, then
repeat just til they stop, continuing with next
one across from last until all come to a stop..

then, 'test' them for a little more movement
again to stop.. when all are then in to stop
they and the cover have been secured..

if anal; blow into holes, wipe fastener threads,
check mating surfaces against each other for
even matching contacts, similarly gasket..
wet thread with saliva [or high tech wet]
start by turning counter clockwise until thread
'drops in' then start turning clockwise by hand..

when all come to stop, use correct spanner
alternately across from last one to next 'stop'
without, force.. as members advise, use wrist
instead of arm/shoulder power..

these are only small ordinary metal things
under high stress loads being used as designed
for securing this cover.. a tiny amount of
stretch will happen with normal force..
this is enough for them all to act
together to hold each other in
and the cover as designed..

[if wiping them gets a snag on the cloth
run a clean nut up and down them
a few times until it runs freely]
 

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And it is not just our Hondas that suffer.

I was reading on a BMW airhead website of a fellow having trouble with one of his oil filter cover screws.

He finally asked about torque values in general, and someone pointed him to this page:
Torque wrench values and settings for BMW airhead motorcycles

From which I quote:

Oil filter outer cover plate: no matter if thermostat or GS or plain: not over 7.5 foot-pounds. I always do these by FEEL, not a torque wrench.
Tighten them in stages, evenly, back and forth. NO NEED to have them too tight!

I should add, these are 8mm steel screws going into an aluminum block.
Wrenching on an airhead takes a delicate touch in general, thanks to this combination of metals. It is not much different with the CBR250R. Although I do think the screws on the Honda are inferior to those found on the airhead period BMW. It's probably a good thing to almost destroy the fastener rather than strip out the case threads.
 

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*Please don't let this become an oil debate, but here is my guide.


Rocket Science-

Buy Genuine Honda Kit ~ $40 from your friendly Honda dealer.


Warm engine to operating temp, so go for a long blast.
Break out that foreign and rarely used object called 'Owners manual ' Page 55.

Remove rhs Fairing & rhs undercowl using 5mm allen key and phillips screwdriver. Page 50/51


Place drain pan under drain bolt,
Remove oil fill cap, drain bolt & sealing washer to drain the oil.
Remove the oil filter cover,spring, oil filter, & gasket.using 8mm socket on the 4 filter cover bolts.


Install new oil filter with 'Outside' facing out.
Install spring into filter cover, then install the new gasket & filter cover & 4 bolts carefully.
Push inwards and line it all up then tighten the cover bolts using 8mm socket on screw handle.
DO NOT use torque wrench like the manual says or you will strip the bolts,
12Nm is about a billion times too much.


Replace sealing washer and oil drain bolt, torque to 24Nm.
Put 1.5l 10w-30 oil in filler with small clean funnel then replace filler cap.
Start engine for one minute.
stop engine & wait 2-3 mins then re-check oil with bike level.
Check for leaks.
Reinstall fairing & undercowl.

:)







*Do not work on a motorcycles without using the correct tools for the job, and mechanical sympathy.
 
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