Bolt missing from Cam shaft clamp

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sticky nicky
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Bolt missing from Cam shaft clamp

Postby sticky nicky » Tue Dec 18, 2012 12:13 pm

This might be a silly question but is it normal to have a bolt missing from a Cam shaft clamp? When taking the cover off there is one missing and on looking at my spare head sitting in the garage there is one missing off that as well.

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Re: Bolt missing from Cam shaft clamp

Postby NitroDann » Tue Dec 18, 2012 12:17 pm

You mean a cam cap?

There is 5 caps per cam and each has 2 bolts.

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Re: Bolt missing from Cam shaft clamp

Postby Kobsy » Tue Dec 18, 2012 12:25 pm

Not sure what motor you are looking at...?

I remember once noticing the same thing on my friends motor until we remembered that the missing bolt is used for the rocker cover aswell, maybe this is whats going on?
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Re: Bolt missing from Cam shaft clamp

Postby Steampunk » Tue Dec 18, 2012 12:35 pm

Simple answer is no. My guess is whoever removed/replaced them last time didn't give a damn because they figured that you wouldn't find it after you've long taken possession of the car. Also, a cam bolt is not the same as cam cover bolt as the latter is not meant to be torqued up and is the easiest bolt to shear off.
Perhaps a cam bolt was used as a cam cover bolt, but that is pretty stupid to cannibalise a bolt from a part that is a lot more essential.
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Re: Bolt missing from Cam shaft clamp

Postby Kobsy » Tue Dec 18, 2012 12:49 pm

Hang on steam I think your misunderstanding what i meant. :?

On my friends motor, on the frontmost cam caps, instead of having 2 separate caps his motor had a single "double cap" which had room for a 5th bolt between where the 2 cams run. This centre bolt hole was used as a rocker cover/cam cover bolt.

And if I remember correctly, at least some motors have covers that use a torque setting. Not that many people care about it anyway.
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Re: Bolt missing from Cam shaft clamp

Postby bruce » Tue Dec 18, 2012 1:52 pm

Same story here with my old Suzuki. 3 bolts were missing, but found 1 of them sitting in a depression. I have no idea where the other 2 have gone (checked everywhere plus they're too big to fall down any holes). I'd like to take the sump off to check though (now that's too much work). Car's been running fine for 150 thousand kays.

Kobsy wrote:I remember once noticing the same thing on my friends motor until we remembered that the missing bolt is used for the rocker cover aswell, maybe this is whats going on?


I thought this might have been the case but after thinking, there are seperate holes for the cover bolts.
I wonder if they were lazy at the factory (but Suzuki quality is actually very good)?

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Re: Bolt missing from Cam shaft clamp

Postby sticky nicky » Tue Dec 18, 2012 3:09 pm

IMG_0919.JPG


Ok guys Ive attached a pic for you. Basicly, full engine rebuild done 200 kms ago, took off cam cover to replace with painted one and took pic then to show mechanic. Then replaced cover. Showed him pic today, he says it must have happened during the 200kms?? so not driving it now till we get the cover off on the weekend and see if there is a loose bolt in there which Im sure we would have noticed when we had the cover off. I have this feeling it was never put it after the rebuild :? I have a spare one I can put in.
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Re: Bolt missing from Cam shaft clamp

Postby NitroDann » Tue Dec 18, 2012 3:22 pm

Your mechanic is full of sh*t.

If it was tightened correctly it couldnt possibly come loose.

Maybe he assumed that because you are a lady and you would never look in there after he lost it?

Yes those are called cam caps BTW.
Similar ones made of iron hold the crank in and are called Main Caps.

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Re: Bolt missing from Cam shaft clamp

Postby Steampunk » Tue Dec 18, 2012 3:34 pm

sticky nicky wrote:I have this feeling it was never put it after the rebuild :? I have a spare one I can put in.

This^
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Re: Bolt missing from Cam shaft clamp

Postby manga_blue » Tue Dec 18, 2012 3:35 pm

x2 Dann.

If the bolt is missing because the thread is stripped then a machine shop should be able to do a thread repair in situ. Depending on where you are there are also mobile thread doctor vans.
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Re: Bolt missing from Cam shaft clamp

Postby project.r.racing » Tue Dec 18, 2012 4:00 pm

what all the crap inside the spark plug tubes?

also the outside cam cap bolts dont have enough space to screw out once the engine cover is on.

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Re: Bolt missing from Cam shaft clamp

Postby manga_blue » Tue Dec 18, 2012 4:15 pm

project.r.racing wrote:what all the crap inside the spark plug tubes?

also the outside cam cap bolts dont have enough space to screw out once the engine cover is on.
Yep, I reckon he stripped it and couldn't be bothered getting it fixed. So he just left it out. Slack.
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Re: Bolt missing from Cam shaft clamp

Postby sticky nicky » Tue Dec 18, 2012 6:03 pm

project.r.racing wrote:what all the crap inside the spark plug tubes?

also the outside cam cap bolts dont have enough space to screw out once the engine cover is on.


Thats an interesting point, no room for them to unscrew with the cover on, if thats the case it was was left out by the mechanic. I used a donor head which had been sitting around for a while in the rebuild as mine was stuffed. The donor head was sent away for a recon, valve stem seals etc, maybe they should have cleaned out the spark plug tubes too?

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Re: Bolt missing from Cam shaft clamp

Postby hks_kansei » Thu Dec 20, 2012 9:40 am

The stuff in the plug holes looks very similar to the dried goo when a head gasket blows ans the oil and coolant mix.

If the engine has blown a head gasket in the past it may be from that (strange that it's in the plug holes, unless the mechanic took the plugs out and cranked it to spit the liquid out)



As for the cam bolt thing, yes, there is supposed to be a bolt there, and it's best to have it there since the point of those bolts/covers is to hold the camshaft in place.

I'm not sure how much risk there is running without one, but there is a possibility of the camshaft breaking, or the cap breaking (which would then bounce around and break countless other things in the head)
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Re: Bolt missing from Cam shaft clamp

Postby bruce » Thu Dec 20, 2012 2:17 pm

Mine are tiny screws.
Did you run a magnet in all the crevices and check that it wasn't somehow stuck to the underside of the cover? For the life of me I still couldn't find my 2 missing screws.


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