cylinder head bolt loose

Hi

The weather here in Sweden i great, and I've already been out som times with the bike. This is how it looks now.

My problem right now is that a little oil is coming out from 1 of the 8 cylinder head bolts (not the valve cover), more specifically one of the outer ones on the right hand side. As it is, the oil sipping out is drawn backwards by the wind and gets on the cylinder and carburettor.

Any danger with oil sipping out here?
Indicates something specific?
Just a matter of tighten it a bit?
Or is it a washer that should be changed?
Any danger loosen the bolt to change a possible washer?
Anyone knows the forced to be used when tightning?

Happy touring withyour bikes

/Martin

Hello Martin:

Always try the easy fix first...assume that the head bolts have loosened up and need to be retorqued...check the manual for the torque pattern and the torque stats. Buy or borrow an appropriate torque wrench If that doesn't stop the oil from oozing, then other measures may be necessary.

I'll look at a 650 manual this evening and post the torque pattern.

The head bolt torque specs for my 750 are about 27 - 33 foot-pounds.

Uncertain whether applicable to KZ650, but large fours use a copper washer under each outside head nut which serves as a gasket to seal against oil leak. Four copper washers, being two on each side under the outside head nuts. Washers under the other head nuts are steel (where there's no oil channel involved).

Thinking maybe a steel washer was improperly fitted instead of a copper washer at the site where leaking.

Just a guess.

Good Luck!

Patton's right on the 900-1000, but 650 doesn't use copper washers. Just plain old washers. I've never heard of this particular leak. Add it to the other 122 KZ650 leak spots. I don't see oil being near the studs on a KZ650 for any reason.

Yeah, the 650s have the oil for the had come up through a separate oil galley located between the outer studs on each side - there are two restrictors w/o-rings in each galley, one at the cylinder base and one between the cylinder block and the head. Even if one of the top o-rings is broken your head gasket would prevent the oil from reaching the studs, unless both the o-ring and the gasket is broken which is unlikely.

Martin, you mention 'one of the 8 cylinder head bolts' - if you are referring to the head nuts you have 12 of those, I would like to see a pic of the bolt/nut you are talking about.

Here's a pic of the oil galley top restrictor/o-ring:

And the one at the cylinder base:

Thanks everyone for your information.

After a long day riding the bike the side of the bike had leaked more oil. I now noticed, however, that it didn't came from the head bolt but from one of the valve cover bolts, that actually was loose.

My apologies for misleading you all. But I learnt some new things though..., which is always nice.

I have now tightening it, so next ride will tell. I hope the cover haven't been bad by having one of one the bolts loose when it was warm. My torque tool is only for bigger torques, so i couldnt use it on this bolt. Tried to not tighten it to much though.


/Martin