Jackhammering sound coming from Cylinder Head

houseowax · Post by **houseowax** » Tue Jul 20, 2010 9:09 pm

I've been poking around with this bike for months now and I'm finally getting to understand it. Still, it seems determined to keep me guessing at every turn.
I've finally got it starting reliably (kickstart only; we'll get into the electrical problems later) but when it starts up cold the left side of the cylinder head -specifically the point between the two halves of the head- emits a small amount of white smoke and it makes a terriible clattering 'jackhammering' sound.
Also of note and probably related is a small amount of oil that trickles out from beneath the fin and onto the header causing more smoke.
In addition, the left side header gets remarkably hot after a very short time. I've made sure the muffler and header aren't obstructed and they appear to be clear.
Lastly, I have no idea what sort of oil is in the bike- it's clean but it what was in the bike when I got it.

....OK...wait. As I read this a simple solution is occurring to me. Could it be that the two halves of the head just aren't bolted together tightly enough?

Check out the video here and let me know what you make of it.

http://www.youtube.com/watch?v=iqvKCQIH2sM

rrietman · Post by **rrietman** » Tue Jul 20, 2010 11:31 pm

blown head gasket. DON'T RUN IT ANY LONGER.
Good luck
Randy

e3steve · Post by **e3steve** » Wed Jul 21, 2010 2:43 am

I'm in full agreement with Randy; in fact, don't run it until you've dropped the motor, lifted the head and examined pistons/valves/mating surfaces for signs of impact.

houseowax · Post by **houseowax** » Wed Jul 21, 2010 9:05 am

Thanks for the tip, fellas- I guess my wishful thinking didn't pay off then. I envisioned torquing down the cyl head and being done with it.
Oh well- In a way this is OK with me; I'm looking forward to dropping the engine and having a look inside.

Does anyone have any last minute advice for me regarding replacing the head gasket? I understand that Honda OEM is the way to go and I've read enough about Hondabond to know that it should be applied VERY sparingly so as not to squeeze into the cylinders or clog the breathers.

Thanks in advance for any advice. I'm going out of town for a few days and will probably spend my vacation wishing I was home and up to my elbows in greasy engine parts.

teazer · Post by **teazer** » Wed Jul 21, 2010 9:08 pm

NO Honda bond, 3 bond, Yamabond or any other gasket goo is required on a head gasket - or any other gasket if it comes to that.

The surfaces have to be flat with no big dips and gouges of course.

rrietman · Post by **rrietman** » Wed Jul 21, 2010 9:53 pm

An old mechanic tip that works very well on our Honda motors. soak the gaskets (any gasket) in motor oil (any oil) for a few hours before install.
Randy

houseowax · Post by **houseowax** » Thu Jul 22, 2010 6:40 am

Thanks again and keep those tips coming!
I have a pair of head gaskets at home that have both seen some use but both seem serviceable to my admittedly untrained eye. I'll post pics of them when I return and see what you all think. I have a parts bike that I'm planning to drop and rebuild the engine on as a hands-on learn-as-you-go opportunity. I suppose the prudent thing to do would be to do this one first and use the old gaskets (if they're usable) THEN get to mine using OEM gaskets etc. Shortens my riding season considerably but I guess thems the breaks!

As always, I appreciate everyone sharing their experience and wisdom- makes the process much easier and less intimidating knowing you're all out there.