sand in head


10 replies to this topic
  • falshh

Posted November 15, 2005 - 09:10 PM

#1

Ive been riding the sand track and I was checking my valve clearances and noticed right in the middle of the head, it looks like its open the the atmosphere (no oil area) where it leads to the breather hose, some sand must of worked its way through the hose, anyway this cant get into anything and so harm can it?it looks like its seperate from the engine internals ie lubrication areas

also what tire pressure and clicker setting for sand is recommended?

  • Butta

Posted November 16, 2005 - 06:13 AM

#2

Hmmm, I can't say for sure on the sand in the head being ok, as it just doesn't sound right at all. As for the tires and suspension, I used to run about 10 psi front and rear and set the suspension up as stiff as possible. The sand gives a lot and will in effect be your suspension. Might want to route the breather hose to the airbox or fit it with some sort of filter to keep sand from finding its way up to the head.

  • grayracer513

Posted November 16, 2005 - 09:54 AM

#3

It can and will get into everything from there. The oil you see in the top end runs back to the crankcase, where it's picked up by the return pump and sent to the tank. From here, the oil filter should remove it, but only after it's gone through both oil pumps. If it gets past the filter, it's big trouble.

  • falshh

Posted November 16, 2005 - 06:44 PM

#4

If you follow the large black tube (breather tube) from the left side of the bike up ,it goes into the top of the valve cover in the middle.If you pull the valve cover off you can see it goes into its own area seperate from the cams etc an area where there is no oil , not sure what that area is just wandering if it can work its way in the engine from there??right now I am almost positive its not in the oil stream anywhere.

  • NAFLASH

Posted November 16, 2005 - 08:18 PM

#5

How does sand work its way up that breather tube? Atleast on my bike the compression from the motor is constantly pushing air out of the breather and i cant see anything working its way up that long tube and not getting blown out some how. unless you have really low compression, i cant see anything getting up that tube. If your having problems with sand getting in there go to pep boys and buy a little K&N breather filter, ive seen them on Civic's and its probably the same size hose. correct me if im wrong.

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  • Fastest1

Posted November 16, 2005 - 08:43 PM

#6

Actually the air in the breather tube is going both ways rapidly in pulses. The piston is still going up and down in a sealed cylinder so air is being moved on the back side of the piston also.

  • grayracer513

Posted November 17, 2005 - 09:02 AM

#7

If you follow the large black tube (breather tube) from the left side of the bike up ,it goes into the top of the valve cover in the middle.If you pull the valve cover off you can see it goes into its own area seperate from the cams etc an area where there is no oil , not sure what that area is just wandering if it can work its way in the engine from there??right now I am almost positive its not in the oil stream anywhere.

The area you see in the top of the cam box is a baffle to help separate oil from the air that moves in and out through it. I assure you that if you remove the crankcase drain and pour oil in through the hose fitting on the cam cover, it will run right out the bottom.

But, to have gotten sand in through that point, it would have had to be extremely fine sand, and the end of the hose would need to be stuffed into a dune while the engine was being started. Air does move in and out of the breather, but more air passes through the hose at cranking speeds than at higher rpm. Even at an idle, the engine is turning around 2000 rpm, which means the pressure is reversed 67 times a second. That doesn't allow enough time for a large volume of air to be forced through the hose in either direction before being told to go the other way. And, while under power, at least a small amount of combustion gas gets past the rings and into the crankcase, creating a net outward flow of air. I think that if you pull the hose off and swab out the top end of it, you'll find little if any grit there. Your sand was probably introduced through an oil filler.

  • falshh

Posted November 17, 2005 - 06:14 PM

#8

well thanks for the imput I was at a sand track while it was raining and I think sand got in the breather hose from going through puddles all day, the hose was coated the whole way up with sand and there was only about 20 grains of sand in the head, not much but enough to be concerned,I dont think sand was sucked up there, and the tube never saw any sand directly and I never tried to start it in a puddle or loose sand near the breather.I saw a couple of threads where guys route the hose to the air box I just want to find a good fitting that will connect it to the box that doesnt look hokey.Maybe a small bulkhead fitting and a 1/2pipe x1/2barb fitting?

  • Vibeguy

Posted November 18, 2005 - 01:47 PM

#9

Also check to make sure your decomp plug is still in place. I have seen missing decomp plugs lead to dirt/sand in the head as wel/ as a big oil mess on the front of your engine.

  • grayracer513

Posted November 18, 2005 - 03:08 PM

#10

Good point, Vibeguy.

On the fitting to the air box, I know one guy who went to the auto parts store and looked through the selection of little filters used in automotive PCV systems. He found one with the right sized hose, cut a hole in his air boot, and glued it in place from the inside. Then he attached the hose to that. You can hardly tell it's there.

  • Shawn_Mc

Posted November 18, 2005 - 03:15 PM

#11

K&N makes a little filter you can put on the breather hose too.

Anything would have to better than having it wide open.





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