What's the proper way to remove and install valve guides?
Posted 08 March 2005 - 06:08 AM
Posted 08 March 2005 - 07:05 AM
Posted 08 March 2005 - 09:06 AM
Posted 08 March 2005 - 02:03 PM
Posted 08 March 2005 - 02:13 PM
new guides chilled should slip right in.should.soemtimes its a big pain.
its extremely easy to ruin a head.
if i had a crf head that needed guides i would buy a new head.honda heads are pretty cheap.
Posted 08 March 2005 - 03:20 PM
I figured that was the procedure because i called RHC one day and he was in the middle of it.... said he had some hot heads.... put the phone down and I think I heard him banging them out.
Posted 08 March 2005 - 03:30 PM
what proceedure do you high tech guys do to remove and install valve guides? i have -80 degree freezers here at work i could throw the guides in. i figure with a little heat on the head and they would go in fairly easy. is this a correct assumption? how do you properly remove them? i won't hammer them out. please enlighten me on the proper methods. or, should i have the dude that is going to cut my seats install them? that's my last resort as i am broke/cheap and do everything myself that i can w/o risking the hp or reliability. thanks.
Heating the head and using a soft metal pilot/punch like bronze is the proper removal method. It's important to keep the overall head temp below about 275 degrees F or you risk having the valve seats fall out (usually in the 350F + range) . Reheating the head and freezing the guides along with an anti-gall lubricant the proper method for reinstall. It's important to keep in mind that the CRF doesn't have a positive stop like most valve guides, so you have to make up a fixture with a dial indicator to ensure that the guide is sunk to the proper depth.
The good news is the guides rarely wear out in the CRFs so it's unlikely that you'll have to change them any time soon.