686 is Knocking
#11
686 is Knocking
Originally posted by: Redblue75
so did I just ruin evrything or is there still a light at the end of the tunnel.
so did I just ruin evrything or is there still a light at the end of the tunnel.
Ward is also correct in saying that after a new cam, springs, etc, that there will be added valve train noise. I know I still worry about it from time to time and I have had my motor modified now like 2 years. It's hard to get used to. LOL
#13
686 is Knocking
If it only does it on the compression stroke it wouldn't be P-V clearance problems. Both valves are closed during the compression stroke. The intake valve chases the piston after the exhaust stroke and the piston chases the exhaust valve during the exhaust stroke, which is where most damage is done. Was the squish area checked? Was the right head gasket used? If everything there is ok, my guess would be valvetrain noise, possibly rod/wristpin. the teardown will tell.
#14
686 is Knocking
yes it does have 1 oversized valve but the guy that put it together measured to see if the releif cuts in the top of the piston were big enough before assembling. and it's a brand new wrist pin, could it have been defective from the factory. Because we put the one in that came with the piston. Just out of curiousity how much does it normally cost to have an aftermarket rod put in.
#15
686 is Knocking
Put some grease or lipstick on the valves then turn it over by hand and see if it gives the piston a kiss. This should tell you which one of your valves is being bad or if its even that at all. Price of a head gasket wont kill you but murdering your valves will. This wont tell you whether it will hit when your piston gets hot and expands but it will tell you if thats whats knocking since it does it even when you turn it over by hand.
#16
686 is Knocking
If Trinity put 1 32mm intake valve the piston does have to be relieved for that 1 valve. It needs to be relieved on the outer edge of the piston. You need .050" clearance on the intake an .070" on the exhaust. It is very easy to tell if you have the minimun clearance. Set your valves at 0 clearance. Measure the hight of the adjuster and tighten it up .050" for the intake and .070" for the exhaust. do one at a time so you can tell which one is hitting. Remove the plug and turn over by hand. If you feel any resistance stop!!!
#17
686 is Knocking
If all is true with what you say about hearing the noise at top dead center than all the valve should be closed right?
I would take the valve cover off and see if all the valves are closed at top dead center if they are not you should check you cam timing marks. Make sure it is not advanced or retarded. With that high of compression being 3 degrees off could pose a problem.
A little engine building tip for all always measure even michinest makes mistake and double check everything. A good tool for checking valve clearance is playdow, put a round ball were each relief is on the piston assemble the head, ajust valve to spec an turn motor over by hand, pull head off and measure the thickness of the playdow, if that is to spec then your good to go if not than michine the reliefs in you piston.
I would take the valve cover off and see if all the valves are closed at top dead center if they are not you should check you cam timing marks. Make sure it is not advanced or retarded. With that high of compression being 3 degrees off could pose a problem.
A little engine building tip for all always measure even michinest makes mistake and double check everything. A good tool for checking valve clearance is playdow, put a round ball were each relief is on the piston assemble the head, ajust valve to spec an turn motor over by hand, pull head off and measure the thickness of the playdow, if that is to spec then your good to go if not than michine the reliefs in you piston.
#19
686 is Knocking
Well went and checked on it today. No Knock. The problem was the decompressor or whatever it is refered to. Was installed 180 deg from where it should have been . With it like this the cam chain was not tightening either. Thanks for the suggestions. Glad was an easy fix. Just so you guys know they tore it down all the way just to check if any other problems. Now all I have to do is jet and I should be good to go. Thanks again for the Help.
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MikeyBoyesq
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08-10-2015 11:11 AM
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