|Posted on Tuesday, January 06, 2015 - 11:45 pm: ||
Here's the background, 08 XB12XT, complete engine tear down and reassembly. Had trouble getting the heads to sit right but finally got them on and torqued. Bike is back together and put over 1K miles on and now the front cyl. is leaking from the top of the pushrod cover. Upon closer exam I see why I couldn't get the heads on right, my ham handed handling of the heads displaced the o-rings leaving a poor seal. Even though only the front is leaking so far, I can see part of an o-ring sticking out of the rear, too.
Now the question, is it possible to just pull the heads off, which could probably be done with an engine rotation, or is this just asking for the base gasket to start leaking? If I have to pull the jugs too then that probably means engine out of frame. Either way it's not a pretty picture. Any other suggestions?
|Posted on Wednesday, January 07, 2015 - 09:13 am: ||
Oh, don't worry. I was as delicate as a surgeon and as careful as is humanly possible putting my heads back on, and the exact same thing happened to me.
Do what I will do (as soon as I get through other house projects)... pop off the rocker boxes, and plug that leak from the inside with a bead of RTV, which is what more experienced builders do every time anyway. Those stupid o-rings often fail to seal no matter how careful you are.
I do not believe it is necessary to remove the head. So you aren't paying for new head and base gaskets.
|Posted on Tuesday, April 14, 2015 - 09:13 pm: ||
Dear god no. Do not try to put rtv inside the rockerboxes. If it is leaking, suck it up and remove the top end and replace head, base and Orings. lube them with oil and have a second person assist with gently seating the pushrod tubes into the orings. Globs of rtv floating around inside your motor where they could plug oil passages is no bueno.
|Posted on Wednesday, April 15, 2015 - 08:09 am: ||
I've pulled apart a KLR-250 motor that a previous owner suffocated with RTV, so I agree with your concern. But I think this is a case where careful cleaning and prep followed by a bead of RTV pressed into that gap from inside the rocker box is the right solution to the problem.
(And it was also suggested to me by individuals with some pretty extensive engine building experience.)
I believe Harley already uses RTV direct from the factory to seal the case halves on assembly also.
Always a good reminder not to just slather RTV inside a motor though, and make sure surfaces are clean.
|Posted on Sunday, April 19, 2015 - 05:22 pm: ||
And let it cure before exposing it to hot oil.