I just built a new/used twin cam motor using S&S cases and eBay take off harley parts. On startup the bike runs fine. But, the lifters seem to tap, and after about 3-4 minutes of running it pukes oil thru the air cleaner. At this point I get nervous and shut it down.

How long should it take for the hydraulic lifters to fill with oil and be quieter? Why am I puking oil thru the breather/air cleaner? Could it be a problem with oil not draining from the top end to the bottom? Is it a major oil pump problem? Am I missing something simple or obvious?

Any help would be greatly appreciated. I can't ride my new home-built bike until I figure this out

 

Hi I was thinking about your problem and not knowing more about what aftermarket parts you used here are some general ideas. First your ticking. Lifters pump up Quickly did you soak them in oil before install? are you running stock pushrod or adjustable? Thay should be adjustable and are thay adjusted correctly? And with the oil pucking. Well You seem to have oil giong to the top for it to puck witch helps with the first part of ticking noise your lifters are getting oil. the top end oils throught the pushrods on twincams and the heads have breather valves that lead to your tubes on the air cleaner so I think eather your beathers have a problem or your not draining out of the head. also double check your rocker housing gasket will go on two ways and only one is correct. the beather channel should be covered. check this first.
good luck and go out and have fun
Ed

 

Before I go into a l ong post More info is needed.

1. Stock pump??
2.S&S read breather?
3.WHos rocker boxes??
4.Lifter info, cam, pushrod?
5.Metal or plastic breathers?
Thanks

 

Im using a stock oil pump, an S&S reed valve assembly, S&S gear drive cams(very mild), plastic breathers, stock harley rockers. I didn't know about soaking the lifters in oil before use. I'm running stock non-adjustable pushrods and I did check them for proper fit, they seem fine.

Thanks for the help guys.

Here is what Im thinking of trying: Pull the cam chest apart and double check the oil pump install (possible that the thin & thick rotors are switched?). Double check the reed valve install. Pull the rockers and check the gaskets for proper install (hole blockage).

If I have to I'll pull the whole top end and check to see if it has proper oil drain passages, although everything looked fine going together.

Is it possible there is a problem with the breather assemblys? Is there a difference between the plastic and the metal ones. I used the plastic as I thought they were an upgrade and lighter weight.

Again, thanks for the help.

 

I have no faith in the reed valve setep this is bar far the not the first time I have encouted this. The valve is designed to help but I have found that they end up casuing huge sumping problems. Then they puke the chest cavity full and the end result is the mess you have. I do not use one and have removed several after installing them per the customers request, I have spoke with S&S ans they swear that it is not there reed valve. I remove it the puking is gone and ther engine has more power as the oil can escape from the crank case. I can see how it should work but in the case's where i have used them they are removed due to problems . Heck they are even a lousy paper weight. .

I am not saying that you should remove it but after you run down normal issues and that is all there is left well it is what it is. You could hav eteh pump together incorrectly but most times it will not make oil pressure. One more thing toss the plastic breather they are prone to warpage and are going to cause you head aches in the future. HD started with metal then went to plastic and now back to metal due to the problems with leakage. Keep us posted with what you find. I can get you a exploded view of the pump if you need it, as well as info on algining of the pump. Just let me know