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engine noise

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nascar7613

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2000 Duece, tapping noise coming from the engine. Took the lifters out, they looked and felt fine. took off the rocker covers. Found that I could move one of the rocker shafts back and forth with my fingers. Seemed to be too much side to side movement of two of the rocker arms, although they were within Harley tolerances. One of the rocker arm bushings was worn to where I could move the shaft up and down slightly. So. I replaced the rocker bases with deltron bases, put in S&S roller rockers and new rocker arm shafts, noise still there. Went ahead and replaced the lifters with feuling lifters and installed new screamin eagle adjustable pushrods. Noise still there. I'm obviously barking up the wrong tree. When riding the bike, the noise is more noticeable on decelerating. If accelerating hard, the noise is not noticeable, although the bike is fairly loud. My question is what would cause a loud noise upon deceleration and light throttle but not on hard throttle. Any thoughts would be appreciated.
 
Google this product Rocker lockers, read several of the search results and see if it may be your noise.
 
How many miles on the motor? What modifications?

Check out the Rocker Locker website. Could be your issue but if it is, there will be witness marks on the right side bolt that secures the rocker support plate to the rocker box. The website will have pictures of the witness marks. Look at your old shafts; no witness marks, Rocker Lockers won't solve the problem and we need to look elsewhere.

http://rockerlockers.com/wordpress/
 
Actually I have a set of rocker lockers, but the delkron rocker bases bolt holes are too small to install them. This is not the cause of the noise. The noise is too loud to be that. I think the key is that the noise intensifies when decelerating. It might not be in the top end, it sounds like it's coming from there, but the way the noise travels in these engine, who knows. When I put positive pressure, as in accelerating hard, the noise goes away, but negative pressure, as in decelerating, the noise intensifies, at light throttle the noise very noticeable, but not as loud as when decelerating. I haven't pulled the cam cover, but if the shoe on the tensioner has broken, would the chain noise be louder with negative pressure, I don't know.
 
Impossible to diagnose a "noise" without hearing it. Sometimes a video clip with audio will help.

Take the bike for a ride to get the motor up to operating temp, park it in the garage and get it on a lift/jack to make it easier to use the stethoscope and try to pin point the source of the noise. If the noise only presents when the motor is under load, as when riding, the noise may not present in the garage. If that is the case, that will tell a lot.

Drain some oil and check for metal or any other particulates that should not be present. There are three things to look for that would help identify an internal problem; bronze, aluminum and the delron tensioner material.

You may have to open up the motor to find and eliminate the noise and the cam chest would be a good place to start; sounds like you have eliminated the rocker arms, shafts and pushrods as a source. Have you replace the OEM chain tensioners? If not, they would be the prime suspect. If the cam chest checks out OK, next stop is the primary.

Worst case, the noise is internal; piston slap, wrist pin loose, crank thrust washers worn beyond service limits or worn rod bushings. Anyone of those will show up in your oil.

That's all I can suggest at this point. These noises are sometimes very challenging to run down. You still haven't told us how many miles are on this motor and whether or not any modifications have been made.
 
The engine supposedly has 11000 miles on it. This is a customers bike who bought it like it is now and he doesn't know what cams or displacement the engine is. The way the bike runs I would say it's a 95" with a non stock cam. It has screamin eagle heads, two Mikuni carbs. It has no compression releases and turns over easy, so I don't think it's a high compression engine, unless it has the compression release cams.
 
Pulled the cam cover, every thing behind it looked normal. Took the rocker cover off the front cylinder and ran the engine. It is getting plenty of oil up there, can't see anything unusual watching it running. Sure sounds like the noise is coming from the front cylinder. The customer stated that the noise appeared all at once and has remained ever since.
 
Run a compression test on both cylinders.Then, if you have one, use a Bore scope in each cylinder
and see what they look like.
tourbox
 
I have heard loose compensators sound like its coming from the cylinders or top end. Plug one ear with ear plug, take a steel or wooden rod to the other ear and touch it to all the cases and covers like a stethascope that may help isolate the area.
 
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