After chasing a neutral rattle on and off for the past year I discovered that a lot of it ,if not all of the rattle was coming from the OEM Tensioner. Was installing a set of Barnett discs and just for grins I shook the chain up and down and damn..there was the noise I was hearing in the primary that I thought was all coming from transmission. Fired it up with no primary cover on, stuck a screwdriver between the tensioner shoe and frame and pried up..bingo, no more noise .
Next tried tightening up the chain to about 1/4 to an 1/8" slack and it was quieter at cold idle not too bad , went for a ride, noise back after it warmed up. Then I slipped in a Hayden tensioner to test and damn...dead quiet, took a nice long ride ... no more rattle cold or hot. Then made a couple of calls to John Sachs and Ron (rabos ) on HTT.
Thanks to John Sachs and Ron ( rabos) on HTT and Harry for a little schooling and their help on what was happening. Harry had same issue on one of his builds had the same issue.
Here is Ron's reply to my message which explains it much better than I can:
From Ron On HTT
If you smack the top of the chain, I bet you hear the clunk. It's from the shoe hitting the stop. Making the chain tighter will usually bring on the clunking at hot idle because with heat the space between the shoe decreases and erratic engine idle will make it hit more frequently and takes less chain whip to do it. Smooth as possible idle is a must to get the OEM tensioner to stay quiet. A looser chain will cause more whip bottoming the shoe also if idle is rough. Very fine point where it will work quiet cold and hot.
In both cases, pulling the clutch in takes some resistance away from the drive. There is less mass in the trans area with the plates separated so the engine pulses don't whip the chain as much with this reduced load between the two points in your case. Gear set in both cases is taken out of the mix. I have tried the Baker tensioner and it will eliminate that OEM tensioner sensitivity to shoe clunking. A poor chain can also drive the OEM nuts if it has too much deviation in the loose and tight spots when checking tension.
Ron
I have no doubt that I had originally had some neutral rattle and after we installed the Baker door it was quieter but not to my liking. If I had to to do all over again and I would pull the primary cover first make sure the chain is adjusted properly. Push the chain UP in the center, you'll notice the shoe starts to compress as you are pushing it up. That's there to compensate for the chain tightning when hot .
You are looking for 5/8-3/4" total slack. Static slack 1/4-1/2. FIre up with no cover and do the screwdriver test, if it gets quiet then you know. If you happen to have a Hayden laying around or can borrow one to test all the better. Hayden has a new "black shoe" they are using on the M-8 tensioners that will retro fit. It's $22.00 and very quiet.
I will probably pull the Hayden out and try the new Twin Power tensioner. To keep it reasonably quiet John Sachs highly suggested replacing the chain as well. There are basically two brands of chains, Diamond (former OEM vendor) and Regina (current OEM vendor ).
I know this was a really long post and hope I didn't bore you all to tears but if the " Neutral Rattle is buggin the chit out of you..this may help. Let me know..Greg
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Topic: Neutral Rattle & The OEM Tensioner (Read 1901 times)