Question about 2004 Harley Davidson Softail Heritage Softail Classic

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1996 harley softail classic

Hello my brothers, my primary is leaking from in between it and the crankcase, also my oil tank keeps filling up. is there a seal in between the primary and the crankcase that may have gone bad or is it something worse? the bike has 135,000 miles on it. thanks, keith

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The primary case o ring needs replacing and the cause of you oil tank filling is a pos pressure from the primary causing back pressure in the main oil pressure this needs to be fixed ASAP because this will be starving your engine of oil under running condition

Posted on May 15, 2014

Testimonial: "Thanks for the response Chris. I found my repair manual and can see what your talking about. Not the way I planned on spending my saturday. Thanks again."

  • Chris Southgate May 16, 2014

    Any time just keep on ridding

  • Mike Steele
    Mike Steele Sep 04, 2016

    how do you access the o ring?


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There's an o-ring between the inner primary and the crankcase, probably bad.

Posted on May 14, 2014

Testimonial: "Would that cause the primary oil to leak into my crankcase and fill up my oil tank."

  • keith j kemper
    keith j kemper May 15, 2014

    Thanks for the response Strech

  • Dwayne Eversole Jul 13, 2017

    Guys I have a 96 fatboy just took the primary case off the lip on the motor where the ring is is cracked a little should I be sweatin??


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Hey guys I have a 96 fatboy softail I took my primary off today because some of the inner primary bolts were loose but after I took it all off right on the lip of the motor where the o ring goes is cracked about half way around should I panic!!!!

Posted on Jul 13, 2017

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I would go ahead and replace the shifter seal,and the main transmission shaft seal while your there. Good chance that both of them are leaking as well.......

Posted on May 17, 2014

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Posted on Jan 02, 2017

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1 Answer

How to replace drive belt on a 1993 harley davidson heritage softail classic?

To remove a Softail drive belt FIRST remove the rear wheel then remove the primary chain, the clutch, the engine compensating sprocket, and the chain adjuster as an assembly, then remove the primary chaincase housing, place a support under the rear fork and engine, remove the pivot shaft and spacer, slip the drive belt off from the transmission sprocket.

To replace a Softail drive belt FIRST not that all belts, used or new, must never be formed into a loop smaller than 5.0 in. (130 mm), and must never be bent backwards because this can severely weaken the belt and cause premature failure if it, then install the belt over the transmission sprocket, install the pivot shaft and spacer, remove the support holding the engine and rear fork, install the primary chaincase housing, the primary chain, the clutch, the engine compensating sprocket, and the chain adjuster and the primary chaincase cover, fill primary the primary chaincase with oil, install the rear wheel, align the rear wheel and properly adjust the belt tension to the specified deflection.

Apr 28, 2014 | 2000 Harley Davidson FLSTC Heritage...

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What is the recomended oil for a 1997 harley davidson heritage softail classic

Harley recommends you use their 20w50 or Syn 3 (synthetic) oil. If you use Syn 3, you can also use it in the trans and primary. If you use conventional oil, Harley's Formula Plus goes in the trans and primary. Truth be told, any good high quality motorcycle oil (Amsoil, etc) made for air cooled engines will work in the crankcase.

Jan 29, 2013 | Harley Davidson FLSTC Heritage Classic...

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How to take a starter off a 1995 Harley Davidson heritage softail

Remove the primary cover. Remove the small bolt at the end of the starter. From the right side of the bike, remove the two bolts holding the starter to the back side of the primary housing. This job is much easier if you remove the oil tank to get at the starter bolts, but I have done it with the oil tank in place, by using long ball allen wrenches. Always replace the locking tabs at the end of the starter when replacing the starter, or removing it from the bike for any reason,

Aug 11, 2012 | 2000 Harley Davidson FLSTC Heritage...

1 Answer

Oil leaking from oil tank into primary on a 1976 flh 1200 hd

The oil is most likely seeping into the engine and then into primary on your bike. This commonly know in this area as "oil sumping". It's quite common on the old Shovelheads and on Softails. The reason is that the oil tank is higher in the frame than the engine and gravity does it's thing over time. If the bike is allowed to sit up for an extended period of time, the oil will seep past the check ball in the oil pump and fill the crankcase with oil. Once the crankcase gets filled, the oil seeps into the primary through the Timken bearings on the left side of the engine.

If the primary is still in it's stock configuration, simply put a deep pan under the bike and start it up. It will pump a lot of oil out of the crankcase vent hose underneath the engine but it will eventually stop. Unless the primary has been converted to a "closed wet system" like an Evo has, the engine will pump the oil out of the primary as well. After a few minutes of running, shut the engine down and check the oil level. You can leave the oil dipstick out and watch to make sure oil is being pumped back into the tank. When it seems like all the oil has quit "puking" out of the engine, make sure the oil level is at least to the lower mark on the dipstick. Like I said, if the bike has been sitting up for a while, this is quite common.

Now, if he bike has been running and all the oil is being pumped into the engine but isn't being pumped back out, you may have a scavenge gear key sheared. This is unusual on a Shovelhead because they had metal breather gears in them. The Evo engines, on the other hand have plastic breather gears in them and they will break a tooth off the plastic gear, it'll go into the oil pump scavenge gears, shear a key, and the oil pump will quit pumping oil. If this is the case, you will not see any oil being pumped back into the oil tank. You can tell when it's being pumped back because the oil in the tank will be moving and it will be kinda foamy on top. This is because the oil is being pumped back to the tank. If the pump is not pumping the oil back to the tank, you must disassemble the oil pump or the cam chest and replace the sheared key.

Good Luck

Apr 30, 2011 | Harley Davidson FLHT Electra Glide...

1 Answer

2001 Heritage softail, carburated. Gas in oil.

If you had gasoline in your oil, there's only two ways for it to get there. It either came through the carb or someone poured it in there.

I've been messing with Harley's since 1966, back before they created these cute little names for the engines like Panheads, Shovelheads, Evolution, Blockhead, Fathead. We only had two engines, Sportster 61 cu. in, and the 74 cu. in. in the big bikes.

Now, the way the fuel got into your gasoline was through the carb. If you've ever watched an old timer get off his bike, he'll reach under the tank and turn the fuel off. This was keep what happened to you from happening. It worked every time. The problem these days is in their infinite wisdom, Harley has adopted the misguided conception that the Japs started, the vacuum operated petcock. The absolute worst invention man has ever designed and put on a motor vehicle.

Now, in both the petcock and the float bowl of the carb you have a "needle and seat" all it takes is one very small bit of trash to cause the gasoline to seep past the needle. Keep in mind now that gasoline has a lower viscositiy than water. It will go where water won't go. It's thinner. A lot of gasoline can seep past a needle and seat in a 12 hour period. I've seen fuel tanks empty themselves in that time.

I've fixed many bikes that had the vacuum operated petcocks on them. They started putting them on the bike in 1996. I've seen people stranded beside the road with full tanks of fuel but not a drop getting to the carb. I've seen gasoline pouring out the small vacuum line (probably what happened to you) after the engine had been flooded out due to a ruptured diaphragm. And, I've even seen a couple of cases where the engine was sucking air through the petcock and would not idle or even run very well.

Now, when you change the oil on a harley engine, you don't get all the oil out of it like you do on car engine or a Japper engine. There will be a certain amount of oil left in the top of the heads and the camchest. Also, the gasoline fills up the crankcases that are supposed to be empty of oil. If you have a quart of gasoline that has run down past the rings into the crankcase, you now have one extra quart of fluid in your oil system. Whenever I suspect something like what happened to you, I always take the spark plugs out and spin the engine over a few times to get any excess fluid out of the crankcase. It will blow it out of the crankcase vents which in your case is in the heads. Those big bolts that hold the air filter backing plate on are hollow and are actually crankcase vents.

So, in short, my suggestion is to take that vacuum operated petcock off your bike, plug up the vacuum hose, and purchase a high quality manually operated petcock like a Pingle. They're expensive but if you get into the habit of turning it off whenever you get off your bike, this problem will NEVER happen to you again.

BTW:, you need to check your primary oil to see if it's been diluted as well. The gasoline will go past the sprocket shaft seal and contaminate that oil as well. You're pretty safe on the transmission lube though.

Good Luck
Steve (old biker)\\\\\

Jul 11, 2010 | 2000 Harley Davidson FLSTC Heritage...

1 Answer

When I went to start my 2005 Heritage Softail Classic after sitting for most of the winter, I found no oil on the dipstick. It was in operating range when I last rode it but now it will not register. Has...

Yes the oil will gravity feed out of the tank and into the crankcase. Disconnect the line on the bottom of the engine.Now make sure you put a little oil back in the tank.The oil will come out of the crankcase vent when you start the engine.. Be careful how much oil you put back in it cause it will return a little bit of it. If you do not drain the oil out it will go into the carburetor or throttle body depending what fuel delivery system you have and it will make a huge mess. That's the way Harley designed it for the E.P.A. to keep the oil off of the ground. I hope this was informative.

Mar 08, 2010 | 2003 Harley Davidson FLSTCI Heritage ...

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