Question about Harley Davidson Harley-Davidson Motorcycle Desktop Telephone

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Oil cap blasting off

I have a 89 883 sportster. i recently pulled the gastank and carb to clean, as the tank had rust in it. it now runs fine,except while test riding it the oil cap shot off(obviously back pressure in the oil tank). water in gas?, timing? any suggestions? i have put "heet" in w/ the gas.

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Re: oil cap blasting off

Worn or stuck piston compression ring may also cause an increase crankcase's pressure.

Posted on Jan 15, 2008

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Re: oil cap blasting off

Your crankcase is not breathing right. Re-Check your lines going into the air filter back plate, make sure the lines are not kinked in any way. Also make sure the lines are not dry rotted.
The Rev. Kid Kev

Posted on Dec 29, 2007

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2003 Fatboy while winterizing drained the oil very little came out however there was oil in filter..New filter,filled with oil started sounds like usual then the oil shot out of the cap where you insert...

On the softail model Harley Davidson's the oil tank is external and sits up higher than the engine crank case and oil pump. when these bikes sit for an amount of time the oil gravitates from the tank to the crank case. starting may seem sightly harder and seem like the battery is going dead. the bike should be started in knowing that you had oil in it to start with and no giant leak puddle underneath of it. warm up the engine and then drain the oil out of the tank. the reason why your filler cap popped off is because you had probably 2 1/2 to 3 quarts to much engine oil in the bike. so drain the oil from the tank at the drain pug at the bottom of the hose on the high (right side ) of the bike where the swing arm meets the frame (it is a 5/8 socket) put the drain plug back in run the bike for about 5 minutes inspecting with a flashlight continuously that oil is circulating back into the tank. then dran it again and replace with new oil.

Dec 10, 2010 | Harley Davidson Harley-Davidson Motorcycle...

1 Answer

How do you check oil level in a 2001 Harley Davidson Sportster

There should be a removable plug in th oil tank. Jut pull it out and look in, the oil level should be just below the neck of the hole the plug goes in.

May 05, 2010 | Harley Davidson Harley-Davidson Motorcycle...

1 Answer

Rideing my harley sportster 1992 another day and the oil dip stick blowout of the oil tank must have to much presser but the motor runs smooth no missing idil well do they a breather somwhere

overfull or your rubber cap bushing is worn if you were beating on it when it came out its probably in need of a new cap but do check the oil level hot they dont always drain completly so they wont take what the manual calls for

Dec 14, 2009 | Harley Davidson Harley-Davidson Motorcycle...

2 Answers

Bike wont idle without choke

you need to take your carb off give it as good cleaning. also check your intake gaskets where the manifold joins the jugs and the black rubber one where the carb joins the manifold. You def have air/fuel problem going on. also check your vscume hose to the carb but im thinking that is not it.

Sep 23, 2009 | Harley Davidson Harley-Davidson Motorcycle...

1 Answer

Turns over but will not start

carb needs to be cleaned and adjusted properly

Apr 15, 2009 | Harley Davidson Harley-Davidson Motorcycle...

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200 Harley 1200 Sportster, Shuts off when at idle at stoplight / stopsign, etc.


Offhand and initially, pls start by referencing the steps as outlined here.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information. Good luck and kind regards. Thank you for using FixYa.

Nov 08, 2008 | Harley Davidson Harley-Davidson Motorcycle...

1 Answer

Oil amount

It's going to hold approx 3 quarts. The dipstick is irrelevant, the level should be just bellow the bottom of the filler tube, about a half inch, so you should be able to see the oil when you remove the cap. I'm not sure why HD even puts the dipstick on the cap.

Aug 29, 2008 | Harley Davidson Harley-Davidson Motorcycle...

3 Answers

Map sensor


Have not worked on an HD but my thoughts and additional guesses would be:
1. fuel contamination (water at bottom of tank);
2. primary pump (in my case it was inside the fuel tank & might not be present in your bike);
3. fuel lines & clamps to & from primary pump or to the carbs;
4. in line filters;
5. vacuum controlled fuel valve (oppose to the usual manual petcock)
6. if it were the MAP sensor, bike wouldn't even run a block away + idling would be rough;
7. by chance are you using a Power Commander?

Also your post "bike will start and run fine for a few blocks then die" indicates that indeed fuel got into the carbs before but not when running meaning the bike used what was inside the bowl and was not replenished.  Alternately, the fuel flow to the carbs might not be sufficient and there is a leak or a blockage somewhere.

As said might not work for your bike but has come across some of the above on numerous occasions.

Good luck and Kind regards.

Ride Safe.

Oct 23, 2007 | Harley Davidson Harley-Davidson Motorcycle...

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