78 shovelhead primary help
Tourer
Joined: Jun 2008
Posts: 306
Likes: 7
From: Somewhere, PA
I haven't read through the entire thread while here at work, so forgive me if this has already been addressed. When I see guys blowing out their oiltank dipsticks, it's often related to their engine breather (the CASE breather) being clogged. Some guys run crappy filters on the end of the breather hose, which clog with oil and dirt and then quit working. When this happens, the engine WILL find a way to vent pressure, which sometimes happens to be the vent hose to the oil tank. For this reason I always tell everyone to take the filter off the end, as it really serves no purpose anyway, and just vent through the hose. If it happens to spray some oil mist like some bikes do, then direct it over the chain and out of the way of the rear tire.
Just a thought. Let us know what you find - sorry to only see this thread today...
Just a thought. Let us know what you find - sorry to only see this thread today...
Road Captain
Joined: Apr 2010
Posts: 692
Likes: 34
From: Texas
Come and take it - what do you think would happen if you took the cap to your oil tank off while the engine was running?
Of course you should be able to do that and not have any issues - what you should see is oil flowing into the tank. I would ask you to do it, but don't want to get hammered for getting oil all over the place.
Do you have an oil cooler on your bike?
Maybe you should trace each line from the oil tank to its destination and make a note of it.
If you have an oil cooler make note of where the two hoses from it terminate;
At the oil pump, make note of each outlet and where terminates. also make note of any lines on the pump which are plugged/capped.
Let us read your notes.
Of course you should be able to do that and not have any issues - what you should see is oil flowing into the tank. I would ask you to do it, but don't want to get hammered for getting oil all over the place.
Do you have an oil cooler on your bike?
Maybe you should trace each line from the oil tank to its destination and make a note of it.
If you have an oil cooler make note of where the two hoses from it terminate;
At the oil pump, make note of each outlet and where terminates. also make note of any lines on the pump which are plugged/capped.
Let us read your notes.
Intermediate
Joined: Aug 2010
Posts: 45
Likes: 0
From: Richmond, TX
I've replaced all the oil lines on this bike according to info i've found here and on other sites. I recently sealed the primary and removed the vent line and T from the primary...Now that line runs straight from oil pump/engine to the oil tank. When I remove the dipstick when running, there's an obvious vapor trail coming from the tank...poof poof poof in time with the engine. I'll double check all routing and make sure the case vent line is clear and then report back.
Thanks for the help guys.
Thanks for the help guys.
Intermediate
Joined: Aug 2010
Posts: 45
Likes: 0
From: Richmond, TX
Problem solved. The case vent line had a really sharp turn in it, and had developed a blockage there. I re-routed it up against the frame and installed a stainless filter. It looks good, runs great, and doesn't blow out the dipstick any more!!! HAHAHA!
Road Captain
Joined: Apr 2010
Posts: 692
Likes: 34
From: Texas
Glad you found the source, but would dump the filter on the case vent line. Shovels puke a little oil from there from time-to-time. Eventually, that vent is going to clog. Now some guys run a hose from the case vent and let it dump on the chain.
Intermediate
Joined: Aug 2010
Posts: 45
Likes: 0
From: Richmond, TX
I've eliminated anything going to the chain and just use a good off-road chain wax. Otherwise it throws oil all over my wide white walls.
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Road Captain
Joined: Apr 2010
Posts: 692
Likes: 34
From: Texas
I am guessing you have an O-ring chain.
Point is don't restrict that crankcase vent with a filter. Just use a short piece of hose. If the bike is being ridden regularly, very little if any oil will drip from it. If the bike has been sitting for a while, then remember to put a bucket under it in the event it sumps a bunch of oil, which is a common occurrence for shovels.
Point is don't restrict that crankcase vent with a filter. Just use a short piece of hose. If the bike is being ridden regularly, very little if any oil will drip from it. If the bike has been sitting for a while, then remember to put a bucket under it in the event it sumps a bunch of oil, which is a common occurrence for shovels.
Club Member
Joined: Mar 2009
Posts: 66,126
Likes: 51,457
From: Niles Canyon Ca.
I am guessing you have an O-ring chain.
Point is don't restrict that crankcase vent with a filter. Just use a short piece of hose. If the bike is being ridden regularly, very little if any oil will drip from it. If the bike has been sitting for a while, then remember to put a bucket under it in the event it sumps a bunch of oil, which is a common occurrence for shovels.
Point is don't restrict that crankcase vent with a filter. Just use a short piece of hose. If the bike is being ridden regularly, very little if any oil will drip from it. If the bike has been sitting for a while, then remember to put a bucket under it in the event it sumps a bunch of oil, which is a common occurrence for shovels.
The man's right about that one if she sit's for more than a week put a pan under the breather hose , she will blow some out . The check ball holding the oil up in the tank always seeps by , it was the biggest reason harley went to oil bags under the trannys in the newer bikes to finally solve the that problem .
