Removing oil cap - 2004 Harley Davidson XL 1200 C Sportster Custom

I suspect two problems. Vacuum when removing oil cap is likely PCV valve. No oil pressure could either be true, and caused by oil pump or clog, or not true, caused by bad sensor.

What vehicle?

What cap & where?

You remove the oil pan drain plug

oil bubbles ? oil splashes under valve covers across the valve train opening the valve cap may get oil splash-- but oil bubbles oil may foam a bit from being old or if coolant got in it and wouldnt bubble out of cap but bubbles --- and oil splash is normal when opening oil cap with vehicle running

Hello, the oil filter location is on the front of the engine, just below the right side of intake manifold.

Use a 32 mm (1 1/4 in) socket on the hex on top of the oil filter cap, or an oil filter wrench on the outside diameter of the oil filter cap.

Remove the oil filter cap and filter.

Remove the filter from the cap.

no you will not be the first one to do it
as long as you copped it and did not run engine without oil should be okay top up to proper level put cap on should be okay
oil will blow out cap removed normal

and???????????

rip the top of the cap off, then use a pair of channel locks to remove the rest of the cap it unscrews counterclock wise.

Solved the problem by taking it to a shop and being overcharged to have a tech remove it with pliers and breaking it in the process. Had to buy yet another new oil cap. Problem not solved cause this new cap won't budge either.

PLASTIC HOUSING ON LOWER FRONT OF ENGINE

did you check the pulley on the crank shaft ??
is it warped ?? ( bent )
because i do not think that the truck will run with the crankshaft moving.....back and forth.
so in any case you have a lot of work to do.
here is how to remove the crank shaft.
REMOVAL

1. Remove the oil pan.
2. Remove the oil pump from the rear main bearing cap.
3. Remove the vibration damper.
4. Remove the timing chain cover.
5. Identify bearing caps before removal. Remove bearing caps and bearings one at a time.
6. Lift the crankshaft out of the block.
7. Remove and discard the crankshaft rear oil seals.
8. Remove and discard the front crankshaft oil seal.

INSTALLATION

1. Lightly oil the new upper seal lips with engine oil.
2. Install the new upper rear bearing oil seal with the white paint facing towards the rear of the engine.
3. Position the crankshaft into the cylinder block.
4. Lightly oil the new lower seal lips with engine oil.
5. Install the new lower rear bearing oil seal into the bearing cap with the white paint facing towards the rear of the engine.
1. Apply 5 mm (0.20 inch) drop of Loctite 518, or equivalent, on each side of the rear main bearing cap. DO NOT over apply sealant or allow the sealant to contact the rubber seal. Assemble bearing cap to cylinder block immediately after sealant application.
2. lb align the bearing cap, use cap slot, alignment dowel and cap bolts. DO NOT remove excess material after assembly. DO NOT strike rear cap more than 2 times for proper engagement.
3. Clean and oil all cap bolts. Install all main bearing caps. Install all cap bolts and alternately tighten to 115 Nm (85 ft. lbs.) torque.
4. Install oil pump.
5. Install the timing chain cover.
6. Install the vibration damper.
1. Apply Mopar Silicone Rubber Adhesive Sealant, or equivalent, at bearing cap to block joint to provide cap to block and oil pan sealing. Apply enough sealant until a small amount is squeezed out. Withdraw nozzle and wipe excess sealant off the oil pan seal groove.
2. Install new front crankshaft oil seal.
3. Immediately install the oil Dan.

if you have an email address i can send some images