Where's my oil going?

[MrShoeBoy]

I have no leaks on the ground, no streeks of oil on the bottom, coolent is clean, and no large puffs of blue smoke out the tail pipe. On first cold startup, there is the slightest hint of blue smoke but it immediatly goes away. The tail pipe is not oily but does have some soot on it. There is no noticable loss of power or any other negative effects.

I loose a quart of oil per 500 to 1000 miles. The motor was rebuilt 2 years ago and it has maybe 10k on it since the rebuild.

How would I determine if this is bad valve seals or piston rings?

The motor was rebuilt it was bored over .030, bigger cam, self ported and polished head, portmached intake and exhaust to head, bored T-body and spacer, custom intake with K&N filter, highflow cat and flowmaster. Since the motor is not stock, I figured it would fit into the Modified tech forum

Thanks,

AARON

 

[MrShoeBoy]

So nobody has any ideas?

 

[pancake]

wet and dry compression check

 

[Mikel]

I was burning 1qt of oil every 1000 miles in a Mitsu Eclipse, and the blue smoke was VERY obvious.

 

[MrShoeBoy]

wet and dry compression check

That is what I plan on doing next. Just havent had the time to check and also I need to borrow a compression checker from a friend.

AARON

 

[MudDawg]

Has the engine ever overheated on you??? Do you do regular oil changes??The puff of smoke at start-up indicates leaky valveguide seals...and it does not have to visibly smoke to use oil...Get a leakdown test done to indicate piston/rings/cylinder sealing..read the plugs or have them read by a competent race engine tuner...If you can access a borescope you can inspect the cylinder walls for obvious damage. I just hope you haven't spent a large amount of time in severe dust conditions with a oiled gause air filter...

The original engine in my XJ used a quart every 300 miles...the exhaust pipe was dry and sooty...when i tore it down...one piston and cylinder had scored from overheating and they were all worn out in general from lack of maintenance..

 

[MrShoeBoy]

My XJ gets routine maintence earlier than recomended. I tend to use it hard and in doing so, take care of it better. The oil is changed along with the filter every 3k with Moble 1 10w-30 and everything else is greased and checked to make sure all the suspension bolts are tight as well as check all fluids.

It got "really" hot only once on a trail ride but the needle never crossed into the red zone on the gauge. My aux fan fuse blew. Now granted that the gauge is not accurate, nothing boiled over and my oil temp gauge didnt go above 220 degrees. I have an Autometer oil temp gauge installed in the oil pan so I know oil temp is accurate.

Thanks,

AARON