Uh Oh! Think I may have a problem here! (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Apr 6, 2003
Threads
103
Messages
750
Location
Tomball, TX
Went to do a little work on the Cruiser today and decided to check the oil. Was down 1.5 quarts or so - never happended before. However, I've been noticing a problem with it blowing black crap out of the exhaust pipe upon startup, usually all over the side of my wife's white Jetta. She loves that by the way. The black crap appears to be oily? Smears pretty bad when you go to wipe it off with your finger. The 2F supposedly has 106,000 miles on it according to the PO. I have had it for 9 months or so, and just changed the weight of the motor oil from 5w-30 to 10w-40 at the last oil change and the problem seems more predominant now. Could it be blowing oil out of the exhaust pipe? Is this what is commonly referred to as "blow by"? If so, how much time do I have before a rebuild is needed? ???
 
The black stuff is carbon from the engine running rich while the choke is out. That's normal. Blue smoke on start up or on acceleration is a worn motor. Valves or rings. Blue smoke all of the time is a whupped motor or possibly a PCV problem. Check your air cleaner for oil. If it's oily, check the PCV valve.
Blow by is combustion gasses leaking past the piston rings into the crankcase. It happens on all engines and the PCV releases that pressure. The more worn out the compression rings, the more blow by. Thicker oil will help this problem a little. If the PCV is stuck, the engine can pump oil into the air filter housing where it will clog the air filter and get burned in the combustion chambers.
There is no way to tell from your description how much time is left before a rebuild. A compression check and oil pressure numbers could give us a decent idea, but without that info, your engine could have from 100 miles to 200,000 miles left depending on how you and the PO maintain and drive it.
 
I used to get quite a bit of that black crap all over the garage floor and wall (made my parents happy) but then I switched to 20w 50 from 10w 40 and don't have any of that anymore. I switched because of oil pressure, not that black crap though.
 
Thanks CruisinGA and Gumby. :D

CruisinGA,
My oil pressure is 40-45 psi@ at about 2700 rpm. and about 20psi@1000 rpm(idle). Wonder if it is just running a little rich? It still throws black crap when I don't use the choke, which is most of the time because it doesn't get very cold down here in Texas, and it fires up fine without the choke 90% of the time. Doesn't blow any noticeable blue smoke upon statring or acceleration, but maybe need to have someone follow me to see if it blows a little between shifts. I'll probably follow Gumby and use heavier weight oil at the next change and see what that does. Have either of you ever used the Lucas Oil additive before? Noticed it today and wonder if it would do any good. i suspect it isn't much more than a Viscosity Improver, which would be equivalent to changing to a heavier oil. Let me know what you think about the oil pressure numbers above. Thanks.
 
I can't really comment on the numbers because I am still in the dark ages with my original guages 8), However, I have used the Lucas stuff before, gave good results as far as raising my oil pressure with 10w-40 in the sump. I got better results from just switching to 20w-50. If I were you I would give a quart of the lucas stuff a shot, just dump it in there above what you got now, and see if there is any improvement before switching to 20w-50.
 

Users who are viewing this thread

Back
Top Bottom