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Discussion Starter · #1 ·
Ok 87 YJ, 258. I have oil and white smoke coming out of my Crankcase Breather hose. I have replaced the valve cover thinking maybe my baffles were all messed up and they were the front one was sucking up against the PCV valve, but even the new, stock Mopar valve cover didnt fix the problem. What else should I check? I'm checking the compression tomorrow, but the engine only has about 30,000 on a comeplete rebuild. If my compression test comes out OK then where should I go next? Oh yeah and my PCV valve is definitely working it has suction, but I don't know how much it really needs..it does pull your finger when you put it over it. I'm in college and this is my first jeep and I don't have the money for an engine swap or a complete rebuild...I hope to god it isn't that serious or I may never own a jeep again...

thanks in advance

 
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Discussion Starter · #2 ·
Well pull out that PCV and check it to make sure.. these things are cheap.. so its not a big deal to replace. Check your oil cap... is there any white gunk stuff around the neck?

78 CJ7 "Issues"
 

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Check for coolant in the oil and oil in the coolant. You are describing a cracked head. White smoke is usually coolant or lots of moisture being heated and boiled off.

 
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Discussion Starter · #4 ·
What would white gunk mean? I don't notice any around the oil cap, but I have noticed some up high on the dipstick, and, some very slight discoloration in the oil on the bottom tip of the dipstick??? And the oil has a "smell" to it...

 

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Yeah, but he said it was coming out of the breather hose, dudes, not the exhaust.

""I have oil and white smoke coming out of my Crankcase Breather hose""

How much? A lot? A little? Enough to fill a Corona bottle in 5 seconds? /wwwthreads_images/icons/wink.gif 3 hours?

Blowby typically comes out of the breather hose. If you can quantify the problem more, maybe we can help more.

How does it run? Does it run fine, just spew some oil out the breather?

Good luck,
Pete

88 YJ - trails/beach trips only!/wwwthreads_images/icons/smile.gif
79 4WD F250-hauler/tower of my toys
70 Jaguar E-type - the best car England ever made. /wwwthreads_images/icons/cool.gif
90 Honda CRX - Daily pavement-pounder. 42 MPG. /wwwthreads_images/icons/cool.gif
 
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Discussion Starter · #7 ·
Well let's see, it seems to me to be a bit underpowered, but then again I am running 32in. tires with stock 3.08 gears. But I still think its a little sluggish. About how much oil comes out..I'm not exactly sure I'd say about a quart a week, but I do a lot of stop and go driving, I do know that when you put your foot into a lot more white smoke comes than when idleing. I did recently blow a head gasket and had the block planed and put on a new head gasket but that was about 2 months ago and this has been a problem for about 6 or 7 months, but it's getting worse. Also it only holds about 15 18 pounds of oil pressure when the engine is good and hot at idle. When you are running down the highway it's about 36-40, and in this hot weather, with a 160 degree thermostat it still gets to about 210 degrees. But it's also about 90-95 degrees where I'm at now. I have to do what I can about it quickly or I'm afraid something bad is gonna happen.

 

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Ah, very well.

Well, as you said, she is gonna be a little underpowered with 32s and 3.08 gears. Why did you need a new head gasket and a block shave after only 30k? Could be something there, or it could just be blowby. A quart a week seems like a lot, but maybe that's just an estimate on your part.

I would most definitely do a compression check, and then rig up a catch bottle to catch the oil - see another post here, this was discussed in the past few days.

Watch your oil and water levels closely, and see what happens!

Good luck
Pete

88 YJ - trails/beach trips only!/wwwthreads_images/icons/smile.gif
79 4WD F250-hauler/tower of my toys
70 Jaguar E-type - the best car England ever made. /wwwthreads_images/icons/cool.gif
90 Honda CRX - Daily pavement-pounder. 42 MPG. /wwwthreads_images/icons/cool.gif
 
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Discussion Starter · #9 ·
I'll definitely do a compression check in the next few days, and I'll put a post on what I find then maybe we can figure out a problem from there.

Thanks for all the great Advice

John

 

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Here's a stupid question: Did they change the oil when the re-installed the head? It's kind of stupid to NOT change the oil, but I've heard of it happening. You might consider getting the oil changed today, then see if you develope the same problems. Just as a step in diagnosis....

DREW
IN2DEEP 78 CJ5
 
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Discussion Starter · #11 ·
I have changed the oil twice since then, I guess because fresh oil seems to hold better pressure then as it wears the pressure gradually drops week to week. So I change it about every 1500 miles.

 

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Pete, that stuff coming out the breather is one of two things:

1. Condensation from the oil pan, which I doubt.
2. Coolant from a crack.

The heads can crack some funny ways, like into the valve guide area, and let the coolant flow up onto outside of the heads while not entering the combustion chamber. It's rare, but it does happen. It would not be an overwhelming amount of coolant so it boils off easily and is sucked out the PVC.

One thing I did not remember to write was to waft you hand into that cloud of vapor. The stuff will coat the hand. Then you should be able to smell or taste the coolant. If there's no taste or smell of coolant it is probably condensation.

 
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Discussion Starter · #13 ·
The stuff coming out of the breather hose (white smoke) seems to have a strong exhaust smell to it...and it's not pure white...kinda hazy, with a little grayish tint to it.

 

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LEVE, ok, I guess I was just figuring most times it's coolant into the comb. chamber. Would coolant into the oil really boil out just sitting in the head? Wouldn't it just flow down to the pan? Oil is also going to float on the water/coolant, so you would see it come out first when you changed your oil. When you pull that pan plug, the first stuff to come out, if water's in there, is gonna be water.

Antoher thing to try, is to run the motor with the radiator cap loose - ala, no pressure in the coolant passages in the motor. It'll run ok this way, and still should stay cool in most instances. I ran my 67 impala this way for months because the radiator was bad and would leak with pressure. No pressure in the coolant passages should let less (or no) coolant flow through the crack, lessening or eliminating the smoke, if it's from a crack in the head. Just an experiment to run.

Good luck
Pete

88 YJ - trails/beach trips only!/wwwthreads_images/icons/smile.gif
79 4WD F250-hauler/tower of my toys
70 Jaguar E-type - the best car England ever made. /wwwthreads_images/icons/cool.gif
90 Honda CRX - Daily pavement-pounder. 42 MPG. /wwwthreads_images/icons/cool.gif
 
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Discussion Starter · #15 ·
I would like to thank everyone who has attempted to help with my problem, you all have been very helpful. I would like to especially thank "LEVE" and "PETE" you guys have more helpful. When I get done checking all this stuff out and check some more things out, I will get back to this post and hopefully I will have figured something out.
Thanks Everyone!

 
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