blowing oil out my dipstick tube????

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swinger340

swinger340

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Fairly fresh 10:1 340, 202 J heads, MP .484 cam. Has about 1500 miles on it now. Quick revs to 5500-6000 it pushes the dipstickout of the tube and spits oil out the tube. Never did this last year. Dipstick fits in tube a little loose but there should not be pressure there anyways. Oil seems a little thin and may be like a pint over. Anyone have this happen to them? Any ideas? PVC in 1 cover and breather in the onther
 
Not enough breathers

rings not sealing up well.
 
at that rpm pcv will not help...breathers are needed or some kind of crank case evacuation...

pcv work good with high vacuum ....
 
swinger340 said:
Fairly fresh 10:1 340, 202 J heads, MP .484 cam. Has about 1500 miles on it now. Quick revs to 5500-6000 it pushes the dipstick tube out a little and spits oil out the tube. Never did this last year. Dipstick fits in tube a little loose but there should not be pressure there anyways. Oil seems a little thin and may be like a pint over. Anyone have this happen to them? Any ideas? PVC in 1 cover and breather in the onther
Click to expand...
does your oil get dark quickly?using alot oil?if yes to both id suspect ring seal.you could try switching to an open element breather.
 
340 8BBL said:
does your oil get dark quickly?using alot oil?if yes to both id suspect ring seal.you could try switching to an open element breather.
Click to expand...
Oil stays pretty clean. It dont use any oil or smoke@ all. Good cylinder pressure, (150lbs) all within a couple lbs of each other. Im thinking a ventalation problem, but it didnt do it last summer, Thats what is throwing me off. Would thicker oil make it better or worse? 10/40 now but it looks like water.
 
Check to make sure your breather hoses have not gotten soft and collapsed internally.
Also clean or replace your PVC valve and make sure the connections on your valve covers are clear.
 
swinger340 said:
Oil stays pretty clean. It dont use any oil or smoke@ all. Good cylinder pressure, (150lbs) all within a couple lbs of each other. Im thinking a ventalation problemm buy it didnt do it kast summer, Thats what confuses me. Would thicker oil make it better or worse? 10/40 now but it looks like water.
Click to expand...
the filter media in your breather may be saturated/plugged.try an open element breather.you said the oil is slightly over filled and thin like water.does the oil smell strongly of fuel?
 
340 8BBL said:
...you said the oil is slightly over filled and thin like water.does the oil smell strongly of fuel?
Click to expand...
Yeah, if it's making oil I would be more concerned about that than anything else at this point.
 
same as other advice - i'd check the breather itself, hose for kinks, etc- had it happen to me and kinda occurred suddenly -crankcase pressure and actually blew oil out from the front intake cork seal all over the fan then up all over the underside of the hood - I replaced the valve cover breather and cured the problem
 
Rather than a compression test, try a leak down test. It's a better indicator of actual ring seal ability. If it's pushing oil and already has a PCV system intact it has too much pressure IMO.
 
Got it straightened out. Oil smelt gasy so i changed it (float stuck on me couple of weeks ago, have since rebuilt the carb.). pvc hose was fitting loose on carb, so i changed it out. Valve cover breather was hard to blow through so i swaped that out as well. One of the 3 did it. Dont do it now. Thanks for all the input.
 
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