blowing oil up dipstick tube????? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

19mike69 · 06-05-2004, 08:19 PM

i have put 2 different new dipsticks on my 350 and for some reason oil keeps coming up the tube and leaking out of the top where the dipstick meets the tube.....what is causing this?I thought it might be the pcv valve,but with the truck running you can take it loose from the valve cover and it has alot of suction.Anybody ever had this problem?

**FRENCHBLUE72** · 06-05-2004, 08:28 PM

I have had this problem but never did find a soulution before the motor blew up.... And the motor blew up on my own stupidty not because of oil up the tube...

franko72 · 06-05-2004, 08:37 PM

You said that the Positive crankcase Ventilation valve is operating.You might check the source that feeds the ventilation, wether its a oil filler breather style cap or an element in the carb. breather.If your engine is not getting any circulation it could possibly be the culprit.Do you have any oil in the Carb. breather?If so you may need to rebuild.good luck.

19mike69 · 06-05-2004, 08:39 PM

well,thr guy at Autozone :p told me it was because the oil return drains in the heads were clogged.How would that affect it seeing as how the tube is lower than the heads to begin with?

franko72 · 06-05-2004, 08:52 PM

How is your crankcase getting circ air right now? is it at the carb breather or at the valve cover or at a oil fill tube?Check these for no air flow

19mike69 · 06-05-2004, 09:00 PM

im not for sure if i know what yall are talking about but the pcv valve is in the drivers side valve cover,and attached to it is a rubber hose that goes to the base of the carb (edelbrock 1406)....is it not supposed to be like that?I know if you touch your thumb to the pcv while the engine is running it sucks it pretty hard

Jeepster376 · 06-05-2004, 09:11 PM

Do you have a good vent on the other valve cover? At idle (high vac no load) you may have vacuum at your valve. But under heavy load you'll have less vacuum and more blowby. If there isn't a big enough vent it's probably looking for one.

franko72 · 06-05-2004, 09:14 PM

Yes the PVC valve should be connected just as you said.You should also have a seperate place ( other than the air going thru the Carb.)to get air feed circulation.check either valve cover for your oil fill opening.you will probably have an oil fill cap stuck into the valve cover. pull it out of the valve cover and turn it upside down.look at it to see if it has a breather opening under the cap.If it does it could be clogged. Second place to look is another larger vacuum hose or tube coming from the valve cover to a spacer between the carb. and the breather.third place to check is the same setup as before except the connection point is at the breather itself with a n element pad that might be clogged.happy hunting

19mike69 · 06-05-2004, 10:53 PM

i went out and looked right quick to see what i have...ok,on the drivers side i have the pcv on the front end of the valve cover and towards the rear of that side is the place to put in oil.But,it is the type of cap that is solid,there is no kind of vent or anything in it.Now on the passengers side the only thing is a rubber grommet in the valve cover towards the rear.I cant remember what used to be there,but i did but some rubber grommets and plugged up that hole.Does that particular hole need something else in it besides what i have?Is that where i need the other air source?I dont remember what was on that side,but i did plug it up.

70CST1 · 06-05-2004, 10:54 PM

Sounds Like Your Wigglin Pin In The Wobblin Shaft Might Need Adjusting.

Kid · 06-05-2004, 11:07 PM

replace the plug in the pass. side valve cover with a "push in" style filter vent, your motor needs a source for ventilation as franco72 posted.

Jeepster376 · 06-05-2004, 11:43 PM

Quote:

Originally Posted by 19mike69

I cant remember what used to be there,but i did but some rubber grommets and plugged up that hole.

Gotta have a vent there.

68LSS1 · 06-06-2004, 03:54 AM

You don't need to vent the other valve cover. You can but that isn't going to help or hurt anything. By venting the other valve cover it seems to me like you'd loose the effectiveness of creating the vaccuum to help seal the rings, which it's suppose to be doing. They quit venting the other valve cover years ago. Think about it, how is vaccuum (or the creation of pressure) on the top of the engine going to push oil out the dipstick tube? How many miles on the engine? Do a compression test and I think you'll find your answer.

jku72 · 06-06-2004, 05:51 AM

I'll bet the rings are bad.

68LSS1 · 06-06-2004, 05:56 AM

Quote:

Originally Posted by jku72

I'll bet the rings are bad.

My thoughts exactly

cdowns · 06-06-2004, 07:02 AM

YES YOU DO NEED A VENT IN THE PASS SIDE VALVE COVER FOR YOUR PVC SYSTEM TO OPERATE PROPERLY !!! bad rings HHHA HAHAHA !!!!

Truck Hippy · 06-06-2004, 07:28 AM

This is a picture of a factory type set up. PCV on one side and a hose running to the top of carb on the other. You may also want to check to see if the motor is clean inside. On the inside of the valve cover where the pcv valve goes, there is a small box or baffle. I had a motor one time that looked like it had 2 oil changes in about 20 years. It was almost clogged up. Oh, And thanks to who ever is the owner of the motor in the pic. Wes.

jku72 · 06-06-2004, 07:49 AM

The vent, if there is one, is there on the passenger side to prevent there from being excessive vacuum in the crank case. The whole point of the PCV system is to maintain a slight vacuum in the crankcase.
Incidentally, both my trucks have vents in the passenger side valve covers, but even those are positive vents that go into the suction side of the carb. I think that all stock engines in our trucks have both a PCV and the pass. valve cover vent to the air cleaner.
If there is still oil leaking out of the engine anywhere, it means that the pressure being created by blow-by is greater than the PCV system can handle. Thats worn broke or stuck rings.

Bowtie67 · 06-06-2004, 07:59 AM

Quote:

Originally Posted by 68LSS1

You don't need to vent the other valve cover. You can but that isn't going to help or hurt anything. By venting the other valve cover it seems to me like you'd loose the effectiveness of creating the vaccuum to help seal the rings, which it's suppose to be doing. They quit venting the other valve cover years ago. Think about it, how is vaccuum (or the creation of pressure) on the top of the engine going to push oil out the dipstick tube? How many miles on the engine? Do a compression test and I think you'll find your answer.

In some parts you are correct, some late model engines do have a completely sealed engine, pull the dipstick and the engine will run rough like it has a vacuum leak. but most engines require air to get in to circulate and to vent, the PCV just pulls the the vented pressure back in the motor to burn it. You don't need a PCV but at the expense of oil blowby making a mess of your engine compartment. MOst racers will put duel breathers in each valve cover. With no ventilation for the pressure to release could cause dipsticks to blow out of their holder or seals being blown out. If proper ventilation is there and there is oil blowing out the dipstick then there is deffinately an internal issue.

19mike69 · 06-06-2004, 12:05 PM

*laughing*...well,then i dont know what to do.As far as the motor goes,i have no idea what kind of shape its in.I do know it starts great and runs smoothly,but i dont know the condition of all of its internal parts.It may have 200,00 miles on it for all i know.If buying another vent for the pass side wont help,i wont buy one.I have an aftermarket breather like in the pic above and it has a place on the bottom side for a hose of some sort,but i have it plugged too.Will it help to get something from the pass side to the bottom of the breather or does the motor have something wrong inside?

franko72 · 06-06-2004, 12:08 PM

I thought that the purpose of crankcase ventilation is to keep the crankcase oil from bubbling due to ( spin washing of the crankshaft )splashing the oil and creating a kind of "suds" balance in the oil.If this happens the oil will not adhere to the parts that it is suppose to be protecting from friction heat, and could possibly wear out the bearings a little faster.You should have the supply and return on opposite sides of the motor to get a positive air flow thru the crankcase.

Kid · 06-06-2004, 01:00 PM

19mike69, I count 8 posts on this thread that tell you what you need to do. I'll bet ya, A $5 vent breather (simple filter or tube sucking from air cleaner) will fix your problem. Been there done that.....

tomsC10R · 06-06-2004, 02:46 PM

Mike,
Go buy a cheap a$$ breatehr and at least give it a shot.

Not a highjacking

Are you suppose to have the breather and pcv on certain sides of the engine? I've always had the pcv on the passenger side valve cover and the breather on the driver's side?

Jeepster376 · 06-06-2004, 04:46 PM

Quote:

Originally Posted by tomsC10R

Not a highjacking

Are you suppose to have the breather and pcv on certain sides of the engine? I've always had the pcv on the passenger side valve cover and the breather on the driver's side?

Functionally it doesn't make a difference, as long as it's one on each side. Which is "correct" as far as original is a different story.

19mike69 · 06-08-2004, 04:31 PM

well,i fixed it

i bought a $6 valve cover breather from autozone and it fixed it.Thanks for all the help and ideas
mike

06-05-2004, 08:19 PM	#1
19mike69 Registered User Join Date: Jul 2002 Location: pottsboro,tx Posts: 513	blowing oil up dipstick tube????? i have put 2 different new dipsticks on my 350 and for some reason oil keeps coming up the tube and leaking out of the top where the dipstick meets the tube.....what is causing this?I thought it might be the pcv valve,but with the truck running you can take it loose from the valve cover and it has alot of suction.Anybody ever had this problem? __________________ he who dies with the most toys wins...

06-05-2004, 08:37 PM	#3
franko72 Franko72 Join Date: May 2004 Location: Cincinnati,Ohio Posts: 471	You said that the Positive crankcase Ventilation valve is operating.You might check the source that feeds the ventilation, wether its a oil filler breather style cap or an element in the carb. breather.If your engine is not getting any circulation it could possibly be the culprit.Do you have any oil in the Carb. breather?If so you may need to rebuild.good luck. __________________ 1972 C20 cheyenne Super 402 BB/400 turbo LWB A/C Tilt, Cruise Control, Saddle tanks, Tach My Home Page Better to burn out than it is to rust

06-05-2004, 08:39 PM	#4
19mike69 Registered User Join Date: Jul 2002 Location: pottsboro,tx Posts: 513	well,thr guy at Autozone :p told me it was because the oil return drains in the heads were clogged.How would that affect it seeing as how the tube is lower than the heads to begin with? __________________ he who dies with the most toys wins...

06-05-2004, 08:52 PM	#5
franko72 Franko72 Join Date: May 2004 Location: Cincinnati,Ohio Posts: 471	How is your crankcase getting circ air right now? is it at the carb breather or at the valve cover or at a oil fill tube?Check these for no air flow __________________ 1972 C20 cheyenne Super 402 BB/400 turbo LWB A/C Tilt, Cruise Control, Saddle tanks, Tach My Home Page Better to burn out than it is to rust

06-05-2004, 09:00 PM	#6
19mike69 Registered User Join Date: Jul 2002 Location: pottsboro,tx Posts: 513	im not for sure if i know what yall are talking about but the pcv valve is in the drivers side valve cover,and attached to it is a rubber hose that goes to the base of the carb (edelbrock 1406)....is it not supposed to be like that?I know if you touch your thumb to the pcv while the engine is running it sucks it pretty hard __________________ he who dies with the most toys wins...

06-05-2004, 08:28 PM	#2
FRENCHBLUE72 PROJECT 7DEUCE Join Date: Dec 2002 Location: GRANTS PASS OR Posts: 21,608	I have had this problem but never did find a soulution before the motor blew up.... And the motor blew up on my own stupidty not because of oil up the tube...

06-05-2004, 09:11 PM	#7
Jeepster376 Registered User Join Date: Feb 2004 Location: Massachusetts Posts: 269	Do you have a good vent on the other valve cover? At idle (high vac no load) you may have vacuum at your valve. But under heavy load you'll have less vacuum and more blowby. If there isn't a big enough vent it's probably looking for one. __________________ 72 Cheyenne Super 4x4 SWB

06-05-2004, 09:14 PM	#8
franko72 Franko72 Join Date: May 2004 Location: Cincinnati,Ohio Posts: 471	Yes the PVC valve should be connected just as you said.You should also have a seperate place ( other than the air going thru the Carb.)to get air feed circulation.check either valve cover for your oil fill opening.you will probably have an oil fill cap stuck into the valve cover. pull it out of the valve cover and turn it upside down.look at it to see if it has a breather opening under the cap.If it does it could be clogged. Second place to look is another larger vacuum hose or tube coming from the valve cover to a spacer between the carb. and the breather.third place to check is the same setup as before except the connection point is at the breather itself with a n element pad that might be clogged.happy hunting __________________ 1972 C20 cheyenne Super 402 BB/400 turbo LWB A/C Tilt, Cruise Control, Saddle tanks, Tach My Home Page Better to burn out than it is to rust

06-05-2004, 10:53 PM	#9
19mike69 Registered User Join Date: Jul 2002 Location: pottsboro,tx Posts: 513	i went out and looked right quick to see what i have...ok,on the drivers side i have the pcv on the front end of the valve cover and towards the rear of that side is the place to put in oil.But,it is the type of cap that is solid,there is no kind of vent or anything in it.Now on the passengers side the only thing is a rubber grommet in the valve cover towards the rear.I cant remember what used to be there,but i did but some rubber grommets and plugged up that hole.Does that particular hole need something else in it besides what i have?Is that where i need the other air source?I dont remember what was on that side,but i did plug it up. __________________ he who dies with the most toys wins...

06-05-2004, 10:54 PM	#10
70CST1 Registered User Join Date: Apr 2003 Location: south central kentucky Posts: 444	Sounds Like Your Wigglin Pin In The Wobblin Shaft Might Need Adjusting. Attached Images

06-05-2004, 11:07 PM	#11
Kid Senior Member Join Date: Jun 2002 Location: Kansas Posts: 702	replace the plug in the pass. side valve cover with a "push in" style filter vent, your motor needs a source for ventilation as franco72 posted. __________________ The kid Build threads: 51 Jimmy http://67-72chevytrucks.com/vboard/s...d.php?t=154951 http://67-72chevytrucks.com/vboard/s...d.php?t=219902 http://www.classictrucks.com/feature...uck/index.html 68 C10 http://67-72chevytrucks.com/vboard/s...ad.php?t=50348

06-06-2004, 03:54 AM	#13
68LSS1 Registered User Join Date: Dec 2002 Location: Tampa Posts: 1,191	You don't need to vent the other valve cover. You can but that isn't going to help or hurt anything. By venting the other valve cover it seems to me like you'd loose the effectiveness of creating the vaccuum to help seal the rings, which it's suppose to be doing. They quit venting the other valve cover years ago. Think about it, how is vaccuum (or the creation of pressure) on the top of the engine going to push oil out the dipstick tube? How many miles on the engine? Do a compression test and I think you'll find your answer. __________________ '68 Short Step LS1/T56, Hydratech, Fatman Fabrications Stage III, Baer, Hot Rods to Hell, US Body, S&W, etc

06-06-2004, 05:51 AM	#14
jku72 Registered User Join Date: Jan 2002 Location: cornville, maine Posts: 659	I'll bet the rings are bad. __________________ jku Cornville, Maine 68 C10 burb 42 Willys MB 46 Dodge WF-32 1.5 ton 53 & 56 Olds' 60 Cadillac 22 Dodge Brothers

06-06-2004, 07:02 AM	#16
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	YES YOU DO NEED A VENT IN THE PASS SIDE VALVE COVER FOR YOUR PVC SYSTEM TO OPERATE PROPERLY !!! bad rings HHHA HAHAHA !!!! __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

06-06-2004, 07:28 AM	#17
Truck Hippy Registered User Join Date: Aug 2002 Location: Hickory, NC. Posts: 776	This is a picture of a factory type set up. PCV on one side and a hose running to the top of carb on the other. You may also want to check to see if the motor is clean inside. On the inside of the valve cover where the pcv valve goes, there is a small box or baffle. I had a motor one time that looked like it had 2 oil changes in about 20 years. It was almost clogged up. Oh, And thanks to who ever is the owner of the motor in the pic. Wes. Attached Images



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06-06-2004, 07:49 AM	#18
jku72 Registered User Join Date: Jan 2002 Location: cornville, maine Posts: 659	The vent, if there is one, is there on the passenger side to prevent there from being excessive vacuum in the crank case. The whole point of the PCV system is to maintain a slight vacuum in the crankcase. Incidentally, both my trucks have vents in the passenger side valve covers, but even those are positive vents that go into the suction side of the carb. I think that all stock engines in our trucks have both a PCV and the pass. valve cover vent to the air cleaner. If there is still oil leaking out of the engine anywhere, it means that the pressure being created by blow-by is greater than the PCV system can handle. Thats worn broke or stuck rings. __________________ jku Cornville, Maine 68 C10 burb 42 Willys MB 46 Dodge WF-32 1.5 ton 53 & 56 Olds' 60 Cadillac 22 Dodge Brothers

06-06-2004, 12:05 PM	#20
19mike69 Registered User Join Date: Jul 2002 Location: pottsboro,tx Posts: 513	laughing...well,then i dont know what to do.As far as the motor goes,i have no idea what kind of shape its in.I do know it starts great and runs smoothly,but i dont know the condition of all of its internal parts.It may have 200,00 miles on it for all i know.If buying another vent for the pass side wont help,i wont buy one.I have an aftermarket breather like in the pic above and it has a place on the bottom side for a hose of some sort,but i have it plugged too.Will it help to get something from the pass side to the bottom of the breather or does the motor have something wrong inside? __________________ he who dies with the most toys wins...

06-06-2004, 12:08 PM	#21
franko72 Franko72 Join Date: May 2004 Location: Cincinnati,Ohio Posts: 471	I thought that the purpose of crankcase ventilation is to keep the crankcase oil from bubbling due to ( spin washing of the crankshaft )splashing the oil and creating a kind of "suds" balance in the oil.If this happens the oil will not adhere to the parts that it is suppose to be protecting from friction heat, and could possibly wear out the bearings a little faster.You should have the supply and return on opposite sides of the motor to get a positive air flow thru the crankcase. __________________ 1972 C20 cheyenne Super 402 BB/400 turbo LWB A/C Tilt, Cruise Control, Saddle tanks, Tach My Home Page Better to burn out than it is to rust

06-06-2004, 01:00 PM	#22
Kid Senior Member Join Date: Jun 2002 Location: Kansas Posts: 702	19mike69, I count 8 posts on this thread that tell you what you need to do. I'll bet ya, A $5 vent breather (simple filter or tube sucking from air cleaner) will fix your problem. Been there done that..... __________________ The kid Build threads: 51 Jimmy http://67-72chevytrucks.com/vboard/s...d.php?t=154951 http://67-72chevytrucks.com/vboard/s...d.php?t=219902 http://www.classictrucks.com/feature...uck/index.html 68 C10 http://67-72chevytrucks.com/vboard/s...ad.php?t=50348

06-06-2004, 02:46 PM	#23
tomsC10R Registered User Join Date: Nov 2003 Location: Wisconsin Posts: 281	Mike, Go buy a cheap a$$ breatehr and at least give it a shot. Not a highjacking Are you suppose to have the breather and pcv on certain sides of the engine? I've always had the pcv on the passenger side valve cover and the breather on the driver's side? __________________ Tom 1968 C10 LWB. 402 BB, Holley MPI, 700R4. 4wheel Hydroboost Disk Brakes.

06-08-2004, 04:31 PM	#25
19mike69 Registered User Join Date: Jul 2002 Location: pottsboro,tx Posts: 513	well,i fixed it i bought a $6 valve cover breather from autozone and it fixed it.Thanks for all the help and ideas mike __________________ he who dies with the most toys wins...

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