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Old 09-02-2013, 11:35 PM   #1
Jdbfish
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Engine blowing oil around carb onto intake

My engine is blowing oil out all over the place. It's pooling up on the intake under the breather on both sides of the carb. Any ideas what's causing this? Casting number cross references to 307 but the guy I got it from says its a 350 with a fairly recent overhaul. I'm not sure....
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Old 09-03-2013, 12:04 AM   #2
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Re: Engine blowing oil around carb onto intake

So...wheres it coming from? It might be something as simple as loose intake bolts.
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Old 09-03-2013, 12:12 AM   #3
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Re: Engine blowing oil around carb onto intake

Wide side: hello from just up the road a bit!!!! I wished I knew where it was coming from. I don't think it's intake bolts because there are no water leaks or apparent vacuum/air leaks because it runs ok but I will check for sure tomorrow. I hope it's something simple and not major. Could it be a major issue?????
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Old 09-03-2013, 12:28 AM   #4
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Re: Engine blowing oil around carb onto intake

Intake bolts can leak oil even if they're tight, and without air or water leaks. Some of the bolts extend into the lifter galley. Can't recall which bolts need thread sealer..... hopefully someone will jump in. Or just seal them all to be sure.
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Old 09-03-2013, 02:33 AM   #5
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Re: Engine blowing oil around carb onto intake

My first thought was no sealant on the intake bolts, Most intakes need to be re torqued after a bit of run time.

Do you have a copper oil line running to the oil pressure gauge? make sure its not got a pin hole and spraying oil (yea i just come up with any other possible source of oil, seem pretty far fetched)
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Old 09-03-2013, 04:24 AM   #6
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Re: Engine blowing oil around carb onto intake

Yes copper line, I will check that to. I'm really worried because I read some info on this when I googled it and many say it is caused by blow by due to bad piston rings, etc, any thoughts on that? Is that possible?
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Old 09-03-2013, 05:48 AM   #7
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Re: Engine blowing oil around carb onto intake

Forgot to mention that oil pressure is good when cold but gage bottoms out when hot at idle but jumps right back up and pegs out when u give it gas
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Old 09-03-2013, 07:58 AM   #8
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Re: Engine blowing oil around carb onto intake

What do you have for crankcase ventilation? Are the valve covers n& air cleaner original? Is there a tube to the filter housing from the valve cover and a PCV valve on the other side? If it has aftermarket valve covers & air cleaner,what's there for venting? If you have a PCV valve,is it clogged?
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Old 09-03-2013, 08:01 AM   #9
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Re: Engine blowing oil around carb onto intake

Gonna need some pics here.
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Old 09-03-2013, 08:12 AM   #10
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Re: Engine blowing oil around carb onto intake

Ill get some pics together later today. I will look at the crankcase ventilation as well....
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Old 09-03-2013, 08:39 AM   #11
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Re: Engine blowing oil around carb onto intake

Could also be as simple as valve cover gaskets though they usually leak on the outside.However I have seen people tighten them too much on the outter bolts and cause a leak on the intake side.
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Old 09-03-2013, 09:29 AM   #12
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Re: Engine blowing oil around carb onto intake

The two center intake bolts on both sides go into the lifter valley and need sealant or they will leak.
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Old 09-03-2013, 09:34 AM   #13
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Re: Engine blowing oil around carb onto intake

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What do you have for crankcase ventilation? Are the valve covers n& air cleaner original? Is there a tube to the filter housing from the valve cover and a PCV valve on the other side? If it has aftermarket valve covers & air cleaner,what's there for venting? If you have a PCV valve,is it clogged?
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Old 09-03-2013, 01:32 PM   #14
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Re: Engine blowing oil around carb onto intake

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The two center intake bolts on both sides go into the lifter valley and need sealant or they will leak.
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This is common and an easy fix........
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Old 09-03-2013, 10:05 PM   #15
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Re: Engine blowing oil around carb onto intake

Those intake bolts can leak (seep),but not how the author of this thread describes.
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Old 09-03-2013, 11:10 PM   #16
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Re: Engine blowing oil around carb onto intake

Not sure what's going on yet, did not get a chance to look into it today. The oil seems to pool up more on the drivers side than the passenger side. Ther reason I say it's "spraying is because there is a light film of oil on the underside of the breather and on the carb, valve cover and intake all around the carb area. Confused!!!!!
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Old 09-03-2013, 11:24 PM   #17
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Re: Engine blowing oil around carb onto intake

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Old 09-03-2013, 11:26 PM   #18
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Re: Engine blowing oil around carb onto intake

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Old 09-03-2013, 11:32 PM   #19
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Re: Engine blowing oil around carb onto intake

You absolutely certain it is oil, and not coolant that has mixed with grime to become that color?
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