360 LA getting oil in #3 cylinder.

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Rat Bastid said:
Fuel atomization and vaporization is a big problem with todays fuel (blended for EFI) and cold air intakes.

I won’t do a cold air intake without a quality annular boosters any more.

As a general rule, that series of carbs were “universal” which means they universally fit nothing.

The idle circuit is so rich it’s crazy. Like most everything else they need T slot restricters.

They need some work but if you tune them they work well.
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Thank you. Looks like I need to switch back to more street friendly parts.
 
tinman2 said:
Thank you. Looks like I need to switch back to more street friendly parts.
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Yes, if you don’t want to put boosters in that carb and recalibrate it, get a manifold on there with some heat in it.

Then it’s pretty easy to get the carb tune in shape.
 
I have a 750DP on an AG on my 360, with a 230* cam, and alloy heads. I drive from early May to Mid October. She burns 87E10 exclusively.
No problems of any kind.
Now, I am in no wise contradicting what Rat said; I just think it's a lil early to begin down that road.
 
tinman2 said:
That seems like a lot though.
Am I right or wrong about oil to rockers through block and head through head gasket? I thought I read that somewhere.
Didn't Magnums switch to oiling through pushrods?
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Wrong. either bad PCV system, bad valve guides and/or seals, or rings/worn cylinder.
 
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AJ/FormS said:
Ima thinking that if it was a bad PCV, all cylinders would be equally wet.
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Depends how it's routed, which is why I asked about pics, but the valve covers were already off.
If there's a bunch of excess hose ran high, and it's routed into the manifold rather than carb base, or something "custom" then possibly. Or it could be routed into the back of the plenum which just happens to drain into #3... Plus, it's probably the easiest and cheapest to rule out.

Sadly, it seems more likely the issue is deeper, but sometimes those things are tougher to determine without a teardown.

Broken rings came up, and that also seems like a reasonable suspicion. Hopefully not the case, but a compression test will tell a lot and I think I read it's planned to happen too.

Hope for the best with OPs folks. No car is more important than time with family.
 
Quick story about family. I was active duty Air Force. My dad was 81 and went into the hospital. I was in Arkansas, he in Pennsylvania. I put in and was approved for leave. I called and talked with him and he said he was "doing fine" so I canceled my leave. A few days later he passed.

I vowed that would not happen again so 11 years later when I could tell my mom was heading down hill, I closed a business I had and found a job close to her. Not in the same state but much closer. I visited often. Well, 2.5 years later the company closed all retail operations, but kept managers on for three months to "close up shop". During the second month, mom went into the hospital and the doctor said it wouldn't be long. So I moved into her house and visited every day for 5 weeks until she passed.

I still kick myself for not going to see dad, but I learned a valuable lesson.
 
Phreakish said:
Depends how it's routed, which is why I asked about pics, but the valve covers were already off.
If there's a bunch of excess hose ran high, and it's routed into the manifold rather than carb base, or something "custom" then possibly. Or it could be routed into the back of the plenum which just happens to drain into #3... Plus, it's probably the easiest and cheapest to rule out.

Sadly, it seems more likely the issue is deeper, but sometimes those things are tougher to determine without a teardown.

Broken rings came up, and that also seems like a reasonable suspicion. Hopefully not the case, but a compression test will tell a lot and I think I read it's planned to happen too.

Hope for the best with OPs folks. No car is more important than time with family.
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PCV has just enough hose to plug in rear base of carb. Last night, I stuck my compression gauge in #3 and turned engine by hand. I know that's not the way to check but I just wondered if I could get anything. After the intake valve closed, there was a whoosh of air sounding like it was coming back up the intake. Then I repeated with #1... no whoosh noise. So I plan to go ahead and remove intake and at least that one head, probably both. But with family issues, I'm not sure when I'll get to it. But I will update when I find something. Thanks again to all, Carl
 
Inspect the intake gasket carefully when removing the intake manifold, I worked on my friends car, and his brand new manifold was not straight. Was sucking oil from the cam valley
 
AJ/FormS said:
There is a port at the front of the carb for the PCV
I never recommend running the PCV to the Brake-booster port. When you do, it just creates problems, especially on a dual-plane.
bin there, dun that.
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Plugs did look like #5 and #8 were about right while all the others look way rich. And those two feed from right rear of carb. Could it cause that?
 
it very well could.
Blow-by should be entering at the front under the throttle blades. There is a splitter passage there that dumps it into both sides of the Two-plane intake, and it gets enriched by the fuel coming from the Idle and transfer circuits. Those blow-by gasses are NOT all combustion gasses especially not at idle. At idle they are mostly atmospheric gasses, so IDK, 21% oxygen . So when the system is hooked up right, it's gonna lean out the primary fuel.
But when you stick it on the booster port, that gets sucked into the back 4 cylinders, which are 5,7,6,&8 and they go lean. This is a hard tune, because the front 4 are rich, and the back 4 are lean; so I just never do it.
However, IMO, this should have nothing to do with the oil-washed piston top. Have you done a compression test yet? My guess is that the fire-ring blew out and now oil is coming in thru the hole. That happened to me once. Compression test found it rightaway.
 
AJ/FormS said:
However, IMO, this should have nothing to do with the oil-washed piston top. Have you done a compression test yet? My guess is that the fire-ring blew out and now oil is coming in thru the hole. That happened to me once. Compression test found it rightaway.
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What is the fire-ring and oil coming through what hole? Head gasket?

I have not done a proper compression test yet but all plugs are out and I did connect the gauge to #3 and turn the engine over by hand. I was just curious if I the gauge would even move. After the intake vavle closed, air was blowing out on the compression stroke. I couldn't tell if it was coming back up the intake port (bad valve or seat?) or if I was hearing it through the oil drain area of the head ( head gasket maybe?). I connected gauge to #1 and I could get the gauge to move and there was no air leaking sound.

I have been a my parents cleaning and taking care of them. My Dad would have fallen getting out of the shower if I hadn't caught him.
 
tinman2 said:
What is the fire-ring and oil coming through what hole? Head gasket?
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the fire-ring is the specific metal ring incorporated into the headgsasket, whose purpose is to keep the pressures created in the combustion chamber from escaping.
Sometimes the pressure can get so high that the fire ring gets slowly nudged towards the most weakest direction. Eventually it breakes and blows out often towards the valley . This leaves a direct path from the chamber to the valley. When running, the valley is chock full of oil in motion, and some of it is airborn. It is then easier for the piston on the intake stroke, to pull in air from there especially with the throttle closed or nearly so. Of course with the torn fire ring, that cylinder will then blow it all back on the compression stroke, the engine idles rough, and loses a bunch of power.
 
tinman2 said:
Yes. That's what I'm afraid off. If it's a possibility. This car has AC. I hate to mess with all that. Even just to pull the intake.
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Give that #3 a good compression Test to see if that head gasket is leaking. That is a lot of oil to have sitting on just one cylinder.

#3 cylinder Is right there at the oil feed from the block to the head.

Even with a bad value guide the engine usually burns the oil instead of puddling on the piston.

You would think there would be some oil getting into the cooling system also if the head gasket is letting it by in that area.

20230211_163041.jpg

'76 360 ^
 
George Jets said:
Give that #3 a good compression Test to see if that head gasket is leaking. That is a lot of oil to have sitting on just one cylinder.

#3 cylinder Is right there at the oil feed from the block to the head.

Even with a bad value guide the engine usually burns the oil instead of puddling on the piston.

You would think there would be some oil getting into the cooling system also if the head gasket is letting it by in that area.

View attachment 1716048260
'76 360 ^
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There is definitly a leak that I can hear just turning the engine by hand. I plan to pull the head as soon as my parents don't need my constant attention. Thanks for the picture. The oil passage to the head is what I have wondered about. The oil and the coolant don't seem to be mixing either way as far as I can tell so far, but some coolant may be disappearing. My brother in law, a long distance truck driver, had just bought the car a week before he dropped it off to me to check and straighten up a few things. When he bought the car from my neighbor, I drove it about 15 miles to his home and temp stayed about 190°. But when he drove it back, he said the temp would get about 210° before dropping back. I replaced a bad radiator cap and added exactly 1 gallon of coolant to put it close to full. The coolant recovery tank had 2 quarts of coolant in it.

I just bought a tech book about rebuilding the small block mopar. On the cover it lists everything from 273 through 360 LA and the Magnum engines. Then the example all the way through the book details a Magnum from a Dodge Dakota. No help there.
 
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Sounds like you have a plan, check out a few things and do what you need to do. When you have time.

Might have got hot and blew a weak spot in a head gasket?

So yeah take care of family, car is gonna be there. And Oh yes the mopars are good investments, they hold their value. A few parts and learning and tinkering, good to go.

Hard to say who had been in that engine before you got it. Improper torque on head gaskets, not enough torque. Maybe they cleaned up the deck (and or head) with a wire wheel on a drill and unknowingly cut a groove from that oil feed to the cylinder, then put on some cheep head gasket that leaks.

You never know with these cars having been through many hands.

Good Luck

☆☆☆☆☆
 
I recently read about a dyno test that didn't go well. Nick's Garage.

Blown head gasket. Oil feed. It gets smoky at 32:30, bad gasket at 48:30.



You can't say you're so special as to be the only one! Not any comfort in that I'm sure.

I never did find anything to read about the 'fix' or what was wrong. A deck problem, head problem, gasket problem, torquing the head with an impact wrench...I don't know.
 
George Jets said:
Give that #3 a good compression Test to see if that head gasket is leaking. That is a lot of oil to have sitting on just one cylinder.

#3 cylinder Is right there at the oil feed from the block to the head.

Even with a bad value guide the engine usually burns the oil instead of puddling on the piston.

You would think there would be some oil getting into the cooling system also if the head gasket is letting it by in that area.

View attachment 1716048260
'76 360 ^
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I always love your artwork! Nice job! lol
 
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