Engine charcoal and spark plug bonks

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Korys_thing

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Port Hueneme, CA
Pulled plugs in my 273 for the first time since I bought it, 7 hole plug gap was bent closed. New plugs in, drove it for a day and 7 hole plug gap is closed again (probably a dumb move).

Guessing the piston is the only thing closing that plug. Is there anything I can do without a full rebuild/keeping the engine in the car?

If it makes it any easier, I currently have the intake manifold off trying to solve some likely related issues. Valves and valley are full of carbon and something so thick I wouldn’t even call it sludge.

Pics attached just to share the…fun?

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is a rebuild in my immediate future?

*shakes magic 8 ball*

"it is decidedly so"
That sounds more like a reality check 8 ball. The magic one would tell me how great my future engine days are.

I guess it’s time to invest in a cherry picker and engine stand! The 16 year old neighbor kid that lives in my shared apartment garage is about to be so bummed when I’m in there all the time
 
That sounds more like a reality check 8 ball. The magic one would tell me how great my future engine days are.

I guess it’s time to invest in a cherry picker and engine stand! The 16 year old neighbor kid that lives in my shared apartment garage is about to be so bummed when I’m in there all the time
*cough*

5.2 magnum

*cough*
 
Quaker State strikes again! If you still have the old plugs you took out, take the washers off of about 4 of them and screw them onto the #7 plug to space it out a bit before you regap it and put it back. At least you can drive the car inside the garage after you yoink the kid out of there and toss his bed in the street!
 
*cough 5.2 magnum *cough *cough



Did someone already say that?
 
Sounds like yall need a throat lozenge…I have some old candied oil that might do the trick.

I guess pulling the engine would help me get at the rear main leak and the clogged up oil screen. Putting in something else might be the responsible thing to do. Right?! Maybe.

Don’t know what it would take to make the jump over to a 5.2 but sounds like it’s time to start looking at the conversion threads and find a crate engine.
 
i wouldn't put dime one into that 273.

5.2, rings/bearings as needed, reground cam, set of reman heads that it'll likely need, offshore dual plane intake. port all of your tins over and you're set.
 

Quaker State strikes again! If you still have the old plugs you took out, take the washers off of about 4 of them and screw them onto the #7 plug to space it out a bit before you regap it and put it back. At least you can drive the car inside the garage after you yoink the kid out of there and toss his bed in the street!
Or Pennzoil
 
all the plug threads look to have been protruding into the combustion chambers past the threads in the head. the first few threads look to be covered in carbon to corroborate that too.
i'd get shorter reach plugs (shorter thread wise). the plug tips shouldn't get anywhere the pistons..... ever. too long a plug seems to me the only way they can do that.
neil.
 
all the plug threads look to have been protruding into the combustion chambers past the threads in the head. the first few threads look to be covered in carbon to corroborate that too.
i'd get shorter reach plugs (shorter thread wise). the plug tips shouldn't get anywhere the pistons..... ever. too long a plug seems to me the only way they can do that.
neil.
RN14YC plugs are correct for a 2 barrel 273. If there is something smashing the ground electrode, there is an issue in the cylinder and not a plug length problem. Messing with plug length screws with heat ranges which can cause other issues.
 
Wow, that's pretty gunked up!
Thanks for sharing the image though.
I suspect if #7 electrode is getting hit, it is probably hitting something harder than carbon. Thinking your about to have catastrophic failure in #7 from an extremely worn crank of rod bearing.
Do 273 pistons tend to he down in the hole, zero, or above deck?
Anyway, watching to see further teardown and to see which way you proceed with the building.
 
Wow, that's pretty gunked up!
Thanks for sharing the image though.
I suspect if #7 electrode is getting hit, it is probably hitting something harder than carbon. Thinking your about to have catastrophic failure in #7 from an extremely worn crank of rod bearing.
Do 273 pistons tend to he down in the hole, zero, or above deck?
Anyway, watching to see further teardown and to see which way you proceed with the building.
The 2 barrel engines are just below deck. The 4 barrel engines have domes above the deck. No pics so we don't know which engine he has.

He might as well pull the heads from here. Or just pull the engine. It's going to need a good cleaning and gone through or a replacement.
 
Yeowza!!!!
I haven’t seen one like that in ages.

I’m guessing that one wasn’t subjected to a strict 3000 mile oil change regimen.
 
we going old skool. fill it with diesel and a few quarts of ATF, let that bad boy idle for 'bout half an hour. that'll sort it right on out.

I did that about 40 years ago to a 350sbc in a 70 impala I bought for $100.
The oil light would come on at idle when it was hot.
That and a swirling blue cloud following you everywhere.

After the doooshing, and a couple of oil changes, it was fine.
I drove it for a few years and then ended up selling it for $500.
 
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