350 Problem

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82chevy350

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Engine Size
350, 350
My 76 has a 350 that is having some problems. I keep fouling number 8 spark plug it gets oily(wet). I got a set of 305 heads off a buddy that i put on the motor for torque. Anyway the truck smokes like its getting oil in the cylinder all other plugs burn dry light brown colored.I have yet to do a compression test.. I really wish i had the money to build a new motor or find a straight 6. Do you guys think this is from a bad pcv valve or just a worn valve guide?:nono:
 

sean1960

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Custom GMC
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454
Worn valve guide.
 

bucket

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Did the problem exist before the head swap?
 

Jason92

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k20
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350
I have a 86 silverado and the transmission vacuum line is attached to the intake manifold near the number 8 cylinder. Is yours like that? It could be a ruptered diaphram in the vacuum modulator and getting sucked in the intake and going to the cylinder(transmission fluid).
 

RetroC10Sport

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I have a 86 silverado and the transmission vacuum line is attached to the intake manifold near the number 8 cylinder. Is yours like that? It could be a ruptered diaphram in the vacuum modulator and getting sucked in the intake and going to the cylinder(transmission fluid).

I am inclined to go with this...I had a 1988 Buick that had a bad vacuum modulator and it would suck trans fluid up through the intake and smoke like a freight train.
 

82chevy350

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It was the modulator valve thanks guys
 

HotRodPC

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454 - Turbo 400 - 3.73
I have a 86 silverado and the transmission vacuum line is attached to the intake manifold near the number 8 cylinder. Is yours like that? It could be a ruptered diaphram in the vacuum modulator and getting sucked in the intake and going to the cylinder(transmission fluid).

I am inclined to go with this...I had a 1988 Buick that had a bad vacuum modulator and it would suck trans fluid up through the intake and smoke like a freight train.

It was the modulator valve thanks guys

Awesome **** guys. Gotta a 5 post Newbie helping out one of the site veterans !!! That's what makes this place so great. Thanks, and Welcome Aboard GMSB Jason !!!
I woudln't have suggested that. Back in the 70's when 305 came about they had a cooling problem back there on the right bank in the back of the block caused by the head casting. It was only for 2-3 years and the head was correted. I'd say those bad heads have all been recycled by now.
 

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