Got a couple of white plugs.... - Chevelle Tech
 
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post #1 of 14 (permalink) Old May 6th, 20, 5:09 PM Thread Starter
 
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Got a couple of white plugs....

396
Holley 3310-3
weiand dual plane
plugs are NGK GR4 so (R45 equivalent)

I have a couple of white plugs, number 5 and 8.

Any ideas?

Thanks,
D
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Darren Trudeau is offline  
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post #2 of 14 (permalink) Old May 6th, 20, 5:39 PM
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Rame
 
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Re: Got a couple of white plugs....

No fire or coolant leak. Running bad? Smoke on start up?

.
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post #3 of 14 (permalink) Old May 6th, 20, 7:13 PM
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Re: Got a couple of white plugs....

Those two are the only ones that actually look close to right. The rest are way rich.
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post #4 of 14 (permalink) Old May 7th, 20, 12:28 AM Thread Starter
 
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Re: Got a couple of white plugs....

Quote:
Originally Posted by sampoerna415 View Post
No fire or coolant leak. Running bad? Smoke on start up?
The coolant is not going down in the rad, feels fine like it's hitting on all 8, I haven't looked for white smoke on start up but think probably won't smoke as the coolant is staying at same level in rad.
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post #5 of 14 (permalink) Old May 7th, 20, 12:34 AM Thread Starter
 
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Re: Got a couple of white plugs....

Quote:
Originally Posted by Dave Ray View Post
Those two are the only ones that actually look close to right. The rest are way rich.
I agree the other 6 are reading too rich and a drop in main jets will be on the short list but the amount of difference there is the two white ones might be scary if the other 6 were right.

Still have to figure out why 2 are white first.

But for when/if it's figured for later,

6.5 power valve and 70 jets now, go to 68's and 8.5-9.5 power valve?
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post #6 of 14 (permalink) Old May 7th, 20, 7:31 PM
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Re: Got a couple of white plugs....

So, what is the compression pressure by test for each cylinder, with the throttle full open?

What has been done to set the valves correctly? E-O, I-C method???

Remember, unless the intake manifold is an open single plenum, cylinders 2, 8, 3 and 5 all run off one side of the carb, 1, 7, 4, and 6 operate off the other side of the carb.
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post #7 of 14 (permalink) Old May 8th, 20, 2:43 PM Thread Starter
 
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Re: Got a couple of white plugs....

Ok Dave ,
I'll look at older compression results and probably do a new test soon.
Valves were done while running last time (loosen till clacking then tighten 1/2 turn.
If it is coolant would it most likely be exhaust guides?
Only other way to tell is pull heads I guess?
Thx,
D
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post #8 of 14 (permalink) Old May 8th, 20, 4:48 PM Thread Starter
 
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Re: Got a couple of white plugs....

Coolant entering combustion chamber shows on the plugs as rusty chunky buildup yes/no?
Also causes misfire after a while yes/no?
The coolant in rad should be going down also.
Vacuum leak somewhere maybe then at base gasket or throttle body affecting 5 and 8?....
D
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post #9 of 14 (permalink) Old May 12th, 20, 2:30 PM
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Re: Got a couple of white plugs....

How was the engine ran before you pulled the plugs? Were you just cruising around normally, or WOT, kill ignition, put in neutral, coast to stop and pull plugs?
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post #10 of 14 (permalink) Old May 12th, 20, 5:16 PM
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Re: Got a couple of white plugs....

If all settings are correct, spark plugs don't load up, or, or go lean as rpms change, those changes only occur in a parameter, or parameters that are not correct, changing running conditions as that rpm level changes.
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post #11 of 14 (permalink) Old May 12th, 20, 5:26 PM
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Re: Got a couple of white plugs....

Quote:
Originally Posted by Darren Trudeau View Post
Coolant entering combustion chamber shows on the plugs as rusty chunky buildup yes/no?
Also causes misfire after a while yes/no?
The coolant in rad should be going down also.
Vacuum leak somewhere maybe then at base gasket or throttle body affecting 5 and 8?....
D
If it's just a drop of coolant every now and then it would be hard to notice the level going down, the easiest way to check for that would be to look at the pistons, they will be clean or at least cleaner than the others. It has the same effect as dripping water down the carb to clean the carbon out. This would be an unusual problem though, are you sure it's not ignition problems, or maybe something dumb like the wires are crossed? Don't take that as an insult, that stuff happens all the time. Maybe try a basic tune up, plugs, wires, cap, rotor, etc, and see what changes.

.
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post #12 of 14 (permalink) Old May 17th, 20, 10:57 AM Thread Starter
 
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Re: Got a couple of white plugs....

My diff had what I thought was a leaking pinion seal and it's ballooned to a bigger situation so that's why I haven't been back to this plug issue.

The plugs were pulled after driving around regularly.

I have found a very small crack that is not completely through but does open up a bit when carb in snugged down in the throttle body of the 3310 on the right front corner behind bolt hole so that might be it.

Dave Ray will know the layout of the dual plane on there and make the call if he pops by again.

Thx,
D
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post #13 of 14 (permalink) Old May 17th, 20, 3:02 PM
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Re: Got a couple of white plugs....

2, 3, 5, 8 are one set, 1, 4, 6, 7 are the other set, or, "plane".
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post #14 of 14 (permalink) Old May 18th, 20, 9:09 AM
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Re: Got a couple of white plugs....

Put a pressure tester on your radiator and let it sit for a while with pressure to see if there is a water leak. If so the next question is WHERE??

Have you ever stopped to think and forgot to start again??
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