Author Topic: oil fouled  (Read 5793 times)

Offline markzepp820

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oil fouled
« on: March 31, 2007, 11:39:00 pm »
I have a 79' chevy truck with a 350 thats been recently cutting out. So I pulled the spark plugs and 4 out of 8 were oil fouled. What could be the problem(s) to half my plugs getting oil-fouled?
thanks in advance,
Mark
 


Offline 123 pugsy

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Re: oil fouled
« Reply #1 on: April 01, 2007, 06:52:00 am »
Were they all from the same side?

Pugsy
76 C10 LWB
TPI 350

Offline joesgarage71

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Re: oil fouled
« Reply #2 on: April 01, 2007, 07:36:00 am »
I take it she gots high miles. Its getting worn out, time to rebuild, you might go a step or two hotter on the plugs to help it burn the oil off.
Steve

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14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt

Offline Lt.Del

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Re: oil fouled
« Reply #3 on: April 01, 2007, 11:08:00 am »
Hey Mark, Joesgarage is right.  Get a hotter plug.  

If rebuilding the engine or getting a new crate engine is out of the picture right now, or, even something as relatively inexpensive as rebuilding the cylinder heads to replace the oil seals and guides, you can use a hotter plug to burn off that oil on the plugs.

Before putting in my 383 stroker, my 350 had over 160,000 miles and I had to use hotter plugs due to it missing on the 8th cylinder.

They worked awesome!  The ones I originally used was

Champion RV17YC However, for a hotter plug, the great one is Champion 4113 Truck plug...they are all black.  Go to NAPA and ask for these.  They may have to order them but for an engine like yours, they are well worth it.

The hotter 4113 is on the right....

 

SgtDel
aka "Andy"

www.delbridge.net

1979 Big 10 383 stroker
1991 Blu 'Burb 3/4 ton 4x4

Edited by: SgtDel  at: 4/1/07 10:38 am

Offline markzepp820

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oil fouled
« Reply #4 on: April 01, 2007, 10:53:00 pm »
thanks for the info. My 350 does have alot of miles on it(187,000). Everything else besides the motor is in good shape. In the near future, I want to by another 350 for it. But I will try those hotter plugs you all talked about, until then. Also, how do hotter plugs work?

             thanks,
                       mark


Offline SUX2BU99

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Re: oil fouled
« Reply #5 on: April 03, 2007, 02:15:00 pm »
I believe it has to do with the length of the insulator, which is that little snout above the electrode. See how much shorter it is than the colder plug on left? I'm forgetting the reasons for it, but I think the insulator length of the plug is affected by the temperature of the combustion chamber when the plug fires. Hotter plugs can cause knocking though. In engines that have a tendancy to knock, colder plugs can be used.

85 Chevy Silverado C10 short, wide, yellow, 2wd. Lowered, 60-over 350 with Dart Iron Eagle heads and Comp Cams XE268 cam, TH350 w/ shift kit, 3.40 Gov-lok 12 bolt.

Offline VileZambonie

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Re: oil fouled
« Reply #6 on: April 03, 2007, 07:27:00 pm »
Yes you are correct it is the surface area of the insulator on the combustion chamber side that determines the spark plug heat range.

How often do your plugs foul? Before you run a hotter plug you might want to consider the side effects. If you drive this truck on the highway or pull heavy loads then absolutey do NOT run a hotter plug.

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Offline markzepp820

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Re: oil fouled
« Reply #7 on: April 04, 2007, 12:56:00 am »
the plugs are starting to foul more sooner now. I do alot of stop and go driving.  
                                mark