Thread: Dirty Spark Plug Cylinders
12-09-2009, 09:14 PM #1
Dirty Spark Plug Cylinders
I pulled my spark plugs today for the first time (at 75 hrs). 2 of them looked fairly good, but the middle plug was very fouled up. I can see little loose rust particles down at the bottom of the cylinder around the edges of the ring. Is this normal? Should I attempt to somehow clean the cylinders and the "plug boots"? If so, with what? I don't know much about engines so I'm not sure how catastrophic it would be if any of these small particles fell further into the engine.
Also, should I be spraying bomb lube into the cylinders before installing the new plugs???
Thanks for any guidance!
12-09-2009, 09:52 PM #2
Keep the water from getting into the plug hole, that's what caused this to happen.
Best thing in any area like this is totally dry and clean.
When you replace the coils, make sure the seal actually fits correctly in the neck of the hole.
I use petroleum based gel thinly wiped in the edge, and on the seal lip too.
As you push the coil in slowly, rotate the coil, so it will allow the seal to slip into place in-between the coil and plug hole wall. Then just ease it in, til it stops against the top of the plug. One slight twist clock-wise, while pushing down-wards to orientate it to meet the coil plug, and it will snap in place perfectly.
Mind you only use a VERY small amount of vaso though... almost nothing is perfect.
Should stop this in future for you.
12-09-2009, 10:28 PM #3
<FONT face=Arial><FONT size=4><STRONG>To protect spark plug boots:
12-09-2009, 10:34 PM #4
use dielectric grease, thats what it is for.
you could screw a new spakplug in that hole, snug , but not cranked down.
then spray it wilth some penetrating oil,
then use a chopstick and a paper towel to wipe out the hole.
really not a good idea to let any crud fall into the cylinder.
then use some dielectric grease on a towel to mop up any bits, or compresed air to blow out the hole.
mine have all been clean every year, so make sure your boots are properly sealing the tops of the cylinders.
12-10-2009, 12:08 AM #5
Yep, that too.
Best thing is to keep anything out, and just seal the cap/coil.
Thing is that with grease(die-electric or not, dust or any other form of crap can get on/into this, and then the process of time it could track at high voltages over time. The thing is that these coils are high-energy ones, and maybe we would not notice, but a few Kv here and there lost over time may not be noticed, but will make a difference.
We strive to find higher energy to light the mix, but sometimes the OEM coils are just leaking, and could save the day.
I would err to the side of the following given the opinions.
Open coil out of hole, get the compressed air blown around in there... as you should ALWAYS do anyway, to blow any crud out. If you notice crud on the plug, first crack the thread open, then go for another blast of air in there.
ANOTHER favorite is to check the plug wrench is clean from crud too.., many a time can cause contamination without thinking.
Change the plugs, having cleaned the insulator well with clean dry soft tissue, and leave NO finger prints on them either, as these can cause HT leakage under the conditions in there too. I hold the ends of the plugs with point-pliers, and offer the plug gently to the threaded hole... it will sit in there without turning too.
Next CLEAN plug wrench... get the plug tightened as per... do not X the thread..!!, it should feel correct when all is good.
Make sure the nose of the coil is clean from that reddish dust you will see. This is conductive as well!!. I always work the rubber/silicone caps off the nose of the coil, and give them a good old clean with carbi-clean or prep-wash. Let them dry, do the same for the coil tip too. Clean the stem of the coil down too... we don't want tracking along here either, we just want all the energy to go in the plug, and across the gap to fire to mixture.
CLEANLINESS is the key. Next make sure you have cleaned the seal too if in doubt, then I always rub a touch of vaso in my fingertips, and rub around the seal part that will face-up to the side of the spark-plug hole.. with a touch around the neck of the hole, then put the coil back in, with the little magic twist as it seats firmly in place. It should have all seated nicely, and no contamination of ANY sort will be around the area where HT is discharged.
Oh, and by the way... MAKE SURE you don't loose the little red silicone seal that is in the coil connector... it is critical in this environment.
Always fires first shot, never hear a miss, nor stumble, and all is good.
To be honest I have not yet had any success better than cleanliness near HT on engines. VHT seala or anything else.
Air and clean is always good, and cleaning is easier than scraping of f the lashed on fluids and jollops in use today.
Good idea to Di-electric grease inside the connector though, it keeps water out, and connection for current good.
12-10-2009, 09:18 PM #6
12-11-2009, 06:33 AM #7
Spark plugs looks good. They look normal. Your 4tec engine is running happy and not overheating. Spark plugs can tell you a lot of things that goes inside your combustion chamber #2 spark plug boot is letting water in. Before you take the spark plug off, always inspect the spark plug and it's chamber. if it's dirty, use a vacuum cleaner to suck it out before you take the spark plug off. Chances are, there's more Vacuum cleaner in every household than a compressor
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