spark plugs.... Over thinking!

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SirRobyn0

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The non foulers came in a package of two. I assume I can just use one on the problem cylinder and leave the others as normal. Another thing to note I've had a long standing intermittent rough idle, it didn't do it after I replaced the set, and today I put 100 miles on and it was smooth idle, of course i cleaned that problem plug when i had it out, so I'm betting it's that plug that's fouling. Anyhow this is what I got and I have a new set of CR43TS so I'll get those installed tomorrow assuming it doesn't continue to rain like crazy.
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SirRobyn0

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Done this morning. Installed 8 of the CR43TS, and one of the non-fouler things into cylinder #7. This is what I found when I pulled the NGK's out. Keep in mind these are closer to AC Delco 44 or 45 heat range than the 43's the truck calls for.

Below picture: Note #7 is covered in oil deposits after only 300 miles, it did not totally foul out totally but you can see the deposits. #5 has a small amount of deposits and the rest are pretty white, not to bad but I think just a little hotter than she needs.

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Below: From left to right, #7, 5, 3, 1
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Below left: 4 of the 8 plugs about to go in. Below right: looking on both side of the down pipe plug #7 is the one on the right of the down pipe with the anti-fouler and plug installed, you can see it sticks out a little further but the plug wire is still safely away from the manifold.
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I don't know yet if I'll drive the truck tomorrow and I will let ya'll know if I can tell a difference in the way it runs, and of course after a few hundred miles I'll pull #7 and see how it looks.
 

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AuroraGirl

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Done this morning. Installed 8 of the CR43TS, and one of the non-fouler things into cylinder #7. This is what I found when I pulled the NGK's out. Keep in mind these are closer to AC Delco 44 or 45 heat range than the 43's the truck calls for.

Below picture: Note #7 is covered in oil deposits after only 300 miles, it did not totally foul out totally but you can see the deposits. #5 has a small amount of deposits and the rest are pretty white, not to bad but I think just a little hotter than she needs.

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Below: From left to right, #7, 5, 3, 1
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Below left: 4 of the 8 plugs about to go in. Below right: looking on both side of the down pipe plug #7 is the one on the right of the down pipe with the anti-fouler and plug installed, you can see it sticks out a little further but the plug wire is still safely away from the manifold.
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I don't know yet if I'll drive the truck tomorrow and I will let ya'll know if I can tell a difference in the way it runs, and of course after a few hundred miles I'll pull #7 and see how it looks.
im not expert but cheap manifold wrap where possible to try and hold heat there a bit longer may help get up to temp/keep deposits off too but it will only do so much esp since you have the little air tube thingy blocking most of it . how does that cylinders tab under the cap look?may be worth looking under valve cover for quick peek at that spot too, see if anything looks or behaves off
 

SirRobyn0

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im not expert but cheap manifold wrap where possible to try and hold heat there a bit longer may help get up to temp/keep deposits off too but it will only do so much esp since you have the little air tube thingy blocking most of it . how does that cylinders tab under the cap look?may be worth looking under valve cover for quick peek at that spot too, see if anything looks or behaves off
Well, it's a high mileage 305 and as you'd expect I do get a puff of blue at start up. The deposits on the plug are most definitely oil, based on that I assume a one or both of the valve stem seals on #7 are bad. I don't really like the idea of holding heat in, though I understand what you are saying and the reasoning.

Remember the ESC thread? Someone posting in that reminded me that I'm running around with my vac advance disconnected, because my ESC system won't retard the timing anymore and it'll ping like crazy under light throttle, if I hook up the vac advance. Sometime last year I bought regular HEI distributor so soon, sometime in the next week or so I'll be installing that so I can have a working vac advance that isn't so much it causes ping. My point is that I'll be pulling out the distributor soon, and the new unit comes with a new cap and rotor. The one currently on it has about 8K only.

I had the valve covers off a while back, I think last summer you might remember the thread where I bought a nice spendy set of gaskets and ended up having to use right stuff on both sides of the gasket to get them to seal up. Anyhow I did look at the drain back passages in the heads while I had them off and they were fine.

I know I could go in and replace the seals for #7 without pulling the head, but IDK I just don't really feel like it. I drove the truck today with the non-fouler thing installed and well, I'm not impressed with the idle quality. It's fine when I'm going down the road or even on a acceleration, but at idle it has.... I wouldn't quite call it a miss, but I'd call it an mild unevenness, I'll give it a few days and then see how I feel about it. I would image with that plug spaced out of the cylinder it just makes it a little less efficient. I could try going up another few steps in heat range, and that's probably what I'd try next if I decide the unevenness at idle of non-fouler is unacceptable.
 

SirRobyn0

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IDK, I'm not really thrilled with the non-fouler so far. I've not pulled the plug to see if it's doing it's job or not, but there is a noticeable unevenness at idle. I'm think it's that cylinder because the plug is pulled back some. I have a couple of R45TS on hand and I may pull the non-fouler out and stick one of those slightly hotter ACDelco plugs in and see how that works out. I know some of you are also in the ESC thread of mine, and in the back of my head I do wonder if having a properly working ESC & EGR which would enable me to have a properly working ignition advance, I wonder if that plug would be better able to clean itself then. I guess we'll see I think I'm kind of doubting that though, but it would be nice.
 

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IDK, I'm not really thrilled with the non-fouler so far. I've not pulled the plug to see if it's doing it's job or not, but there is a noticeable unevenness at idle. I'm think it's that cylinder because the plug is pulled back some. I have a couple of R45TS on hand and I may pull the non-fouler out and stick one of those slightly hotter ACDelco plugs in and see how that works out. I know some of you are also in the ESC thread of mine, and in the back of my head I do wonder if having a properly working ESC & EGR which would enable me to have a properly working ignition advance, I wonder if that plug would be better able to clean itself then. I guess we'll see I think I'm kind of doubting that though, but it would be nice.
What’s you gap? Tbi engines in the 90s had good luck reducing plug gap but. I think they ran wider gaps than 80s hei anyway, so it probably wouldn’t apply
 

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I only remember running (personally) anti-foulers on a 250 six. With clean plugs and anti-foulers on two different cylinders, it ran as smooth as a sewing machine.
 

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What’s you gap? Tbi engines in the 90s had good luck reducing plug gap but. I think they ran wider gaps than 80s hei anyway, so it probably wouldn’t apply
Sticker on my radiator say .045" so that's what I'm running.
I only remember running (personally) anti-foulers on a 250 six. With clean plugs and anti-foulers on two different cylinders, it ran as smooth as a sewing machine.
Ok, good to know. That might mean that the anti-fouler is not the cause. I will mention that 305 & 250 have a different angle that the plug goes into the block, not sure if that would matter. What I have noticed is after I changed the plugs after the initial foul out it was smooth as a sewing machine, for a while, and then smooth again after I cleaned the NGK's but that could be coincidental. Not sure if your following the ESC thread, but I have some issues going on in that department which might be the true cause. Really it's not bad, it's more about my anal retention of having a near perfectly smooth idle.
 

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I'm running NGK UR4's in mine right now, and they've been in there long enough now that I can't remember why I picked them over the ACDelco R45TS plugs I've always run before. The UR4 does seem to be on the hotter side, and the insulators are running pretty white on mine, but no issues with detonation (other than when my ESC computer gets cracked out and starts screwing with the timing for no good reason- it's on the docket for replacement when I get some extra money).

Other than #8 fuel fouling twice when I first got the truck in 2000, I've never had any issues. My 305 is starting to get tired now, and has quite a bit of blow-by (but oddly, the oil doesn't turn black that quickly); I only get a puff of smoke on startup once in awhile.

I drove my 1975 for many years and miles with an increasingly tired 350... It fouled #5 relentlessly, and #3 was pretty bad, too. Eventually ended up with anti-foulers on both cylinders, which helped a lot. I eventually switched from different flavors of Autolite plugs to ACDelcos, which seemed way more resistant to fouling... was even able to ditch the anti-fouler on #3, but not #5. I just replaced plugs piecemeal as they fouled... I think I ended up with an R46TS in cylinder 3, and just ran an R45TS in 5 and the rest of the engine. Towards the end of my having to rely on the '75 for daily transportation, #5 was getting really oily, and occasionally, the little hole in the anti-fouler would get clogged up with ash deposits and the cylinder would start misfiring and eventually drop- the plug would occasionally foul inside the anti-fouler, too. Still, experimenting with plugs and eventually resorting to those anti-fouler bodges bought me about 13 years and 60,000 more miles, and the engine ran surprisingly well...

It probably wouldn't make much sense to try and nurse an engine along that far anymore... The cost of oil would kill you (especially when combined with the cost of fuel) at today's prices. I was probably burning a quart every 50-100 miles, but was able to buy 5 quart jugs for $4.17 at Walfart back then.
 

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@Ellie Niner I am no where near that level of oil consumption. My oil consumption is surprisingly small I think that the issue what I am using is all headed to that one hole. FYI I read the other day that the R45TS was the original plug for the 305, but later was superseded to the CT43TS, because the slightly cooler plug tended to ping less. If you have read my ESC thread you know I'm having issues in that department too, so I don't wanna go up in heat range other than possibly on the one plug that's fouling.
 

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Years ago I had a beater S-10 that drank oil. It was so bad I had a buddy (he ran a custom vinyl decal shop) make a sticker that said “ I drive a hybrid, this truck burns gas AND oil”.

I tried the non foulers, the truck ALWAYS tan like crap with them installed. I removed them and just used a hole saw to cut a access hole in the wheel house to make plug changes easier. Of course it was plug number 6 that fouled, and the truck had A/C.

Have you done any diagnostic work to determine the engine health? If you have a cylinder hurt, I’m betting nothing you do will help. Possible valve guide or intake gasket leaking??

My only experience with the non foulers has been with my “hybrid” which wasn’t very positive. Maybe other have had better luck.
 

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Years ago I had a beater S-10 that drank oil. It was so bad I had a buddy (he ran a custom vinyl decal shop) make a sticker that said “ I drive a hybrid, this truck burns gas AND oil”.

I tried the non foulers, the truck ALWAYS tan like crap with them installed. I removed them and just used a hole saw to cut a access hole in the wheel house to make plug changes easier. Of course it was plug number 6 that fouled, and the truck had A/C.

Have you done any diagnostic work to determine the engine health? If you have a cylinder hurt, I’m betting nothing you do will help. Possible valve guide or intake gasket leaking??

My only experience with the non foulers has been with my “hybrid” which wasn’t very positive. Maybe other have had better luck.
As to your question about diagnostic, for oil fouling no not really. I did a compression 3 years ago when I got the truck and without looking in my maintenance book I can't give specifics but it was good at the time. With the mystery intermittent slight mis at idle, which I have been contributing to the oil fouling and anti-fouler I'm thinking another comp test is in order. This is not mentioned in this thread, but my ESC system is non-functional and I've been having pinging issues at timing settings that I think should not be a problem so there is that. Obviously the oil use could be contributing to this, but still it's another notch in the belt of issues and a comp test is in order I'm thinking.

I think, based on my observation that it's a valve guide, as I get a good puff of blue at start up but no other time. However I was thinking about this on my drive to the farm tonight after work. My truck has cat, and it is in good health. I've seen vehicles with cats, where the cat cleaned up the oil burning so much that you really didn't see it in the exhaust, but I don't go though much oil at all. I've never really kept track of it but not more than a couple quarts between changes so maybe a quart every 800 - 1,000 miles. I actually find it hard to believe I could be putting enough oil down one hole to foul it, but never the less it is. I've just been assuming it is mostly all making it out via the valve guides in that one cylinder.

I know this isn't said in this thread but my current #1 priority is getting the EGR passage in the intake unclogged. Then I should probably pull the plugs out as (again in the ESC thread but not here) I tried a standard HEI distributor for one day and swapped back to the ESC distributor due to severe pinging, which I'm sure was aggravated by the EGR situation. So I had one nasty ping fest on a hill with no where to pull off. I did the best I could to try to keep the ping down on that hill, but it was bad at one point and I had little choice but to keep going. So sadly I need to see if there is any signs of piston material on any of the plugs. So I may as well do a compression test at that time.

If all checks out relatively ok I'll take the anti-fouler out and run a hotter plug in that cylinder and see how it goes. But my fear is that my 305 is in worse shape than I thought. If that's the case I'll order a 350 from the guys in Spokane, and limp the 305 for the 1 - 3 months it may take to get my rebuilt motor. Honestly I'd really like a drop in a 350. Going from a 305 rated at 155HP 240TQ to a 350 with somewhere around 245HP 325TQ would sure be nice with the towing and hauling I do, but of course I do not want to put out the money.
 

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Sticker on my radiator say .045" so that's what I'm running.

Ok, good to know. That might mean that the anti-fouler is not the cause. I will mention that 305 & 250 have a different angle that the plug goes into the block, not sure if that would matter. What I have noticed is after I changed the plugs after the initial foul out it was smooth as a sewing machine, for a while, and then smooth again after I cleaned the NGK's but that could be coincidental. Not sure if your following the ESC thread, but I have some issues going on in that department which might be the true cause. Really it's not bad, it's more about my anal retention of having a near perfectly smooth idle.
Oh. well factory issues with chuggle and cruise ignition field fixed many issues by reducing to .035. This however getting egr is still important to be clear, but if you have each plug out for inspection and want to try it I’d like to hear how it goes
 

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after reading this thread Ive realized I dont know **** about spark plugs some serious plug science in here
 

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after reading this thread Ive realized I dont know **** about spark plugs some serious plug science in here
Fortunately its very simple if you keep it mostly or fully stock. Clean all plug-to-wire-to-tower interfaces, use a dielectric grease for ignition on them, dont drop spark plugs, stock gap + copper plugs usually work great, proper ignition timing and not burning oil are great ways to keep plugs clean , always ensure cap/coil/button/rotor are in good shape, use a spark plug socket to avoid breaking insulator, chase any threads if they are not clear, dont crossthread plugs, torque is a good idea especially if you arent a human torque wrench, Depending on plug/head you may need a dab of antiseize, spark plug wires shouldnt touch eachother or metal things, wire clips/guides are awesome, and if you go from a ribbed plug to a smooth plug you should replace the wire to avoid a carbon track. (Carbon tracks allow spark to ground on the outside of a plug, once there is evidence of this is cannot be repaired. plug and wire need replacement)
 

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