My buddy Roger has a 99 4runner w/ the 3.4L. It started running crappy so he brought it to a garage, they checked his plugs, charged him some money, and found out that all 4 electrodes on one of his Bosch Platiunum +4's had broken off inside the engine. They pulled it and replaced it. They said that he would have heard it if they had caused valve damage, they thought that the broken peices were burned up in the engine or blown out the exhaust. Neither of these things seem likely to me, I would assume they are still in there somewhere. Am I being over paranoid or are either of those two options likely?

They also said to never use anti-seize on your plugs, I have always used it, should I not?

 

anti-seize is fine... and dont use bosch plugs and you will be fine

 

I agree on the bosch plugs, however, he obviously did, it is too late to change that.

 

Hmmmm. Those four electrodes are already in the chamber and don't vaporize..... Aren't those supposed to last 100,000 miles.....

I hope that the parts went downstream quick!

Even if they would vaporize how deep are the scratches on the cylinder walls? I would get a magnet to see if some peices/parts would come out....

If they don't they would have gone downstream and are probably stuck in the cat.... If the engine is running fine now no valve damage may have occured... but I would still check with a magnet.....

And with my cast aluminum head and steel sparkplugs I use anti-seize everytime. Cuz once I didn't and it was a PITA!!!!! Now don't use too much... One of those little pouches is more than enough to all my plugs.... And don't do what a lawn mower repair place did to my riding mower, red loctite on the oil drain..... gggrrrrrrrrrr only broke one wrench.

 

:pat:




I second the magnet idea. FWIW, in 10+ years of working on my rigs, I've never used anti-seize on my plugs and have never had a problem.

 

When he mentioned the problem he was having to me I said that he should replace his plugs and wires, he said he just recently did, "I bought top of the line" he said, "Bosch platinum 4's!". All I could do was groan. I told him to check them anyway. Instead he went to a garage...oh well, his dime. The cylinder walls is what I was wondering about. Plus if they are jammed in there, how bad will it get before it becomes noticible, I hope they went down stream ASAP, but it seems like too much to hope for.

Not using antiseize is fine, but assuming you keep it off the electrodes and only put enough on to make a thin layer on the threads, is it BAD to use it? I didn't think it would matter, but when I was first shown how to change the plugs, I was told to put a little anti seize on them, just in case. If it is bad, I would stop, if it isn't bad then it seems like cheap preventative maintenance.

 

Anti-seize is just reassurance you aren't going to break a plug off when taking them out. It makes it more of a comfortable situation. I use it on all of mine and never had a problem with it.

 

That was my basic belief and experience too.

 

Quick spark plug question. Once you take a sparkplug out, do you have to replace it because of the weird washer it uses?

 

no...sometimes I take mine out and clean them with a wire brush and regap them

 

Another vote for anti-seize being fine, as long as it is used in a thin layer. I also like the magnet check idea - use one of those little ones on a flexible cable. NGK spark plugs are better (and cheaper) than Bosch. One could also check the cylinder walls w/a fiberoptic camera/light combo (some high-tech garages have the equipment to do this). It also wouldn't be a bad idea to remove the pipe in front of (or remove) the cat. convertor and inspect for debris, either visually or w/a magnet. This will ensure no future damage to the cat. or engine due to a plugged cat. Good luck!

 

save the bosch for your german cars. i like peoples thinking when they buy the bosch, they think because it has 4 electrodes it'll produce more spark? no! electricity arcs to the nearest conductor, so you'll still only get 1 spark, and spend 4 times as much to do so.

as for anti-sieze, you don't need too much of it, but it's definitely not going to hurt anything. the mechanic's reasoning is probably that since anti-sieze produces more clamping force on the threads it'll strip them out easier. just don't go overboard when tightening your plugs, and you should be fine.

 

I use a layer of synthetic oil on the plug threads instead of anti-seize, and have never had a problem getting a plug out.

 

One theory on anti-antisieze it that it can insulate the plug - the plug is grounded through the thread contact. It shouldn't, but using too much is bad. The other supposed issue is what Lyle said - easier to overtighten.

In 30+ years of vehicle maintenance, I've never used anything and never had a plug stick.

As for those electrodes, they should have blown right out. If they didn't get blown right out it's probably too late now... Here's a pic of a cylinder head that sufferred a bit from a broken ring. (I'm gonna make a little glass-topped table with of the pair of heads, it will be the most expensive piece of furniture I'll ever own...!) Maybe I should have used anti-sieze on the rings!

 

what kind of heads are those? look like something off an outboard motor.

 

Yep, good call! That *was* a 2 liter Merc 175hp. It's *now* a 2.4 liter Merc 240 hp. As a side benefit it went from a 65 mph boat to an 80 mph boat... But then again, WOT fuel consumption increased by a lot. I believe it has shower nozzles for jets...

 

"Hey man, nice boat... I swear to god it is...I'll say it right to your face."
[In my best 'Donny Baker' voice]

 

i've always wanted to see somebody put an OMC 3.7l 4 banger into a truck. it's literally half a ford 460, but it's got a chevy bolt pattern

myself, i've just got a little 13' smoker craft with a 15hp evinrude, but it scoots me to the fishing holes good enough. might save up for a jet sled for running the rivers, though.

 

My understanding is that aluminum heads can produce a galvanic response to the steel/iron sparkplugs which can produce a bond.. and thus seize.

There are different formulation of anti-seize compounds... some prefer the carbon based.

As to whether it works or not, I don't know. It would seem to me that a thin layer of grease/oil would work just as well.

 

i think im the only person who admits to having boschs (+2, never the +4) ive said before that at the next chage they will be NGK. ive gotten over 30k on them w/o issues (again prolly the only person) and still get ~20mpg.

i would look into why the tips broke in the first place.
contact bosch and tell them your expecting a new motor from them if an issue arises, after all they garaunte their performance.