Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert! (2 Viewers)
- Thread starter 2001LC
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- Thread starter
- #302
Debris! During drilling & tapping.
This is proper procedure and how it should always be done. Although I disagree with blowing out cylinder with air. Which will more likely force practicals between piston and cylinder, than out the plug hole. If a guy is good and takes his time. Which is still Russian roulette, perhaps with only one bullet in the cylinder.
Not following procedure, is a fully load gun. Cylinder DEAD for sure.
This was my thinking also. Get in there and vacuum "every" practical out. This is what I do with intake ports, every time I pull the intake manifold.
Point of spark plug alert, is to avoid head damage. Those now faced with a Timesert, get the point!
awesomeissquid
SILVER Star
To add, I think my recent engine loss due to timesert debris being left in the cylinder should be warning enough that doing a timesert is very risky. If I had to do it in the future, I would only consider pulling the head.
In my case the previous owner had a timesert installed 3-5yrs prior to my purchase. When I replaced the plugs as part of my PM I found the debris and removed it (used a shop vac and a hose down the cylinder). The engine lasted another 2 years before the piston suffered a sudden unplanned partial deconstruction event. Would not recommend.
- Thread starter
- #304
Yeah, I agree.
I suppose if one really takes their time, takes every precaution, scopes and vacuums. Perhaps they'll not kill their engine. But in most cases, a time-sert is just a cheap temp alternative, while hunting for a good used engine. But if one's has a good lower end (cylinders), it's a waste of a good engine 98 of 100 times. "Russian roulette."
If one has a good lower end (compression) that they care about. Pulling head(s) and re-building or replacing head is best.
Here's yet another 4.7L with plugs walking out, I found yesterday: "I've lost count of how many loose plugs I've found"
I R&R a set of plugs, from an 03 w/315K miles on it yesterday. Since I could hear cold start tick, I was anxious to get is done. Which "tick" was either plug(s) walking-out (likely) or exhaust leak (not likely on 03-up).
I found 3 loose, 5 others with degrees of only snug. Bk 2 plugs 2, 4. & 6 loose, with 4 & 6 loosest and blowing gunk passed the threads. Actual all plugs were allowing some gases pass the threads, with #1 the least.
#'s 4 & 6 cylinders are the ones I find the loosest most times. Likely this is due to the air pipe/box covering head cover, holding in more heat.
#6 coil badly cooked from combustion gases. This is a sign #6 was no longer snugging up when at operating temp. It at this point, condition become critical. It would have been much longer until plug blow of, and damaged head. BK 2 coils also had the most visible heat damage, from heat expansion (swelling). They swelling causes case of coil to crack/split open. Excessive heat reduce life of coils, and leading cause of coil failure.
Gap on plugs were <1.2mm (limit 1.2mm). OLD NGK BKR6EGP
Bottom line; a 4.7L properly PM'd can last forever. The million mile Toyota was a VVT 4.7L. It's engine was disassembled and found to be in perfect condition. Even hone marks still in cylinders. It was maintained at one Toyota Dealership (a good one) never missing one PM interval. Granted, it was 1M in 5 years of mostly HWY driving, the best for engines.
Which PM, is more than just making sure spark plugs aren't walking out.
- Oil & filter.
- Air filtration. < < < (see alert)
- Air filtration, which includes no vacuum leaks (sucking in dust)
- Keeping coolant system properly maintained. (Don't over heat) Which includes clean radiator fins often. < < < (see alert)
- Blowing off dust & sand from around coils, before removing coils & plugs.
- R&R plugs and along with coil boots & top seals. Every 90K or soon, sooner if more than normal cold starts.
- Cleaning heads between intake manifold and heads, before pulling off intake manifold. Being supper diligent cleaning/vacuuming out every spec of dust from intake ports, before assemble.
- For those with VVT a special alert and modification. < < < ( see Alert)
Thanks for all the wisdom on this forum. Yes it's a basic concept but a lot of smaller details are overlooked. Take your time to do it right and the 2UZ will thank you.
I just replaced all of my plugs and original coils with Denso along with MAF and TB cleaning. I do keep up with this often, spark plugs were last changed 50k miles ago, so it was pretty buttery smooth.
I cut back and fixed a few vac lines that were getting brittle. IT will be cool to see if this has any effect on MPG but then again it's all about SPG's (smiles per gallon)
I was bummed to see I am taking on some oil again in the spark plug tube well. I replaced those seals about 20k miles ago. It's not submerged in oil like it was when I first discovered it, but I was bummed to see it either way. Maybe I'll replace the seal again or maybe just inspect it in 10k and ride out.
The original coils were in working order and it took a while for me to decide to replace something that wasn't broken but it will be worth it in the long run.
I just replaced all of my plugs and original coils with Denso along with MAF and TB cleaning. I do keep up with this often, spark plugs were last changed 50k miles ago, so it was pretty buttery smooth.
I cut back and fixed a few vac lines that were getting brittle. IT will be cool to see if this has any effect on MPG but then again it's all about SPG's (smiles per gallon)
I was bummed to see I am taking on some oil again in the spark plug tube well. I replaced those seals about 20k miles ago. It's not submerged in oil like it was when I first discovered it, but I was bummed to see it either way. Maybe I'll replace the seal again or maybe just inspect it in 10k and ride out.
The original coils were in working order and it took a while for me to decide to replace something that wasn't broken but it will be worth it in the long run.
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Just an update after running through two tanks of fuel after replacing coils, plugs, cleaning MAF and TB. The engine idles a lot smoother but no increase in MPG. Running a steady 12mpg.
- Thread starter
- #307
Spark plug blowing out. Is happen more and more as fleet ages. Which is so preventable.
I've never even suggested one of my threads or post, be in the sticky. But perhaps this one should. I hate seeing the 4.7L damged so needless.
I've never even suggested one of my threads or post, be in the sticky. But perhaps this one should. I hate seeing the 4.7L damged so needless.
What torque are you checking plugs at when verifying they’re tight? I’ve developed a cold engine tick that is only audible under light load and for a minute or so after start. I believe it is exhaust as I did plugs 8,000miles ago and checked torque 8 months and 1,000miles ago……all were good.
94SRUNNER
GOLD Star
I am checking every ~6 months and torque to 17ft-lbs.
Are you finding them loose at 6 months with torquing to 17ft/lbs? I haven't checked mine since torquing to 18ft/lbs 2 years ago. I plan to check this spring as soon as I can get the time.
Considering where I live, plenty of COLD starts. Although, 99.999% of them result in the engine getting to full operating temp.
Looking at my records, it's been 3 years and 50k miles. I'm pretty confident that they're all still tight, but plan to check asap...- Thread starter
- #313
That should be a good indicator as is ~16,000 miles a year.Considering where I live, plenty of COLD starts. Although, 99.999% of them result in the engine getting to full operating temp.
Which mile per yr, along with where you live. Indicates a good amount of HWY time. So I'd guess about ~2,100 cold starts. My bet is their snug. I shoot for timing replacement of spark plugs, with timing belt services (each 90K)
To be clear. My thinking is not so much if engine operating temperature reached each time started. But the heat expansion and cold contraction of the dissimilar metals (aluminium heads with steal spark plug). That each heat cycle of engine warm up than full cool down, expansion and contraction. Basically turns the spark plugs walking them out (un-threading).
Say one could drive 90K miles non stop, just after installing new spark plugs. They'd not have walked-out at all.
Best clue is sound cold engine TICK TICK TICK or some call it POP POP POP, just like exhaust manifold leak.
Can you hear the tick at idle?
- Thread starter
- #315
Yes. Sound just like and often confused with exhaust leak. If continues after warm up, once engine operating temperature reached. Is when action is needed to correct either, without delay. More so if tick is from spark plugs. Spark plugs are the easier one to correct. So I'd start there.
That's what I'm thinking. Another potential variable in all of this(which may have been covered) could be torque wrench calibration and also the difference between the consistency of digital wrenches versus the click style versus the bend style. A guy I worked with a lot when I was building a high performance car told me of how inconsistent click style wrenches are compared to digital. He said he did a bunch of tests to determine this and that the variance was enough to create a situation like this. The car we were talking about was an Audi 5 cylinder that had the same problem with plugs walking out over time. The spec on those is 22 ft/lbs. I used 25 ft/lbs on that car because it was heavily boosted and saw 7500 rpms plenty. Take that with a grain of salt, but I do trust this guy when it comes to stuff like that. Big YMMV on that one. I use my digital torque wrench for more sensitive stuff like spark plugs, head gaskets, etc.
94SRUNNER
GOLD Star
No. They are still in spec.
- Thread starter
- #318
I agree. I just picked up 2 more digital torque wrenches 1/4" Snapon & a 1/2 Matco. I've a HF 3/8 digital, but looking to upgrade that, with one reads out high torque hit. I'm going away for click type altogether.
What I've notice is as I slowly torque down, watching read out. At ~ 17ft-lbf feels like bottoming than slips, then torque reading drops back. I keep CW torquing past 17 a second time to 18ft-lbf, it again feels if bottoming without the slip. The slip is crush washer collapsing fully, so only felt with new spark plug..
We can install plugs without a toque wrench, old school. Sung than 1/4 to 1/2 turn more.
Notes:
We can be reasonably sure factory hit 13ft-lbf dead on -+2%. They walk out!
But we don't know at this point, if torque to 17, 18 , 19fl-lbf or more. Stops or even slows the walking-out, or if, by how much.
Follow-up: Helicoil completed by www.ctsoffroad.com. Joe has been a mechanic about 30 years. Good friend of our local Toyota 4x4 community. Joe also changed all my spark plugs while he was in there. So far so good. When I have to change the plugs in 120,000 I'll repot back if the helicoil held.
Follow up on Denso Iridium IK20TT plugs installed 50k ago:
All plugs were still torqued down to 18 ft/lbs using a digital torque wrench. I checked with ambient temps in the low 60's. I don't know how much that would even matter but figured I'd note it just because.
What I would like to know(and may be in this thread already but I didn't see it) is how many factory installed plugs(not dealer replacements) are walking out compared to replacements.
All plugs were still torqued down to 18 ft/lbs using a digital torque wrench. I checked with ambient temps in the low 60's. I don't know how much that would even matter but figured I'd note it just because.
At least from my above example, 50k might be a decent assumption at ~18 ft/lbs. YMMV. I'm going to check again in another 50k, or if I have to be in there for something else, whichever comes first.
What I would like to know(and may be in this thread already but I didn't see it) is how many factory installed plugs(not dealer replacements) are walking out compared to replacements.
