as in blows out of the cylinder--- My neighbor has a Ford 250 (gas , but I don't know the engine), are these problems Ford only? Makes you wonder if they road tested any before production, or why they changed from the old sty;e plug????
what brands have the spark plug blows out problem?
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Originally Posted By: edwardh1
as in blows out of the cylinder--- My neighbor has a Ford 250 (gas , but I don't know the engine), are these problems Ford only? Makes you wonder if they road tested any before production, or why they changed from the old sty;e plug????
Not many diesels have a problem with spark plugs.
as in blows out of the cylinder--- My neighbor has a Ford 250 (gas , but I don't know the engine), are these problems Ford only? Makes you wonder if they road tested any before production, or why they changed from the old sty;e plug????
Not many diesels have a problem with spark plugs.
Ford modular engines, the 4.6 and 5.4 up until 2003-2004. Too few threads in the heads for the plugs and "improper" torquing of the plugs into the head. Not one of Ford's better ideas on an otherwise good engine.
Whimsey
Whimsey
wonder why they reduce the number of threads?
big savings Huh?
Like the GM dexcool change to Dexcool/plastic intake parts
big savings Huh?
Like the GM dexcool change to Dexcool/plastic intake parts
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Originally Posted By: edwardh1
wonder why they reduce the number of threads
Cheaper to machine.
wonder why they reduce the number of threads
Cheaper to machine.
Difficult to believe that a real engineer would have signed off on so few threads spark plug retention in a design.
Originally Posted By: HerrStig
Originally Posted By: edwardh1
wonder why they reduce the number of threads
Cheaper to machine.
..."a penny saved is a penny earned"....
s/o
Whimsey
Originally Posted By: edwardh1
wonder why they reduce the number of threads
Cheaper to machine.
..."a penny saved is a penny earned"....
Whimsey
Originally Posted By: Whimsey
Originally Posted By: HerrStig
Originally Posted By: edwardh1
wonder why they reduce the number of threads
Cheaper to machine.
..."a penny saved is a penny earned"....
s/o
Whimsey
Exactly. Sometimes the engineers who designed our engines don't always know what's best.
Originally Posted By: HerrStig
Originally Posted By: edwardh1
wonder why they reduce the number of threads
Cheaper to machine.
..."a penny saved is a penny earned"....
Whimsey
Exactly. Sometimes the engineers who designed our engines don't always know what's best.
Only the one type of 5.4 had real issues. The others had issues like spark plugs breaking off when removing them.
I dont recall which was which.. but one had the weird plugs that would snap off on removal(and sometimes loosen).
And the other 5.4 had the ejection issue with 3 threads holding them in.
I cant remember any 4.6 that had an ejected plug issue?
I dont recall which was which.. but one had the weird plugs that would snap off on removal(and sometimes loosen).
And the other 5.4 had the ejection issue with 3 threads holding them in.
I cant remember any 4.6 that had an ejected plug issue?
Originally Posted By: Whimsey
Ford modular engines, the 4.6 and 5.4 up until 2003-2004. Too few threads in the heads for the plugs and "improper" torquing of the plugs into the head. Not one of Ford's better ideas on an otherwise good engine.
Whimsey
Well the 3v engines had that pesky cam phaser issue as well.
Ford modular engines, the 4.6 and 5.4 up until 2003-2004. Too few threads in the heads for the plugs and "improper" torquing of the plugs into the head. Not one of Ford's better ideas on an otherwise good engine.
Whimsey
Well the 3v engines had that pesky cam phaser issue as well.
Originally Posted By: demarpaint
Originally Posted By: Whimsey
Originally Posted By: HerrStig
Originally Posted By: edwardh1
wonder why they reduce the number of threads
Cheaper to machine.
..."a penny saved is a penny earned"....
s/o
Whimsey
Exactly. Sometimes the engineers who designed our engines don't always know what's best.
I think probably the pressure from marketing to reduce cost forces engineer or purchasing dept to cut corner.
Originally Posted By: Whimsey
Originally Posted By: HerrStig
Originally Posted By: edwardh1
wonder why they reduce the number of threads
Cheaper to machine.
..."a penny saved is a penny earned"....
Whimsey
Exactly. Sometimes the engineers who designed our engines don't always know what's best.
I think probably the pressure from marketing to reduce cost forces engineer or purchasing dept to cut corner.
There are times when car makers are developing engines and drive trains that they have to modify one strategy to pay for another. Example: Optimizing combustion and injection to speed up catalyst warming times and cold starts for emissions. They might do that to reduce costs on the catalytic converter and emissions systems enough to offset some of the cost of direct injection.
If left to the engineers, you'd probably have a car that costs 10K more with minimal additional benefit versus something that's a unified whole in terms of production strategies. Then people on here might be bytching about how automakers "overengineer" their vehicles. Unfortunately, someone has to have a business sense when mass producing vehicles. It just becomes particularly unfortunate when you get things like the GM ignition situation or poorly thought through cost cutting.
If left to the engineers, you'd probably have a car that costs 10K more with minimal additional benefit versus something that's a unified whole in terms of production strategies. Then people on here might be bytching about how automakers "overengineer" their vehicles. Unfortunately, someone has to have a business sense when mass producing vehicles. It just becomes particularly unfortunate when you get things like the GM ignition situation or poorly thought through cost cutting.
Originally Posted By: Rand
Only the one type of 5.4 had real issues. The others had issues like spark plugs breaking off when removing them.
I dont recall which was which.. but one had the weird plugs that would snap off on removal(and sometimes loosen).
And the other 5.4 had the ejection issue with 3 threads holding them in.
I cant remember any 4.6 that had an ejected plug issue?
The spark plug launching started with the 4.6(common on Crown Vic, grand Marquis etc), soon progressed to the 5.4...
Issue isn't the amount of threads but not being torqued properly... Too little torque the plugs will likely loosen and start "shaking" wearing the threads away(this happened from factory)... Then you have the ham fisted that over torqued, which caused the threads to pull and again the plugs loosen wearing out the threads... Poof another plug launched...
Out of seven modulars I've never had a issue, but admitedly it's a [censored] poor design...
Only the one type of 5.4 had real issues. The others had issues like spark plugs breaking off when removing them.
I dont recall which was which.. but one had the weird plugs that would snap off on removal(and sometimes loosen).
And the other 5.4 had the ejection issue with 3 threads holding them in.
I cant remember any 4.6 that had an ejected plug issue?
The spark plug launching started with the 4.6(common on Crown Vic, grand Marquis etc), soon progressed to the 5.4...
Issue isn't the amount of threads but not being torqued properly... Too little torque the plugs will likely loosen and start "shaking" wearing the threads away(this happened from factory)... Then you have the ham fisted that over torqued, which caused the threads to pull and again the plugs loosen wearing out the threads... Poof another plug launched...
Out of seven modulars I've never had a issue, but admitedly it's a [censored] poor design...
The 4.6L/5.4L 2V share the same cylinder head design, so yeah, both are known to pop plugs. The reason the 5.4L is more known for it IDK.
The 5.4L 3V is the one with the funky plugs that break off.
Around 2003-2004 the Modular 2V engines finally went to the 8-thread heads. My '04 had 8-thread heads.
Even properly torqued they pop. I blew one out a few months ago on my '02. http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3841988/Blown_spark_plug.#Post3841988
Though, I had pulled Autolite plugs out of it, so who knows what the Sheriffs mechanics did to it.
The fact is the margin of error on the 4-thread heads is just not there. I think thats the best way to describe it. I mean, it'll hold but if something is slightly off, the chances of failure are much higher.
You have to do it perfectly.
1. Dead cold engine
2. New clean DRY NICKLE PLATED plugs
3. Torque wrench set to 120in/lbs
And still end up popping one.
The 5.4L 3V is the one with the funky plugs that break off.
Around 2003-2004 the Modular 2V engines finally went to the 8-thread heads. My '04 had 8-thread heads.
Even properly torqued they pop. I blew one out a few months ago on my '02. http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3841988/Blown_spark_plug.#Post3841988
Though, I had pulled Autolite plugs out of it, so who knows what the Sheriffs mechanics did to it.
The fact is the margin of error on the 4-thread heads is just not there. I think thats the best way to describe it. I mean, it'll hold but if something is slightly off, the chances of failure are much higher.
You have to do it perfectly.
1. Dead cold engine
2. New clean DRY NICKLE PLATED plugs
3. Torque wrench set to 120in/lbs
And still end up popping one.
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They're Autolites, like most of Ford's OEM plugs. Too bad NGK doesn't make a version, because that would never happen in an NGK.
Originally Posted By: Colt45ws
The 4.6L/5.4L 2V share the same cylinder head design, so yeah, both are known to pop plugs. The reason the 5.4L is more known for it IDK.
The 5.4L 3V is the one with the funky plugs that break off.
Around 2003-2004 the Modular 2V engines finally went to the 8-thread heads. My '04 had 8-thread heads.
Even properly torqued they pop. I blew one out a few months ago on my '02. http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3841988/Blown_spark_plug.#Post3841988
Though, I had pulled Autolite plugs out of it, so who knows what the Sheriffs mechanics did to it.
The fact is the margin of error on the 4-thread heads is just not there. I think thats the best way to describe it. I mean, it'll hold but if something is slightly off, the chances of failure are much higher.
You have to do it perfectly.
1. Dead cold engine
2. New clean DRY NICKLE PLATED plugs
3. Torque wrench set to 120in/lbs
And still end up popping one.
On the torque spec you listed- that may be the factory recommended value, but according to a repair service out there, a better torque is 29lbs. Yes, I understand that there are only something like 3 threads, but they claim to have tested them (3 thread heads) to around 100lbs torque without failure of the threads. I've done a few since reading their article and the plugs snug right down with no issues.
The 4.6L/5.4L 2V share the same cylinder head design, so yeah, both are known to pop plugs. The reason the 5.4L is more known for it IDK.
The 5.4L 3V is the one with the funky plugs that break off.
Around 2003-2004 the Modular 2V engines finally went to the 8-thread heads. My '04 had 8-thread heads.
Even properly torqued they pop. I blew one out a few months ago on my '02. http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3841988/Blown_spark_plug.#Post3841988
Though, I had pulled Autolite plugs out of it, so who knows what the Sheriffs mechanics did to it.
The fact is the margin of error on the 4-thread heads is just not there. I think thats the best way to describe it. I mean, it'll hold but if something is slightly off, the chances of failure are much higher.
You have to do it perfectly.
1. Dead cold engine
2. New clean DRY NICKLE PLATED plugs
3. Torque wrench set to 120in/lbs
And still end up popping one.
On the torque spec you listed- that may be the factory recommended value, but according to a repair service out there, a better torque is 29lbs. Yes, I understand that there are only something like 3 threads, but they claim to have tested them (3 thread heads) to around 100lbs torque without failure of the threads. I've done a few since reading their article and the plugs snug right down with no issues.
Plug blowouts occur on all three 2V mod motors - the 4.6, the 5.4, and the 6.8 V10.
Plugs can get stuck and break in the 3V 4.6 and 5.4.
Plugs can get stuck and break in the 3V 4.6 and 5.4.
Originally Posted By: The_Eric
On the torque spec you listed- that may be the factory recommended value, but according to a repair service out there, a better torque is 29lbs. Yes, I understand that there are only something like 3 threads, but they claim to have tested them (3 thread heads) to around 100lbs torque without failure of the threads. I've done a few since reading their article and the plugs snug right down with no issues.
Yikes! I might be willing to go as far as 18ft. lbs but 29 is pushing it.
On the torque spec you listed- that may be the factory recommended value, but according to a repair service out there, a better torque is 29lbs. Yes, I understand that there are only something like 3 threads, but they claim to have tested them (3 thread heads) to around 100lbs torque without failure of the threads. I've done a few since reading their article and the plugs snug right down with no issues.
Yikes! I might be willing to go as far as 18ft. lbs but 29 is pushing it.
Is it the same for F-150s? 8 threads for 2004 and later 4.6 and 5.4 V8s.
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