Glow plug torque specs?

[Hydro Junkie]

I stripped a head button for a different reason. I didn't know it at the time but I had cooling issues due to a rudder change. Since the engine wasn't getting enough water, it softened the aluminum enough to let the threads strip at a lower than normal torque setting

 

[David Ashcroft]

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[GraysonTaylor]

Park tools makes a nice torque wrench for bicycles, 3 to 15 nm, graduated by .2 nm. 36 in/oz is 4 nm.

 

[John Beardslee]

Glenn & I did some testing at Blue Lake last week and so far the standard plugs are staying in with 36 in/oz of torque in my 91's. That's the highest torque number my nut driver style torque wrench is capable of. We did double click it which probably bumped it up a tad. This was using new compression washers each time ( Thank you Jack & Steve O'Donnell)

John

Sorry, my mistake this should read in/lbs of torque no in/oz.

 

[John Beardslee]

Grayson Ive edited my above thread, it should have read in/lbs, so 36 in/oz is too light. My JS Technology torque driver is maxed out at 36 in/lbs so I double click it. Id like to try 38 or 40 in/lbs but havent a tool to set plugs at that. I can say that I have NOT had a plug back out since using 36 in/lbs

Thanks John

 

[GraysonTaylor]

I goofed and used an inch pound converter. I must have been reading your mind. LOL. 40 inch pounds is 4.52 Nm. 36 is 4 Nm.

 

[DickJones]

Thanks Tom, I use the yellow handle T-nut driver but the lack of feeling and sensitivity in my hands and fingers makes it a real guessing game, thus my question and this thread. The standard torque spec for a steel bolt 1/4-28 thread in aluminum is 57 in/lbs, that's with 3/8" thread engagement. Our plug only have about a 1/4" engagement on a 1/4-32 thread. I only have a in/oz torque wrench down here with me but am determined to get some work done on this, stay tuned.

Thanks John

Hi John, I use 30 in .ounce. on my torque meter, I believe, most who loose a plug need to under stand what happens when u torque to a certain in. pound number and stop putting pressure on the washer to soon., I always torque to my number, after I reach it I hold my tee handle torque wrench, and count to ten seconds, and then I release the torque wrench. I have not lost a glow plug in many years!!! This locks, "stretches the threads"

Just my 2 cents worth

moby

 

[John Beardslee]

Thanks Dick

Im using a nut driver style clicker torque wrench that reads in inch pounds. Glenn Quarles and I worked on getting numbers for standard 1/4-32 glow plugs. My torque tool maxed out at 36 in/lbs, we worked our way up to that number and felt wed like to have gone a little higher but didnt have a larger torque tool so opted for double clicking at 36 in/lbs. Since using this process and number I havent had a plug come loose or stripped any threads.

Thanks John

 

[Jim Allen]

Hi John,

I use 1/4" drive, 0 to 60 in/lb, Armstrong beam type torque wrenches for tightening plugs & head bolts. Standard 1/4-32 plug threads are tightened to 45 in/lbs & 11/32-32 tapered seat plugs are tightened to 48 in/lbs. #8 SHCS head bolts are tightened to 20 in/lbs & #4 SHCS are tightened to 10 in/lbs. No loosening or thread stripping problems of any kind found thus far.

Jim Allen

 

[John Beardslee]

Hi John,

I use 1/4" drive, 0 to 60 in/lb, Armstrong beam type torque wrenches for tightening plugs & head bolts. Standard 1/4-32 plug threads are tightened to 45 in/lbs & 11/32-32 tapered seat plugs are tightened to 48 in/lbs. #8 SHCS head bolts are tightened to 20 in/lbs & #4 SHCS are tightened to 10 in/lbs. No loosening or thread stripping problems of any kind found thus far.

Jim Allen

Thanks Jim,

I no longer have a beam wrench and I think they might be a little cumbersome in the pits as well as being pronoun to damage in that environment. Your numbers are welcome, I was very surprised last January when I first raised this question on IW and got no feed back. I should have checked with you first.

Thanks again John

 

[Timbo Whalen]

https://www.amazon.com/Stanley-J6339-4-Inch-Electronic-7-5-75-Inch/dp/B00BNAMC9S

Guess we'll start buying Michigan Lottery tickets.

 

[Mark Stein]

57 in/lb is with 5 full threads

 

[John Beardslee]

57 in/lb is with 5 full threads

Thanks Mark

Are those raw numbers not taking in account the compression washer??

Thanks John

 

[brad nichols]

I personally have not used a torque wrench and over the years have not lost or stripped the threads except for one that I know was not tighten after starting motor. Is torquing the plug that critical??

Brad

 

[John Beardslee]

I personally have not used a torque wrench and over the years have not lost or stripped the threads except for one that I know was not tighten after starting motor. Is torquing the plug that critical??

Brad

Probably not for most, my problem is strictly associated with my personal hand issues.

Thanks John

 

[mr_fons]

Personally yes I did strip the threads out of a K&B 7.5 outboard head button,

did it in Montana at a race Al Hobbs use to hold around Kalispell (Crazy Al's race).

CA'ed the plug in (Jerry Dunlap was shocked I did that) gave a a minute and

started it up. I did run for about 4 laps and then the plug blew out (heat

probable and Jerry was again shocked it ran so long).

Fons.

 

[John Beardslee]

Personally yes I did strip the threads out of a K&B 7.5 outboard head button,

did it in Montana at a race Al Hobbs use to hold around Kalispell (Crazy Al's race).

CA'ed the plug in (Jerry Dunlap was shocked I did that) gave a a minute and

started it up. I did run for about 4 laps and then the plug blew out (heat

probable and Jerry was again shocked it ran so long).

Fons.

Helicoils are available in 1/4-32, I think Clarence Lee is still providing that service as hes advertising in the AMA magazine.

Thanks John

 

[LarryBeals]

There is a cool called time cert works better than others