Who has installed Helicoils ?

[Sea Rider]

On stripped crankcase's cylinder head threads, want to ask a tech question regarding installation...

Happy Boatinhg​

 

[dingbat]

On stripped crankcase's cylinder head threads, want to ask a tech question regarding installation...

Happy Boatinhg​

Installation is pretty straight forward.

What is your question?

 

[matt167]

drill the hole to the required size, tap with the heli coil tap, insert the coil with the little installation tool.

Time Sert may be a better install, but I've never used them

 

[Sea Rider]

Installation is pretty straight forward.

What is your question?

Have a Blind threaded orifice as shown. It's 16 mm deep, have 15 mm length Helicoils to sort that out nicely.


when installed and tested on a hard wooden block, once the Helicoil's thread was nicely coiled into the wooden threads the Helicoil has extended 5 mm more to 19 mm and covered the total wooden width length. It's not stated if the Helicoils will lengthen farther than when compressed prior installation. Seems will go that route when installed on the stripped orifice thread which is metal.



Wanted to know if once the Helicoil is installed a new bolt will be easy to be fingered coiled ? The issue is : if expands will be easy to finger screw as the wooden test showed, if doesn't expand and once installed on a metal surface the bolt seems to go in tight will need a wrench.

Have 2 alternatives : risk installing an M8 x 1.25 x 15 mm length Helicoil and trim the excessive amount exiting the orifice with whatever is needed or install a M8 x 1.25-16 mm Time Sert with removed head to be 15 mm in length and be able to be screwed fully coiled inside the 16 mm depth thread shown in pic and avoid any further issues and time loss going for the Helicoil. Don't have the special tool to drill and expand the beginning of the orifice for the protruding round head to sit flat on the metal wall once fully screwed in that's why a small length resize without the head is needed.

Happy Boating​

 

[Texasmark]

I'd do the work Matt recommended and then install whatever length you have and when finished take a 4 or 4 1/2" cut-off wheel and trim to fit. The usual practice is to knock the tang off the bottom after insertion but since you are bottoming out seems like a moot point.

Another option is to drill the hole deeper. Even if you break through to the water chamber, Permatex#2 will seal the threads.

 

[dingbat]

Have a Blind threaded orifice as shown. It's 16 mm deep, have 15 mm length Helicoils to sort that out nicely.
View attachment 352178

when installed and tested on a hard wooden block, once the Helicoil's thread was nicely coiled into the wooden threads the Helicoil has extended 5 mm more to 19 mm and covered the total wooden width length. It's not stated if the Helicoils will lengthen farther than when compressed prior installation. Seems will go that route when installed on the stripped orifice thread which is metal.

View attachment 352172

Wanted to know if once the Helicoil is installed a new bolt will be easy to be fingered coiled ? The issue is : if expands will be easy to finger screw as the wooden test showed, if doesn't expand and once installed on a metal surface the bolt seems to go in tight will need a wrench.

Have 2 alternatives : risk installing an M8 x 1.25 x 15 mm length Helicoil and trim the excessive amount exiting the orifice with whatever is needed or install a M8 x 1.25-16 mm Time Sert with removed head to be 15 mm in length and be able to be screwed fully coiled inside the 16 mm depth thread shown in pic and avoid any further issues and time loss going for the Helicoil. Don't have the special tool to drill and expand the beginning of the orifice for the protruding round head to sit flat on the metal wall once fully screwed in that's why a small length resize without the head is needed.

Happy Boating​

You lost me with all this talk of wooden dowels, finger tight, etc….

You can’t half butt the install of a helicoil in a high torque applications. I would highly recommend having the insert installed professionally using the appropriate, drill size, tap and insert

To answer your question….helicoils are stronger than the base metal.

The length of the heli-coil is determined by the type of material your installing the insert in and torque the insert is required to hold. It is rare, if ever, that you need to match thread counts 1:1….

Here is a insert length calculator. Can’t tell from the picture of the block is cast steel or cast aluminum. You will need to determine the material of the casting and its shear strength to calculate the appropriate insert length and drill size.

Helicoil Length Calculator

Here is the data sheet of the lengths and options once you determine the insert requirements

http://www.noblefix.com/PDF/Helicoil/HeliCoil-Catalogue.pdf

 

[Faztbullet]

So your expoy fix didnt work?

 

[racerone]

Helicoils are elegantly simple to install.----After all they have been around for more than 50 years.----If there was an issue it would have been corrected years ago.

 

[Sea Rider]

The idea is to DIY work with the right tools, the guy who has been installing Helicoils for decades passed away. The stripped thread has been already drilled and the tapping is pending, don't want to drill further down with a pointy drill because will be drilling the water passage located at the bottom of the orifice and don't want to go that route.

What asked is simple, when the Helicoil has been properly installed flat against the metal edge, will the new bolt be possible to be screwed fully in with least thread restriction or the Helicoil's internal threads will remain tighter against the bolt's threads in which case will need a wrench which it's not an issue.

If with least bolt restriction would prefer a zillion times to screw in a Time Sert pre cut to size prior installation which has minimum thread restriction and bear with it. The Helicoil's drill and tap being same diam will accept a perfect Time Sert install along new bolts as have already tested.

The alum putty temporal fix worked OK, down issue was not being possible to torque that M8 bolt to 30 NM before the large headless bolt pulled the remaining internal threads off the orifice. If I would have re torqued all the head bolts to slight more torque values than what the factory calls for way before the break end period ended and not 600 run hours after the motor wouldn't have salt seized threads and broken 3 bolts heads in a row while pulling the cylinder head out. If you retorque all gaskets bolts from time to time that won't happen, but who does it ? no one, that's why everybody is in fear of breaking bolts when in need to install new gaskets in. For me that awful scenario won't happen ever again.

Thanks Dingbat for the Helicol information, highly appreciated, the issue is that don't have that many sizes to choose the right length one, will need to work with the current one already have. If in need to remove an Helicoil ot Time Sert out a threaded orifice is there a special tool that's required for that task to order one ?

Happy Boating​

 

[flyingscott]

If you install the heli coil correctly it will work the same as a threaded hole. Should easily be able to put the bolt in by hand and then torque it. Make sure you drill and tap it straight. Head bolts are NOT a high torque area the helicoil will work fine. Just a lot of overthinking of something really simple.

 

[Texasmark]

If you install the heli coil correctly it will work the same as a threaded hole. Should easily be able to put the bolt in by hand and then torque it. Make sure you drill and tap it straight. Head bolts are NOT a high torque area the helicoil will work fine. Just a lot of overthinking of something really simple.

It will work better because it's SS not cast alminum and its slicker so it's easier to get the correct torque....like wet and dry thread torques on bolts.

 

[flyingscott]

It will work better because it's SS not cast alminum and its slicker so it's easier to get the correct torque....like wet and dry thread torques on bolts.

Thank you for mansplaining to me.

 

[dingbat]

Thanks Dingbat for the Helicol information, highly appreciated, the issue is that don't have that many sizes to choose the right length one, will need to work with the current one already have. If in need to remove an Helicoil ot Time Sert out a threaded orifice is there a special tool that's required for that task to order one ?

Happy Boating​

Two things that mess with the installation….walking the tap drill (out of round) and not starting the tap perfectly perpendicular to the hole.

I prefer to sit things up in a milling machine and dial in the part but a good quality drill press will suffice.

Drill, tap and install the insert in one setup w/o moving the part.

Pain in the rear to remove once you break the tang off. At that point the machinist would usually take the part back to the welder (Dingbat) to deal with…TIG weld SS screw/bolt in insert to facilitate removal

 

[Faztbullet]

I have reinstalled the head and used it as a guide plate before. Secret is correct bits and cooling oil (kerosene). Need a 118° Helical tip not the one in the kit

 

[Sea Rider]

It's not that's been overthinking the whole issue too much, that's new territory to me that needed to be fully understood to work right from the very beginning.

Now know that Helicoils expands when screwed in and need to order and install shorter ones as to fill the whole orifice depth and avoid triming the coils excess that will surely protrude when installing longer ones in.

According to both Helicoil and Time Sert physical tests done, new cylinder head bolts were fully screwed in with no resistance with just fingers. Thought that Helicoils achieved a tighter thread/bolt fit which didn't.

The previous orifice and drill bit were well oiled before being drilled straight perpendicular with a vertical alignment tool place on top orifice's edge, will do the same procedure with the tap. The pointy drill tip that comes in the kit it's useless on short non deep blind holes. Hey FB can you post a pic of a 118 deg helical tip to have a look how it looks like. Seen YT videos using a pedestal drill to drill straight orifices. Thanks all.

Happy Boating​

 

[flyingscott]

Take it to a machine shop. This post has gone on way to long for something as simple as a heli coil. If drilling and tapping make you uncomfortable they are cheap to have installed.

 

[racerone]

???----Why would you not cut / file a couple of coils off if the thing is too long ????----I agree find someone who has more expertise on this simple topic.

 

[Sea Rider]

Will be better to leave this post alone, all what needed to know have already been tecnically replied. Will post end results when the job is finished installing a Time Sert which feel more comfy to work with...

Happy Boating​

 

[flyingscott]

Will be better to leave this post alone, all what needed to know have already been tecnically replied. A pity that has taken so long mainly due to not responding precise and concrete answers to what was asked. Will post end results when the job is finished...

Happy Boating​

Really let me clarify for you the heli coil installation for you.
#1 Get Keys
#2 Start car
#3 load car with required parts needing repair
#4 drive to machine shop
#5 Pay machine shop
#6 Load repaired parts into car
#7 Start car
#8 drive home
#9 put car keys back where you found them
# 10 install repaired parts on boat.
There you go heli coil installation in 10 easy steps.

 

[Sea Rider]

Really let me clarify for you the Heli Coil Installation for you.

Are my post so complicated to read, what is it that your brain doesn't fully understand. There's no more machine shop. I'm going for a Time Sert install, not an Helicoil install. Two different scenarios. one easier than the other so don't play being funny on line. BTW, have you joined FB's fan club to ridicule me in Stereo ?

Happy Boating​