Header bolt

Need any advice or suggestions you might have. Race this Saturday. I had to re-thread the header bolt holes. One of them works fine with heli coil, but the other, the coil will not twist down into the hole, bolt does not catch any thread when I put it into the hole. Don't know what to do to fix this...
 

flattop1

Dawg 89
You do have the heli coil tap ?
You tried a differnt coil ?
You have the install tool ?
Try turning backwards till you feel the thread drop in then forward .
Re tap / blend with dremel .
You have metric and american mixed up ?
 
You do have the heli coil tap ? Yes. The size is 6mm which is what I was told the size of those header bolts.
You tried a differnt coil ? I tried several coils and none of them worked. I went through about 7 of them.
You have the install tool ? Yes. The tool that is used to twist the coil into the hole.
Try turning backwards till you feel the thread drop in then forward . I will try this.
Re tap / blend with dremel . I'm a little worried about using a dremel on that piece.
You have metric and american mixed up ? I only have metric coils. I bought 6mm because that's what size the header bolts are?
It's strange. One hole worked fine, this other one is a pain in the ass. Funny thing is that the tool used to turn the coil into the hole is 6mm and it fits perfectly into the hole, catches the threads and screws in and out. But the coil, different story. One thing I did notice is that I bought 2 different packs of 6mm coils from 2 different stores, and they are slightly different sizes, was staring at them thinking how the hell is this possible...
 

fatboy1dh

Member
It's strange. One hole worked fine, this other one is a pain in the ass. Funny thing is that the tool used to turn the coil into the hole is 6mm and it fits perfectly into the hole, catches the threads and screws in and out. But the coil, different story. One thing I did notice is that I bought 2 different packs of 6mm coils from 2 different stores, and they are slightly different sizes, was staring at them thinking how the hell is this possible...
Do not take this the wrong way, but you do not want to mess up a helicoil and ruin your head. When we do them, it takes a lot of patience and a little finesse to get right.

I think you are beyond your skill level. Based on some of your previous posts, I am actually quite amazed you got one in and right. Get everything else on your kart 100% ready for Saturday. Show up to the track super early and start walking around the pits asking someone to help. If you have a decent group of 206 racers, someone will have the tools/parts you need to help you out. When they do, thank them and buy them a drink and a burger from the concession stand. That way they will help you again next time.
 

flattop1

Dawg 89
Dollarbill your getting better and heli coils are a task lots of people can not /will not do .
so you answered 2 of 6 questions .

the install tool is going to be 6 mm or near that as its inside the heli coil .
how can that be ; wrong package on wrong peg , wrong part in package , mislabeled package or some moron switched whats inside .
If they look different they problay are .
 

Chipg56

Member
There is a definite quality difference between Helicoil and generac, Chinese thread inserts. Make sure you have Helicoil brand. If you are trying to use a long insert try 2 shorter ones instead. They will line up with each other. A drop of oil will do wonders, especially with aluminum. You do blow out the hole with compressed air, right?
 

fatboy1dh

Member
Dollarbill your getting better and heli coils are a task lots of people can not /will not do .
so you answered 2 of 6 questions .

the install tool is going to be 6 mm or near that as its inside the heli coil .
how can that be ; wrong package on wrong peg , wrong part in package , mislabeled package or some moron switched whats inside .
If they look different they problay are .
Flattop said it more elegantly than me. You are working on an upper level task. Make sure you get some help in person and get it right.
 

Chipg56

Member
It is simple to insure you have the right heli-coil just thread it on the bolt you are planning to use, it should go on easily as would the proper nut. I would not call this an upper level task at all, but you do need to be certain the tool, insert and bolt are all the same. Skill is probably less important then patience.
 
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jjchat

Member
I have had issues with the metric heli-coil kits not working well. In the future, and to anyone else reading this who may find themselves in this position in the future, use Time-Serts not helicoils.
 
Thanks for all of the replies guys. I got in contact with someone that races at my track and is also going to be racing on Saturday. He offered to help, and mention Time-Serts that work much better. I am going to meet him at the track tomorrow. I'll let you know what happens...
 
Time-Serts are good. If you can find someone who already has the right sized kit each insert is pretty cheap. I stripped LO206 header bolts and Time-Serted them and have had no problems. I wish Briggs or some of the engine builders would offer this as an option on the LO206 (Time Sert the head before shipping).
 
Time-Serts are good. If you can find someone who already has the right sized kit each insert is pretty cheap. I stripped LO206 header bolts and Time-Serted them and have had no problems. I wish Briggs or some of the engine builders would offer this as an option on the LO206 (Time Sert the head before shipping).
The person that is helping me said they are 7 bucks each. I am meeting him later today at the track.
 
I bought some M6 time sert inserts online for about $1.50 each (probably was more with shipping) but the kit to put them in (drill bit, special tap etc) was over $70. If you can get these put in cleanly for $7 each I think that's a good deal. The head will be better than new and you'll never have problems with these again.
 
Got the header bolts fixed. Time-serts are so much easier and better than heli coils. Don't waste your time with a heli coil, they are garbage compared to time-serts. You can fix a hole in about 5 minutes. It's so easy.
 

flattop1

Dawg 89
Question : so if you tap a exhaust hole for a heli coil can you then screw a time sert in that same hole ?
albeit the counter bore part.
It seems they would be different diameters or thread pitch , though maybe not .
 
Question : so if you tap a exhaust hole for a heli coil can you then screw a time sert in that same hole ?
albeit the counter bore part.
It seems they would be different diameters or thread pitch , though maybe not .
I'm not sure about that, but from watching the hole repaired with the time-sert, the second step was to use a tool that opened the top lip a little bit because that is how the inserts look at the top. It screwed right down into the hole so easily. I was shocked. I didn't think the hole could be repaired. We took the heli coil out of the other hole that I managed to get inserted. I will definitely be looking into buying one of these kits to have on hand. It's a lifesaver..
 
Time sert also makes an oversized insert (called Big Sert) for holes that are too big for a standard time sert. These are actually much stronger than regular time serts I think though for a Briggs 206 head I'm not sure if there is enough metal to allow Big Serts to be used. It's great to have real steel threads for the header bolt. For some of the builders on the board who service the 206 head it would be neat to add a time sert retrofit as a service even for brand new engines. The time sert kit includes some proprietary tools and I'm not sure what size these are or how compatible they are with other kits.
 

jjchat

Member
Time-serts require a counter bore (which is the second step referred to) prior to threading the hole for the insert. I don't it woul work if a heli-coil had already been inserted and then removed. Might be able to be cleaned up with a thread chaser well enough to put in the insert.
 
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