Heli-coil in a heli-coil ?

K

Kx_rider

Member

Mar 19, 2007

72

0

northwestern Ontario

• Sep 6, 2011

• #1

i was wondering if it would be possible to use a 3/8 heli coil in my cylinder head. and Then wind down a 5/16 heli coil into the 3/8's to make it usefull for a small bolt witch would be the 5/16" head bolt. thanks for any info.

 

IndyMX

Crash Test Dummy

~SPONSOR~

Jul 18, 2006

5,548

2

Amo, IN

• Sep 6, 2011

• #2

I'm guessing that wouldn't work so good..

What's wrong with using the right sized bolt for that helicoil?

 

whenfoxforks-ruled

Old MX Racer

~SPONSOR~

Oct 19, 2006

8,129

2

Merrillville,Indiana

• Sep 6, 2011

• #3

IndyMX said:

I'm guessing that wouldn't work so good..

What's wrong with using the right sized bolt for that helicoil?

Click to expand...

 

P

pesky nz

Member

Sep 13, 2010

296

0

• Sep 6, 2011

• #4

if you have a stripped helicoil you can get thiker inserts with the correct size thread inside (sorry don't know a brand without serching). All my experience is with metric but the pitch must be the same for one insert to fit inside another so very unlikely to work. It is not adviseable to try a tap in old helicoils as my experience says it will pick-up/ lock-up and damage will occur like a broaken tap or helicoil torn out

 

J

julien_d

Member

Oct 28, 2008

1,788

1

• Sep 7, 2011

• #5

time-sert

http://www.timesert.com/

 

K

Kx_rider

Member

Mar 19, 2007

72

0

northwestern Ontario

• Sep 7, 2011

• Thread starter
• #6

well iv ended up drilling my hole out to 3/8 but my Head bolt Is 5/16. What can i look for a fatt heli that is 3/8 fat and 5/16 threads for my bolt to thread in?

 

M

mideastrider

~SPONSOR~

Jul 8, 2006

827

1

• Sep 7, 2011

• #7

http://www.ezlok.com/InsertsMetal/index.html
http://www1.mscdirect.com/cgi/NNSRI...re=ItemDetail-_-ResultListing-_-SearchResults

There are all kinds and brands of thread inserts. I sure some will work. I would guess that your bike is water cooled, if so just be careful with large O.D. inserts that could cut into your water jacket.

 

K

Kx_rider

Member

Mar 19, 2007

72

0

northwestern Ontario

• Sep 8, 2011

• Thread starter
• #8

The EZ LOK looks like It would work. id go with a 5/16 internal and a 7/16 external the only problem i have is I dont Know which of the Thread version is the Correct one. the bike is 02 cr250r cylinder head bolt. these are the Ones to choose from, also does anyone Know where to order them online? OTHER then ebay. im thinking I need a UNC internal.

UNC
INTERNAL

UNF
INTERNAL

EXTRA
HEAVY WALL

METRIC INTERNAL/
METRIC EXTERNAL

UNC INTERNAL/
METRIC EXTERNAL

METRIC INTERNAL/
UNC EXTERNAL

AUTOMOTIVE

 

Last edited: Sep 8, 2011

M

mideastrider

~SPONSOR~

Jul 8, 2006

827

1

• Sep 9, 2011

• #9

I would use the metric internal and whatever cleans the hole up the best on the external. That way you can keep the oem hardware.
Grainger sells them I think.
or this http://www.mcmaster.com/#threaded-inserts/=dzssnp

 

K

Kx_rider

Member

Mar 19, 2007

72

0

northwestern Ontario

• Sep 9, 2011

• Thread starter
• #10

thanks for the advice. but i just want to use a standard tap. cleaning up the hole wont matter because ill drill it a bit Bigger then tap it. my Head Bolt is 8x13.5 <-- this is what i got Off a parts site. i measured the end of the stud that threads into the cylinder and the threads are half an inch long Of thread and 7 threads total.

 

Last edited: Sep 9, 2011

T

TY250

Member

Nov 30, 2005

47

0

• Apr 21, 2012

• #11

Ive had a head std pull thru the threads on a 1981 IT250. How good are the heli coils?

 

P

pesky nz

Member

Sep 13, 2010

296

0

• Apr 21, 2012

• #12

If the new thread is cut square and true with cutting oil and a stud is used (and I prefer to use studlock on the helicoil and stud) I believe better than original

 

T

TY250

Member

Nov 30, 2005

47

0

• Apr 21, 2012

• #13

ive been told not to use a helicoil, by a good mate as he had pulled out crap ones before. He did suggest using a larger stud.
Studlock? as in Locktite 242?

 

P

pesky nz

Member

Sep 13, 2010

296

0

• Apr 21, 2012

• #14

You can tell if you should get a good result when you look inside your newly cut thread and see near mirror finish in the alloy. Can't remember the number but my bottle of loctite does sy stud lock on the side and I think it is red (not 100% on the colour). The only bad resulte i've had were if the tap tore alloy (no cutting oil) or I got it off centre or there was no meat to machine (usually on Honda drain plugs)

 

P

pesky nz

Member

Sep 13, 2010

296

0

• Apr 21, 2012

• #15

almost forgot a lot of helicoils are not deep enough, when you buy them they have 2 dimensions 10/1.25-1.5 means 10mm thread 1.25 pitch and 1.5 time the thread size = the deapth (1.5x10 =15 mm deap). if you are careful you can fit 2 inserts in 1 hole but better to buy extra length to start with

 

T

TY250

Member

Nov 30, 2005

47

0

• Apr 21, 2012

• #16

I'll be leaving it to the machine shop, I'm not confident enough to do it..but I will pass on your ideas to them.
thanks.

 

T

TY250

Member

Nov 30, 2005

47

0

• May 1, 2012

• #17

heli-coil it was then, I'll let you lot know how it finally goes!
Thanks for your help..