Helicoil?

DJAY2003

Cadet
Joined
May 8, 2003
Messages
11
Hey Guys, need boat in water tomorrow. Have small fuel leak from #4 sparkplug. Can it do any damage to run like this? How long does it take a helicoil to set\cure? As long as everything goes ok, whats the average time to fix with the helicoil? Half of the threads are still there. Thanks in advance.<br /><br />Daryl<br />1965 90hp Johnson
 

jim dozier

Lieutenant Commander
Joined
Jan 8, 2003
Messages
1,970
Re: Helicoil?

I think you have to remove the head to set a helicoil. You have to drill out the old threads, retap it with a larger tap, and screw in the helicoil. Its the shavings from the drill and tap that require the removal of the head. I've never actually done a spark plug just a lot of bolt holes but I think its the same. If anyone knows how to do it with the head on I'm sure they will chime in.
 

rolmops

Vice Admiral
Joined
Feb 24, 2002
Messages
5,518
Re: Helicoil?

Hello.<br />It is a good idea to remove the cylinder head,that way shavings will not scratch up your cylinder wall.I have heard of people having the piston most of the way up shoving some cloth inside and packing the top with heavy grease.Rethreading is much easier and safer when done on a flat surface where you have full control.You must use red silicone when you screw the helicoil in and as far as I remember, let it set overnight.<br />I was in a hurry and did not follow my own better judgement.The end result was having to buy another cylinder head,which by the way is the fastest solution.<br />Small fuel leaks can make big fires.<br />good luck.
 

SlowlySinking

Master Chief Petty Officer
Joined
Oct 31, 2002
Messages
897
Re: Helicoil?

jimd has the procedure right on, Since time is short and some head threads are left you could try some high temp sealer on the plug threads and don't over tighten the plug, give it a go, little to lose and it buys some time. I've never been successful doing this without pulling the head. Tried it and the drill shavings jam between the piston and head, makes quite a racket, probably doesn't help the crank bearings too much. ;)
 

DJAY2003

Cadet
Joined
May 8, 2003
Messages
11
Re: Helicoil?

Thanks for the quick replys. Will try your advice Slowlysinking, and if it does not work, oh well, will have to wait till next weekend. :( Will pull the head to fix. Better safe than sorry. Thanks again.
 

DJAY2003

Cadet
Joined
May 8, 2003
Messages
11
Re: Helicoil?

This actually was a simple job. Head was easy to get to, tapping went smoothly, and the insert is working just fine. With all the mess it created, I was glad I pulled the head. Total cost to inlude hi-temp sealer-$3, heli-coil kit-$29.99 [w/extra inserts] and head gasket $22. Saved bookoo bucks by doing it myself with help from the info. I got here. Thanks!
 

dakk1

Chief Petty Officer
Joined
Apr 22, 2003
Messages
418
Re: Helicoil?

Djay<br /><br />Your right, pulling the head is definitely the way to go. My local outboard mechanic put one in for me. I pulled the head and he installed the Helicoil for $25. Took him about 10 min tops and there was quite a pile of aluminum shavings that I'm glad were on his workbench and not in my cylinder! LOL
 
Top