Heli-coil went sideways on Merc 1000, now what?

[Caddy_Kid]

Ok, so I recently purchased a boat with a 1965 Merc 1000. It had a stripped out #2 sparkplug hole, which I preceded to cut and heli-coil the threads on. The good news is I didnt lock-tite anything. The bad news is, I see now that I cut the threads pretty badly to the port. The heli-coil will go in, the spark plug will even go in (although it is touching the side of the head) and when I turn the motor by hand nothing touches. Besides it looking really bad, what should I do? Time to look for a new head? Thanks.

 

[Clams Canino]

Re: Heli-coil went sideways on Merc 1000, now what?

The head is NOT removable. That thing that bolts on the back is just a water jacket cover. The head is actually part of the block, all you see of the true head is the little area around the plug.<br /><br />And Merc 1000 blocks are not easy to come by. <br /><br />If you have a decent - yet crooked heli-coil job, try putting the plug in using some aviation form-a-gasket to make sure it seals - and run it.<br /><br />Past that, you'd have to rip the whole motor doen and have an aluminum insert put into the head.<br /><br />-W

 

[Caddy_Kid]

Re: Heli-coil went sideways on Merc 1000, now what?

Oh damn, that is just a water jacket isnt it...nuts. You may ask how I was able to get it crooked in the first place. Well, the boat and trailer fits in the garage, but only if it is sideways. So this left me with about 9 inches from the back wall to the back of the motor, all at about a 120 degree angle to eachother. The job started out easy enough, but after getting a bunch of shavings on the grease about half way through, I took it out, cleaned it, re-greased it and started again. This must be where I went wrong.<br /><br />Well, as long as nothing touches and I dont lose a piston, I'll give it a shot. Hope it runs!

 

[Clams Canino]

Re: Heli-coil went sideways on Merc 1000, now what?

It may well run great......... so long as the rest of the operating paramaters are pre-set according to the "inline 6 rules". <br /><br />-W

 

[Scaaty]

Re: Heli-coil went sideways on Merc 1000, now what?

Originally posted by Clams Canino:<br /> using some aviation form-a-gasket to make sure it seals - and run it.

Yep, agreed...you just need a good seal, as the plug gasket won't be able too. You need some good high heat non-hardening (removable) sealer. Maybe try some Red gasket sealer. You'll be fine

 

[Zamboni]

Re: Heli-coil went sideways on Merc 1000, now what?

If the above fails to seal well, there may be enough room for a thin wall Key sert/Keensert type insert. Tap size is a larger than the heli-coil so if there is enough 'meat' on the head this is another option...sealant sounds easier ;>)

 

[Caddy_Kid]

Re: Heli-coil went sideways on Merc 1000, now what?

I'll give the sealant a shot. Its just dissapointing to think your trying to make something better, and just end up making it no better if not worse. But, live and learn I guess. Thanks.

 

[steviecops]

Re: Heli-coil went sideways on Merc 1000, now what?

Can someone explain how you put in a helicoil without taking the head off? I've heard of plenty of people doing it, but can't work out how it can be safe.<br /><br />I know about using grease to catch most of the shavings, but what happens to the part of the helicoil that you break off once you've wound it in?

 

[AMD Rules]

Re: Heli-coil went sideways on Merc 1000, now what?

The helicoil kit I used didn't require any of it to be broken off after insertion. The only added step required was to use the provided punch tool to swage expand the outer end as a final step.<br /><br />Came with three sizes of thread insert, the tap, and the punch tool.<br /><br />The Sav-A-Thread kit I used looked like this:<br /><br />

 

[gss036]

Re: Heli-coil went sideways on Merc 1000, now what?

http://www.timesert.com/ <br />Look at this site, I don't know anything more about them, but they work a little different than Heli-Coils.

 

[Caddy_Kid]

Re: Heli-coil went sideways on Merc 1000, now what?

My kit is the same as AMD's. They have three different sizes of coils so there is no need to cut anything. It worked very quickly on the aluminium. Too fast I guess really...<br /><br />That time-sert set is rather interesting. Wouldnt have saved me from getting it crooked, but I do like the idea of a top flange.

 

[reelfishin]

Re: Heli-coil went sideways on Merc 1000, now what?

You may want to try several spark plug gaskets to, new ones, they will tend to crush and may just be enough to seal the gap depending on how far off the hole is.
If you do add sealer, make sure it's something that you will be able to remove later to change the plug. (Don't accidently glue it in so well it won't ever come out again. I had a smaller motor in which someone got the idea that if he put the plug in with Marine Tex aluminum epoxy it would seal and just form new threads. He not only glued the plug permanent, he got the stuff up inside the plug and fouled the plug, so it never ran anyhow. On that motor I was able to pull the head, weld up the hole and retap, but a good helicoil would have been easier sans the Marine Tex mess.
On the bright side of that one, I got a very low hours motor super cheap, it did only cost me a gasket or two, some new plugs, and some time.

 

[jebeebe]

Re: Heli-coil went sideways on Merc 1000, now what?

My kit is the same as AMD's. They have three different sizes of coils so there is no need to cut anything. It worked very quickly on the aluminium. Too fast I guess really...<br /><br />That time-sert set is rather interesting. Wouldnt have saved me from getting it crooked, but I do like the idea of a top flange.

Question. Out of curiosity, what is with the "<br/><br/>" ? Is that your handle? Seems that would take a lot of complicated typing. Just curious.................Jerry