Stripped Plug Threads

[sharkhook]

On the way back from my trip I could only get about 3,000 rpm normal 4,100 at first I thought fuel,taking on water,stator,etc.

When I got back to shore I noticed fuel/oil had been flowing out of the #1 cylinder like tears. A couple of years ago I pulled this plug and half the threads came out with the plug. I quess now it's time for a repair.

Any suggestion ? Helli coils ???. Gonna surf the net for some info.

 

[Scaaty]

Re: Stripped Plug Threads

On the way back from my trip I could only get about 3,000 rpm normal 4,100 at first I thought fuel,taking on water,stator,etc.

When I got back to shore I noticed fuel/oil had been flowing out of the #1 cylinder like tears. A couple of years ago I pulled this plug and half the threads came out with the plug. I quess now it's time for a repair.

Any suggestion ? Helli coils ???. Gonna surf the net for some info.

No need to surf..any good boat shop can Heli-coil it..not a big deal...think a few$ (I do this myself)..but figure $50 or more...stuff that was $25, well , aint no more..call a few shops..

 

[Frank Acampora]

Re: Stripped Plug Threads

Check with the big auto stores for Heli-coil or other brand kits. If they don't have them, try Fastenal.

 

[sharkhook]

Re: Stripped Plug Threads

I'll check out the Heli-coil, Should I be able to knock out the re-threading without getting shaving's in the cylinder ?, Or should I be considering removing the head.

Thanks

 

[byacey]

Re: Stripped Plug Threads

Pull the head. If it was mine, I certainly wouldn't want to get aluminum shavings in the cylinder...

 

[1fullforce]

Re: Stripped Plug Threads

What Size Engine Do You Have?

 

[Frank Acampora]

Re: Stripped Plug Threads

If you re-tap the head, you damn well better pull the head.

See my private message to you.

 

[sharkhook]

Re: Stripped Plug Threads

It's an 86' 85hp. Pulling the head seems like it should only be a few minutes and it's done. But with my luck. Broke,frozen,stripped bolts. Head won't come off what else...... O yea I was talking to one of the guys at Napa and he says the head bolts are marine grade. Did I just avoid a major mistake by not using the bolts "#8" in the bin ?. I'll do it right, don't want to blow the plug out the back of the engine cover NOT COOL.

Thanks everybody, I'll keep you posted

 

[sharkhook]

Re: Stripped Plug Threads

I have the Heli-coil installed, Left the head on. I coated the channels of the bit with bearing grease I could see the shaving being sucked back away from the pistons clinging to the grease. Cleaned the hole and sealed the coil in with high temp RTV sealant. I should be ok, it looks good.

The spark plug for this cylinder looked really fouled "black smut" I'm wondering if this was result of the lost compression and unburned fuel or is my mixture to rich. Ummm well I pulled the #2 plug to compare and guess what came out with the plug YEP the threads well maybe half. I'm gonna run it on the trailer to make sure I got my power back. Confirm lost compression=lost RPM's. If so then I'll do the #2 plug.

Need to know how many pounds of torque is recommended for spark plugs. The guy at Napa Auto says about a 1/16th of a turn from finger snug.

If I can get past these issued maybe I can do some fishing.


Thanks everybody

To be continued....

 

[Frank Acampora]

Re: Stripped Plug Threads

Spark plug torque is 10-15 foot pounds OR, on a new plug, finger tight then 1/4 turn more to compress the gasket.

Since it is an aluminum head, I would use the lower value of the torque range unless it leaks.

And--uh--since #1 and #2 are heli-coiled, you might as well do #3 and get it over-with right now.

 

[sharkhook]

Re: Stripped Plug Threads

Hello all,

Took the boat out last night engine ran great. The helicoils worked great no leaks, RPM's back up to normal. I'll consider this post successful and closed.

Frank thanks for hangin in there with me, I'm almost done . Thanks again everyone for your help


Yep... Gotta start a new post "Eextremely High Idle Speed"