E90TLCOS - Spark Plug thread is done

[oviana]

Hey folks,

Need some help. Not sure how to do this repair, so if you can suggest, I am a good listener hummm ... reader.
I decided to replace the sparks on my Evinrude outboard. It's a 1985 90HP VRO model CE90TLCOS.

On the last spark, it kept spinning. I was using a torque wrench, and was tightening to 230 ft/lb of torque. My understanding is that the spec calls for 240 ft/lb.

Anyways, I'm now left with the need for a repair, and think that I can do it myself. A couple of questions:

1. Do I need to pull out the cylinder head, or can I repair it as is?
1a. And if so, how do I go about this process? I've never done this before.

2. Does anyone know what the torque spec for the cylinder head is, if I do decide to pull it out?

Thanks very much for any insights!

Ozy

 

[racerone]

Re: E90TLCOS - Spark Plug thread is done

Where did you get that torque value ???????????????------It is 17 FT-LBS for a sparkplug.

 

[Grantspec]

I think you are confusing inch lbs and foot lbs. 240 Inch lb = 20 foot lb

 

[wrench 3]

I think you got FT-LBS and Newton Meters mixed up! 17 FT_LBS is 230.something Newton Meters.
I don't see any of them not stripping at 240 FT-LBS. So I'm not sure what you torqued them at.
Most automotive parts stores can give you a choice of repair kits to fix the problem with the head on. Or if the complete kit is too expensive, their machine shop could install the insert for you.

 

[Chris1956]

Ozy, It is best to pull of the head and drill and tap it for a solid insert. If you try to drill and tap it while it is on the motor, and some metal shavings can get into the cylinder, you will have worse problems.

 

[Vic.S]

I think you got FT-LBS and Newton Meters mixed up! 17 FT_LBS is 230.something Newton Meters.
.

I think you have that conversion wrong

1 pounds feet is 1.356 newtons metre

so 17lb ft = 23 Nm

 

[a70eliminator]

240 inch pounds I would presume. Foot pounds of that value will tear out every fastener on that motor with the exception of the flywheel.

 

[daselbee]

240 inch pounds I would presume. Foot pounds of that value will tear out every fastener on that motor with the exception of the flywheel.

Yes, exactly right....not to mention the sheer size of a torque wrench that is capable of 240 ft-lbs.

 

[a70eliminator]

To apply a torque wrench capable of pulling over 200lbs to a spark plug in an aluminum or even cast iron head for that matter really shouldn't be tinkering with mechanical stuff, sorry but really that's how I see it, you'll now have to hire a professional to install a thread insert to restore the damaged head and it will be good as new.

 

[oviana]

Sorry guys. You're absolutely right. I meant to put in-lb, and instead for some dumb reason put ft-lb on the post.

I torqued it to ~ 230 in-LB (~ 19 ft-LB) torque, and even at that torque it stripped.
I spoke with my brother-in-law who's a car mechanic, what he says is it likely happened end of season last year.

I had the engine running and while it was still warm, I pulled the spark plugs to put in some fogging oil in the cylinders.
I then replaced the spark plugs but didn't torque them. Instead, I torqued them this year and that's when this happened.
I'm waiting for a Heli-Coil kit from amazon, and will be fixing it probably next week or so. Should work well, I hope.

I've never done this before, but I watched a video on Youtube on the procedure { https://www.youtube.com/watch?v=A78Ve-cHYyo }, seems to be a relatively simple thing to do.
I'm a pretty handy guy with my own share of tools; do some car repair myself (though lite). Can't believe I put in ft-LB, when I meant to say in-LBs. LoL

Thanks again for all of your replies!!

 

[wrench 3]

A solid insert is better than a Heli-Coil for something that will be taken apart every year. But a Heli-Coil will work.
If your doing it with the head on, put heavy grease on the tap to hold the shavings and don't drop the tab when you break it off of the coil.

 

[boobie]

The best torque spec I ever heard of was from and old aircraft mechanic. He said put the plug in until it seats and then give it a 1/4 turn. Used this myself for many years .JMHO.

 

[Quick3201]

You can do the repair with head still on motor. Be sure piston is completely down in cyl, put heavy grease on drill bit, drill slowly, blow out cyl, put heavy grease on tap, proceed slowly, blow out cyl, Clean threads with "brake cleen" Install your choice of thread repai with lock tite. Hope this helps. I did a lot of these repairs when auto heads started coming in alum.

 

[daselbee]

The best torque spec I ever heard of was from and old aircraft mechanic. He said put the plug in until it seats and then give it a 1/4 turn. Used this myself for many years .JMHO.

Boobie... some new plugs come with a washer that crushes when first used.
Is this 1/4 quarter turn extra for new plugs, or just when re-installing old ones?

I like the concept, but wonder if the washer will crush with a 1/4 turn....

 

[boobie]

I've used it for both old and new.JMHO

 

[ondarvr]

The washer are supposed to be replaced every time the plug is removed, I can't say many people do that though.

 

[MikDee]

Always remember never to take spark plugs out, or put them in, on an Aluminum head engine when it's even Warm! Do it carefully when stone cold.

 

[boobie]

Did you ever try to take the washers off of the newer plugs when they have been used ?? Years ago you could and the parts houses sold them.