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Replacing the heads


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Update, Read my last post on the page for details. Thanks!

 

 

Dang i feel like i post here a lot but i have learned tons so here's the next question. Still have stripped spark plug holes on my 90 Loyale EA82, been trying to squeeze money lately by riding the motorcycle for the last 2 months. I have heard about the heila coil fix, and im not completely sold on it and am wondering the level of difficulty of just replacing the heads themselves with some down at the pick n pull? Is there different heads within the EA82 model years? Would possible an EA81 head fit? Im assuming with my limited knowledge you just drain motor and radiator, unbolt the heads and bolt up the new ones? is there tuning for the lifters involved? Am i totally on the wrong path here? Thanks

Edited by hardtail_pride
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i would try and repair the threads. have you chased them with a tap or spark plug thread cleaning tool to see if that helps?

 

if not, go the helicoil route, there's a number of tips here and probably all over the internet on how to do it.

 

pulling the heads requires some cash to do it right and it does take quite a long time. gotta pull the intake manifold, exhaust manifold, timing belt covers, a/c, timing belts, valve covers, cam carriers - which then means all the rockers fall out, then you can finally pull the heads. then reassembling is always fun, gotta clean up everything - that takes FOREVER cleaning all the heads, block, cam carriers....etc, then reinstall the cam carriers with tube sealant, squeezing them down in there without nudging the sealant on something or knocking the rockers off, which you have to hang in place while installing the cam carrier. not terribly difficult, but a huge job compared to repairing your threads.

 

you'll have to buy heads, head gaskets (see note below), have the heads milled, intake manifold gaskets, and cam carrier orings. and it's sort of silly not to replace the valve cover gaskets and some other things while you're in there.

 

if you were doing the job right and having the heads milled then it would probably actually be cheaper to pay someone $100 to repair the heads rather than all the gaskets and machine shop work. not to mention time, but i guess different folks put different values on their time.

 

it takes a long time even if everything goes smooth. run into one seized exhaust manifold bolt or an intake manifold bolt that shears off (both very common), then you're adding difficulty and time by the truck load.

 

if you do end up doing headgaskets save yourself some effort and use Fel-Pro permatorque headgaskets. anything else requires retorquing which is totally annoying.

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I was just considering my options. I didnt know if the thread inserts would be a weak link in the motor for the future. But sounds like they are stronger so i will try that route first. I did try chasing the threads but they were gone. on a couple holes. Thanks for the detailed reply!

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I seen a tidy spark plug thread repair kit at Schucks the other day. It came with at least a couple inserts and the tools to install them. I believe it was $17.

 

It prolly says so on the package/instructions but,when you cut the new threads,you can use some bearing grease on the cutting tool to catch the metal chips. You know,so they don't go into the cyl.

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Ok here is the thing i have been dancing around a bit. One of the plugs was so seized to the threads in the head, that what looks like a heli coil came out with the plug itself and left no threads in the head. So its not just the normal sized striped hole, its even bigger than normal striped hole if you know what i mean. Is there an even bigger tap and coil you can use for this or am i in a real predicament?

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Heli-coils are designed to return a completely stripped hole (no threads left at all) back to the correct thread size and pitch. They generally include a drill and a tap to oversize the hole in preperation for the installation of the coil itself.

 

So to answer your question - no that's not a problem. Trust me - I do this stuff every day. A simple heli-coil will fix your problem.

 

GD

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