help I may have cross threaded the top spark plug cyl

[my new fishmaster]

I can get the plug in half way then it stops. I have noticed some of the threads coming loose. Should I force the plug in there or do you have any suggestions. If I do need a new engine head are they easy to install.

 

[norman158]

Re: help I may have cross threaded the top spark plug cyl

dont force the plug i would pull the head and take it in to your favorite machine shop and have a helicoil put in it or buy the kit and do it yourself <br />Rick

 

[byordy]

Re: help I may have cross threaded the top spark plug cyl

I agree, don't force the plug. If the threads are coming loose you may have to have a helicoil installed, but you might try running a thread chaser into the hole. Coat it with grease to catch any debris and work carefully. If you have enough good threads left this might fix it. Thread chasers are available at auto parts stores. I just bought one at Discount Auto Parts to use on my 5.5 hp Johnson and it seems to have worked ok.<br />Bill....

 

[my new fishmaster]

Re: help I may have cross threaded the top spark plug cyl

I have the plug in now and used my vaccum to remove any metal threads. I sprayed some storage oil around the plug and there are some bubbles? It might make sense to just purchase a new head and do it my self. What are the torque sequence. Just what is a helicoil?

 

[norman158]

Re: help I may have cross threaded the top spark plug cyl

a helicoil is a threaded insert that can be installed in a striped hole to repair just the problem your having i would try it first much cheaper than a new head <br />Rick

 

[my new fishmaster]

Re: help I may have cross threaded the top spark plug cyl

I am worried that adding a heli would change the compression. What are the chances that it would sit flush. I looked up Mercurymarine.com entered my model oe177457. Do I need only the #29 cover-cylinderhead for $35.95 is this what the plugs screws into. Or do I need the#24 head kit-cylinder. Has anyone ordered from mercury parts express before.

 

[norman158]

Re: help I may have cross threaded the top spark plug cyl

adding a helicoil wont change the compression all it does is repair your damaged threads i would think you would need the whole head kit <br />Rick

 

[Fouled Plug]

Re: help I may have cross threaded the top spark plug cyl

A helicoil won't change the compression. As far as the new parts, I do believe you would need the cylinder head itself, as the plug threads into it. At $150 or so for the head, it's way cheaper to go the Helicoil route.

 

[ka3wld]

Re: help I may have cross threaded the top spark plug cyl

Check out eBay for heads. I just won a pair supposingly in excellent condition for $9.95!<br />Type in Search, Boating, than Parts/maintenance/engines. Good luck!

 

[my new fishmaster]

Re: help I may have cross threaded the top spark plug cyl

Thanks for everyones help if I decide to take the head off myself anything I should lookout for. It seems there is a cover,head and a gasket that mates to the block. I am going to sears to pick up a tourque wrench,locktite. Should I use a small amount of high temp rtv to hold the gasket on while I line up the bolts.

 

[my new fishmaster]

Re: help I may have cross threaded the top spark plug cyl

Also is there a torque sequence for the head bolts the year is 96 75hp force. I have the clymer manual not the factory service. <br /><br /> http://www.mercurypartsexpress.com/PartsExpress/ProductSelection/ServicePars/imagefile...

 

[dmessy]

Re: help I may have cross threaded the top spark plug cyl

Check out your manuel for cylinder head replacement. DO NOT use locktight or gasket sealer! First clean out the thead holes in the block, then clean it bolts(making sure that the same bolt goes back into the same hole). Then lightly oil the bolt theads AND the bottom of the bolt head with clean oil. You then retorque the bolts to 120 inch pounds then turn them 90 degrees more. This Force motor uses this torque and turn method. Follow the instructions to the letter in your Clymer manuel for cylinder head checking and replacement. Just did mine and it runs GREAT! Good luck...