Replace rusty bolts without renewing gasket

[dougs40]

I noticed the heads of the main bolts holding the power head unit to the Leg (main mid section/driveshaft)were badly corroded.<br />This is on a 40 HP Johnson approx. year 1995 ? sn:=BJ40TLE0D two stroke.<br />My question is 'can I replace them, say one at a time thus hopefully not having to disturb and replace any gasket?'<br />They look so badly corroded that if they are left any longer there will be insufficient metal for any tool to remove them!<br />I suspect I know the real answer, but surely one bolt at a time should not disturb the gasket?<br /><br />I assume (from the Clymer manual I have) there are no nuts on the top and that these bolts go into the power head?<br /><br />If I can replace them, do I use Stainless bolts ?<br />and are they metric or ?<br />Any thread locking compound or ?<br /><br />thanks for any advice,<br /><br />Doug.

 

[rickdb1boat]

Re: Replace rusty bolts without renewing gasket

I don't see why you could not replace them one at a time, then retorque them all to specs without a problem. If you have a dealer near you, I would get the bolts from them. They do go into the block and there are no nuts. Stainless would be the way to go. At least later on if you need to remove them, it will make it alot easier...

 

[dougs40]

Re: Replace rusty bolts without renewing gasket

Thanks Rick,<br /><br />What I had in mind was to change one, torque it up, change the next one in any specified sequence the manual may have (not checked yet), say typically diagonally opposed (sp) much like torqueing up a car cylinder head.<br /><br />Got this bad feeling though that the rust may have gone too far, is this normal, or has it rusted quicker due to any annode/cathode, anyway I shall check with the dealer when ordering up the bolts.<br /><br />Doug.

 

[OBJ]

Re: Replace rusty bolts without renewing gasket

The problem I have with this is, if the corrosion has gone back into the threads, you may snap one off. Then ya' gotta take the head off. If you do get them all out and the corrosion is still back in the threads, your not going to be able to clean them out and will have to replace the new bolts back into the corrosion. This would make getting an accurate torque difficult.<br /><br />Why not just remove the head, chase out the threads with a tap. This will clean up the threads and straighten any that may be damaged. Also this will let you get a good look at the cylinders and see what shape they are in.<br /><br />The head gasket runs around $29 dollars US.<br /><br />Just my $.02 worth.<br /><br />Good Luck and let us know how ya' make out.

 

[rickdb1boat]

Re: Replace rusty bolts without renewing gasket

Good Advice OBJ What was I thinking????

 

[OBJ]

Re: Replace rusty bolts without renewing gasket

No problem Rick....we all have...."Senior Moments".....LOL!!!