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Conference vicki::boats

Title:	Powerboats
Notice:	Introductions 2 /Classifieds 3 / '97 Ski Season 1267
Moderator:	KWLITY::SUTER

Created:	Thu May 12 1988
Last Modified:	Wed Jun 04 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	1275
Total number of notes:	18109

680.0. "Exhaust Manifold Removal" by DNEAST::OKERHOLM_PAU () Thu May 31 1990 13:06

	I really did it to myself this time. I was replacing a simple little
shock mount between the cowling mounting bracket and the exhaust manifold cover
on my outboard. While attempting to loosen a piece which was stuck I managed 
to break the mounting bracket which was cast into the 
exhaust manifold cover.
	I have a couple of options:

	1. Leave it alone.

	2. Fashion a stainless steel tab to utilize one of the mounting
	   bolts on the manifold cover. I could then mount the shock mount
	   to the tab.

	3. Replace the manifold cover and assorted gaskets. (<$40)

	Since I never was one to leave things alone, my first choice is #3.
Its worth the $40 to avoid hassle of making the tab etc.. Also choice #2 
still presents my most formidable challenge, that of getting the bolts 
loosened. 
	Now to my question: has anyone had experience with removing an exhaust 
manifold assembly from an outboard which has seen considerable salt water use?  
My major fear is shearing off bolts in the process. The shop manual assembly 
instructions say to torque them down to 180 ft lb and use Locktite as well, so 
those suckers are in there tight.
	I will probably soak the hell out of the bolts with liquid wrench for 
a couple days but I'm still fearful. Any help would be appreciated.
Regards,
Paul

T.R	Title	User	Personal Name	Date	Lines
680.1	Winter project	TIMES2::URBAN		`Thu May 31 1990 13:39`	4
	Wow...180 ft lbs, Loctite, heat embrittlement, corrosive effects of salt...I think I'd take option 1 or 2 until the fall and make it a winter project when there would be plenty of time to repair what might break.
680.2	Tighten 'til it breaks, then back off 1/2 turn	FAIRWY::WILSON	It's sum-sum-summa time!	`Thu May 31 1990 13:47`	15
	RE: >> My major fear is shearing off bolts in the process. The shop manual assembly >> instructions say to torque them down to 180 ft lb and use Locktite as well, >> so those suckers are in there tight. ^^^^^^^^ Paul Are you sure that's what the manual says!? You're talking about a 2-3 foot long breaker bar to apply 180 foot/pounds of torque. There's no aluminum block I've ever seen that could withstand that much torque on the threads. I've been wrong before (more than once...), but maybe the manual says inch pounds? That would be around 15 foot/pounds, which sounds much more appropriate for threading into an aluminum block. Rick W.
680.3	something doesn't sound right	CSMET2::CHACE	is it getting warmer?	`Thu May 31 1990 14:14`	15
	180 FOOT POUNDS!!!!?!?!?!?!?!?!?!?! Even the flywheel nut on an outboard doesn't get torqued to that! I bet it's 180 INCH pounds (and even that sounds high) I have removed the exhaust covers/deflectors/housing (I wouldn't really call it a manifold in the automotive sense of the word) before from an outboard that was used ONLY in salt water and had an internal water leak that caused it to seize very well over the winter. The manifolds came out quite easily, but I would still say that if you can get around it easily, DON'T take it apart! Kenny
680.4	try this...	HYEND::J_BORZUMATO		`Thu May 31 1990 14:59`	9
	I'll bet on the inch pounds as well, aluminum won't take much more. On the liquid wrench its ok, but try the NAPA penetrating oil, you won't belive it. I tried it for the first time last season, a friend of mine let me borrow it, unbelievable. Jim.
680.5	Inch Pounds It Is	DNEAST::OKERHOLM_PAU		`Thu May 31 1990 16:16`	19
	You're right, its inch pounds. I just rechecked the manual. (I thought 180 ft lb sounded high but I don't deal with torque measurement every day.) Now that we have established that its 15 ft lb I don't feel so bad. When I rechecked the manual I looked up a few other torque specs to give me a feel for how tight they are; a few examples follow. Spark Plugs 17 ft lb Flywheel lock nut 100 ft lb Cylinder head bolts 30 - 40 depending on design Since its about the same as spark plugs and the bolts are likely stainless steel I think I'll try a little conservative de-torqueing. Thanks for the quick response. Even though I feel a little embarrassed at missing an obvious error, I certainly have profitted from the information. Regards, Paul
680.6	slow and steady undoes the bolt...	SALEM::LAYTON		`Thu May 31 1990 16:28`	7
	When removing fasteners, the temptation is to use a whole bunch of effort all at once. This is how we break sockets and strip and break bolts. Much more effective is constant moderate force for a longer duration of time. If glue, cement, or loctite are used, the bond slowly gives way in a minute or three. Carl
680.7	OSCO replacement manifolds.	WEFXIT::SUTER_P		`Tue Apr 09 1996 10:41`	13
	I know someone in the file was asking about replacement exhaust manifolds, which prompted me to increase my mild concern about mine to the point of ordering and OSCO catalog..... Anyway... I got the catalog today... Replacements for my 351 PCM are $165.00 each. Not "too" bad... Be glad to look up any others./.. Rick ps. Boy, am I having a hard time finding notes lately... must be CRS.!
680.8	Exhaust Leak? manifold replacement?	WEFXIT::SUTER_P		`Tue Apr 09 1996 11:09`	19
	Ok, now I'll ask the same question...... I was very happy to find that my "little ticking noise" from the right valve cover/Exhaust manifold area is truly a simple exhaust manifold problem. Not too hard to diagnose as it's to the point where you can FEEL the leak if you place your fingers down beside the manifold. :-) Anyone removed a fresh water manifold from a 9 year old boat lately? Should I expect to break bolts? Is this a winter job? Also, what about the life of your typical V8 manifold, should I consider simply replacing the manifolds themselves while I'm at it? thanks, Rick