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Redneck
06-18-2008, 10:39 AM
Well the ice is finally gone and time to hit the lakes. Does anybody know the bolt torque specs for the exhaust manifold. I have a 2007 outback V the left manifold started leaking so I need to fix it. It does not make sense to take it to a dealer as I live to far away. I asked my dealer about it and he said "Just make them tight" and if you can believe it I was talking to the mechanic. I have searched the froums and the internet for the specs but no luck so any help would be great.

Thanks

seanpatsdad
06-18-2008, 04:51 PM
I would give the guys at Discount Inboard Marine a shout.They will have an answer.
www.skidim.com

John

bobwells
06-18-2008, 06:11 PM
you must not be as "red" as you think ! LOL, thats good solid shade-tree advice. just use some good common sense on torqing sequence... not near as critical as some other parts... I'd keep rotating a good balanced tightning sequence, after all is bottomed out good go back over them one last time, run it for a day, then re-check'em. Just dont use a huge pull handle so as to over leverage and twist a bolt off ... YOU CAN DO IT!!! :-)

Engine Nut
06-18-2008, 09:25 PM
Well the ice is finally gone and time to hit the lakes. Does anybody know the bolt torque specs for the exhaust manifold. I have a 2007 outback V the left manifold started leaking so I need to fix it. It does not make sense to take it to a dealer as I live to far away. I asked my dealer about it and he said "Just make them tight" and if you can believe it I was talking to the mechanic. I have searched the froums and the internet for the specs but no luck so any help would be great.

Thanks

I assume you have the cast iron exhaust manifolds. Indmar does not use a gasket between the manifold and the head on those units. A bead of hi-temp silicone sealant around the exhaust ports is all that is needed. Tighten the bolts starting in the center and work your way out. First pass to 11 foot pounds and second pass to 22.

maxpower220
06-18-2008, 11:15 PM
http://www.raskcycle.com/techtip/webdoc14.html

Every bolt has it's own torque setting based on its size and thread. Torque to Yield is slightly different, but there is a chart for those also.

Redneck
06-19-2008, 02:07 PM
Thanks for the input people. Engine nut gave the torgue spec I was looking for. Keep up the good work.

Time for the lake.

zegm
06-21-2008, 01:26 PM
If you know the bolt size you should be able to look up standard torque values for the size bolt. Hit the internet and do a search for bolt torque values. This will work fine as both the manifold or block are standard types of materials, ie not aluminum or any other soft material that would need special considerations.

squeeg333
07-01-2011, 01:07 PM
So, this is a super old thread, but I'm bringing it back. I had a leak from my port side exhaust manifold, and went to fix it. Ordered a gasket kit from skidim. Well, when I pulled the manifold off, I saw what Larry here was talking about - no gasket - just RTV. So, I installed everything back together with the new gasket. Do you all think this will be alright? Or should I just get some high temp silicone gasket stuff?

I would think the gasket that I put in would do just as good, if not a better job than RTV, but I don't know. You guys have any input??

kaneboats
07-01-2011, 02:02 PM
I don't see why a gasket would not work fine.

squeeg333
07-01-2011, 02:13 PM
That was my inclination Kane. I figure they make this gasket for a reason, specifically to fit an Indmar Assault 5.7L V8. So, it's sold for a reason!!

squeeg333
07-01-2011, 03:04 PM
I am also slightly confused on the torque spec for the manifold bolts. Larry here say 11 and 22 ft pounds. I talked to the customer service guys at Indmar yesterday, and they said 3 passes - 27 in-lbs; 106 in-lbs; and then 11 ft-lbs. Thats where they sit now... but not sure if I should take them up to 22 ft-lbs or not.

kaneboats
07-01-2011, 04:11 PM
I would not doubt anything from Larry. BUT, if you are putting the gasket in I can see why you would not need to torque as hard.

maxpower220
07-01-2011, 05:10 PM
Your gasket will be fine. Make sure that it is a stainless steel insert, as it will hold up better in the marine environment.

squeeg333
07-01-2011, 11:00 PM
Well, it was actually just a plain gasket, no insert at all. It was made of some sort of papery material. I did some research before I put it in, and it's some sort of matrix. Not sure, but sounds good.
Anyway, got everything buttoned up (torqued in the middle of recommendations from Larry at Indmar, Customer service at Indmar, and SkiDim - about 18 ft pounds). Fired it up in the driveway this afternoon, and seemed to work just fine. I didn't let it get up to operating temps, but will tomorrow, and see what goes down. Thanks for ya'lls help, and if something happens, I'll let you guys know!

Engine Nut
07-03-2011, 02:41 PM
I am also slightly confused on the torque spec for the manifold bolts. Larry here say 11 and 22 ft pounds. I talked to the customer service guys at Indmar yesterday, and they said 3 passes - 27 in-lbs; 106 in-lbs; and then 11 ft-lbs. Thats where they sit now... but not sure if I should take them up to 22 ft-lbs or not.

The 11 foot pound torque is for the intake manifold, not exhaust. Using a gasket is OK but the RTV works very well. We have been building engines that way for the past 30 years or so. There is no Flow of water between the cylinder head and the exhaust manifold so if you have water dribbling out between the exhaust manifold and cylinder head it is either coming back in through the exhaust or the riser gasket is leaking.

squeeg333
07-05-2011, 04:41 PM
Interesting. It was very clearly leaking from the furthest to the bow end of the port side exhaust manifold, between it and the engine. When I went to pull it apart, I could see why - the manifold bolt in this location was loose. When I pulled it all off, it looks like it had been that way for a while, as that whole area had rust in it. The exhaust riser gasket was still working properly, as I saw no leakage at all from that location.

I guess I am confused. I thought for sure that there was water flow in the exhaust manifold to help cool the exhaust gas, as well as supply water to my dripless shaft seal (as there is a line connected to the hose barB off the port side exhaust manifold). I am confused if there is no water flow in the exhaust manifold how the water gets into the muffler, and then out thru the exhaust flappers...

Regardless, I did have success to the most of my knowledge with the gasket. I torqued the bolts all to approx. 18-ftlbs, and didn't see one leak on the two days I was out this weekend (though I didn't check it often). However, I did notice that the bolts on the exhaust manifold did work themselves loose a bit, so I re-torqued them. I'll make sure to re-check these bolts after each time out.

squeeg333
07-05-2011, 04:55 PM
Okay Larry, sorry man, I see how there isn't water passage inside the manifold. It's got a water jacket - that coupled with the water jacket in the riser mix the gas and water at the end of the riser. Roger that. So, yeh, sounds like I had an leaky exhaust riser gasket. I did replace that in with the work I was doing, so, hopefully that fixed my issue. Sounds like leakage from the maifold/engine mating surface should be VERY rare.

I guess a question I would have is then the exhaust riser gasket - is there a way to know it's leaking on the inside?? I would worry that you wouldn't know until the engine hydrolocked or something very un-fun like that!