Torque specs for the exhaust

[1970Thunderbird]

Hey all,

I can't seem to find these torque specs, mainly because I'm exactly sure what this piece is called. It's on the exhaust side, beneath the exhaust cover plate. I believe it's a deflector of some kind, and also a cover for part of the cooling system, perhaps.

It's on a 1978 Mercury 800 inline four.

I don't want to under or over tighten the bolts. If you could point me in the right direction, I'd be grateful.

Here are some pics that might help. It's the item sitting on top of the new green gasket. There are about a dozen bolts and I need the torque specs. Thanks!

 

[Texasmark]

Re: Torque specs for the exhaust

You can look up ASME torque specs for different sized/grade bolts on the www search engine. Measure your bolt and that would be your max torque. Buttttt keep in mind it is screwing into cast aluminum with no helical coil to protect from strip-out and it is very soft and easily stripped. BTDT The torque spec is to keep you from twisting the bolt in two, with no reference to the attaching medium.

I would use a sealer, like blue silicon and coat the sealing surfaces regardless of what everyone else says about dry gasket installations. Then snug up all bolts and in a criss cross pattern, slowly go through the pattern several times getting them tighter each time and on the final round, best way I can say it is take a short wrench (6" box) [you are probably going to be using a 7/16 (1/4" stud) to 1/2" (5/16" stud)] and grasp it (the wrench) in the palm of one hand and turn until you feel serious resistance. Give the glue 24 hrs to setup and forget about it.....go about our business.......that's what I would do in a heartbeat and have done and never had to fix a strip or fix a leak.

HTH,

Mark

 

[MercMan82]

Re: Torque specs for the exhaust

That's the water jacket. That's why mine is leaking cause I was afraid of stripping the aluminum.

 

[Texasmark]

Re: Torque specs for the exhaust

That's the water jacket. That's why mine is leaking cause I was afraid of stripping the aluminum.

That's why I put mine on wet and the glue covers all those tiny holes that the water would otherwise flow past, especially on an older engine with the obvious corrosion/pitting that occurs in these areas.

Mark

 

[1970Thunderbird]

Re: Torque specs for the exhaust

MercMan,

We have a die grinder at work with a special pad we use to remove old gaskets. Use it all the time on pumps. I used that and got shiny aluminum. I hope yours turns out alright.

 

[Texasmark]

Re: Torque specs for the exhaust

Oh, and one more thing: Wire brush the bolt threads clean and use a anti-sieze material on them. "Blue" Locktite (auto parts store) is perfect....blue prevents bolts from freezing and locks them so that they won't back out....comes out easily if bolt has to be undone. Other colors are for other uses. Used it in industry for 10's of years.

Mark

 

[MercMan82]

Re: Torque specs for the exhaust

Yeah I know the one. I used a hone stone and got the same result. I think my gasket sealer is what is giving me trouble. It never hardened up and is still kinda wet.

 

[Texasmark]

Re: Torque specs for the exhaust

Yeah I know the one. I used a hone stone and got the same result. I think my gasket sealer is what is giving me trouble. It never hardened up and is still kinda wet.

Blue RTV works great, especially the kind that seems to be fibered...has little white streaks in it...auto parts store....may be the Lubriplate brand...silver (unpainted alum) tube as I recall. It stays slightly pliable so it doesn't crack, has a very high adhesion capability, is designed for water passages and is temperature resistant. After you install it, give it 24 hours or so to harden up and let it air cure for 5 roughly minutes before you assemble the parts.

 

[1970Thunderbird]

Re: Torque specs for the exhaust

That's why I put mine on wet and the glue covers all those tiny holes that the water would otherwise flow past, especially on an older engine with the obvious corrosion/pitting that occurs in these areas.

Mark

When you say put on "wet," do you mean with RTV, or actually wetting the gasket?

 

[merc850]

Re: Torque specs for the exhaust

Here's the manual way
and the tork specs: cover-250 in/lbs - water jacket 150 in/lbs.

 

[Texasmark]

Re: Torque specs for the exhaust

When you say put on "wet," do you mean with RTV, or actually wetting the gasket?

RTV.. wet means using an adhesive vs a dry gasket only.

 

[Texasmark]

Re: Torque specs for the exhaust

Here's the manual wayView attachment 120291
and the tork specs: cover-250 in/lbs - water jacket 150 in/lbs.

250 in lbs/12 = 21ft-lbs and 150 = 13. (I'm used to ft-lbs and that's what my wrenches are.) Sounds good to me. You're not going to tear up anything with clean threads, Locktite and some RTV with those numbers. Torque specs are for clean, non-binding threads meaning you are measuring the pressure on the covers, not the pressure it takes to screw the screw and you'll be able to do just that.

Mark