Re-attaching cylinder head

Mafioso812

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OK, so I have installed all of my new parts(1970 model 7260). Now I have a new exhaust gasket, and flange. So what's the trick to getting all the pieces in the correct order, to where the head will align with the bolts? I have learned a whole new language trying this!
 

Mafioso812

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It's where the exhaust is fed through the mower deck.
 

Russ2251

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Engine exhaust port self aligns with hole in deck which in turn aligns with muffler hole.
Can only fit one way.
There are no bolts for head to align with.
 

Lawnboy77

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I'm kinda assuming that you don't have access to the Toro manual that includes mounting the muffler plate and engine for your D-400, so I'll just give you the instructions without pics and hope you can benefit from it. I just remembered that the link I posted doesn't really cover much in relation to mounting the engine of the D-400s with the cast mufflers. You can still buy paperback manuals that cover that, but I'll just summarize those instructions here and inject some of the things I do that the manual doesn't really cover.

The muffler plate, which is what the engine crankcase mounts to with those 3 bolts and locking nuts, will get torqued to the deck first (142 to 170 in.lbs.) If the nylok material is ineffective, or worn out, be sure and use some thread locker, or better yet, get some new locking nuts. The exhaust protrusion of the muffler plate, the cone that mates to the cylinder head will be positioned to the right, and up, as you are standing behind the mower deck (3 oclock position as you are standing behind the deck and looking straight down at the deck). Once the muffler plate is torqued to the deck you can put the new exhaust gasket (gray rubber oval) over the exhaust flange, the small lip at the top of the cone should hold the new gasket in place just fine. Then place the little new stainless steel gasket flange you bought over the gasket and push it down into the opening (lip side down) the lip of little stainless steel flange should go inside the gasket opening and will be fit snug in the plate opening, especially when the engine is torqued to specs, and now you can carefully lower the engine down on the muffler plate and deck while paying particular attention that the cylinder jug and exhaust ports go directly over the exhaust gasket and flange. At this point it is my preference that the mower deck be on wooden blocks so that while the engine is setting on the muffler plate and deck I can install the three engine mounting bolts with one hand holding backup to the bolt heads and the other hand underneath torquing the nuts. Those 3 engine mounting nuts will get torqued to the same torque of 142 to 170 in.lbs. (same rules apply with the locking nuts, if defective, replace or use a thread locker) Tighten those 3 bolts/nuts evenly to compress the new gasket and to prevent snapping a mounting ear off the crankcase. After the engine is torqued you are now ready for those two small square head muffler mounting bolts used to secure the lower half of the muffler. Put those two square head bolts in from the top and place the muffler lower half in place with a serviceable rope gasket in the muffler groove up against the muffler plate. Normally those old rope gaskets will be fine to reuse indefinitely as long as you haven't ruined it by putting it in the parts washer, or disturbed it in anyway. If you don't know what I'm referring to then that's probably a good sign that you haven't removed, or disturbed the old gasket at all, and if that is the case, just press on with pride and you will be just fine without replacing it. Those two muffler nuts will get torqued to 58 to 62 in.lbs. Those lock nuts are subjected to high temps so don't use thread locker, or nylock type nuts. Lawnboy calls those Conelok nuts, but the local hardware store will have what you need in an all metal locking nut, just tell them you need lock nuts subjected to high temps.

Okay hope this helps. When you get her all done be sure and post some pics. I love those old D-400s, they have always been my favorite of all the Lawnboys I have used.
 
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Mafioso812

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Wow! This really helps me out a lot. This is my first venture, in our old Lawn Boy. It was always dependable, and started on the first, or second pull. Thank you for the very in depth instructions. Especially the torquing info. I'm really glad that I found this website, as it has been very helpful, since so many pro's monitor our questions with valuable info. Thanks again.
 
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