Hey, I have just bought a new (used) 351m engine, to replace my old 351m, out of my '79 bronco. The old engine is out, as well as the front clip. I have a couple questions. First should I use loc-tite on the flexplate or torque converter bolts? Do I need to torque any of those bolts? What is the easiest way to align the engine and transmission, so the torque converter bolts line up with the flex plate? Any other tips or tricks would be GREATLY appreciated.
Thank You!!

 

Pulling the front clip is a great idea. @ bottom core support bolts sucked I bet, sawzall them?

Have a way (floor jack) to lift the trams back up, from its saging down position.

If the manual say tighten to x inch or ft lbs do it! Do you want to take it all out down the road for a loose bolt? Lock tight is a good thing.

 

#1... Yes, red Loctite on the flex plate bolts. I don't use Loctite on the torque converter. ALWAYS torque to specs. Make sure the converter is pre-lubed and fully seated on the trans' input shaft.

#2... The hardest part is aligning the trans to the block. Saw the heads off some identical thread mounting bolts and use them as alignment dowels. In terms of alignment, eyeballing works pretty well but ya can always turn the crank pulley bolt to line 'em up.

 

Thanks for the response, I'm just trying to figure out, what are those rubber mounts called that the front clip/ body sit on,and where could I buy them?
Thanks!!

 

Cab-to-body bushings, core support bushings. Sometimes they're called cab mounts, core support mounts. IIRC, some offer polyurethane bushings.

Visit the Tech Thread Sticky and go to the last post for a general list of vendors like NPD, DC, Mac's, LMC, etc.....

 

Ok thanks, I got one more question, the rear main seal, is it something you can see/ replace from the outside of the engine? Or do you have to take apart the engine? I ask this because I bought this engine used and don't see anything around the crankshaft that looks like a seal, so I want to make sure I have one LOL. If they are internal then I'm sure I got one

 

The donor engine hasn't been installed, right? If so, put it on a stand and roll 'er over and remove the oil pan. The rear main seal has two parts.. an upper and lower. The upper is the tough one to replace cuz the crank either has to come out or at least loosened enough to R & R.

I recommend removing the crank. But before doing so mark all the main caps and bearing shells and make sure they go back in the same position. R &R the rear main seals.. off-set it at the block parting line by about 1/8-inch and put a light smear of RTV on the cap mating surface and a small dab at the end of each seal. Wait for about 15 minutes to let it outgas before installing the rear main cap. Reinstall the bearings and caps. Follow the tech manual for the reciprocating assembly.

 

How sure are you of this "used" engine's other internals?

If you're going to do as HIO suggested and loosen/pull the crank, definitely check those main berrins for wear. Pull one from a cap and check it for stock or oversize thickness. Wouldn't hurt to check the rods, too. Good info on offsetting the rear main seal. The lip goes toward the front, by the way.

Check the timing chain for wear while you're there. If you're happy with the lower end, flip it over, pull a valve cover, a couple rockers and pushrods and pull a couple lifters. #1,2 and 5,6 are the easiest. Check those lifter feet for being concave or convex. That'll tell you the condition of the cam.

Check the rockers/valve stems for wear.....pushrod tips for wear/straightness.

Just some ideas...like a gasket set, too....hate to see you "git 'er done" only to have to pull something after 100 miles.

 

Thanks for the response, I'll give those things some thought, I'm in the process of getting some parts together, what would I use for exhaust manifold bolts or are they studs? Where would I buy them? Can I use normal bolts? Thanks for the help!
Brady

 

Exhaust manifolds mount with bolts, normal parts store should sale them.

Use grade 8 bolts and get some good "disk lock" lock washers.

And use lots of anti-seize on them bolts.