Desert Flywheel

[Lil StompeR]

OK, We have an 84' Bronco 351 C6 and it won't start? I've been told it's a flywheel?

Not so fast, the starter and battery has been changed!

Now what? Was I told right? Or is it something else? and how easy is it to change the fly wheel, it's been awhile since I've done it!

Drop the Tranny, off with the old Flywheel and on with the new? like 1,2,3 ?

any advice?

 

[Bronc76]

Will the motor turn over or wont? If it turns over, are you getting spark? try jumping the solenoid to see if thats the problem.

 

[Broncobill78]

Just what is it doing when you try to start it ? If it cranks ok but you're getting a loud crashing/grinding sound when you do then the starter probably isn't meshing with the flywheel. If this happens enough times the teeth on the flywheel become damaged. It usually starts with a "bad" spot on the flywheel that causes it to grind when you try to start it but try it two or three times and the flywheel moves a bit and you get past the bad spot & are able to start it. Eventually though the whole ring-gear/flywheel gets chewed up and at that point the only thing left to do is replace it.

To replace it drop the tranny & torque converter, unbolt the bad flywheel & replace it with a new one and be off on your merry way.

Before jumping into this though could you tell us a little more about just it's doing when you try to start it ?

 

[madmax]

If the starter tries to turn over and you just hear it spinning (as if it's attached to nothing) or you hear it grind, yank out the starter and get a big regular head screwdriver and pry on the gear around the flywheel to turn it to a good spot on the gear. reinstall the starter and try starting it again.

Also, with a jumper cable and a ***** driver you can manually fire off the starter, jumper to the hot side, other end of jumper to a ***** driver you don't care about and push it to where the heavy cable attaches, that should fire it off. One more thing, sometimes when changing the starter people forget to clean off the crud before putting the new one in, depriving the motor of a good ground connection.

 

[Broncobill78]

Some of those starters also have a spacer that goes in there so that the starter gear meshes properly when the throw-out engages. Without the spacer the depth is wrong & it'll grind on the ring-gear which may have been what created the problem in the first place & when you just now replaced the starter the spacer wasn't there so the problem is being compounded. Just a thought.

Try rotating the engine by hand (by grabbing the belts or pulleys) and see if spinning the flywheel a bit helps. Last year I had to replace the flywheel in my 88' because the inner bolt circle (holding it to the crank) had sheared completely leaving me with a 2-piece flywheel. It would grind badly & simply wouldn't start. The flywheel was always out of position because the outside part with the ring-gear was spinning on the inner so even when the starter DID actually engage properly it would simply spin the ring-gear around without rotating the crank. I'm not suggesting this is your problem but it's certainly *possible*. I didn't figure it out until I dropped the tranny to replace the flywheel (because I thought the ring-gear teeth were the problem), the link to that post is below. Again, it would help to know more about exactly what it's doing when you try to start it & if you're able to get anywhere by rotating the engine by hand.

http://broncozone.com/forums/index.php?sho...broken+flywheel

 

[madmax]

oh yea, i remember that, i wanted that as a wallhanger, and i was going to send you my extra flywheel, but if lil stomper could use it, well it's all his. I don't know if you can use a 1991 351 flywheel on a 1984 351 off hand. also, broncobill, if he dosn't need it to get his truck back up and running, you can still have it if you want.

 

[Lil StompeR]

Finally got around to testing my brake lines that I've installed into the 84 Bronco. Some I made myself, others are pre-made legnths from O-reilly's Auto Parts. I bench-bled the master cylinder, and let gravity flow take the fluid down the lines as much as possible before try to bleed the system. No leaks at all four wheels, but some of the tee-fittings and unions leaked like mad. How tight should the connections be? I snugged them all up beforehand, but not past the point where the nut felt like it stopped, maybe 10 ft-lbs max. The two lines I custom-made appear to have a low-quality double flare as compared to the pre-made lines, so I plan to replace them with the pre-made. But two of the connections on the pre-made also leaked . Any suggestions for better quality hard lines? Or should I invest in some more braided steel flex hoses? I have two of those, one for each axle drop. JSM84

Thanks everyone, I'll give it a shot.

and thanks for the offer on the flywheel that's great, their are still some decent people out there! I've forgotten, I've been in So. Cal. too long, 8 yrs. too long!

Thanks, and I'll keep you posted!

and I picked up one for cheap!

 

[Yardape]

I would definately look into it a bit further before yanking the tranny out in the middle of nowhere. I would remove the inspection cover at the bottom of the bellhousing, have someone turn the engine over by hand while you inspect the teeth of the flywheel. You will easily be able to see the damage if it is there. Much better than pulling the tranny if you dont have to. If it is damaged but only in a small section you can use Madmax's advise and position the flywheel in the best spot with the best teeth, you migh get lucky and fire it up then you can at least drive it to a better location.

 

[Broncobill78]

Yeah, I was in the hospital for most of last July & while I was in the wife went a little nuts with the cleaning & that flywheel along with a lot of other broken & useless stuff that I wanted got tossed. /emoticons/[email protected] 2x" width="20" height="20" />