Flywheel ring gear diameter issue

[bevans6]

Ring gear diameter issue on my new flex plate.  I ordered the part number that was on the specification sheet for DD 8V-71 engines.  It has a ring gear OD of 19.75".  The flywheel I took off has a OD of 17.25".  I strongly suspect my $1000 ring gear is a boat anchor as far as this project is concerned.  Any words of wisdom?  Does a bus engine with an SAE 1 bellhousing take a different size ring gear than some other engine bell housing?

Brian

[Oonrahnjay]

    Wow, 2 1/2"  is a lot.  Hope it's the right part (or there is some other way to work it out).

[chessie4905]

https://www.powerlinecomponents.com/catalog/page.html?showpage=13&section=2&gclid=CJWAuJ3KwtACFUlLDQodRq8LOg

[bevans6]

Chessie, what am I supposed to look at on that page?  I appreciate the link, I think I will probably call them and ask for advice on Monday.

[luvrbus]

With the drop ring as you know you are going from a SAE 1 bell housing to a SAE 2 bell housing and the flex plates are different and shouldn't be hard to find.The starter location on a MCI bell housing mandates the 17 inch smaller flex plate, on a Eagle with a 8v71 SAE 1 bell housing installing a 647 it would take the 19-3/4 inch flex plate because of the starter location, make any sense    

[jmblake]

Brian, the flex plate I got is 17" if that would help you but I don't have the flywheel/ring gear any more. Jason

[bevans6]

Jason, I think the flex plate you have is for a 740.  The one I need has a ring gear welded on the outside of it.  I am very afraid I won't find one.  If anyone can check their usual good sources for me, I would be very grateful.  If anyone has a contact at Allison direct that I could call, that would also be wonderful.

Brian

[luvrbus]

Have you tried Bobby @ Global in Tucson @520-295-1392 or WW Williams

[bevans6]

Yes, I talked to Bobby, he had nothing that would help.  I don't know anyone at WW williams, and there are a lot of them, do you have a guy or a favorite for the old stuff?

Brian

[luvrbus]

Talk to Bill at WW Williams in Phoenix hurry because he is getting ready to retire

[bevans6]

Hopefully not today!  I will try today but he is probably off, so I will try again on Monday.  Happy Black Friday, BTW - that's a national holiday now isn't it?   

Brian

[daddysgirl]

Thanks for the link Chessie! I'll be using that, I'm sure.
Clifford...I actually understand exactly what you mean. I'm sure Brian has a different set up than I do, but in the old DD engine manual page 7 (not the MCI book) there is a page devoted to various applications, based in part on starter location.

You all are teaching me things I never thought I would need to know

[luvrbus]

That is reason you use a spacer or the offset drop ring on a MCI so the starter clears,you don't use the spacer or offset ring on a 8v71 with a 647 when installing in a Eagle it clears

[daddysgirl]

Brian,
You can try Western Branch Diesel: 703-569-5650 in Springfield,  or 757-673-7000 in Portsmouth, corporate hq.

[luvrbus]

Brian, speak to George at WW Williams not Bill sorry about that