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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Gary LaBombard on June 13, 2017, 09:45:54 AM

Title: 8V71 ENGINE CRADLE SUPPORT
Post by: Gary LaBombard on June 13, 2017, 09:45:54 AM
Hey guys,
Need information on the need to replace the cradle support directly under my 1973 05 Eagle engine / Tranny connection.  I had to cut mine out years ago because of rust of coarse and now my engine is back in the frame but I want to know the real function of this support under the engine / tranny area and if I need to reconstruct a new one?  This is about 3-4 inches square tubing that may be intended in case of a engine / tranny separation on the road??  I am not sure but look forward to information from those that have rebuilt their engine compartment on their Eagle as to what they did?

I enclosing a photo that is as good as I can get at this time to help you see the area I am talking about. 
Thanks ahead of time for information.   
Title: Re: 8V71 ENGINE CRADLE SUPPORT
Post by: Scott & Heather on June 13, 2017, 03:21:25 PM
Someone help Gary out :)


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Title: Re: 8V71 ENGINE CRADLE SUPPORT
Post by: luvrbus on June 13, 2017, 06:01:55 PM
Gary, it needs to be there when I cut one out I build it so you can unbolt the cross member in case you need to remove the transmission JMW   
Title: Re: 8V71 ENGINE CRADLE SUPPORT
Post by: Gary LaBombard on June 13, 2017, 06:26:24 PM
OK Cliff, if anyone knows it would be you.  Is the reason for it in the first place as an added support in case the motor mount fails or what?  I will plan on building it such as you did to remove in case needed, so now I have another operation to invent!!  Oh well. Thanks again Cliff & Scott.
Title: Re: 8V71 ENGINE CRADLE SUPPORT
Post by: Gary LaBombard on July 28, 2017, 06:26:48 AM
Well I did as Cliff had suggested and made a heavy duty bracket connecting the engine rail of the driver and passenger side of the engine compartment.  I made the support bracket out of 2 1/2" X 1/4" thick angle iron that I seal welded together and capped both ends.  I also bolted it under the framing so it is removeable also as cliff suggested.  It was a bear to do alone but this entire conversion has been.  Now the bell housing is protected from getting damaged.  Here is a couple of finished photos.  Thanks Cliff for help.
Title: Re: 8V71 ENGINE CRADLE SUPPORT
Post by: Oonrahnjay on July 28, 2017, 09:32:39 AM
Quote from: Gary LaBombard on July 28, 2017, 06:26:48 AMWell I did as Cliff had suggested and made a heavy duty bracket ...

      Looks like a great job, Gary - should be very solid.
Title: Re: 8V71 ENGINE CRADLE SUPPORT
Post by: bevans6 on July 28, 2017, 11:39:07 AM
That support has nothing to do with keep the engine in place, and everything to do with chassis strength.  The chassis is very open there, with the big empty hole to put the engine in to, and the chassis will twist and flex.  That support keeps the chassis tied together, keeps it from racking diagonally and twisting lengthwise.  My MCI 5C has a similar cross beam just under the tail of the transmission, and it is critical.  Earlier MCI MC-5's either didn't have it or lost it and are prone to chassis cracking and failure as a result.  I would look at your repair piece again, from the point of view that it needs to prevent said racking and twisting, and not support anything vertically.  Triangulating the hole would be better but the engine is in the way.

Brian
Title: Re: 8V71 ENGINE CRADLE SUPPORT
Post by: Gary LaBombard on July 28, 2017, 06:04:34 PM
Brian,
I called Frankie Goodson before doing this project to find out reason for this support, he said he seen many eagles with and without the support as original designed by mfg.  He said he thought it was really there to assist protecting the bellhousing from damage from road debris etc.  Your theory sound correct as well, I think and hope I have mounted mine so that it still has control of the twisting as you stated could happen, I am not doing that job again I can tell you.  I am too old to keep getting under that dam bus any more.  Thanks for extra input.