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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Fredward on May 06, 2014, 07:13:29 AM

Title: Another 871 Oil Leak
Post by: Fredward on May 06, 2014, 07:13:29 AM
I thought I had a leaking main seal, but upon closer inspection, It looks like one of the three bolts in the upper right  hand section of this photo is leaking. Can i just remove the bolts, put new brass or copper washers on them, add a little RTV and re-install? Or will something fall off inside the engine? Are these bolts plugging the oil galleys? (https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fimg.tapatalk.com%2Fd%2F14%2F05%2F06%2Fuha5u6yg.jpg&hash=c888677b63b482815152f59d00ae4c0207133241)


Fredward
Title: Re: Another 871 Oil Leak
Post by: Utahclaimjumper on May 06, 2014, 08:42:42 AM
Remove, clean, install copper rings and retorque.  For gods sake don't use RTV on the threads.>>>Dan (You don't want RTV any where near oil passages)
Title: Re: Another 871 Oil Leak
Post by: luvrbus on May 06, 2014, 08:51:34 AM
Fred only the counter sunk bolts use copper washers get those from DD they are thick, the others use a grade 8 flat washer no lock washers should be any where,the big bolt in the housing under the starter holds a drive gear on.The only pressure galley is the one at the top for the blower the rest are just low pressure return paths one on each side, replace the rear seal while you are there best 25 bucks you will ever spend

good luck
Title: Re: Another 871 Oil Leak
Post by: bevans6 on May 06, 2014, 10:16:09 AM
Copper washers work-harden the first time they are torqued down on, and don't seal as well the second time.  You can heat them with a propane torch and anneal them if they aren't squished out of shape and you don't have new ones.

Brian
Title: Re: Another 871 Oil Leak
Post by: Scott Crosby on May 06, 2014, 01:12:14 PM
I'm replacing my seal this week.  My seal is not leaking but some of the gaskets were. I'm replacing every gasket and seal on it down to the block end on this side too.   This is the only seal that I have come across that was not leaking on the whole engine. 

(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fimg.tapatalk.com%2Fd%2F14%2F05%2F07%2Faja4a2u3.jpg&hash=5d2732b09d6e95c081c2e2d8bf1e2a75ed6db112)
Title: Re: Another 871 Oil Leak
Post by: Fredward on May 06, 2014, 07:43:30 PM
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fimg.tapatalk.com%2Fd%2F14%2F05%2F07%2Fzeqypade.jpg&hash=e4d2b89c2584a4a9e4dc1da2927e44912d039f09) I removed the bolt and it had what appears to be a steel washer that is too big for the recess that it needs to seat into. As soon as the bolt was out, oil started drooling out of that hole. The bolt head is 9/16". What size washer do I need?


Fredward
Title: Re: Another 871 Oil Leak
Post by: luvrbus on May 06, 2014, 07:50:33 PM
3/8th those washers sometimes are hard to find I don't even look I order those from DD but I'll check I may have some new ones I'll put in your package
Title: Re: Another 871 Oil Leak
Post by: Fredward on May 06, 2014, 07:52:54 PM
Thanks Clifford, I can also run to Interstate Diesel if you don't have.
Scott, where's your starter?


Fredward
Title: Re: Another 871 Oil Leak
Post by: Scott Crosby on May 07, 2014, 02:22:06 AM
My starter is at 2 o'clock position. The angle doesn't let you see the hole, but you can see the bulge for the mount.   The gm sits at an angle so my rear head is level and the whole engine sits tipped out at about a 45.  My accessory drive housing is a different shape because it does the mounting and tipping angle for the GM.   My flywheel is also sealed in and wet with auto trans fluid tied into the V730.   A leakey main seal would not be detectable by a drip on the ground on mine.  It's a little different 8v71 besides just turning the other direction. From the block out is where it really starts to get much more different.  I didn't even clean it, that's how clean the trans fluid keeps it looking.  On my other engine I had a trans fluid leak from my starter when I first got the bus. That's how I learned the flywheel on the automatics are in trans fluid.   I remember thinking how on earth is trans fluid leaking 10" away from my transmission and also above it?  

Title: Re: Another 871 Oil Leak
Post by: bevans6 on May 07, 2014, 02:39:53 AM
If there is an airport or aircraft supply place near you, the crush washer for an AN-3 fitting will fit perfectly, they are 3/8".

Brian