Right bank issue

Geoff · October 16, 2016, 06:42:18 PM

With all the time taken reading as well as typing all the posts in this thread I could of had the head and blower off and know the answer.

--Geoff

dtcerrato · October 16, 2016, 09:38:03 PM

In that order, right? OK, I hear ya. We're pulling it tomorrow...

dtcerrato · October 16, 2016, 09:46:27 PM

"blower clearance close up as they wear" - Makes sense. Our blower disintegration was caused by a failed bearing housing. That would be an instantaneous lack of clearance! Even prior to housing failure, a worn bearing would create inconsistent clearance between the lobe & case.

luvrbus · October 17, 2016, 07:32:33 AM

The ports are at the top of the block not on the same level as the blower that pressurizes the air box from the bottom.I have taken bits of rings and liners from a engine that have laid in the air box for 25 years.DD built the blower from aluminum for a reason.If the blower had damaged the engine it wouldn't have waited 7000 or 8000 miles to show signs and a blower has nothing to do with setting he has posted IMO,and I know if you don't have the bridges set right it is going to take a valve out so will a injector tip

Scott Crosby · October 18, 2016, 12:31:33 AM

Valve clearances were good all except 1. One valve is slightly bent from closing on a piece of debris. Two pistons have impact damage and they are not next to each other. The head has a few dings but surprisingly looks nothing like the pistons. The liners are worn out with a very noticeable wear can be felt at the top of the liners. The really bad liner is toast but all others were still firing but worn out.

luvrbus · October 18, 2016, 04:59:09 AM

Scott,the spacing and everything is so round an uniform it looks like a old trunk style piston that separated above the fire ring,they moved the fire ring down on the later trunk pistons you will know for sure when you remove it,probably bent the rod too and i don't believe the blower caused that damage

eagle19952 · October 18, 2016, 09:18:53 AM

Quote from: luvrbus on October 18, 2016, 04:59:09 AM
Scott,the spacing and everything is so round an uniform it looks like a old trunk style piston that separated above the fire ring,they moved the fire ring down on the later trunk pistons you will know for sure when you remove it,probably bent the rod too and i don't believe the blower caused that damage

nope...looks like overspeed to me.

dtcerrato · October 18, 2016, 10:08:05 AM

When the head was replaced we mentioned a liner kit but figured the ole' girl had one more good run in her, & it did. I think the blower shrapnel that went through the engine was the fuse to have more things happen. When we cleaned out the air box prior to blower replacement, we were pulling blower shrapnel off of the liner ports (literally) that were too big to go through. We know there was at least more than a minute of full speed run after blower failure so what went through had already happened... My 2 cent anyhoo...
My bad on posting inaccurate clearances - that kind of stuff happens when a carpenter gets a set of feeler gauges in his hands!
Overspeed is always on the table with our standard shift & no jakes. On downhill runs it stays in gear with intermittent braking to control speed.

eagle19952 · October 18, 2016, 10:19:08 AM

Quote from: dtcerrato on October 18, 2016, 10:08:05 AM

Overspeed is always on the table with our standard shift & no jakes. On downhill runs it stays in gear with intermittent braking to control speed.

Shrapnel complicated overspeed... a new diagnostic code is born

lostagain · October 18, 2016, 05:50:05 PM

Over speed should not be on the table, ever. Do not let the engine go over 2200, 2300 rpm.

JC

dtcerrato · October 20, 2016, 03:09:22 PM

Head is in the machine shop & planning on an in-frame rebuild. Its been a tired engine for quite some time now - doesn't owe us a thing, we will continue to keep it alive.

Brian Diehl · October 23, 2016, 01:36:13 PM

Hey - that is great Dan. Glad to know you are keeping your bus going! I'm sure you'll be very pleased once it is all back together and running like a top again! Keep up the good work.

chessie4905 · October 23, 2016, 05:26:03 PM

Have them check spring opening and closing pressures.I would replace all the valves but that's just me.

dtcerrato · October 25, 2016, 08:32:15 PM

Would like some feedback/opinions on High Zink break in oil & assembly lube & Engine Run-In Schedule as stated in da book (In Line Diesel Engine Series 71 Maintenance Manual). Thanks

luvrbus · October 26, 2016, 06:16:19 AM

They did away with the hi zinc oil when the silver was removed from the bearings and in the later book you assemble with engine oil mixed with STP your manual will have those pages replaced (like 140) if the little cards were sent in to Detroit.

Assembly grease is still good sometimes I use the Lubricate 105 if I know the engine is going to set for a long period of time before the install