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David Wood's 403 [message #333992] Mon, 25 June 2018 17:31 Go to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

As some of you may remember, Dave Wood overheated his coach on the way to the Tucson GMCMI back in April. He was towed to the KOA where II helped diagnose the initial problem as a heater hose that had been riding on the AC pulley and had worn through.

I sent Dave and his friend out for some supplies and changed out the hose for him only to find that the problem was much worse than just a worn through hose. When we filled it back up with coolant, it was steaming out of the exhaust rather badly and when we removed the radiator cap, there was quite a bit of pressure and air bubbling out of the radiator.

Alex and Miguel were called over only to confirm the diagnoses of a cracked head or blown head gasket. At the end of the rally, the coach was towed to Calypso Automotive where my mechanic friends, Ron & Jim agreed to replace the heads. Unfortunately, the job turned into a much bigger deal than they had anticipated or wanted to do. When Jim pulled the heads off, he found two burned pistons (Holes burned in the top edge of the #4 and #5 pistons)

The engine needed to come out and a complete rebuild needed to be done. The coach is back up and running as of Friday evening,. I test drove it today at Jim's request and it runs great. There are still a few tweaks needed, but ti is back together and I understand Dave will be back in Tucson Wednesday to pick it up, put a hundred or so miles on it, bring it back for another oil change and then drive it back over the mountain home to San Diego.

Attached is a link to a couple of photos I took of the internal damage and the suspected cause of the severity of the problems. There was some kind of snake oil injector(???) in the PVC hose that I noticed was sucking in a LOT of air after I fixed the heater hose. I believe it was causing an overly lean condition in those two cylinders, which combined with the overheating, caused the burned pistons.

http://www.gmcmhphotos.com/photos/g7162-david-wood-27s-403.html

If anyone can identify the "snake oil injector" I would be curious as to what it might be and what it's supposed function was. So far no one that has seen it can identify it.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: David Wood's 403 [message #333994 is a reply to message #333992] Mon, 25 June 2018 18:08 Go to previous messageGo to next message
GMC2000   United States
Messages: 193
Registered: March 2018
Location: Georgia
Karma: -3
Senior Member
thats a very curious looking device.. the pistons appear to have suffered from pre ignition. Im not sure how any device in the PCV line can cause that and specifically on #4 & 5.

does the 403s also have the exhaust crossover in the intake manifold too?
Re: David Wood's 403 [message #333996 is a reply to message #333994] Mon, 25 June 2018 18:53 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

The 403 does have the exhaust crossover (now blocked). Dave didn't report hearing any preignition, but then he is 88 years old. At 62, I'm not sure I can hear preignition any more. I theorize that the vacuum leak contributed to the overheat conditions in those two cylinders due to the overly lean conditions the mystery device caused. Being in the PVC line, it would have affected those two cylinders the most due to where the PCV hose hooks up to the carburetor. (Also, I don't remember if those were the two cylinders those pistons came from, it could have been #2 and #3. Either way, they were opposite each other on the same crank throw.)

Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: David Wood's 403 [message #333999 is a reply to message #333996] Mon, 25 June 2018 20:42 Go to previous messageGo to next message
GMC2000   United States
Messages: 193
Registered: March 2018
Location: Georgia
Karma: -3
Senior Member
I think youre right about that. if it was sucking in air like you said, thats alot of air so thats probably exactly what happened. maybe that was a water injection gizmo where it pulls in water in the small fitting and also mixes the air from the top (with hardly no filtering)

piston got real hot from being lean and it looks like it pre ignited itself at some point (the one with the most damage)

that gizmo is definitely a sinister looking one.
Re: David Wood's 403 [message #334002 is a reply to message #333992] Mon, 25 June 2018 21:10 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
Messages: 2324
Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
Strange. I would of guessed marvel mystery oil injector..... but that does not look quite correct.


https://www.flickr.com/photos/91591049@N00/12435030174


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] David Wood's 403 [message #334004 is a reply to message #333992] Mon, 25 June 2018 21:47 Go to previous messageGo to next message
Jeanette is currently offline  Jeanette   United States
Messages: 118
Registered: May 2013
Karma: 0
Senior Member
Carl I thank you so much for checking out Mr Wood n all you have done with others to get him back on the road again.

Sent from my iPhone

> On Jun 25, 2018, at 5:31 PM, Carl Stouffer wrote:
>
> As some of you may remember, Dave Wood overheated his coach on the way to the Tucson GMCMI back in April. He was towed to the KOA where II helped
> diagnose the initial problem as a heater hose that had been riding on the AC pulley and had worn through.
>
> I sent Dave and his friend out for some supplies and changed out the hose for him only to find that the problem was much worse than just a worn
> through hose. When we filled it back up with coolant, it was steaming out of the exhaust rather badly and when we removed the radiator cap, there was
> quite a bit of pressure and air bubbling out of the radiator.
>
> Alex and Miguel were called over only to confirm the diagnoses of a cracked head or blown head gasket. At the end of the rally, the coach was towed
> to Calypso Automotive where my mechanic friends, Ron & Jim agreed to replace the heads. Unfortunately, the job turned into a much bigger deal than
> they had anticipated or wanted to do. When Jim pulled the heads off, he found two burned pistons (Holes burned in the top edge of the #4 and #5
> pistons)
>
> The engine needed to come out and a complete rebuild needed to be done. The coach is back up and running as of Friday evening,. I test drove it
> today at Jim's request and it runs great. There are still a few tweaks needed, but ti is back together and I understand Dave will be back in Tucson
> Wednesday to pick it up, put a hundred or so miles on it, bring it back for another oil change and then drive it back over the mountain home to San
> Diego.
>
> Attached is a link to a couple of photos I took of the internal damage and the suspected cause of the severity of the problems. There was some kind
> of snake oil injector(???) in the PVC hose that I noticed was sucking in a LOT of air after I fixed the heater hose. I believe it was causing an
> overly lean condition in those two cylinders, which combined with the overheating, caused the burned pistons.
>
> http://www.gmcmhphotos.com/photos/g7162-david-wood-27s-403.html
>
> If anyone can identify the "snake oil injector" I would be curious as to what it might be and what it's supposed function was. So far no one that has
> seen it can identify it.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: David Wood's 403 [message #334005 is a reply to message #334002] Mon, 25 June 2018 21:53 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

lqqkatjon wrote on Mon, 25 June 2018 19:10
Strange. I would of guessed marvel mystery oil injector..... but that does not look quite correct.


https://www.flickr.com/photos/91591049@N00/12435030174



Now THAT would be a good idea!!! Wink


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] David Wood's 403 [message #334006 is a reply to message #334004] Mon, 25 June 2018 21:54 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Jeanette wrote on Mon, 25 June 2018 19:47
Carl I thank you so much for checking out Mr Wood n all you have done with others to get him back on the road again.

Sent from my iPhone

> On Jun 25, 2018, at 5:31 PM, Carl Stouffer wrote:
>
> As some of you may remember, Dave Wood overheated his coach on the way to the Tucson GMCMI back in April. He was towed to the KOA where II helped
> diagnose the initial problem as a heater hose that had been riding on the AC pulley and had worn through.
>
> I sent Dave and his friend out for some supplies and changed out the hose for him only to find that the problem was much worse than just a worn
> through hose. When we filled it back up with coolant, it was steaming out of the exhaust rather badly and when we removed the radiator cap, there was
> quite a bit of pressure and air bubbling out of the radiator.
>
> Alex and Miguel were called over only to confirm the diagnoses of a cracked head or blown head gasket. At the end of the rally, the coach was towed
> to Calypso Automotive where my mechanic friends, Ron & Jim agreed to replace the heads. Unfortunately, the job turned into a much bigger deal than
> they had anticipated or wanted to do. When Jim pulled the heads off, he found two burned pistons (Holes burned in the top edge of the #4 and #5
> pistons)
>
> The engine needed to come out and a complete rebuild needed to be done. The coach is back up and running as of Friday evening,. I test drove it
> today at Jim's request and it runs great. There are still a few tweaks needed, but ti is back together and I understand Dave will be back in Tucson
> Wednesday to pick it up, put a hundred or so miles on it, bring it back for another oil change and then drive it back over the mountain home to San
> Diego.
>
> Attached is a link to a couple of photos I took of the internal damage and the suspected cause of the severity of the problems. There was some kind
> of snake oil injector(???) in the PVC hose that I noticed was sucking in a LOT of air after I fixed the heater hose. I believe it was causing an
> overly lean condition in those two cylinders, which combined with the overheating, caused the burned pistons.
>
> http://www.gmcmhphotos.com/photos/g7162-david-wood-27s-403.html
>
> If anyone can identify the "snake oil injector" I would be curious as to what it might be and what it's supposed function was. So far no one that has
> seen it can identify it.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Hey, it's the GMC way. Wink



Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: David Wood's 403 [message #334019 is a reply to message #333992] Tue, 26 June 2018 07:28 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
I really thought that I had seem most of the snake oil fire vapor injectors, but I haven't seen that one before.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: David Wood's 403 [message #334029 is a reply to message #334019] Tue, 26 June 2018 09:06 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Matt Colie wrote on Tue, 26 June 2018 05:28
I really thought that I had seem most of the snake oil fire vapor injectors, but I haven't seen that one before.

Matt



Yeah, so far nobody else has either. It was creating a tremendous vacuum leak though.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: David Wood's 403 [message #334046 is a reply to message #333996] Tue, 26 June 2018 13:31 Go to previous message
Richard RV   United States
Messages: 631
Registered: July 2012
Location: Full-timer for 12 years, ...
Karma: -17
Senior Member
Excellent news, Carl. Thanks for taking the point position. I know Dave appreciates it. We all do.

Richard


'77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemont waiting its turn
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