The condision of the chain. At this point in the life cycle of the 403/455. IS NOT the problem. So. The cam will be running a few degrees retarded. There isn't one of us that would ever pick this up the performance loss from our engine. Even if you get 200,000 miles on it. And the chain jumps a tooth. That WILL NOT destroy that engine. It will still get you home. The BIG problem is the aging of the plastic teeth that are on the cam sprocket. Plastic cracks with age. Not miles. A failed cam gear WILL DISTROY you engine. PIRIOD. Every engine will be running perfectly just before that sprocket fails. Here's the two choices. A $60 sprocket/chain replaced while at home. Or a complete engine rebuild somewhere on the road. It can be checked out with an inspection camera. By removing the engine fuel pump Bob Dunahugh
Engine Timing Chain Test.
- Thread starter Bob Dunahugh
- Start date
No they aren’t. That is usually an engine that when it loses the drive belt to the camshaft it allows the valves to drip and punch holes in the pistons. That doesn’t happen with the Olds 455 or 403. Youusually worry about that on small import engines.
Emery Stora
>
> Are these engines an interference design?
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Emery Stora
>
> Are these engines an interference design?
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
That is not a usual concern with the Olds. It can happen if a "long
timed-high lift" camshaft is substituted for factory stuff. The real hazard
to navigation is the plastic pieces circulating inside the engine. Bad
stuff happens as a result.
Jim Hupy
Salem, Or
On Sun, May 19, 2019, 9:39 AM Emery Stora via Gmclist <
> No they aren’t. That is usually an engine that when it loses the drive
> belt to the camshaft it allows the valves to drip and punch holes in the
> pistons. That doesn’t happen with the Olds 455 or 403. Youusually worry
> about that on small import engines.
>
> Emery Stora
>
> > On May 19, 2019, at 11:04 AM, Johnny Bridges via Gmclist <
> >
> > Are these engines an interference design?
> >
> > --johnny
> > --
> > Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> > Braselton, Ga.
> > I forgive them all, save those who hurt the dogs. They must answer to
> me in hell
> >
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
timed-high lift" camshaft is substituted for factory stuff. The real hazard
to navigation is the plastic pieces circulating inside the engine. Bad
stuff happens as a result.
Jim Hupy
Salem, Or
On Sun, May 19, 2019, 9:39 AM Emery Stora via Gmclist <
> No they aren’t. That is usually an engine that when it loses the drive
> belt to the camshaft it allows the valves to drip and punch holes in the
> pistons. That doesn’t happen with the Olds 455 or 403. Youusually worry
> about that on small import engines.
>
> Emery Stora
>
> > On May 19, 2019, at 11:04 AM, Johnny Bridges via Gmclist <
> >
> > Are these engines an interference design?
> >
> > --johnny
> > --
> > Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> > Braselton, Ga.
> > I forgive them all, save those who hurt the dogs. They must answer to
> me in hell
> >
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
Thanks Emery. I didn't think it was but I wanted to know. It ought to survive a busted timing chain then. Ford's first cammer for the Escort and
the VW Diesels are interference engines. Ask me how I know this
Matterofact, so's the VW gas one of the same size.
--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
the VW Diesels are interference engines. Ask me how I know this
Matterofact, so's the VW gas one of the same size.--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
Problem is if it still runs skipped a tooth your retarded timing will turn fuel to heat not usable cylinder pressure and you will cook the engine.
--
John Lebetski
Woodstock, IL
77 Eleganza II
--
John Lebetski
Woodstock, IL
77 Eleganza II
The plastic can also plug the oil pump pick up filter and cause low oil pressure. After
shutting down the motor the plastic pieces will drop down into the pan and you will
have higher oil pressure again. I have had this happed to a Chevy small block.
Just something else to watch out for.
The fun of owning a GMC never stops!!
Jim Wagner
Brook Park, oh
1976 GMC500
1971 Vega355
1969 Vette383
shutting down the motor the plastic pieces will drop down into the pan and you will
have higher oil pressure again. I have had this happed to a Chevy small block.
Just something else to watch out for.
The fun of owning a GMC never stops!!
Jim Wagner
Brook Park, oh
1976 GMC500
1971 Vega355
1969 Vette383
