Douglas & Virginia Smith
dsmithy18 at gmail
Lincoln Nebraska
’73 “Canyonlands” since ‘95: “Wanabizo”, Anishinabe Indian for “He gets lost driving” Yes, really.
Quadrabag/6 wheel disks/3;70 final/Paterson QuadraJet/Thorley’s/Sundry other
P&W PT6, no wait, that's the wish list...
Unsure on the type of thermostat that you are currently using, but if it is a stock style and not a Robertshaw High Performance type thermostat then you can be creating you own problems as a stock style thermostat does not flow enough coolant and are subject to failure, just ask Jim B.
By Stock thermostat I mean this type:
By Robertshaw High Performance I mean this type:
https://www.gmcrvparts.com/product-p/gm8-006-14-180.htm
https://www.gmcrvparts.com/product-p/gm8-006-14-195.htm
https://www.summitracing.com/parts/mrg-4364
<https://www.jegs.com/webapp/wcs/stores/servlet/SearchResultsPageCmd?Ntt=mrg-4364&requestYear=&storeId=10001&catalogId=10002&langId=-1&year=&make=&model=&submodel=&engine=&Nrpp=&No=&persistYmm=false>
Notice the difference in construction of the units. The stock style unit is limited on the amount of flow that it can pass. The amount of heat that needs to be removed by the coolant requires a higher performance type of thermostat, look at the size radiator that we have for heat rejection. I have included both the 180 and 195 thermostats as GMC owner have run both. I personally have run only the 180 degree unit over the last 19 years as my thoughts that I want to remove as much heat as I can with the 180 deg unit. Some with fuel injection may run the 195 deg unit.
The High Performance type thermostat are available at most auto part store.
I have presented the various information available and the choice is yours to make!
Regards,
J.R. Wright
GMC Great Laker MHC
GMCGL Tech Editor
GMC Eastern States Charter Member
GMCMI
78 GMC Buskirk 29.5’ Stretch
75 GMC Avion (Under Reconstruction)
Michigan
--
Jim Kanomata
Applied/GMC, Newark,CA
ji...@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
Also, they provide just a bit more bolt between the head and the threads.
This is where the bolt stretches elastically under tensioning, and it’s
that elastic strain that keeps them from ever losing tension under load.
Loss of tension is what allows them to back out and get loose, just as with
spokes on a bicycle wheel.
I believe the high tensioning torque is there to cause any internal
stresses to yield and these be relieved. These can be microscopic but can
contribute to fatigue failures. Tensioning close to proof load actually
prevents fatigue in bolts not loaded in tension (except from tightening),
which these are not. The tightest these bolts ever are is just sitting
there after torquing them down. They are loaded in pure shear, but it’s the
clamping friction that carries the load.
So, the lock washer doesn’t work by biting into the bolt, it works by
preventing any loss of tension in use, which keeps the bolts from backing
out.
Rick “all structures are elastic” Denney
--
'73 X-Glacier 230 "Jaws"
Northern Virginia
Offlist email: rick at rickdenney dot com
Engineers often state that bolts are loaded in shear when they mean that
structures are loaded in shear. Any bolted connection that uses holes large
enough not to be an interference fit carry their loads by clamping
friction.
I’m not opposed to Loctite by any means, though I do wonder how that
changes the torque requirements. I am opposed to using Loctite as an excuse
to avoid tightening them to spec, in the false notion that the bolts can’t
take it. I’ve heard of many loosened drive axles, but I’ve never heard of
broken bolts during or after torquing, if they were the proper
high-strength bolts.
Rick “the factory didn’t use Loctite” Denney
--
'73 X-Glacier 230 "Jaws"
Northern Virginia
Offlist email: rick at rickdenney dot com
Les Burt
Montreal
'75 Eleganza 26'
In a couple of weeks there will be a lot of guys (and gals) who have all considered the smoking hole in their foot at a confab in Mansfield, Ohio.
Those who claim they have not are being less than candid.
Remind me to tell you about the first engine I built in three decades…..
Onward! You’ll get it.
Dolph
DE AD0LF
Wheeling, West Virginia
1977 26’ ex-PalmBeach
Howell EFI & EBL, Reaction Arms, Manny Transmission
“The Aluminum and Fiberglass Mistress"