6.2 fan upgrade...couple pics.

changed fan clutch today,installed a 7-blade fan while i was in there.

if any one is curious,the fan mounting holes measure thusly (with a measuring tape...not super precise but really close)

mounting hole center to center...2-9/32"
mounting hole center to center diagonal...3-1/4"
fan center bore...2-5/8"

the fan seems to be from an industrial 427 or maybe a 454,but i can't be sure.picked it up of the ground in a scrap yard for 5 bucks.
The only numbers i could find were on the blades...916412 b78...367179.

luckily the new fan clutch is a tad longer,so the flat hub on the fan mounts the whole thing far enough out to clear the pully's and belts by about 1/2 an inch.the old clutch was to short,and the new fan did not have adequate clearance.the old clutch didn't seem to want to engage at all anyway,so it had to go.

how much room between the fan clutch and the oil cooler lines?

lots...

about 3 inches...very close to what it was originally.the fan itself,by the way,is a little further away from the rad.the reason being that the original fan had a hub with a slighty dished mounting surface...this,i think,must have been by design to clear the extra length of the lower pully.

with the new fan/clutch,the clutch moves about 1/2 an inch further forward,while the flat non-dished mounting hub on the fan,moves the fan disk further back...it works out with less clearance for the belts (but still adequate) and slightly more fan clearance from the rad,with the end result that the fan disk ends up about 1/2 an inch further back.

in any event,i took it out for a burn,and there was no hint of any rubbing at all.i could wish for more belt clearance,but it works fine.it really pulls air...the temp swings i'd get,even with a new rad (installed 2 weeks ago),seem to be held in check.as measured on the autometer temp guage (installed 3 weeks ago),which shocked me into fixing my cooling system.

i whish i had taken pics of the old rad.definitely the original.it was so gunked inside,no amount of flushing could help.you really should install a decent temp guage in your cucv's.
should be at the top of the modification list in fact.

RE: lots...

my radiator that i pulled out during the turbo install was the original as well, also shot beyond repair. I had a new 2core aluminium radiator made up, uses 2x 1" cores and should be a little of a cooling capacity upgrade. I am going the route of dual electric fans instead of a engine driven, mainly due to space issues. I have dual 14" fans mounted on a aluminium shroud. they are operated off of a thermostat in the radiator, but I am adding a real temp gauge as well. what was the part# of your gauge? I assume that you got a 2nd threaded port to replace the block-off plate on the passenger rear of the engine? what adapter did you have to use if any?

a temp gauge install would make for a very good tech article for the site.

post later...

will take some pics and post tomorrow.as for the sender,i removed the stock non functioning one from the left front,drivers side head.

didn't know if that sender did anything at all.cut the wire (green,on mine) and everything functioned normally.both hot and cold starts.the new sender that came with the guage,went into the stock location.no trouble at all.in fact it works better...for some reason the high idle solinoid has come back to life.

the oil pressure guage,now,was more fun.i wish i had taken some pics of the get-up i used to reach back there.it involved a forklift a lage pallet and some foam padding.i'll get some more pics of that tomorrow as well.i was looking into aluminum rads as well...just can't find anyone local to build one for a comparable cost to the stock copper/brass rad.the new rads being built as replacements,by the way,seem to have thicker cores.still 4-row,just more and deeper fins,with slightly wider tubes.

how do you like your banks setup by the way?

RE: post later...

that sender was for the glow plug system, to tell if the engine was warm enough not to need to be glowed, will just always glow without it.

havent done road testing yet, need a custom pipe for the crossover exhaust bent up and getting the truck to the shop means i've had to rig up a temporary one.