Because the crank in my pickup is trashed . And from the looks of the305 cranks are far from rare. I's NEVER go 40 under, and the only
camshaft this isn't the first time my son has run it low/out of oil (a
long and sordid tale) .
This is my '86 GMC Sierra 1500 , 305 H motor and a 700R4 trans with
2.73:1 rear axle . I'll be taking parts to a shop for stuff I can't do ,
bore .030 over , check the heads out and a/n . And the crank ... the rod >journal for #1 measures 2.071" , spec is 2.0988 - 2.0998 . It might
clean up at .040 under , I don't know . Have to see what the guy at the >machine shop says . Which brings me to a question - what about welding
up a journal and regrinding ? I had one very bad experience with a
welded-up journal back in the early 80's , a $700 rebuild went 35 miles >before it ate the rod bearings . I ain't going down that road again .
On Sat, 4 Dec 2021 19:59:29 -0600, Snag <Snag_one@msn.com> wrote:
Because the crank in my pickup is trashed . And from the looks of the
camshaft this isn't the first time my son has run it low/out of oil (a
long and sordid tale) .
This is my '86 GMC Sierra 1500 , 305 H motor and a 700R4 trans with
2.73:1 rear axle . I'll be taking parts to a shop for stuff I can't do ,
bore .030 over , check the heads out and a/n . And the crank ... the rod
journal for #1 measures 2.071" , spec is 2.0988 - 2.0998 . It might
clean up at .040 under , I don't know . Have to see what the guy at the
machine shop says . Which brings me to a question - what about welding
up a journal and regrinding ? I had one very bad experience with a
welded-up journal back in the early 80's , a $700 rebuild went 35 miles
before it ate the rod bearings . I ain't going down that road again .
305 cranks are far from rare. I's NEVER go 40 under, and the only
way I'd weld a crank is if there was no other option. Gotta be a "lawn ornament" somewhere within a few miles of you with a crank that will
clean up ar 5 under or better, and you know you have a keeper. If you
want a real stout engine put in a forged 350 crank and run a
fluid-damper (the 350 is balanced a bit different from a 305 because
305 pistons are lighter) Newer cranks will fit your 86 as 86 is the
first year for one piece rear main seals.
Better yet get the rotating assembly ballanced to use the forged 350
crank with NO issues.
I just want a truck that isn't always trying to decide what gear it
wants to be in . The terrain up here is pretty hilly , and those 2.73's
just ain't gonna cut it . I'd have been happy just to get my truck back >intact and install the new 3.42 gears
On Sat, 4 Dec 2021 19:59:29 -0600, Snag <Snag_one@msn.com> wrote:
Because the crank in my pickup is trashed . And from the looks of the305 cranks are far from rare. I's NEVER go 40 under, and the only
camshaft this isn't the first time my son has run it low/out of oil (a
long and sordid tale) .
This is my '86 GMC Sierra 1500 , 305 H motor and a 700R4 trans with
2.73:1 rear axle . I'll be taking parts to a shop for stuff I can't do ,
bore .030 over , check the heads out and a/n . And the crank ... the rod
journal for #1 measures 2.071" , spec is 2.0988 - 2.0998 . It might
clean up at .040 under , I don't know . Have to see what the guy at the
machine shop says . Which brings me to a question - what about welding
up a journal and regrinding ? I had one very bad experience with a
welded-up journal back in the early 80's , a $700 rebuild went 35 miles
before it ate the rod bearings . I ain't going down that road again .
way I'd weld a crank is if there was no other option. Gotta be a "lawn ornament" somewhere within a few miles of you with a crank that will
clean up ar 5 under or better, and you know you have a keeper. If you
want a real stout engine put in a forged 350 crank and run a
fluid-damper (the 350 is balanced a bit different from a 305 because
305 pistons are lighter) Newer cranks will fit your 86 as 86 is the
first year for one piece rear main seals.
Better yet get the rotating assembly ballanced to use the forged 350
crank with NO issues.
"Bob La Londe" wrote in message news:soim84$9fi$1@gioia.aioe.org...
The big question is, "Was it just run low on oil, or was it overheated
too?"
-------------------
How can you tell?
I've completely torn down and rebuilt old motorcycle engines but never
gone beyond a top end job on a car, so this is interesting.
On Sat, 4 Dec 2021 22:45:06 -0600Losing the overdrive doesn't help low and second gear. Putting in
Snag <Snag_one@msn.com> wrote:
<snip>
I just want a truck that isn't always trying to decide what gear it
wants to be in . The terrain up here is pretty hilly , and those 2.73's >>just ain't gonna cut it . I'd have been happy just to get my truck back >>intact and install the new 3.42 gears
Those 700R4 trannies weren't all that strong. While your at it replace
it with a 350 turbo and you'll loose the overdrive and shouldn't need
the steeper rear gear change.
You build up that motor and it's very likely to take out the 700R4
in short order anyway...
On 12/5/2021 10:33 AM, Jim Wilkins wrote:
"Bob La Londe" wrote in message news:soim84$9fi$1@gioia.aioe.org...
The big question is, "Was it just run low on oil, or was it overheated
too?"
-------------------
How can you tell?
I've completely torn down and rebuilt old motorcycle engines but never
gone beyond a top end job on a car, so this is interesting.
Well when somebody rolls in with a blown radiator hose or a blown freeze plug, its not steaming anymore, and the engine seizes up when they try
to restart it that's a dead give-a-way. If you just have the engine on
hand I wouldn't know how to tell.
On Sun, 5 Dec 2021 08:42:08 -0400, Leon Fisk <lfiskgr@gmail.invalid>
wrote:
On Sat, 4 Dec 2021 22:45:06 -0600Losing the overdrive doesn't help low and second gear. Putting in
Snag <Snag_one@msn.com> wrote:
<snip>
I just want a truck that isn't always trying to decide what gear it
wants to be in . The terrain up here is pretty hilly , and those 2.73's
just ain't gonna cut it . I'd have been happy just to get my truck back
intact and install the new 3.42 gears
Those 700R4 trannies weren't all that strong. While your at it replace
it with a 350 turbo and you'll loose the overdrive and shouldn't need
the steeper rear gear change.
You build up that motor and it's very likely to take out the 700R4
in short order anyway...
3.42 or 3.55 gears gives more "pooch" at the bottom end - overdrive
returns some highway "comfort" to the setup. A well built 700R4 will
stand up to anything a healthy 305 will hand it if the gears are
right.
On 12/4/2021 8:20 PM, Clare Snyder wrote:
On Sat, 4 Dec 2021 19:59:29 -0600, Snag <Snag_one@msn.com> wrote:
Because the crank in my pickup is trashed . And from the looks of the >>> camshaft this isn't the first time my son has run it low/out of oil (a305 cranks are far from rare. I's NEVER go 40 under, and the only
long and sordid tale) .
This is my '86 GMC Sierra 1500 , 305 H motor and a 700R4 trans with >>> 2.73:1 rear axle . I'll be taking parts to a shop for stuff I can't do , >>> bore .030 over , check the heads out and a/n . And the crank ... the rod >>> journal for #1 measures 2.071" , spec is 2.0988 - 2.0998 . It might
clean up at .040 under , I don't know . Have to see what the guy at the
machine shop says . Which brings me to a question - what about welding
up a journal and regrinding ? I had one very bad experience with a
welded-up journal back in the early 80's , a $700 rebuild went 35 miles
before it ate the rod bearings . I ain't going down that road again .
way I'd weld a crank is if there was no other option. Gotta be a "lawn
ornament" somewhere within a few miles of you with a crank that will
clean up ar 5 under or better, and you know you have a keeper. If you
want a real stout engine put in a forged 350 crank and run a
fluid-damper (the 350 is balanced a bit different from a 305 because
305 pistons are lighter) Newer cranks will fit your 86 as 86 is the
first year for one piece rear main seals.
Better yet get the rotating assembly ballanced to use the forged 350
crank with NO issues.
I tend to agree. I've rebuilt a couple V8 engines (mostly Fords) and if
you are in that deep a decent crank just isn't that much compared to the
cost of your time to pull the engine and flip it over again.
The big question is, "Was it just run low on oil, or was it overheated too?" I've seen an overheated engine get rebuilt (not by me) and it
didn't last long.
On 12/5/2021 3:43 PM, Clare Snyder wrote:
On Sun, 5 Dec 2021 08:42:08 -0400, Leon Fisk <lfiskgr@gmail.invalid>[...]
wrote:
[...]
[...]
Losing the overdrive doesn't help low and second gear. Putting in
3.42 or 3.55 gears gives more "pooch" at the bottom end - overdrive
returns some highway "comfort" to the setup. A well built 700R4 will
stand up to anything a healthy 305 will hand it if the gears are
right.
I was going to say pretty much the same thing ... Thanks Clare .
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