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this has been discussed for ages, but here goes anyway...
I understand the assignment, but need help w/ the execution
I've removed the access panels in the cab firewall exposing the front mount bolts.
I've soaked both sides from above w/ penetrating oil. sprayed some on the bottoms of the bolts as well, but not sure how much capillary action is wicking the oil north.
long 1/2" drive socket with breaker bar won't fit because it's too tall.
short 3/8" drive socket with breaker bar fits, but limited travel as i'm hitting the shock and mount.
regular 3/8" drive ratchet fits, but can't seem to get the bolt to budge. tried tapping with a 3# sledge.
the limited opening is challenging because you only get like 10-20* of movement with the longer breaker bar before hitting the shock mount.
am i wishful/naive to think that I can hold the bolt from above and hit the retainer with a deep impact socket?
I know that I'll need to devise a puller to get that retainer off from the bottom, so doubtful that it'll spin with an impact gun.
should I jack up the cab and try to get some penetrating oil to drip down the bolt somewhere under the cab? would melting the rubber bumpers out give better access to this?
I've been using WD40 penetrating oil, but is PB blaster the magic elixir?
So far I've only attempted to crack the PS front bolt.
TIA
Use a 1/2 dv short socket and a 1' or 2' breaker bar to hold the bolt head inside the cab mount. Use a HD impact (I mean 600 ft lbs of break away torque impact). Ingersall Rand air impact tool with a 5 or 6 point impact rated socket on the nut from below and go for it. I ended up breaking one bolt and then some how got the other one loose.
I loosened mine, but did not totally remove them when I was thinking of new bushings, but then just shimmed the one at right rear corner that was tightened too much in 1977, about 3/16" fixed mine ... but before loosening them, I got a not expensive hex shaped 7/16-14 die (I think that was it) and used it to chase the rusty threads exposed below, even turned it around and run it all the way to the nut with some oil, to clean the threads.
Use a 1/2 dv short socket and a 1' or 2' breaker bar to hold the bolt head inside the cab mount. Use a HD impact (I mean 600 ft lbs of break away torque impact). Ingersall Rand air impact tool with a 5 or 6 point impact rated socket on the nut from below and go for it. I ended up breaking one bolt and then some how got the other one loose.
I'll try the ATF/acetone mixture and the air impact. thanks.
Originally Posted by tbear853
I loosened mine, but did not totally remove them when I was thinking of new bushings, but then just shimmed the one at right rear corner that was tightened too much in 1977, about 3/16" fixed mine ... but before loosening them, I got a not expensive hex shaped 7/16-14 die (I think that was it) and used it to chase the rusty threads exposed below, even turned it around and run it all the way to the nut with some oil, to clean the threads.
bought a 7/16-14 die. I'll clean up the threads before using the impact gun.
Regular WD-40 is a Water Displacement product, it doesn't wick the same as a true penetrating oil and doesn't have the chemicals that are really good at breaking down rust . Use something like PB, Kroil, or even another WD-40 product, but make sure it says "Penetrating oil". Or use that acetone/alcohol mixture which is probably even better and the additives in trans fluid actually neutralize minor rust. I keep old AT fluid and regular wipe down any exposed steel on my vehicles and yard equipment, along with my steel stock and any parts I'm storing outside.
I've been dealing with rust all my life thanks to heavy salt use in the winter. Chase the threads, wire brush as much as possible, do a couple heat, oil, cooling cycles on the nut, tapping it lightly with a something heavier like a long socket extension or a wrench, the vibration helps the oil to wick in. Then let it sit at least overnight and allow the oil to work. When you go back to do it, do the heat-tap-cool cycle a couple times, then get the nut hot, soak it in oil and try breaking the bolt loose, try going both ways if it doesn't move, sometimes they'll get a little tighter, which is enough to break the rust, then work it back and forth as you flood it in oil. The more you soak it and let it marinade, the easier it'll get. You can also wrap an oil soaked paper towel or rag around the threads to keep it wet longer. I even bought some dental picks for really heavy rust so i can clean out inside the nut around the base of the threads and it's made a huge difference. I rarely break bolts or strip stuff out if I take the time to clean and soak it.
Regular WD-40 is a Water Displacement product, it doesn't wick the same as a true penetrating oil and doesn't have the chemicals that are really good at breaking down rust . Use something like PB, Kroil, or even another WD-40 product, but make sure it says "Penetrating oil". Or use that acetone/alcohol mixture which is probably even better and the additives in trans fluid actually neutralize minor rust. I keep old AT fluid and regular wipe down any exposed steel on my vehicles and yard equipment, along with my steel stock and any parts I'm storing outside.
I've been dealing with rust all my life thanks to heavy salt use in the winter. Chase the threads, wire brush as much as possible, do a couple heat, oil, cooling cycles on the nut, tapping it lightly with a something heavier like a long socket extension or a wrench, the vibration helps the oil to wick in. Then let it sit at least overnight and allow the oil to work. When you go back to do it, do the heat-tap-cool cycle a couple times, then get the nut hot, soak it in oil and try breaking the bolt loose, try going both ways if it doesn't move, sometimes they'll get a little tighter, which is enough to break the rust, then work it back and forth as you flood it in oil. The more you soak it and let it marinade, the easier it'll get. You can also wrap an oil soaked paper towel or rag around the threads to keep it wet longer. I even bought some dental picks for really heavy rust so i can clean out inside the nut around the base of the threads and it's made a huge difference. I rarely break bolts or strip stuff out if I take the time to clean and soak it.
thanks for the info. I'm using WD-40's penetrating oil, but will try the ATF/acetone trick as well. I'll try to jack up the cab a bit to get some space between the crushed bumper and the frame to try and get some fluid to wick down the bolt itself. Right now I'm only spraying from above and on the very end of the exposed bolt below the nut and not sure if any of it is getting where it needs to go. I also bought a die to clean the threads of the bolt below the nut. I'll also try heat/cool cycles.
From what I'm hearing, most of the work is done from below using an impact wrench while holding the bolt from above, correct? There's just not enough room to swing a wrench in that tiny access hole.
does anyone sell just the retainers? I had to cut the front core support retainers off and already have the energy suspension bumpers, but need to buy just the metal retainers/sleeves and bolts.
Take a look at the image from LMC Truck website.
The lower nut is also welded to the lower washer assembly with a long shoulder, and long threads.
I would put some heat on the nut to help penetrants to find their way into the threads. Like you mentioned trying to get oil down inside is nearly impossible.
My suggestion too is hold the head of the bolt secure and use an impact gun on the bottom both directions. If not budging, repeat the heating process, and pray.
I do realize that lower nut is connected to the washer and sleeve. Realized this after cutting off the core support mounts. I’ll keep heating and trying to bust it loose. I’ve been dealing with neck spasms since removing the engine last week so will take a brief hiatus from working in the truck
Interesting. What's the active lifespan of the trans fluid and acetone given that acetone is highly evaporative. Does it require a fast response?
I used PB Blaster but also needed a universal joint with the socket
.
just to close the loop, got the front bolts off by using a ratchet to hold the bolt from above and an air impact to spin the retainer from below.
the ATF/acetone juice is amazing after a couple of days soak. saturated the bolt from above. I also used a die to chase the threads of the first bolt but busted off w/ the impact on the other side.
now to try my luck with the rear bolts. I'm assuming I need to remove the seats to access these bolt heads?
You don't "have" to remove the seat unless your flooring can't be moved out of the way far enough, but it does give you more room to work. The bolt heads are hidden under a rubber plug.
You don't "have" to remove the seat unless your flooring can't be moved out of the way far enough, but it does give you more room to work. The bolt heads are hidden under a rubber plug.
Slide/adjust the seat full forward then flip the back up. Pop the rubber plug and have it. I used a vice grip to hold the nut (on the underside) and then impact wrench the head. D3TZ-1000155-B.. Absorber (rubber cushion) - Lowerradiator support and lowerfront & rear cab mounts / Obsolete CARPENTER NOS OBSOLETEPARTS in Concord NC = 800-476-9653. PARTS INTERNATIONAL in Farmers Branch TX = 888-727-0418.
GREEN SALES CO. in Cincinnati OH = 800-543-4959.
WESLEY OBSOLETE PARTS in Liberty KY = 606-787-5293.
------------------------------------------------------------------------- D3TZ-1000396-C.. Absorber (rubber cushion) - Upperradiator support andupperfront and rear cab mounts / Obsolete PARTS INTERNATIONAL
CARPENTER NOS OBSOLETEPARTS GREEN SALES CO.
WESLEY OBSOLETE PARTS
