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-   -   1971 K20- project just get driveable!! (https://67-72chevytrucks.com/vboard/showthread.php?t=590642)

Ol Blue K20 02-13-2014 12:24 AM

Re: 1971 K20- project just get driveable!!
 
The k20 is looking good and nice find on the parts truck.

DeadheadNM 02-13-2014 12:30 AM

Re: 1971 K20- project just get driveable!!
 
Jud how's the rear bumper on the new parts truck? Looks like a cool and heavy period correct step bumper...good find on the parts C20.

mx289 02-13-2014 06:29 PM

Re: 1971 K20- project just get driveable!!
 
Just read through the build.What a great truck.
I will be watching this and your others.You have some cool k20's.

And its nice to see it used as a truck.! :lol:

Tom

Dieselwrencher 02-13-2014 08:57 PM

Re: 1971 K20- project just get driveable!!
 
Great work on the truck and nice score on the parts truck. It's in really nice shape. Can you go into more detail on the blower motor? I'm interested in this as I'd like to put the best one in mine before I actually make it a driver. :lol:

Vintage Windmills 02-15-2014 11:38 AM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by DeadheadNM (Post 6523295)
Jud how's the rear bumper on the new parts truck? Looks like a cool and heavy period correct step bumper...good find on the parts C20.

I think its pretty good. May have to use it on one of my trucks. Are you looking for one?

Quote:

Originally Posted by mx289 (Post 6524254)
Just read through the build.What a great truck.
I will be watching this and your others.You have some cool k20's.

And its nice to see it used as a truck.! :lol:

Tom

Thanks, good to know people are following along:chevy:
After this thing is on the road, I will resume working on the blue K20. Then I may do a quickie on the 71 K20 292 truck just to get it running again. Then work in a cummins conversion lol.

Quote:

Originally Posted by Dieselwrencher (Post 6524461)
Great work on the truck and nice score on the parts truck. It's in really nice shape. Can you go into more detail on the blower motor? I'm interested in this as I'd like to put the best one in mine before I actually make it a driver. :lol:

Ryan, the blower is what Rock auto had listed for both the heat only and AC trucks. It sounds like the heat only trucks originally had a weak 5 or so amp motor. This one draws about 16 and blows like a supercharger;) I was expecting a fuse to pop but so far so good. Course I've only run the motor about 5 minutes so far. There is a hole on the side of the motor (it must cross reference with a newer truck) that is for a little tube to connect to for cooling the motor. I could connect a tube to my heater box, but I'm not sure I want to modify the original box...

Ol Blue K20 02-15-2014 11:57 AM

Re: 1971 K20- project just get driveable!!
 
I would put the tube in it and point it down just to keep the water out. It would still get air to cool it.

DeadheadNM 02-15-2014 12:01 PM

Re: 1971 K20- project just get driveable!!
 
Not looking for one but thanks for asking. I really like those old, thick steel step bumpers and have one painted and ready for my K20. I actually looked into having one chromed but was told by the plating co. that as mine had the diamond pattern on top the chrome wouldn't adhere well and would fail - too bad.

Dieselwrencher 02-17-2014 03:29 PM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by Vintage Windmills (Post 6526993)
Ryan, the blower is what Rock auto had listed for both the heat only and AC trucks. It sounds like the heat only trucks originally had a weak 5 or so amp motor. This one draws about 16 and blows like a supercharger;) I was expecting a fuse to pop but so far so good. Course I've only run the motor about 5 minutes so far. There is a hole on the side of the motor (it must cross reference with a newer truck) that is for a little tube to connect to for cooling the motor. I could connect a tube to my heater box, but I'm not sure I want to modify the original box...

Thanks Jud. I think I'll just purchase one fom there and give it a whirl.

Vintage Windmills 02-19-2014 10:10 PM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by Dieselwrencher (Post 6530365)
Thanks Jud. I think I'll just purchase one fom there and give it a whirl.

Hey, I see what you did there;)

I got quite a bit done on the truck this weekend. Pretty much didn't do anything else but work on it.

Wire wrapped to keep new ducting on defrost vents:
http://i221.photobucket.com/albums/d...P1010251-2.jpg

Decided to replace the poorly engineered original pump with something more modern:
http://i221.photobucket.com/albums/d...P1010250-1.jpg

only bad thing is it loses the prime and has to be reprimed all the time. I think I will install a checkvalve or just look for a different pump. This one is technically supposed to mount directly to tank.

Rebuilding the turn signal setup:
http://i221.photobucket.com/albums/d...P1010254-2.jpg

Sig parts all cleaned up and ready to reinstall. I got a palmfull of dust out of the old one. Remember, this truck had no back window and sat in a field for a couple decades.
http://i221.photobucket.com/albums/d...0/P1010253.jpg

Column (with new upper bearing) back in and radio delete and new cig tray installed:
http://i221.photobucket.com/albums/d...P1010257-1.jpg


What? I have to fit this grommet over this speedo cable!!! Armor all (lube) and the vice to the rescue. I got it but it split the grommet a little. Next time, think I will just cut the grommet.

http://i221.photobucket.com/albums/d...P1010252-1.jpg

Hood and different inner fender back on. That was fun by myself:waah: Good thing I am stronger than I was in my 20's. Easier to put on muscle these days thankfully.
http://i221.photobucket.com/albums/d...P1010255-1.jpg

Getting real close, need to get shoulderbelts and put them in, hook up fuel sender and figure out why the dash lights are always on, then the seat can go back in. Also need to rebuild pass door mechanisms and put mirror on driver side.
http://i221.photobucket.com/albums/d...P1010258-1.jpg

Dieselwrencher 02-19-2014 11:31 PM

Re: 1971 K20- project just get driveable!!
 
Great work! I always wondered if they put the grommet on before they crimped the cable ends on because they aren't real forgiving when you're trying to force that cable nut through that small hole. :lol:

swamp rat 02-19-2014 11:49 PM

Re: 1971 K20- project just get driveable!!
 
Nice work!

Ol Blue K20 02-20-2014 12:55 PM

Re: 1971 K20- project just get driveable!!
 
Man, that truck is looking great what a difference from what it started from....

mx289 02-22-2014 12:36 PM

Re: 1971 K20- project just get driveable!!
 
Truck looks great.

Really like the look.

Tom

Vintage Windmills 02-26-2014 02:06 AM

Re: 1971 K20- project just get driveable!!
 
Thanks guys, I ordered 2 of these and a lapbelt yesterday.
http://wescoperformance.stores.yahoo...t-gm-retr.html

too cold here to heat the shop with propane these days, plus I've been wiring in the bathroom project.

Dieselwrencher 02-27-2014 12:26 AM

Re: 1971 K20- project just get driveable!!
 
Thanks for that link. I need to measure my seat to floor on my truck and I will be ordering some of those. I've been waiting because the others I had seen on the net looked cheesy IMO.

swamp rat 02-27-2014 12:40 AM

Re: 1971 K20- project just get driveable!!
 
The set I bought thru a local vender didn't have a plastic housing on the inside belt. Its almost a two handed job to get it buckled trying to hold the inner buckle. If you can get a set with a plastic sleeve on the inner buckle side I would recommend it.

mx289 03-01-2014 11:08 AM

Re: 1971 K20- project just get driveable!!
 
Thanks for the link Vintage.
The belts look really nice and 29 colors.!

Tom

Vintage Windmills 03-07-2014 10:18 PM

Re: 1971 K20- project just get driveable!!
 
Belts showed up. Should have some time to work a little on the truck this weekend.

Thinking I need to:
-Install belts
-Replace front rotors and calipers (never did since debating what front axle to run)
-Check valve in wash fluid line
-Install seat
-Install rebuilt Qjet
-Hook up gas gauge

hgs_notes 03-08-2014 09:46 AM

Re: 1971 K20- project just get driveable!!
 
Looking real good. I think I still need to get my windshield washer working. Kind of forgot about that. And my wipers squeak real bad too. Looks like I found a couple things to keep busy on until I can get it back on the road.

Vintage Windmills 03-11-2014 12:56 AM

Re: 1971 K20- project just get driveable!!
 
2 Attachment(s)
Well with the big rear bumper and lift, I need to drop the hitch a little and create a custom bracket to mount it. I used the software we use at work for design (Solidworks). I'm going to weld or bolt one of these on each side. Also checked the stress at the rear bolt, which would be the highest loaded. Its not exactly detailed to the proper degree but this simplified simulation is telling me its still not exceeding the material strength (31,000 yield for mild steel), even assuming 3000 lbs is reacted on that one bolt with a little washer. The real washer will be thicker and have more area.

hgs_notes 03-11-2014 07:14 AM

Re: 1971 K20- project just get driveable!!
 
Looks easy enough to build. No way will it see that kind of force all downward like that outside of an accident. It would have to be 6000 lbs downward total because you have 2 sides. And pulling force would be shared across the other 2 bolts of each side, so it should handle anything the truck is capable of pulling. It actually looks a lot like the hitch set up I have on my Jimmy.

swamp rat 03-11-2014 05:15 PM

Re: 1971 K20- project just get driveable!!
 
Are you saying that with my 4" lift and 33" tires i may need to lower my hitch? I never thought much about that, can you tell me how high the bottom of the reciver hole is to the floor now and what you think would be ideal?

I do plan on buying a flatbed trailer and figured i'd need a drop hitch, but now i'm wondering if maybe there is not a drop hitch low enough.

Any help appreciated.

Low Elco 03-12-2014 08:26 AM

Re: 1971 K20- project just get driveable!!
 
On these tall trucks, I've always wondered about the firce multiplier of the 4-6" drop drawbars. It's one thing to have the trailer's force in a nominally linear push/pull. Wonder how it works with a 4/6/8(!)" lever applied. Hitch looks good!

Vintage Windmills 03-14-2014 11:13 PM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by hgs_notes (Post 6569083)
Looks easy enough to build. No way will it see that kind of force all downward like that outside of an accident. It would have to be 6000 lbs downward total because you have 2 sides. And pulling force would be shared across the other 2 bolts of each side, so it should handle anything the truck is capable of pulling. It actually looks a lot like the hitch set up I have on my Jimmy.

Yep, but I like to estimate high on the force since in reality, loads are dynamic and fatigue issues can occur at stresses lower than the yield stress.


[quote=swamp rat;6569959]Are you saying that with my 4" lift and 33" tires i may need to lower my hitch? I never thought much about that, can you tell me how high the bottom of the reciver hole is to the floor now and what you think would be ideal?

I do plan on buying a flatbed trailer and figured i'd need a drop hitch, but now i'm wondering if maybe there is not a drop hitch low enough.

On my factory tow package k2500hd, its about 16" to the bottom of the receiver hole and its worked really well for a straight hitch on big tandems and a mild drop on smaller trailers. You can definitely get away with a drop hitch if you arent hauling very heavy loads. I looked at your hitch and its not one of the strongest setups since the mount is the shorter frame interface. That said, the mfg rating is still probably quite high but would be reduced with a large drop hitch. the drop will not cause greater stress from the tongue weight of the trailer but will when braking due to the offset and resulting momen

Quote:

Originally Posted by Low Elco (Post 6571111)
On these tall trucks, I've always wondered about the firce multiplier of the 4-6" drop drawbars. It's one thing to have the trailer's force in a nominally linear push/pull. Wonder how it works with a 4/6/8(!)" lever applied. Hitch looks good!

Those arent nearly as bad as the 12" ones ive seen on some of the big lifted trucks!
wouldnt be too hard to calculate the load increase under hard braking. we could assume full deceleration in 4 seconds or so, then get ft/sec^2, then F=ma, then multiply that force by the drop distance (from frame bottom, not recvr), and divide by length of interface at frame. That will be the additional amount of force reacted by the bolts at the rear.

swamp rat 03-15-2014 01:24 AM

Re: 1971 K20- project just get driveable!!
 
Quote:

On my factory tow package k2500hd, its about 16" to the bottom of the receiver hole and its worked really well for a straight hitch on big tandems and a mild drop on smaller trailers. You can definitely get away with a drop hitch if you arent hauling very heavy loads. I looked at your hitch and its not one of the strongest setups since the mount is the shorter frame interface. That said, the mfg rating is still probably quite high but would be reduced with a large drop hitch. the drop will not cause greater stress from the tongue weight of the trailer but will when braking due to the offset and resulting momen


Those arent nearly as bad as the 12" ones ive seen on some of the big lifted trucks!
wouldnt be too hard to calculate the load increase under hard braking. we could assume full deceleration in 4 seconds or so, then get ft/sec^2, then F=ma, then multiply that force by the drop distance (from frame bottom, not recvr), and divide by length of interface at frame. That will be the additional amount of force reacted by the bolts at the rear.
Thanks for the info on your towing setup.

My hitch is class IV if i use a load leveler its rated at 12,000/600 without 10,000/500 I'm hoping to be able to tow a 18' tandem flatbed with another 67-72 pickup on it Or even a 24' camp trailer.

Actually looking at it i feel the hitch is stronger than the truck frame so have been a little concerned.

So by adding the brackets your making do you feel that it is stronger than using a drop hitch? lets assume i needed a 4" drop and the brackets accomplish this drop.

Hate to say it but i don't understand your formula

98Murray 03-15-2014 02:34 AM

Re: 1971 K20- project just get driveable!!
 
This is a great thread! Good looking old farm truck!

Vintage Windmills 03-17-2014 12:32 AM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by swamp rat (Post 6576004)
Thanks for the info on your towing setup.

My hitch is class IV if i use a load leveler its rated at 12,000/600 without 10,000/500 I'm hoping to be able to tow a 18' tandem flatbed with another 67-72 pickup on it Or even a 24' camp trailer.

Actually looking at it i feel the hitch is stronger than the truck frame so have been a little concerned.

So by adding the brackets your making do you feel that it is stronger than using a drop hitch? lets assume i needed a 4" drop and the brackets accomplish this drop.

Hate to say it but i don't understand your formula

I was just typing quick on my smartphone, sorry about the rough formulas. I'll try to type up a quick document that outlines it.

You would be better off with a set of brackets like I've got since they bolt to a longer section of frame. The load on the frame is directly proportional to distance between the front and rear set of bolts.


Quote:

Originally Posted by 98Murray (Post 6576045)
This is a great thread! Good looking old farm truck!

Thanks, I am having fun and not sweating scratches with this truck!

Vintage Windmills 03-17-2014 12:39 AM

Re: 1971 K20- project just get driveable!!
 
1 Attachment(s)
Belts and seat in. I like the belts but the hardware kit didn't have the coarse thread 1/2-13 bolts. also I should post pics of the driver side retractor position for some opinions. the tank forces it out and not in the best spot. I may just drill and mount it to match passenger side angle.

thelonerife 03-17-2014 12:49 AM

Re: 1971 K20- project just get driveable!!
 
Great looking truck!

swamp rat 03-17-2014 04:09 AM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by Vintage Windmills (Post 6579409)
I was just typing quick on my smartphone, sorry about the rough formulas. I'll try to type up a quick document that outlines it.

You would be better off with a set of brackets like I've got since they bolt to a longer section of frame. The load on the frame is directly proportional to distance between the front and rear set of bolts.




No need to update the formulas for me, i did way too many of them during my machinist apprenticeship back in the 90's :)

I get what your saying tho, the breaking forces on a drop hitch would transfer to the hitch and frame so a longer hitch flange would help distribute the force along the frame. with my rear fuel cell i was having doubts about drilling thru and sandwiching the tank flange with the rear bolt of my old hitch, still thinking about possibly adding some kind of bracing to the new one.

Maybe after I'm finished struggling with my rear quarter damage I'll spend a little time rethinking the issue.

Vintage Windmills 03-18-2014 10:12 PM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by swamp rat (Post 6579540)
No need to update the formulas for me, i did way too many of them during my machinist apprenticeship back in the 90's :)

I get what your saying tho, the breaking forces on a drop hitch would transfer to the hitch and frame so a longer hitch flange would help distribute the force along the frame. with my rear fuel cell i was having doubts about drilling thru and sandwiching the tank flange with the rear bolt of my old hitch, still thinking about possibly adding some kind of bracing to the new one.

Maybe after I'm finished struggling with my rear quarter damage I'll spend a little time rethinking the issue.

Yep, the rear tanks are nice but complicate things. I'd like to go to a rear tank at some point, need to read up on what you and others used.

Vintage Windmills 03-26-2014 08:00 PM

Re: 1971 K20- project just get driveable!!
 
Swapped the rebuilt carb on the truck and took it for a spin. Got insurance on it now too! Nice to have a seat in it :) Pulls to the right still, need to work on front brakes and tune the engine, she stumbles a bit on accel but then pulls pretty good so should just be a matter of tuning.

Vintage Windmills 03-26-2014 08:06 PM

Re: 1971 K20- project just get driveable!!
 
1 Attachment(s)
Picked this diesel truck up on Saturday, Not sure what truck the parts will be used in. Its got a gearvendors setup, overdrive (getrag 5spd), dana 60 front and 3.55 gears.. so you can idle at a cool 50mph! Shes rusty and the Dana 70 rear is junk.

I think for now I'll swap in a Dana 60 3.55 rear I have to see how good the driveline is and how I like the gearvendors.

glimmertwin01 03-26-2014 08:22 PM

Re: 1971 K20- project just get driveable!!
 
Crusty Old Dodge... but it might make a good winter rat... u have all summer to seal it up, then beat it like the rented mule it is... :)

Dieselwrencher 03-26-2014 10:53 PM

Re: 1971 K20- project just get driveable!!
 
Nice score on the 1st gen Dodge. Is the GV before the Tcase or after on that truck?

Vintage Windmills 03-26-2014 11:38 PM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by glimmertwin01 (Post 6596901)
Crusty Old Dodge... but it might make a good winter rat... u have all summer to seal it up, then beat it like the rented mule it is... :)

Maybe, shes so rusty though, chips fall off when you slam the doors. One of the rear shackles Is almost rusted through too. Its crazy how these trucks rust. Its also crazy how cramped the cab is. Even my 88 chevy was so much better designed in the cab especially. I know, preaching to the choir here, this is a chevy site!

Quote:

Originally Posted by Dieselwrencher (Post 6597251)
Nice score on the 1st gen Dodge. Is the GV before the Tcase or after on that truck?

Thanks Ryan. I'm still looking for the parts for the other cummins at some point. This one has the overdrive after the np205, per Gearvendors install instructions. Does this np205 have the same output shaft as the one in my ochre truck? Trying to figure out how easy it would be to swap in the K20. Still surprised this truck had one with the 3.55 gears.

ryanroo 03-27-2014 07:16 AM

Re: 1971 K20- project just get driveable!!
 
the 205 in the dodge is a 29 spline. it is specific to dodge manuals of that vintage. not a bad piece to have laying around. you can use it with any dodge manual(that i know of, the newest stuff i dont know the specs on) that came behind a diesel. so if you want to swap a cummins into an old chevy and use a 205 that is the case to have.

Dieselwrencher 03-27-2014 03:51 PM

Re: 1971 K20- project just get driveable!!
 
Quote:

Originally Posted by Vintage Windmills (Post 6597342)
Thanks Ryan. I'm still looking for the parts for the other cummins at some point. This one has the overdrive after the np205, per Gearvendors install instructions. Does this np205 have the same output shaft as the one in my ochre truck? Trying to figure out how easy it would be to swap in the K20. Still surprised this truck had one with the 3.55 gears.

Jud, I don't believe the dodge 205 has the same output as the chevy. If I remember correctly, the dodge ones are larger in diameter. I could be wrong though. I've never tried to put a dodge yoke on a chevy 205. I could be wrong and they could be the same. That woiuld be nice. The dodges use a 1410 u-joint any way so I'd use it over the stocker GM one anyway.

ryanroo 03-27-2014 09:20 PM

Re: 1971 K20- project just get driveable!!
 
wow, i totally missread that... haha

the rear output on the dodge and gm are the same... i think. i do think the dodge diesel varient had a different PN, but it was dimensionally the same as any gm fixed rear 205 with a plastic gear. the difference was in the machining process to make it a bit beefier. there is a difference in the rear outputs with metal speedo gear, but i dont know how it would affect the GV.

the front output will be a bigger version. the dodge was 32 spl where gm was 30 spl.

Vintage Windmills 03-27-2014 09:59 PM

Re: 1971 K20- project just get driveable!!
 
Thanks guys, I could have been more clear. I am thinking on just removing the gearvendors by itself and mounting in my ochre truck if it will bolt right up. Then drive the dodge w/o a gearvendors for a year or so until I'm ready to transplant the cummins, trans, and dodge tcase.


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