'70 K5 blazer questions

Discussion in 'General Bushcraft Discussion' started by nothinghead, Mar 1, 2012.

  1. nothinghead

    nothinghead Guide Bushclass I

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    I am going to look at a 1970 K5 Blazer with a 350 V8 and 4 speed manual 4X4 on Saturday. In orange.

    Does anyone here have intimate experience with these? Anything I should look for other than the obvious used car things? Did these have any gremlins? I am prepared for a bit of a project, and I havn't seen any pictures (it's only down the road) but based on the guy's descriptions, it sounds decent.

    Known issues:
    Ignition needs some rewiring to use the key. Not sure of the details there yet
    Some rust here and there
    pops out of 3rd gear if you don't hold it there.

    Any words of wisdom?
     
    Last edited: Mar 1, 2012
  2. 556mp

    556mp Bushmaster Vendor Bushclass I

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    and? :4:
     
  3. nothinghead

    nothinghead Guide Bushclass I

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    Hit enter early, sorry.
     
  4. 556mp

    556mp Bushmaster Vendor Bushclass I

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    Look for rot.
    Frame rot, where supention components attach, rockers, firewall/floor pans by frame. front and rear of frame rails by rad spport... etc etc.

    Check tcase works

    Flids etc...

    Sounds like it'll need a tranny or work.... Someone probably was driving it like a big trcker not knowing how to shift, come-o..

    I dont have much/any experiance with the 70s, just 80s up.... Sorry for not being much help ;)
     
    Last edited: Mar 1, 2012
  5. Easy_rider75

    Easy_rider75 Bushwhacker

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    Electrical stuff can be rather interesting to say the least on cars at times lol. As Matt said big thing check the suspension areas I know a buddy yeah total different vehicle had the leaf spring shackle rotted through cost him big bucks to get fixed to.
     
  6. nothinghead

    nothinghead Guide Bushclass I

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    Cool.
    If I need a justification for this being here, It will become my new bushcraft vehicle. May even take it to the MD meet up if things look really good! We'll see.
     
  7. Ratty1

    Ratty1 Guide

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    What he said. Also if the hard top is no longer around carefuly check the windshield frame out. Chevy went to the permanent hard top over the front in '75 because when peopl drove the rigs down the highway without the hard top, the windshield frame would start to bend back and crack. Otherwise just the normal rust and whatnot. Those are awesome rigs with great body lines. Good luck and post some pics if you get it.
     
  8. Roamer

    Roamer Guide

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    I used to own just this vehicle. Couple things from memory:

    - The steering gearbox wears out. Watch for a lot of "on center" vagueness and wandering when driving straight ahead. Pretty big money to fix
    - There are large rubber 'donuts' between frame and body that dry out and crack, causing the body to get saggy and noisy. Look for these inside the wheelwells.
    - Unless yours was stored indoors or very well cared for, the fiberglass top may be shot fro weathering, especially around the windshield and rear window. Look for cracks and flaking. Again, big money.
    - Rust and rot behid the front wheels in the door sills, door hinges and front floorboards. Pull up the front carpet if you can to get a good look. And look for saggy doors.
     
  9. 11-Rover

    11-Rover Tracker

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    A friend of mine had a '72 Blazer 4x4,4-speed w/Granny 1st,it wasn't a K-5 & It used a 9/16" for all the vitals.It got great gas mileage for a standard 350-4 barrel & It was Solid with No inherited problems!This was a California vehicle(dry/arid conditions) so no salted roads to rot things up.Good Luck if you should buy yours!
     
  10. MysticFlight

    MysticFlight Supporter Supporter

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    Look at the rear window works properly. The 80s models broke notoriously and are expensive and a pain to repair. My buddy had one and we replaced the mechanicals 3 times in about 5 years dont know for sure on the 70s but worth checking out
     
  11. solocanoe

    solocanoe Bushmaster

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    I had one in the family growing up...and of course we had a lot of K-5's in the Army when I was in...

    you may have always found it questionable why they are regularly seen with several jerry cans mounted on them....

    until you attempt to drive more than 100 miles between fill ups! :D


    enjoy your ride, bro! they are big beatiful piece of americana, that's for sure!
     
  12. LMT66

    LMT66 Supporter Supporter

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    That's a sweet ride! Having had several 70's era Blazers, everything mentioned here is spot on. Pay special attention to the body to frame spots as well as motor mounts, steering gear box mounts and things like that.

    Your buying a money pit but if you restrain yourself you can get a lot from a little investment.
     
  13. wolfy

    wolfy Guest

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    I don't know how much salt you have to drive in back there, but here in Nebraska most of the Blazers of that era have melted away. Just be aware that this was a problem with Blazers of that vintage and check it over pretty thoroughly for structural integrity.
     
  14. Gryphonblade

    Gryphonblade Guide

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    Good rigs. I'd love to get one myself.
    As stated: rust, frame, body mounts, suspension. Frame can crack behind the steering box. Rust in the rocker panels and fenders and door bottoms. Most every part is available aftermarket through outfits like CLassic Enterprises, Classic Trucks and LMC Trucks. Check out Spike TV on weekend mornings and you'll see commercials for most of the vendors.

    Should be Dana 44 up front, 44 or a Chevy corporate (12 bolt?) out back. I'm guessing at a Munci 4 speed. Sounds like the 3rd gear dentent spring is toast. If that is all it is, should be a simple fix.

    Painless Wiring makes full replacement harnesses for a lot of rigs. If you are marginal to decent with wiring, you should be able to fix that.

    Yeah, fiberglass tops don't age well. But they can be fixed or depending on where you live, swap it out for a soft top.

    Classic rigs, getting very hard to find in decent shape: either basket cases or show trucks anymore. Also getting quite expensive as a collector's object.

    Got pics? How much? That can help a lot in helping you determine if it's worthwhile.
     
  15. ClovisMan

    ClovisMan Scout Bushclass I

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    Check the frame for cracks where the steering box mounts. They like to pull the bolts through and repairing is not fun.
     
  16. oldpinecricker

    oldpinecricker Guide

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    Im really familiar with the old Chevy Blazers and trucks having had them as my vehicle when a younger person. Sure, check for body decay, fuel lines-silinoids. Check motor and body mounts.

    I will again repeat what others said about steering box issues and cracking and breakage in the frame to steering box location. This is an plague that is common with these vehicles. Check for cracks and breakages. Even if its not cracked I would still plate that portion of the frame and upgrade install some quality high grade bolts.

    Another thing to consider is that some 1/2 ton vehicles GM made have an rear gear ratio of 3:07 ratios. This is good for highways and leaves the truck very high geared as was my '77 Chevy stepside 4WD.

    Those are some of the things to consider.
     
  17. illtemper

    illtemper Tracker

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    Very accurate info there. Popping out of 3rd was very common with the early sm465's,my 70 suburban does it, no real issue though. Good rigs, I'll never get rid of mine,and it's just an old beater...Jon
     
  18. The Warning

    The Warning Scout

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    Be picky!

    There's plenty of these still floating around, so you can afford to wait for the right vehicle and price.

    If this one doesn't work out, check out an old CUCV, they can generally be had for a few grand and generally have less mileage on them than civilian models of the same age.
     
  19. Scott Allen

    Scott Allen Guide

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    I learned to drive in one of those when it was still relatively new (tellin' my age). My dad had one with the 350 and 4 barrel Rochester or Holly carb (can't remember which). 3:73 gears, full headers and orange peeler mufflers. That thing would squall the tires in 3rd gear and already going 40mph. Loved that Blazer.
    Gryponblade hit pretty well all the things to look out for. I think the rocker panels went first on dad's. Looking forward to seeing it next weekend.

    Scott
     
  20. Keeber

    Keeber Tracker

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    +100 on steering gear mounting... I sell alot of gear boxes for early 70s gm 4x4s and they nearly always need frame repair. This is typically from rough riding on oversized tires.

    Sent from my SAMSUNG-SGH-I897 using Tapatalk
     
  21. wizard

    wizard Guide

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    I had a '76 which had a two part top. At the time it was a great vehicle. It was an automatic 4x4 with full-time 4 wheel drive. The milage was horrible, less than 10 mpg and I had a load of problems with the Rochester 4 barrel, rebuilt several times over with the same problems. QuadraJet was the type.
    As mentioned by others the steering can be an issue as front end parts wear. Mine was new and still wandered all over the road.

    I had a '70 Ford Bronco and liked it a lot better than my '76 K5. I never see either model around here anymore.

    With gas prices going wild you might want to look into something more modern with more milage potential?
     
  22. econnofoot

    econnofoot Guest

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    I owned a 79 suburban 3/4 ton, my only issues were rust and rust and more rust. Did I mention the fact it had rust? Course I didn't have 4x4 so not much help to ya there, had no issues with the 350 at all, raced that motor for years after I got rid of the rusty old suburban.
     
  23. wsdstan

    wsdstan Guide

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    Had one for a couple of years. Back when it was pretty new. Today I would look for rust, electrical wiring condition, and every other thing a used car that is 42 years old can suffer from. That year Blazer remains one of the best off road vehicles we ever owned.

    The a/c and heat is not as good as the late 70's GM vehicles and there can be hub problems if they are not greased from time to time. What Gryphonblade said covers every other thing I could think of.

    A final though on rust. If this vehicle has any, run from it. Keep looking till you find one that lived in Arizona in a garage or has been correctly repaired by replacement of all the rusted pieces. Let someone else pay for the fix up and you buy it from them. Rust can cost you so much money to fix and then show up again and drive you nuts. Its not worth messing with. Just my experienced opinion of course.
     
  24. Quill

    Quill Scout

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    These are a real nice classic. Personally I think they are pretty cool. Will it need work, more than likely. One with a good body would be expensive. 1970 was their second year of production so it is a 1st gen model. So parts are off the 2nd gen of the C/K series. As mentioned the cab mounts might be bad. Frame might be rusty etc. LMC Truck has replacement body parts. I would put a new set of springs on to bring it back to original ride height. Again you are buying a 42 year old vehicle, unless there has been a complete restoration, which would be reflected in the price. you might have some things to deal with. Used body parts will be more expensive. Used drive train parts shouldn't be to bad. Then again you might find the deal of the century.
     
  25. nothinghead

    nothinghead Guide Bushclass I

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    I have driven a 97 Blazer, an 87 accord, a 73 yamaha xs1100, 97 Saturn ls1, and currently a 07 VW GTI. Of all of these, the Blazer had the most reasonably priced parts. The GTI is incredibly painful to maintain. Cruising the internet, it looks like parts for the K5 are basically free compared to the VW. I can't believe how cheap some of these parts are.

    I am looking forward to seeing this thing. I hope it is as awesome as the guy made it sound. He wants 3500 for it. We shall see.
     
  26. oldpinecricker

    oldpinecricker Guide

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    If part availibility is desired there is no better 4WD vehicle than an Jeep. They are kinda like an Harley in that theres an huge amount of part support and lots of aftermarket.
     
  27. tree-ratsniper

    tree-ratsniper Guide

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    The pre-74 models used a points ignition that the advance weight lobes shaft & bushings wore out in causing dwell issues with the ignition timing. You may want to consider switching it to a HEI system, either from a salvage yard or aftermarket performance parts. It probably has a Quadra-jet carburetor that can be difficult to tune, you may want to consider picking up a manual or Q-jet book (or if it is indeed problematic switch it out for a Holly).
     
  28. Trekon86

    Trekon86 Guest

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    If it is in operating condition, it will still be hell on gas!

    PMZ
     
  29. econnofoot

    econnofoot Guest

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    yeah the gas would be what would keep me from it....I got a Landcruiser I can't afford to drive I took off the road.
     
  30. scojo

    scojo Tracker

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    Check that the hood doesn't bow up a bit in the middle. I had a 70s Suburban and the hood was a bit structurally weak in the middle, so that after years of use, it bowed up a bit. It was a common enough issue that I found a company that made aftermarket supports to add to the inside of your hood, so it wouldn't try to bow in half every time you shut it.
     
  31. nothinghead

    nothinghead Guide Bushclass I

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    Well, that was fun. I don't think it will happen for what he is asking, there is just a lot of rust.

    The electrical will need some serious tinkering (he had to Hotwire it to start it) and the soft top is trash. A new exhaust is necessary as well.

    It does run though. They put the shifter on the floor which is what I would have done anyway. I drove it down the road and smiled the whole way. Engine looks and sounds fine. It has a holly carb already, and BFG 35's on American racing wheels which are in awesome shape. 4wd works fine, and the frame is good. Has new polyurethane can bushings.

    Here are some pictures just for fun.
    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    It's tempting. If the rust were not there, it would be easy, but it's pretty severe. I may offer him 500 and see, but that will probably just offend him.

    I did decide that I need one of these. It's been too long since I've been that tall!


    Thanks for the help folks!
     
  32. Quill

    Quill Scout

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  33. nothinghead

    nothinghead Guide Bushclass I

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    The engine runs well, just looks bad because the current owner has been mudding with it missing a wheel well on the driver side front. Everything is dirty, but runs well. Transfer case may be leaking though. The more I think about it, the more things I can think of that would need work.


    In any case, he turned down my final offer, so I won't be taking this beast home. Too bad, as I would hate to see it continue to rust.
     
  34. siquani

    siquani Scout

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    I hot rodded a 70 C10 in high school, the only advice I would add is convert it to HEI ignition, saved me a ton of headaches.
     
  35. nothinghead

    nothinghead Guide Bushclass I

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    Well gents, Here is blazer #2. I think this one has more promise. I'll keep you posted.
    [​IMG][/url] Blazer#2 by nothinghead, on Flickr[/IMG]
     
  36. Stitch

    Stitch Scout

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    I had a 1972 GMC Jimmy years ago. I would recommend a HEI, too. I had a PERFORMANCE DISTRIBUTORS HEI and had very good luck with it.

    http://www.performancedistributors.com/

    A one wire alternator is also a good idea.
     
  37. nothinghead

    nothinghead Guide Bushclass I

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    I will certainly keep it in mind.

    The guy had lots of pictures of the body and interior, which looks amazing. I am eager to hear it and see under the hood.

    I need a more purpose built bushcraft/hunting vehicle. the VW just isn't made for the beating.
     
  38. Stitch

    Stitch Scout

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    I almost forgot, mine had a 350 with headers. They killed starter solenoids very quickly due to the heat. Up to 1970 have 4 wheel drum brakes. 1971 and up have front disc brakes.
     
    Last edited: Mar 30, 2012
  39. nothinghead

    nothinghead Guide Bushclass I

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    This new one is a 79 and a 350. I think that may already have HEI. He says it has a part time 4wd conversion in it.

    I prefer the disc brakes, so that will be a plus in my book.
     
  40. skorpyd

    skorpyd Scout

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    That 79 looks pretty good. Reminds me of my 76 stepside shortbed. Had a lot of fun with it. It loved gas. The body style of the 70 is my all time favorite though. As far as what to look for, lot's of great advise already given.

    Now if you really want a great old suv, find a Scout II like my old 79
    [​IMG]
     
  41. Ratty1

    Ratty1 Guide

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    I had a '79 that I converted to part time also. It's nice because you wind up having low range in two wheel drive, which I found myself using more that four wheel drive out in the mountains. The pic of that '79 looks like the truck is pretty clean. It already has HEI and there's plenty of room in the engine compartment when you need to work on it. That truck also has the 12 bolt rearend. It's a c-clip axle that tends to snap the snub off where it's machined for the c-clip. When they snap the axle the wheel along with the shaft start to walk right on out. The good news is you can buy upgraded shafts at a pretty low price. It also has the ten bolt front end which shares the outers with the dana 44. As long as you don't try to turn too big of a tire and don't beat on it too hard, those axles should be fine.
     
  42. nothinghead

    nothinghead Guide Bushclass I

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    My plan is to keep it stock height. I don't need a grave digger.

    That scout picture is awesome! I would prefer a Scout, but they seem to have all rusted away here in the Mid Atlantic.
     
  43. skorpyd

    skorpyd Scout

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    The Scouts did tend to rust. I see some nice one from out in the desert areas once in a while. Thanks, on the pic, it cost me a bundle. As I look back it was worth it. At the time not so much.
     
  44. Scott Allen

    Scott Allen Guide

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    Trey,

    Don't discoount the pre-77 Broncos (the smaller ones). I had a '72 as my first 4wd. I traded the stock 302 for a 351 Cleveland, change the shifter to a Hurtz "Quick Silver" floor stick, raised it 4" and put 14:35 Ground Hawgs on it. Unstoppable!

    Scott
     
  45. nothinghead

    nothinghead Guide Bushclass I

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    I looked at some broncos, but I just don't know anything about them. They seem to be in worse shape too. If the right one came around, I would be all over it though.
     
  46. Scott Allen

    Scott Allen Guide

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  47. nothinghead

    nothinghead Guide Bushclass I

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    Well that solves that problem...
     
  48. nothinghead

    nothinghead Guide Bushclass I

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    Well gents, it looks like I will be taking the 79 blazer. She is in great shape and at an amazing price. I'll let you know more when I have it in my possession.
     
  49. Lerxst2112

    Lerxst2112 Scout

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    Good luck with it Trey.
     
  50. 2500ak

    2500ak Tracker

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    It's not enough to observe that an engine runs, and seems to run well.

    If you really want to know what condition the engine is in go to a parts store and get a vacuum gauge (around 30$), or borrow one, or maybe you already have one. Hook it up to a vacuum port on the carburetor and watch the reading.

    If the needles shivers then the valve stem seals are starting to go. This is a fairly easy fix and takes about an afternoon to complete.

    If it is low, but steady then there is probably a vacuum leak, or the mix is off, or the timing is off. All of these are easy to fix. You can even use the vacuum to set the timing and mix, just adjust until the vacuum is maximized.

    If the needle dips at regular intervals then the engine has a burnt valve. Argue the price down or let it go. You'll need to pull the head and replace the valve. Possibly the valve seat. It's best to replace all of the valves at the same time (not really expensive) but a long tedious task.

    While you're at it, pop the dist cap off and rotate the engine back and forth with a ratchet on the crank bolt. There should be no lag, and at the most very little lag between the engine turning and the rotor turning. If there is then the engine has a stretched timing chain. Another long a tedious fix.

    If the engine makes any ticking or popping noises pull plug wire off individually until it stops. Then you know which cylinder is making the noise.


    If the vac test shows a valve problem, pull a valve cover. You can tell a bent pushrod or a worn cam lobe by spinning the engine over and watching the rockers. Check to see if any of the rockers are overly loose, or unmoving when the engine cranks.

    Test the oil pressure with a mechanical gauge. Off the top of my head I think a 350 should have more than 20 psi at idle. If it's really old and in need of a rebuild it could be as low as 5psi and functioning fine, but close to the end of it's natural life.

    Have a close look at the oil on the dipstick. It should be black, or amber if it's fresh, but not brown. If it looks like a chocolate milk then you've got water getting into it. Probably from a headgasket or a cracked block/head.

    Open the rad cap while it's cool and start the engine. There should be no bubbles of gas coming up through the fluid.

    Put a multimeter on the battery terminals with the engine off. Should read about 12v. If not, bad battery.

    Engine on should be about 14v. If not, bad alternator.

    check the exhaust:
    White smoke - water
    blue smoke - oil
    black smoke - rich mixture

    That's how I tell if an old truck engine is a good candidate to make a project out of.

    That full time t-case is probably a NP203. I'd take a gear driven NP205, or a Dana 24 over the 203 any day. The chain drive 203 is pretty marginal in a truck application imo.
     

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