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WayneC

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Posts posted by WayneC

  1. Any suggestions for sources or fixes?

    Today I was looking through a stash of Microsoft Word documents I've saved over the years, some of which are Avanti-related, and I came across this (perhaps it'll be of some help)

    I'm not sure whether I wrote it, or if I found it somewhere...

    Thoughts on checking a bad tachometer on an Avanti:

    Luckily I haven`t had to worry about this problem as yet, but here`s a couple of hints and thoughts: start by checking all the wiring to the tach sender and the tach itself for loose or corroded connections.

    The tach sender is a flat cannister about 4 inches in diameter by a half inch high, located on top of the horizontal steel dash support, just below and to the right of the tach head.

    There are 4 terminals on top of it.

    The tach sender gets its rpm timing signal from the negative terminal on the coil to the terminal marked `D`.

    The sender gets 12v from the circuit used for the automatic shifter... this is the 2-amp fuse in the fusebox closest to the circuit breakers... check the fuse and check for 12v to the sender terminal marked `+`.

    There is a terminal marked with the grounding symbol which should have a white ground wire attached... check this wire for continuity to body ground.

    Lastly, there is a yellow wire from the tach sender terminal marked `M` to the brass terminal on the back of the tach head.

    On the tach head there also are 2 black power leads for night illumination bulbs, and 2 white leads for ground for those same bulbs.

    I`m not an electrical techie so I do not know how to check for the signal from the coil to the tach sender `D` terminal and from the sender to the head (yellow wire) but I guess I`d play with the 12v setting on a fuse-protected ohmmeter to see if that picks up any kind of reading at the `D` and `M` terminals on the sender and the brass terminal at the tach head that varies with engine rpm.

    Hope that all made some sense.

  2. Gunslinger, I replaced the stock distributor/coil setup with a GM HEI distributor in my '71 Avanti years ago and found the tach worked fine getting its signal from the HEI's tach attach terminal;

    required my finding the correct GM wire terminal to mate to the HEI tach (and I replaced the pink resistor wire to the distributor with a normal wire as part of the swap).

    Can't say for certain, but my guess is that the Crane output signal is probably the equivalent (an intermittant 12v signal, same as a points distributor) and would probably work if he had a working sender.

    One possible way to find out if the sender works might be to run a wire from the tach terminal of another running car (either points distributor or HEI) to his sender's input wire (with Avanti ignition on).

    My guess is that his tach will register if the Avanti's sender and tach are both good.

    There may be a way to use a multimeter to check the output of the sender, but you'd need a known good Avanti to find out what the reading should look like... my guess is that the sender

    puts out a variable voltage signal.

    Beyond that, he'd probably need to swap parts with another Avanti to find out which component is bad, or as you suggest, swap out the old speedo & sender for a modern electric tach setup.

  3. Thanks for sharing. I don't remember that article, but I did have quite a bout with the passenger side window on one of my Avanti's years ago; you could actually see the door panel bow inward when the window was operated, and the inner door fiberglass panel was cracking in several places from the power window repeatedly flexing it, and some of the bolt holes were elongated.

    I made some 1/8" sheet aluminum brackets and spacers contoured with a jigsaw to fit within the recesses of the inner door panel's contours (and used the window mechanism bolts to anchor them to the fiberglass). Those brackets tied the various window mechanism attachment bolts together to stop the bowing, spread the force loads, and hopefully keep the panel from developing more cracks.

    I think that was back about 1982, long before I bought a digital camera and regrettably I didn't document the repair. I'm pretty sure I subsequently sold that car (I've owned 6 Avanti's over the years, and can't always remember what I did to which car).

  4. 84 to 86 Jeep Cherokee interchange nicely as I recall. Probably most Chrysler cars of that era used the same thing.

    I went through my power windows in my 73 and they've been working just fine since.

    Could you elaborate on those statements, please.

    1. What year Avanti's do those Jeep Cherokee motors interchange with? (if there's a substitute for the '63 through the 1970's PW motors, I'd like to kow that)

    2. What did "went through my power windows in my 73" consist of doing?

    Thanks,

    Wayne

  5. The 5th gen Camaro is HUGE, that would look like a Moo Moo on Tayor Swift ....

    Tom

    Tom, just for fun. I looked up the specs for Avanti and for current Camaro, and they aren't all that far apart:

    Avanti is 192.4" long, 70.3" wide, and 53.8" high

    5th gen Camaro (2010-15) is 190.5" long, 75.5" wide, and 54.2" high (extra width might allow length to fit OK)

    3rg gen Camaro (1982-87) is closer at 192.5" long, 72.8" wide, and 50.2" high (probably a better fit on Avanti than 5th gen, but either might work)

  6. Anyway... nobody locally seems at all interested in re-brazing the bung onto the tank. In lieu of not finding someone that can do it.... suggestions?

    Anyone having luck with JB Weld?

    Thx, Brad

    Is their concern that the tank could explode or is the tank just in a really corroded condition? Have you tried the local radiator repair shops?

    Seems to me there's not much danger if the tank is thoroughly cleaned (and perhaps coated internally), then turned upside down and filled with water before brazing the fitting back in,

  7. As I understand it, gelcoat is a way of sealing rough fiberglass surfaces to keep the glass fibers from breaking/working loose from the surface, particularly after panel repairs that necessitated cutting into the panel surface, to make a tough, smooth, solid surface for the paint to adhere to.

    I've not had personal experience with gelcoat, but it can be done in 2 ways: spray it as the first coat in the parts mold (after waxing the mold for hand-laid fiberglass parts) when the part is made, or spray it onto an existing bare fiberglass panel to seal it before painting. I don't think gelcoat is used in press-molded parts, only for hand-laid parts to give a smoother outer surface (since the mold is smooth, the gelcoat comes out smooth). If gelcoat is sprayed onto a fiberglass panel to seal it, it results in a somewhat rough surface and needs to be block-sanded smooth when it dries, before applying primer.

    I do not think either Corvettes or Avanti's had gelcoat applied to them by the factory (their panels were press-molded).

    http://www.corvetteactioncenter.com/forums/c1-and-c2-general-and-technical-discussion/44259-should-i-gelcoat-3.html

    http://www.corvetteforum.com/forums/c1-and-c2-corvettes/579905-gel-coat-do-i-need-to-worry-about-it.html

  8. The problem with Blake's paint system was not just the paint. The new body composition required a far longer time to allow chemical agents to come to the surface of the body and evaporate than the fiberglass they had been using.

    I thought I'd heard the '83 paint problem had been traced to oil leaking into the compressed-air system that fed the paint guns.

  9. I cannot claim any expertise in this area, but here are my thoughts...

    The rear axle in your Avanti is likely a Dana 44 unit. I doubt that the 56 Chevy used a Dana 44, and if it did, that it would simply bolt into an Avanti.

    (Dana is a company headquartered in Detroit that manufactured differentials for various auto makers, and the 44 is a design they probably supplied in various configurations... axle housing lengths, spline count, spring mounts, traction bar mounts, lug sizes, etc depending on the application, but the basic dimensions of the differential gearbox should be standard, I think).

    http://www.studebaker-info.org/text3/Dana3.txt

    http://forum.studebakerdriversclub.com/showthread.php?33130-Converting-a-Dana-44-to-PosiTrac

    http://www2.dana.com/pdf/X510-7.pdf

    http://www.aoai.org/forums/index.php?showtopic=306

    There are suppliers offering positraction units for Dana 44 axles...

    https://www.yukongear.com/PartsList.aspx?SearchMode=Diff&Type=Dana&DiffID=135&DiffName=Dana+44+Rear&CatID=38&CatName=Posi+%2F+Positractions

    http://www.nitro-gear.com/positractions/

    Or, it might be possible to find a dana 44 axle for another application (dunno if 1956 Chevy fills that bill) that can be adapted... chances are that the

    mounts and axle-axle width and axle length may differ from the Avanti.

    Your best bet might be to visit a shop that specializes in servicing differentials and see what they'd recommend.

  10. Some Bendix wheel cylinder kits came with the car but I am afraid that the cylinders are pitted. I haven't got there yet but was wondering how one would hone them smooth if the are pitted.

    A picture of the caliper showing cylinder/piston on each side attached.

    Sorry, Unfortunately I was not able to send picture as the file was too big.

    The single-piston systems in local parts stores are likely for later model Avanti's with Chevy chassis.

    The solution you choose will depend on your mechanical skills, or the willingness of a local mechanic to do the work.

    In my opinion honing is a job for a machine shop, and may or may not work, depending on the depth of the pits.

    Pitted cylinders can be re-sleeved with brass or stainless, but sleeving is about as expensive as buying new cylinder assemblies (probably around $500 or more for 4 cylinders, plus shipping).

    New wheel cylinders can be found (increasing in cost) in original, or a slightly larger diameter, or cast from stainless steel.

    Lastly, as stated by Avanti83, you can convert to a system that uses more modern components (probably near $1k in parts)

    http://www.applehydraulics.com/brakes.htm(call or email them for sleeving cost for the unusual Stude cylinders)

    http://www.studebakerswest.net/product.sc?productId=562&categoryId=76

    http://xks.com/i-7084309-gr-64932067-wheel-cylinder-2-1-8-new-assembly.html

    http://www.studebaker-info.org/steeltechinstall.html(but I don't think Steeltech still exists)

    http://www.turnerbrake.com/carkits.html

    As stated by Bob, SBCA96 has a nice front-brake conversion alternative, assuming he still offers it... he sells front brake brackets he designed, and specifies the parts that you have to purchase over-the-counter (rotors, calipers, hoses, etc); there is some machining required on the Stude hubs.

  11. I had a harness short some years back while on the road. I pulled off the freeway immediately, parked, and disconnected the battery as quickly as I could (turning off the ignition key did nothing). Several of my plastic engine harness tie-downs had deteriorated, broken, and allowed the harness to move forward.
    The main engine harness shorted where it passes behind the right hood hold-down lock, apparently from abrading against the hood lock housing until wires were bared and shorted to ground. Luckily I disconnected the battery before it fried anything beyond the firewall into the under-dash area. I was able to make repairs myself, but I now have a lot of splices in the wiring very near to where the harness exits from the firewall.

    I subsequently put a "green knob" switch on the negative battery cable (I think that's sufficient, but a cutoff switch on the positive terminal might be an even better precaution).

    So, warning to Avanti owners: check to see that your engine wiring harness is well-secured in areas where it passes near metal.

  12. I think I'm going to stick with my original assumptions, notwithstanding the eBay photo.

    From the tach:

    Black wire to ground, (can be attached to the sender's "Grnd: terminal, assuming "Grnd" already has a ground wire attached),

    Red wire to a power source active only with the ignition turned on (can be attached to the sender's "Batt" terminal if that

    terminal is already attached to power).

    Green wire to the sender "Tach" terminal.

    White wire to a power source for the instrument lights.

    From the sender:

    "Batt" to a power source active only with the ignition key turned on (use your own wire).

    "Grnd" to a chassis ground (use your own wire).

    "Ign" to the minus side of the coil (the terminal that is connected to the distributor)

    "Tach" terminal attaches the tach's green wire

    "Light" to a power source for the instrument lights, but only if the tach's white wire is attached here (I would not use this, I'd splice the white wire into a dash light wire).

    You might try contacting a speedometer/instrument repair business; they may have S/W wiring instructions for older tachs.

    ***********************************************************************************************************************************************

    PS, after posting the above, I did a couple more Google searches and one came up with the entry below, dated June 2000, which seems to bear out my assumptions (BTW, I converted my '71 to HEI some years back, and the Avanti (Stude round sender) coil wire worked fine on the HEI's tach terminal):

    ***

    Quote:

    "There are two models of the tach, a 970 for 12V negative grd and a 972 for 6v negative grd.

    There are only TWO senders a 990-A for various TRANSISTOR ignitions system and a 990-B for standard points type ignition. There is also a 4-6-8 cylinder connection inside the back of the tach.

    There is no reference to HEI systems as they did not show up for a few years.

    The hook up for the 990-A is between the amplifier and the coil in most of the variations given, as this was set up for various transistor and magnito ignitions available back then.

    The 990-B connects on the distributor side of the coil. The sender is clearly labelled with the only notation that the battery connection should go to a switched power source giving a full 12v, but not the radio circuit due to the possibility of interference. The light connection goes to instrument panel lights.

    The white wire from the tach goes to the light terminal on the sender, the Green to the Tach, the Black to the ground, the red to the battery.

    Don't know how this unit will work with a HEI dizzy, but sure would be interested in the results of connecting to the Tach lead of a HEI using the 990-B sender, You guessed it, that is the sender I have as well.

    I think these units are getting quite rare and may be next to impossible to obtain a different sender. I have send inquiries to SW re this unit with no reply."

    Unquote

  13. Hi Wayne. I sent you a PM with my e-mail address, but have not receive your screen print.

    Jim

    Jim, I sent 3 emails to your hotmail account yesterday in the 4:00 to 4:30 timeframe west coast time (forgot to put a link in one of them).

    I did not receive any indication from the internet that they could not be delivered.,, are you checking the right email account?

    Or did you give me a bad email address?

    Did you check your spam file (maybe they went into that for some reason).

    All I can suggest is that you give me your email address again.

  14. Jim, you've got me intrigued with this problem.

    I am going to call the Ignition Monitor the sender for brevity.

    I did some web searching and found a S/W tach & sender on an expired eBay listing with wires still attached to the sender; I think the sender was listed as the same number as yours. Unfortunately I can't find it again to give you a link to it, but I did do a screenprint of the sender as I was looking at it. The wires were rolled up together so it wasn't possible to tell where the far ends go, and the picture is very grainy. I enlarged it to better see the sender and labeled it... some colors can still be discerned. Maybe it will give you more clues, or verify what I said above.

    As usual, the screenprint, as small as it is, is too large to attach to this post, so if you want it, send me a PM with your email address.

    Here is what I think it shows:

    Place the sender on the table in front of you with the 2-terminal side to the left and the 3-terminal side to the right...

    The closest terminal on the left has a white wire and possibly a second wire (too dark to tell color and it might

    actually be a continuation of the dark wire attached to the middle terminal on the right);

    the terminal above it has a wire too dark to tell color (I suspect both those dark wires were added by the installer).

    The closest terminal on the right has 2 black wires on 1 connector (and possibly a thin wire, very difficult to see, may be tan or lt pink and

    go to the tach);

    the middle terminal has 2 red wires on 1 connector (and it looks like a third, black wire on it's own connector that appears to go to the

    tach. If so. that's weird);

    the furthest away has a light green wire.

  15. I don't think you can go too far wrong by dealing with the wires you know have to attach to certain terminals, and playing with the few remaining.

    If you take the chrome cover off the tach, you will likely find markings where the wires attach that give clues as to what they are; for example, one probably goes to the back of the light bulb socket, one simply attaches to the case (ground), one may say "tach" or "Ign", one may be "+" (12v power). Having done that, its possible some of my wire color assumptions below are incorrect, so revise my wire colors accordingly.

    I would assume that the Grnd terminal on the Ignition Monitor has to connect to a vehicle ground (use your own wire) and also that the black wire on the tach must attach to ground, easiest would be to attach it to the same Ignition Monitor ground terminal.

    I would assume that the Batt terminal on the Ignition Monitor has to connect to a chassis wire that is hot when the ignition key is on (use your own wire); the red wire on the tach is likely 12v power (hopefully you checked markings) and if so, easiest would be to attach it to that same Ignition Monitor Batt terminal.

    The Ign terminal on the Ignition Monitor has to attach to the tachometer terminal on an HEI distributor (upper one?), or for points systems, to the coil terminal on the distributor side of the coil (eg, same coil terminal that has a wire going to the distributor).

    That leaves white and green wires on the tach (for carrying the speed signal, and for the tach's light), and Light and Tach terminals on the Ignition Monitor... if you removed the tach cover, you'll know which wire is which.

    The light wire can simply be attached to the Batt terminal of the Ignition Monitor, but that means the light is on whenever the ignition is on... if that's problematic, you might want to tap into a vehicle wire that is only hot when the headlight switch is on, (like a wire to one of the instrument panel lights) not to the Ignition Monitor.

    Unless I missed something, that leaves only one wire, to be attached to the "Tach" terminal on the Ignition Monitor.

    No guarantees, but that's how I'd do it.

  16. <snip> We have the paint codes but they do not cross reference to an actual formula for the mix. Any suggestions?

    Do you have the paint chips for matching? Seems to me that someone used to sell the Avanti chips, but they are also available as chips from major paint makers on eBay and other sources.

    http://tinyurl.com/mdpvl5p

    However, if you are spotting-in a small repair area, your old paint has to be matched as it is likely faded from original.

  17. My guess is the brake booster is likely the reliable indicator, but is the master cylinder cap original to the M/C or did someone add that Dot 3 notice?

    If the M/C has been changed at some point, the cover may have come with that notice.

    Dot 5 should not harm a system designed for Dot 3. Either will work, but they cannot be mixed; the question is: what is currently in the system?

    Since brake fluids seem to change/lose color after awhile, the purple color of Dot 5 is probably no longer an indicator.

    Perhaps by taking a bit of fluid from the master and dribbling it onto a painted surface... Dot 3 will likely damage the paint if left on the surface a day or two. Dot 5 will not harm paint.

    From the internet: "Another way to tell between DOT3/4 and DOT5 is to put some of the fluid in a glass jar and add a few drops of water.

    Water will mix completely with the DOT3/4 but won’t mix and will remain as a separate blob in the DOT5."

    As for preference, I use Dot 5 in my Avanti's. If switching from Dot 3 to Dot 5, you should remove all remnants of Dot 3 with a thorough Dot 5 flush of the entire system. I made the switch on my '71 when I did a brake system rebuild and was replacing all 4 cylinders.

    BTW, what are "slugs"?

  18. Nice discussion between folks who have done it before, glad it worked out for you... the rest of us are left completely baffled because no pictures, no links to hardware, and very brief cryptic verbiage (and I consider myself mechanically-inclined).

    Bill, wish you'd have taken my prior comment to heart, I'd have liked to learn something about doing a swap from this thread, but I didn't. Opportunity missed.

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