What have you done to your square lately??

Goldie Driver

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Had to unhang the brakes again today - apparently it was not the master cylinder causing that but the proportional valve.

Which means the new AC Delco master cylinder earlier this month was just more practice.

:confused:

The pedal literally hung on me at a stop sign this morning- I had to undo the nuts holding the master cylinder to the booster.

Once I got far enough off the booster I heard a bang and felt the front of the truck shake as the valve released.

Hasn't done it again all day, and I had done a good gravity bleed on all 4 last Sunday. Maybe I flushed some crud loose - who knows.

@Flatwater - I would not rule out that prop valve on yours.

The only replacement I know of, though, is Chinesium off the internet- Fleabay or Amortizeon...

I think I went with the latter but due to 5 flare fittings have not installed it yet.

Those fittings, especially on this truck, scare me. o_O



Best of luck.
 

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59840Surfer

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More news ....

I had posted this:

Now with the rear spacers I feel the u-joints buzzing at roadspeed and a certain "flip-flop" at start up. They are tapered to help point the pinion toward the transfer case --- but maybe not enough huh?

Is there a CV conversion ever done on the rear driveshaft?
Should I just add some tapers to point the pinion even higher?

Can "normal" u-joints survive this sortta changed running angle?\

.... and although the company that makes the spacers says they are supposed to be installed the way they are (small tapers to the rear to point the pinion higher - AT the transfer case ...

There's a site that says they should either be flat or reverse them to put the pinion lower so the angle on the u-joints are equal.

IOW --- it you have a 10° angle on the front of the driveshaft, then you need to have the same angle on the part of the driveshaft at the pinion too.

I watched a video on it --- and although I haven't mad4 that "correction yet (if that's what to call it) but I'll try to get out in between snowstorms in the next few days and try it.

Here's a video - not by me ---> Thoughts?

xc_hide_links_from_guests_guests_error_hide_media
 

59840Surfer

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Found it. It sits at 12 o'clock, under and behind the water pump. This is not going to be easy to check timing. My only question is what is the round thing,that looks like it holds a pencil, for?

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That's the monolithic probe hole.

It is a magnetic pickup, cylindrical and on a flex that measures the timing after you also capture the #1 cylinder fire on the plug wire with an inductive pickup.
I still have my mono-probe and my Snap-On timing light that can perform that process.

Although I also owned an Allen Scope --- the Autoscan and Snap-On scopes had monoli6thic probes too --- Snap-On had one that worked with their timing light as a stand-alone device.

I even still have my Snap-On Diesel Timing Meter, that also used the mono-probe and a dual-folded meter bank with RPM and TIMING readouts.

So --- monolithic timing probes were not all that rare and on some engine installations were the only way to read the timing marks.
☼ Chevy Vans and motorhome conversions were very hard to read even if you had the stand-out water pump on it --- which only some of the van conversions had.
☼ GM had no idea where a lot of those van cabs would wind up, and they didn't put the stand-out water pumps on them --- not all the time, anyway.
 
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59840Surfer

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Yup. Slight resistance/drag.
I can't find where your problem/post started --- and I see that you're fighting your brakes and you've tried everything .... let me ask a question though --- tell me if you've answered it already --- OK?

Did you change your master cylinder?

What I'll offer next will be contingent upon your answer ....
 

CalSgt

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More news ....

I had posted this:



.... and although the company that makes the spacers says they are supposed to be installed the way they are (small tapers to the rear to point the pinion higher - AT the transfer case ...

There's a site that says they should either be flat or reverse them to put the pinion lower so the angle on the u-joints are equal.

IOW --- it you have a 10° angle on the front of the driveshaft, then you need to have the same angle on the part of the driveshaft at the pinion too.

I watched a video on it --- and although I haven't mad4 that "correction yet (if that's what to call it) but I'll try to get out in between snowstorms in the next few days and try it.

Here's a video - not by me ---> Thoughts?

xc_hide_links_from_guests_guests_error_hide_media
Didn't watch the video but...

With a standard driveline (one u-joint at each end) the joints need to be "In phase", meaning the trans tail shaft is parallel to the pinion. If you lower the tail of the trans, raise the pinion and visa versa.

With a double cardan (CV at the trans and single u-joint at the pinion) the trans sits at whatever angle it needs to, and the pinion would point almost directly at the trans tail shaft. This puts the face of the pinion flange or yoke ears 90% off of the angle of the driveshaft tube. Some people calculate for a little axle wrap under acceleration into the equation and subtract a degree at the pinion.

A cheap angle finder with a magnet is helpful for figuring this out...

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59840Surfer

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Didn't watch the video but...

With a standard driveline (one u-joint at each end) the joints need to be "In phase", meaning the trans tail shaft is parallel to the pinion. If you lower the tail of the trans, raise the pinion and visa versa.

With a double cardan (CV at the trans and single u-joint at the pinion) the trans sits at whatever angle it needs to, and the pinion would point almost directly at the trans tail shaft. This puts the face of the pinion flange or yoke ears 90% off of the angle of the driveshaft tube. Some people calculate for a little axle wrap under acceleration into the equation and subtract a degree at the pinion.

A cheap angle finder with a magnet is helpful for figuring this out...

You must be registered for see images attach
That's the gist of it --- the angles should be equal or the pinion can be a degree or so below parallel anticipating spring-wrap.

But anything over 10° in the u-joint-to-flange is creating a potential catastrophe in that the angle is too severe for the u-joints to handle for long --- if very much at all really.

I don't actually know the included, cast-in angle in the new spacers, but it is significant! A guess might be 8° or 10° - and that may be the big problem here.

I think I'll reverse that angle and perhaps get some 2° - 4° shims to fine tune things later on.

Right now --- I'll have to use cardboard and layered clothes to work in a snowbank.
 

CalSgt

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That's the gist of it --- the angles should be equal or the pinion can be a degree or so below parallel anticipating spring-wrap.

But anything over 10° in the u-joint-to-flange is creating a potential catastrophe in that the angle is too severe for the u-joints to handle for long --- if very much at all really.

I don't actually know the included, cast-in angle in the new spacers, but it is significant! A guess might be 8° or 10° - and that may be the big problem here.

I think I'll reverse that angle and perhaps get some 2° - 4° shims to fine tune things later on.

Right now --- I'll have to use cardboard and layered clothes to work in a snowbank.
Good luck… I’ve been there before
 

Ontheboulder

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getting it together,slowly!! painted the door panels a charcoal gray,then a light gray suede on the inserts!! The floor mat turned out pretty good too!!
 

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Grit dog

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getting it together,slowly!! painted the door panels a charcoal gray,then a light gray suede on the inserts!! The floor mat turned out pretty good too!!
Coming along nicely. Door panels look sweet. Is your truck a twin to mine too? Interior looks the same.
 

Ontheboulder

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Coming along nicely. Door panels look sweet. Is your truck a twin to mine too? Interior looks the same.
pretty much, original blue and charcoal gray with the blue interior. gonna leave the blue paint but change to the charcoal upholestry with some light gray in the inserts and on the bottom of the door. gonna do the headliner in light gray as well
 

Grit dog

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Got the new dash in, window trim and everything buttoned up.
I think it fits pretty darn good. Was nervous with all the stories about cutting stuff n stuff. Lol
Looks just slightly goofy around the gauge bezel in the top corners but everything fits.
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Stereo cut out looks like someone literally chewed through the dash with their teeth…. The offending cuts and edges suspiciously match tin snips, lol.
 

Big Ray

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Problem is, I still ain’t got ‘em! Short of monkeying around with the proportioning valve, everything has been touched. Finally have a good pedal feel, just no stopping. ‍♂️. I dunno. It’s cold, I’m pissed off. Going in the house to pout.
How old are the rubber hoses?
The rot internally, swelling up and preventing pressure buildup.

Sometimes pieces break off, gumming up the works so to speak.
 
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