[GMCnet] Brake fluids -Dot 5?

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Bob Dunahugh via Gmclist

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May 27, 2020, 2:17:21 AM5/27/20
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It depends on what you are doing to the system at this point. Plus. What are your interest in DOT 5. Each type of brake fluid. Have different attributes. For me. My GVW is sometimes at 24,000 lbs with our 78 Royale. So I install Ford's DOT3 High Performance brake fluid. ( Only at Ford dealers. ) That Ford put in their trucks. That were slated for MH use. As it's boiling point is much higher then standard DOT 3. The Feds have a minimum boiling point for DOT 3. That must be met. Ford,s is just way higher, I use it for my road racing. I have some photo's that were taken by a friend. Of my Yenko, at dusk. The drums were glowing. As I have segmented iron brake shoes. I change fluid everyday. Some like DOT 5. Because they feel it can be used for more years. All brake fluids should be changed every 5 years. On our GMC. Every 4 years. WHY. Because I love our Royale. And us.
Bob Dunahugh
78 Royale since 2003
4 COPO Yenkos
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tom geiger via Gmclist

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May 27, 2020, 11:29:37 AM5/27/20
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Thanks Bob for getting back. I had my brakes a couple of years ago and was thinking I needed to change out brake fluid here but looks like I have a
couple more years yet. The DOT 5 consideration was because of its higher boiling point and also its stability pertaining to water absorption. I
would like to check into Fords brake fluid when the time comes.

Thanks,
Tom

Emery Stora via Gmclist

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May 27, 2020, 12:47:00 PM5/27/20
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Tom
Check into5.1 it has as high a boiling point as 5.0 and has other advantages. I have now installed it in 6 GMC’s for friends

Emery Stora

> On May 27, 2020, at 9:29 AM, tom geiger via Gmclist <gmc...@list.gmcnet.org> wrote:
>
> Thanks Bob for getting back. I had my brakes a couple of years ago and was thinking I needed to change out brake fluid here but looks like I have a

Bob Dunahugh via Gmclist

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May 27, 2020, 12:52:47 PM5/27/20
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Tom. DOT min boiling point is 284 F (140 C ). Ford is 500 F (205 C) Water absorption was a big deal prior to about 1960 I believe. In that time frame. Systems became much more sealed. You see brake system that are 40 years old. And still have never been change. Brake lines rust from the outside. Some owners believe SS lines need to be installed for corrosion protection. Fine. As a note. SS lines are very hard. Thus getting them to seal at the brass fittings can be an issue. With standard steel lines. Those lines will out live you. Get those rubber brake hoses changed.
Bob Dunahugh
78 Royale since 2003
4 real COPO Yenkos

________________________________
From: Bob Dunahugh
Sent: Wednesday, May 27, 2020 1:16 AM
To: gmc...@list.gmcnet.org <gmc...@list.gmcnet.org>
Subject: Brake fluids -Dot 5?

Todd Sullivan via Gmclist

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May 27, 2020, 1:35:10 PM5/27/20
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What Emery said. Since the introduction of 5.1 5.0 has no real benefit but
brings more hassle.

Sully
Bellevue wa.

Matt Colie via Gmclist

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May 28, 2020, 3:14:59 PM5/28/20
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In the early days of DOT5, I converted several antique and classic vehicles to it. Because an automotive chemist friend (I had not yet met Emery)
told me about the material incompatability, because elastomers all have some permeability of lots of things and it can be cumulative he suggested that
I not change, but convert the system by replacing all the elasomer (like rubber) parts. I did that on some, but not all. Those where I did not
replace everything turned out to be leaking and terrible things in later years. This was only cured by rebuilding the entire system.

Also in later years, one vehicle that I did keep for myself had wheel cylinder trouble. I found a line of rust in the bottom of some wheel cylinders.
Again, my ties with the automotive engineering world got me a lot of information. It turns out that the hydraulic seals used in automotive breaks
are all about keeping the hydraulic fluid in (surprise?) but in doing that, they are not great at keeping water out. Before a hydraulic fluid with
near zero miscibility for water came along, this was no big issue. Water got in, but nobody really knew how that happened. It is why GM went to the
diaphragm sealed master cylinder.

Now, with DOT5, the water could be sequestered in the wheel cylinders and there was nothing to prevent local corrosion. This is why you should think
about flushing the brakes of a long lived vehicle. It is the only way to prevent expensive damage.

Speaking of expensive, one of those vehicles with a rusted wheel cylinder was an strange and the wheel cylinders by part number were NLA. I now
needed two. The two were different. I had to get something that was close to one and remachine the mounting so it could bolt to the backing plate and
then rebore it to the correct size. Fortunately a rebuild kit was available. The other I put a SS sleave in. Being able to buy new wheel cylinders
is so nice.

I now have a "Guess the moisture" probe that I get out when doing a vehicle service. I have not had it long enough to venture an opinion as to its
value.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit

James Hupy via Gmclist

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May 28, 2020, 7:22:12 PM5/28/20
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First British car I worked on with Girling Disc brakes, was a Triumph
roadster, a TR-2 if memory serves. Those brakes used Mineral Oil as brake
fluid. This one was leaking from every place possible, and the owner wanted
it fixed. He was a purist, and fussed over every detail. He wanted it ALL
ORIGINAL. I told him if he insisted on using that Girling fluid, that he
could load it up and take it down the road. He went to a local BMC repair
shop, and they quoted him some unbelievable price to fix his brakes. So, he
came back and asked what we could do to fix his brakes. I checked with my
local supplier, and every rubber part in that system was available from
Lockheed in modern D.O.T. 3 compatible stuff. So that is what we did.
Rebuilt every part of that system. I personally think it worked better than
the Girling stuff, a whole lot cheaper, too. Your experience may differ.
Jim Hupy
Salem, Oregon

Johnny Bridges via Gmclist

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May 29, 2020, 12:04:05 PM5/29/20
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After three Bugeyes and one Spridget, I found something nice to say about British brakes. They don't fail as often as Lucas electrics.

--johnny

--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell

Johnny Bridges via Gmclist

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May 29, 2020, 12:11:16 PM5/29/20
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Emery, am I correct that I can replace the 3.0 with 5.1 on my coach without worrying about incompatibility? I don't want to take it apart again if I
can help it. Three years ago I did rear cylinders and shoes, it had newer lines and good drums. Recently I put 80 MM calipers and lines on the
front. And I wonder if I'm bleeding them properly. I've a borrowed Hupy bleeder, how much fluid should I run through to be reasonably sure I have
the air out? I also wonder if I'm adjusting them too loosely? Wouldn't matter ona tandem but with four sets, you could run out of pedal before you
run into the drums. I feel like either they're too far out or theree's air in the system. When it hits the discs about halfway down, it's solid.

--johnny

--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell


Todd Sullivan via Gmclist

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May 29, 2020, 12:26:04 PM5/29/20
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5.1/3/4 all compatible.

Sully
Bellevue wa

Emery Stora via Gmclist

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May 29, 2020, 1:03:44 PM5/29/20
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Yes, 5.1 is completely compatible with your existing fluid.

Suck the brake fluid from th master cylinder and fill with Dot 5.1. Open the right rear bleeder. You can see if it will gravity bleed. Be sure to use a clear tube from the bleeder to the collection bottle so you can see air bubbles. If the fluid runs clear go to the other brake on that side. If they won’t gravity bleed use a bleeder or have someone push on the brakes. I prefer to use a vacuum bleeder.

Then bleed the right side, then the right front and last the left front. It shouldn’t take more than 1 to 1-1/2 pints.
The amount of clearance on the shoes shouldn’t reale to air in the system. Turn the adjusting “stars” while turning the wheel until you just feel a drag.

Emery Stora
77 Kingsley
Frederick CO

> On May 29, 2020, at 10:11 AM, Johnny Bridges via Gmclist <gmc...@list.gmcnet.org> wrote:
>
> solid.
>
> --johnny

John Wright via Gmclist

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May 29, 2020, 1:19:27 PM5/29/20
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The Dot 3, 4 and 5.1 are all compatible with each other. I have only know of 1 person that ran the Dot 5 silicon fluid in his brake system and that was Don Wirth who many of you knew from days gone by. Dot 5 does not absorb water, but will allow it to collect in your brake system after a while. It is an absolute pain in the butt to change over to. Requires that all the rubber parts be rated for the silicone brake fluid and typically you end up changing all the rubber out, replacing all the slave cylinders and or calipers out for new and flushing and drying all the brake lines and oh yes you will need to change the combo valve too. Too much pain for so little gain!

I have run for the last 20 years run a Dot 3/4 brake fluid. I have been using the Valvoline synthetic Dot 3 & 4 Brake fluid without any issues.

https://shop.advanceautoparts.com/p/valvoline-dot-3-and-4-brake-fluid-12-oz.-601457/89016680-P?searchTerm=brake%20fluid

I thoroughly check my brake system every year and flush every 2 years. It usually takes about 2 of the large bottles (32 oz) to do it correctly and I use a vacuum bleeder to finish and start out just doing a gravity bleed first to get the majority of the air out of the systems. Always start at the farthest away brake and work your way to the closes to the Master.

I will be changing to the Wagner Dot 5.1 Severe Duty Brake Fluid this summer as I will have time to do a number of maintenance and small projects with the coach parked.

Advanced Autoparts:
<https://www.powersportsid.com/wagner/dot-5-1-brake-fluid-mpn-fc133301.html?view=429306&utm_source=microsoft&utm_medium=cpc&utm_campaign=268680876&utm_content=1176478073060724>
or Amazon:
<https://www.amazon.com/Wagner-Dot-SEVEREDUTY-Brake-Fluid/dp/B000C92RDC/ref=asc_df_B000C92RDC/?tag=bingshoppinga-20&linkCode=df0&hvadid=&hvpos=&hvnetw=o&hvrand=&hvpone=&hvptwo=&hvqmt=e&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=&hvtargid=pla-4584413737342657&psc=1>

J.R. Wright
GMC Great Laker MHC
GMCGL Tech Editor
GMC Eastern States Charter Member
GMCMI
78 GMC Buskirk 29.5’ Stretch
75 GMC Avion (Under Reconstruction)
Michigan

tom geiger via Gmclist

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May 29, 2020, 2:03:11 PM5/29/20
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How funny Jim H. The car I mention I got the Dot 5 suggest on their forum was a Triumph TR6. The brakes are the last item from the winter list I had
to do. And of course they are giving me the most trouble. Once I get it flushed then I’ll be ready to drop it back on its feet again.
Dot 3 is what I decided to go with so I think I’m close with that. Too funny on the Lockheed reference too. Had work with them for a extended
period at the engineering firm I worked at. Small world kinda.

Tom

James Hupy via Gmclist

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May 29, 2020, 4:07:12 PM5/29/20
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Early British cars ( before 1972) had the Prince of darkness ( Lucas )
Electrical systems, and Mineral Oil Brake fluid. Then came US regulations
on emissions and Low speed crash resistance. Beautiful "nerf" style bumpers
went away, and "crash resistant" Butt Ugly telescoping bumpers were hacked
on, raised the price as well as the weight. Mineral Oil brake fluid gave
way to D.O.T. 3. Roll over protection, safety "A" pillars, and Emission
equipment taxed those British and other European cars right out of the
export business. Only the strong survived. AUDI, VW, VOLVO, etc.
The Japanese were lying in the weeds just watching. They went back to
the drawing boards, and the Tonka Trucks like the Little Hustler
disappeared, and VERY HIGH QUALITY autos came on the market. They are still
here. Just the way it is, I guess.
Jim Hupy
Salem, Oregon

Hal StClair via Gmclist

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May 30, 2020, 9:12:19 PM5/30/20
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There's a reason the Brits drink warm beer, Lucas refrigerators :lol: :lol:

--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM

6cuda6--- via Gmclist

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May 31, 2020, 2:12:31 PM5/31/20
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I used Dot 5 in all my road race motorcycles....key word "race"....all fluids changed every week after a weekend of racing.
RV or Motorhome .... slow and leisurely.... all fluids changed maybe once a year therefore DOT 3/4/5.1.

Race bike = trailer full of spares....lots of DOT 5 in the cabinet.
Motorhome = Gas stations, Walmarts, truck stops etc.....not a common place to find DOT 5 fluid.

If you still want to run DOT 5 you better have enough in your RV as spare if something goes wrong and be willing to change it ALOT.
Biggest everyday bonus with Dot 5...wont strip your paint if you spill some on it :d
--
Rich Mondor,

Brockville, ON

77 Hughes 2600

Johnny Bridges via Gmclist

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May 31, 2020, 6:46:58 PM5/31/20
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You ever come south and run Road Atlanta?

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell


6cuda6--- via Gmclist

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May 31, 2020, 6:52:59 PM5/31/20
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Use to before i retired from racing a while back.....crashing just hurts to much when you get older...lol.

Johnny Bridges wrote on Sun, 31 May 2020 18:46
> You ever come south and run Road Atlanta?
>
> --johnny


--
Rich Mondor,

Brockville, ON

77 Hughes 2600

Dave King via Gmclist

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May 31, 2020, 9:43:32 PM5/31/20
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Rich, did you ever race at Mosport or Shannonville ?@?
I pwas in the first ever car race at Shannonville when John Nelson owned it.
I we end up having a car race at Shannonville this year I'll let you know. I'm the
Regional Chief of Scrutieering for CASC.
--
DAVE KING
lurker, wannabe
Toronto, Ontario, Canada

James Hupy via Gmclist

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May 31, 2020, 10:15:46 PM5/31/20
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Being a Journeyman Small Engine Mechanic via apprenticeship, I had a big
interest in high performance small engines. Everything from hot rod
chainsaw competitions, and very, very fast outboard hydroplanes, racing
motorcycles, ( like the Mike Hailwood 6 cylinder 250 cc.and 350 cc Hondas.
Wow, dual overhead cam, 4 valves per cylinder, 6 carbs, waaaaay over square
engines that came on the cams about 17,500 rpms, and redlined at 23,500
rpms. Those things sounded like banshees screaming at full song. God, those
things were beyond scary fast.
Lastly, came go-carts. Both 4 cycle and 2 cycle. Imagine, if you will, an
engine that had the displacement of 2 salt shakers. (100 cc.) that produced
over 40 horsepower. Put that engine, or two of them on a competition
tubular frame that weighed less than 100 pounds. Add a 130 pound fearless
rider/driver, and you have a combination capable of well over 100 mph. In
fact, on the short course at Portland International Raceway, the single lap
record is quicker by a go-cart, than a D production Corvette. I used to be
stupid enough to race those carts. But, I gave away too much height and
weight to be truly competitive. I was a much better race mechanic, and
could tweak every bit of hidden horsepower out of those things. Lots of
fun, and memories too. If anyone remembers the Sneva's from Eastern
Washington state, Indy car champions, they started out with go carts. They
were awesome fast.
Jim Hupy
Salem, Oregon

On Sun, May 31, 2020, 6:43 PM Dave King via Gmclist <gmc...@list.gmcnet.org>
wrote:

Johnny Bridges via Gmclist

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Jun 1, 2020, 8:14:45 AM6/1/20
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The leading two engine sounds was/is Hailwood lapping Talladega on the high bank and a round motor making takeoff power - Corky Fornoff's Bearcat was
an excellent example. Anyone gets back to Road Atlanta or the kart track across the highway let me know. It's a decent slingshot shot from my
backyard.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell


James Hupy via Gmclist

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Jun 1, 2020, 10:39:12 AM6/1/20
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I spent a couple of weeks when I was 15 or so visiting my aunt and "new"
uncle (she was married 5 times) in Wenatchee, Wa. where he was employed as
a crop duster pilot. He was former WW 2 fighter pilot, and as wild as they
come. He dragged me out to the Wenatchee Airport with him, and introduced
me to round motors in fabric covered biplanes. Mostly Stearmans, but a
couple of other brands were there also.
5, 7, 9 cylinder round motors on 120 octane av-gas first thing in the
early dawn. I still have fond memories of those 2 weeks. They had a jump
seat that clipped into the dust hopper of a 450 stearman duster. My Uncle
Al gave me a ride in that thing I will never forget. I absolutely loved
every second of it.
Not scared, but it was one of my first experiences with an adrenaline
rush. Metal taste in the mouth, uncontrollable shakes, non stop jabbering.
The whole deal. From that time on I have always had a love of all things
aviation. Even started an I.C.S. course in learning how to fly. But
somewhere in there I learned about girls. Nuff said.
Jim Hupy
Salem, Oregon

tom geiger via Gmclist

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Jun 1, 2020, 5:49:53 PM6/1/20
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Well my first experience in a airplane was no where as cool as yours Jim but was as impressionable and memorable as well. I was 13 and a buddy of
mine’s dad had a high wing BeachCraft that he took me and his son for a ride I’ll never forget. Something with you climbing straight up till you
stall and cutting the engine and seeing the prop slowly turning and then as you do on the first hill on a rollercoaster roll on over and do the death
dive certainly stopped my heart for a sec and sufficiently loaded my pants. Never saw his dad laugh si hard when I squealed like a 12 year old girl.
Which seeing him laugh si hard in our situation had its own chilling effect at the time. Anyhow, will never forget that one.

TG

PS: never would thought a Beachcraft highwing could do those kind of things!

James Hupy via Gmclist

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Jun 1, 2020, 5:58:00 PM6/1/20
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One of my good friends recently died. He lived at the Independence, Oregon
Airpark. He left his widow a Beautifully restored certified for flight
Stagger Wing Beech. His widow had an offer of 400 K for it. I looked into
their value, and ones the caliber of this plane mostly sell for upwards of
1 million. I told her to shop around more for a better offer.
Jim Hupy
Salem, Oregon

On Mon, Jun 1, 2020, 2:49 PM tom geiger via Gmclist <gmc...@list.gmcnet.org>
wrote:

> Well my first experience in a airplane was no where as cool as yours Jim

D C _Mac_ Macdonald via Gmclist

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Jun 1, 2020, 6:09:36 PM6/1/20
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She should probably get some help from her husband's buddies to
advertise it properly. Aero Trader or Trade-a-Plane come to mind.

D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com
________________________________
From: Gmclist <gmclist...@list.gmcnet.org> on behalf of James Hupy via Gmclist <gmc...@list.gmcnet.org>
Sent: Monday, June 1, 2020 17:03
To: gmc...@list.gmcnet.org <gmc...@list.gmcnet.org>
Cc: James Hupy <james...@gmail.com>
Subject: Re: [GMCnet] Brake fluids -Dot 5?
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