The Mack Worth

[mrsmackpaul]

Not sure if I have shared this before but I find it a really good read 

not my story this is as written by Bill Moline 

John Victor Ehret taught me to drive a truck. He taught me on Jackbilt No.2 an L model 190 with a silly wheel pusher, Clark 5 speed and 2 reverse gearbox and powered by a 6/71 GM and put on the ground by a No.4 Eaton diff. At various times it had had different motors but the current one in 1963 was the 6/71. It had big shoulders that truck, but skinny legs, and axle changing was part of the job description. Previous Jackbilts had included a KB6 which went through various transformations and finished up with only the cab and chassis being original. After the 90 came the Mercedes, bought one night on his way home from the pub. He had paused to urinate and leaned on the mudguard to steady himself and noticed the huge hole where the engine had been. He reckoned a 671 would fit nicely and he happened to know where there was one doing nothing so bought the Mercedes on the spot from the owner who was asleep on the seat. Ehret had a thing about 2 strokes and superchargers. This came from his motorcycle racing days. He had built a supercharged 2 stroke racing bike that nothing could get near and I think he caught the GM disease from that. The engine that he had in mind for this lorry had probably worn out a couple of tanks, a saw mill or two, and the pump to which it was now attached but it would have fitted the No.1 Ehret criteria nicely. IT WOULD HAVE BEEN CHEAP. Well over a period of 2 or 3 years he would work on it when home or when he had a driver on the 90 and it gradually took shape. Mercedes cab chassis, NR Mack steering axle, B43 Mack drive axle, BPW dual wheel pusher, La France radiator that had cooled a V16 flathead Lincoln engine, a strange 5 speed full synchromesh gearbox that came with it and for which he had a spare, purchased brand new from Tutt Bryant for 5 pounds because they didn’t know what it was. The joey box out of Billy Game’s beaver was on the end of the other stick in a direct and under configuration as the direct and over side of the gears was worn out. I drove this for Jack but the continual blow ups by the antique 671 broke my heart and I left to drive a B model for pommy Reg Ward, one of the Elson gang of thieves. The trip after I left it blew up seven times between Rockhampton and Perth, so it wasn’t me after all. Jack never said it was but I had the guilt's pretty badly I can tell you. While self and Cold Cans (Mick Jacobson or Stubby Mick as he was known) were driving the Mercedes Jack was hard at work on the Mackworth. He had bought a rolled over NR from up round Grafton way with a, wait for it, 2 valve 6/71 in it, all his GM’s were 2 valves, a duplex box and not much else. This was going to be, he said, the be all and end all of Jackbilts and it was. His original idea was to buy an ACCO cab and cut it into quarters and extend it to be KW or Pete size. One day on his was to or from the Town and Country (where the atmosphere is great) he drove past Kenworths and spotted Tony Harbutts burnt out cab over cab. Next morning he was on the doorstep at daylight, about 10.30am, (Jack was not an early riser) and purchased it on the spot.

Jack built number 3, Merecedes, about 28 ton of wheat payload hanging off  Mt Tomah or Mt Victoria waiting for the road to dry out so I could get traction 

 

Rolling in a set of bearings near Cassillis

 

He mounted it on the chassis using plummer blocks and a bit of 1” round bar and proceeded to build the
Mackworth. The first big job was to burn all the rivets out of the chassis and replace them with machine
bolts in reamed holes because over the years most of the rivets had worked loose. That took about a
month as I remember. I was still driving the Mercedes at the time and when I was home assisting with
the build. Next came the rear cab mounts and the cab lifting mechanism. The cab lifter was a boat winch
mounted on a bracket with the wire going down under a pipe mounted under the back of the cab, when
you wound it up the cab came up until the point of balance and then you let it down until the sun visor
touched the ground. Easy to work on that lorry. That was only part of the thinking however, the main reason
for the design was that you could buy a bit of cloths line wire and a boat winch anywhere for less
than $20, a huge saving on Kenworth’s hydraulic system.
The cab now needed to be made habitable so work commenced at speed. Jack did not entirely approve of
KW’s stressed skin construction and made a framework of heavy wall 1” by 1” RHS. Gradually it took
shape. From time to time specialist parts were required such as headlamp surrounds. Jack would go off
to St Peters and price these, recoil in horror at the quoted price, and announce for all to hear. “You could
hack one of them out of a solid lump with a blunt chisel and a hammer for less than that!” Progress was
stalled for a while when it came to the corners of the cab roof. Jack had sheeted the cab from side to
side and then front to back with a small overlap. This left a gap to be covered full of compound bends.
Jack always said the minute you become emotionally involved in the job it turns to s**t. You should leave
it be and do something else while the answer come to you. Whilst urinating behind the slowly emerging
Mackworth some time later he spotted the NR radiator cowl, now surplus to requirements, but full of
compound bends as required, another problem solved by ignoring it for a while.
Some things did beat him though. The insurmountable stumbling block, even for John Victor, was the
doors. Time for some lateral thinking. At KW at St Peters was employed at the time, and later at Lansvale
,a bloke in the workshop, whose name I can’t remember, who liked a punt, on anybloodything. Jack
cultivated this weakness and always went up on Mondays to make any purchase and commiserate with
or celebrate with this gent depending on how his weekend had gone. This bloke did the crash repair
quotes and gradually, in return for small cash “borrers” on bad Mondays, Jack was able to get him to
write bits and pieces off that otherwise may have been repaired.
I remember the day he got the driver’s side door. “Where did you get that”? I asked him. “From the good
fairy” he said , and the name stuck. The good fairy supplied a lot of little bits and pieces and Jack was
allowed to climb all over cabs at St Peters and make measurements to assist with his cab. I should point
out that the yard he built this truck in was next door to Mayne Nickless in Burrows Rd. in Alexandria so it
was not far to KW St Peters.

 

the begging the Mack NR turns up in the yard 

One thing The Good Fairy could not supply was a windscreen surround because they were either perfect or destroyed, so Jack
made one out of aluminium. When it was finished he went to KW St Peters to buy the windscreens, they told him to get
O’Briens to cut and fit screens because standard ones probably wouldn’t fit the frame he had made. Jack said his frame was
the same as theirs only better. They said if the screens fitted he could have them for nothing, and the rubbers as well. Jack
bought the screens, O’Briens were rung, the screens fitted, Jack got a refund.
Things were going swimmingly now, paint jobs were being thought about, the driver’s seat out of Blair and Reiber’s V8 Pete
was installed, it had been “saved” some time earlier. An electrician had been called in to wire it up, vents fitted to the front of
the cab but O worry worry there were no door frames and no passenger’s door. The passenger’s door didn’t worry Jack, a plywood
one would do, but the door frames were a must. It seems the only way to get a door frame was to buy a door and not
even the good fairy could arrange this.
Jack tried to buy some of the extrusion that the frames were made from but as the dies were owned by Paccar the aluminium
mob wouldn’t sell it to him. So he made his own extrusion by welding available extrusions together and then bending and polishing
them. He then appeared at St Peters with a carefully prepared off cut which he left lying about in the ute. This was noticed
by the good fairy as they yarned over the back of the ute and he asked where Jack had got it from. Jack said “You get me
a passenger’s door and I’ll tell you” A passengers door arrived very quickly and Jack took up the original extrusions, a partially
welded one, and the finished article. KW were gobsmacked and offered him a job as an advisor. Jack declined.
Next was the long anticipated test drive. A set of plates were attached, the mighty? 6/71 fired up and with a cab full of admirers
and hangers on up she went to Yellow Express and back. I wasn’t there but witnesses reckoned you could hear the gearbox
howling on the North Shore. Next came the only mistake he made with that lorry, an underspected bushranger that he got
from Bernie’s in exchange for the L Model 90. He kept replacing this box for the life of the truck. It wore out three housings
but he never upgraded it. It was a double overdrive box and the dear old thing would do about 70 mph. on level ground empty.

the cab mounted up

 

 

At long last it was finished and all that was required was registration. For this it had to go over the pits. I asked Jack how he
ever got it through. Well he said, no one will take a bribe if you cold cock them, and I never had time to cultivate a DMR inspector
so I hit on the idea of him being a betting man. Everyone likes to think of themselves as a risk taker in some form or
another so off I went to Fivedock and bet the inspector $50 it wouldn’t pass muster. You wouldn’t believe it. I lost my bet.
The lorry then went to work on the Gidgealpa pipeline job in SA and pulled a jinker for Brambles. Jack teamed up with Eddie
Stephenson? a bloke who was driving a Mack for Arthur Shoemaker and together, by overloading to buggery, and travelling
together, very slowly, on drive tyres they salvaged from Brambles dump and ran at 40 psi, and often chained or stiff bared together
they carried as much or more than most on that job and did a minimum of damage..
When the job cut out Jack got Champions to completely rebuild the rear end and fit higher ratio diffs and away she went on
interstate.
By this time the antique screamer was beyond repair so Jack did something he had not done since 1954. He bought something
new, and therefore untested. He hated untested things. In 1954 he had bought a new Commer . It was a blown two stroke . He
couldn’t help himself. To the end of his days if the word Commer came up he would correct the speaker saying that the correct
pronunciation was Coma. You had to be in one to buy one he reckoned.
The thing he bought new this time was a 290 Custom Torque Cummins. He went in to order a 335 but the smooth talking
salesman spun him a line about the 290 and he bought it. There was one condition. It had to pull 45 tons up Colo River at 15
mph or better. This was guaranteed by the Cummins bloke. I’ll bet he was sorry about that. It wouldn’t. It was not until Jack
told them to take it out and tow the chassis down to Detroit's to get an 8/71 fitted that they did anything about it except point
out that legal gross weight was 32 tons. Anyway they finally got it going to his satisfaction and it worked hard and long until
Dennis wrote it off in the territory.
Jack carted to Mt Isa and Gunpowder with it in road-train configuration. For some time the loading was crusher balls. He used
to put about 30 tons on each trailer and given that everything was super hefty in construction, from the bulbar to the tailght
the train probably tared about 30-35 tons. This gave him a gross of 90-100 tons. One trip he came upon Smiler (Frank) Nilon
broken down at Boulia, Smiler was good for about 100 tons too. Jack put a stiff bar on him and pulled him into the Isa. They
could only travel at night as the oil boiled in the diffs in daylight after about 45 minutes.
Two hundred tons gross is probably a record for a truck that was already 30 years old and had been designed as a tank carrier
for one tank.

Taken in Kenworth St Peters Sydney Workshop Circa 1975/6

 

 

Anyway a good yarn from a different time, a time sadly I dont think we will ever see again 
full credit to the author of the story and  and to people that have provided the photos 

Paul

 

[j hancock]

Everyday was an adventure!

[carlotpilot]

WOW

[Vladislav]

That's a really cool story!

Paulk, thank you for posting it on here.

I sure saw those images on the net since they were NR-related but haven't read the article.

[Swishy]

Gr8 info Mrs

here B a newer V:

az posted a cupla years ago

Clikity .......................ClikClikClik

 

cya

 

§wishy

[mrsmackpaul]

came across another image on FB of this truck the other day

dunno how they link is gunna work to FB but time will tell 

bit of a bugger not been able to upload photos no more as I reckon things are far more enjoyable to and easier to read with a yarn and pic or two to help tell the story 

 

Paul

 

 

[29Bowtie]

What a great adventurous tale these old trucks live. Thanks for sharing the story.

[JoeH]

Anyone notice the guy working on the crank is wearing flip flops?

[mrsmackpaul]

Yep sure did 

You blokes call them flip flops, we call them thongs or pluggers, Kiwis call them jandles ???

 

And pluggers were and still very common foot wear among a lot of working class people as standard foot ware 

I was in them today and have spent most of my working life in them 

 

Paul 

[Outbehindthebarn]

On 12/16/2018 at 7:19 AM, mrsmackpaul said:

Yep sure did 

You blokes call them flip flops, we call them thongs or pluggers, Kiwis call them jandles ???

 

And pluggers were and still very common foot wear among a lot of working class people as standard foot ware 

I was in them today and have spent most of my working life in them 

 

Paul 

I have some very hip Brazilian Havaianas, everyone wears them to work in too... it'd take some time for me to get used to them. Hurts my toe crack. My mom calls them "tongs" .... silent 'h'... idk why... chinelo is what they call them in Brazil.

Edited December 21, 2018 by Outbehindthebarn

[JoeH]

They would stop me from being able to do 50% of my work lol. Half the day I'm driving, other half I'm mixing and wheelbarrowing/raking concrete. When I'm not doing that I'm welding or an a roof. Boots every day, sun up to sun down.

[mrsmackpaul]

Yeah occasionally, depending on whats going on in Australia 

 

Paul

[Joe W.]

Quote

Question for you Paul:   Is the John Victor Ehret mentioned in the story above, the same Jack Ehret who was renowned for racing Vincent motorbikes, who died 2001? And did he get an A.O. medal?

 

[mrsmackpaul]

Joe I couldnt answer either of those questions 

I could try and find out if you like, it might take a while

 

Paul

[Adkat]

Great story Paul, reckon it's worth doing the rounds again 👍

 

[mrsmackpaul]

Quite right Adkat

As they say a picture is worth a thousand words 

John McLean photo

Jack Ehret Loadmaster! Taken at our truckstop in Gilgandra. This time Jack decided he'd leave the dog behind! I think this trip was to the Gunpowder mine.

 

 

Sime dribble from me now, this I believe is Fruehauf "Super Hefty"

A Super Hefty had chassis rails 450 mm or 18 inch deep, 100 mm x 25 mm or 4 inch x 1 inch top and bottom flange

Probably tared around 10 ton, I have a double rail McGrath trailer that is built along the same lines or principles, it tares at around 9.5 ton but isn't as strong as a Super Hefty Fruehauf, I can take the camber out once in a while with big weights on

On my Fruehauf Cattle Cruiser I have noticed a extreme amount of camber in the axles 

Super Hefty's had this as well 

Fruehauf rated the Super Hefty for 50 ton carrying capacity from the factory and plenty of blokes went past that suggested limit

Was some tough old blokes back then and even tougher trucks

 

Paul

[Swishy]

eye'm sure eye posted this n some time ago

 

cya

[Mark T]

7 hours ago, Swishy said:

eye'm sure eye posted this n some time ago

 

cya

Swish ????   I don't know if you posted this before or not, but for those of us who missed it..... we need a little story on this one.  "MACKWORTH"   ???

please do tell ????

[Swishy]

Hope n MRS jump in

& fill the gaps

or any body

cya

EDIT

Here U go

try page 4 of our local truck 4m

https://www.hcvc.com.au/forum/OldTruck/9069-jack-errit-and-his-jackbilts?start=0

Edited July 18, 2022 by Swishy

[mrsmackpaul]

Not much to fill in Swishman, all this stuff makes for interesting reading 

Shame the HCVC forum has had a few photo hiccups aling the way, a lot of good info gets lost

Lucky for the rest of world theres fruit loops like me and Swishman that saved some of these photos along the way or a lot of this stuff would be lost

Only problem is I saved stuff for years but never kept enough details of whos what when and were, people get it a bit cheesed of if people share their stuff without giving credit

Now in my defence I always say who it belongs to or who I think it belongs to and ask to be corrected 

Apparently (no apparently at all) some cheeky buggers share photos and claim them as there's and this really gets people cheesed off

 

Anyhow the SAR with E9 at 500 draft horses would of been a ball breaker

For those that dont know what a SAR Kenworth is 

It is short for "Short (as in bbc) Australian Right Hand Drive" 

Still a W 900 on the books but has SAR in it as well

 

Funny how Yanks all wanna sit low to the ground and out here we wanna sit up high so we can see what were about to hit before we hit it

Over to you Swishman to educate them more, I have about exhausted my KW knowledge lol

 

Paul

[mrsmackpaul]

Some more to this story courtesy of LLib Enilom

Is not my story at all

Here is a truck built by Jack Ehret. The first picture is of it loaded with 27 tons of pineboard from Oberon to Townsville. The second photo is bulk wheat stuck on Mount Tomah due to lack of traction, it had a 50/50 pusher under it. The third photo is the poor old worn out 6.71 getting a new set of bearings at Cassilis after the oil pump failed. The last photo was taken just north of Lotus Creek, with 27 tons of Otis lifts and escalators for the new Woolworths store in Townsville.

Some were in the Pilliga Scrub 

 

 

Rolling in a set of bearings near Cassilis

 

Beer o'clock just north of Lotus creek 1967

 

Paul

 

 

[cruiseliner64]

Super story of the Jackbilt...we will never see the likes of it again.Just regular guys getting it done.Of course the PC gang wouldnt allow it now.Oh the perfect time to have lived...

Paul

[mowerman]

Don’t know man society in general is all different now ,,,really a lot of talent went away with time…  I did change the water pump on an R model on a offramp that was 40 years ago. I was surprised I had everything I needed with me back then I really didn’t carry a whole lot of tools except for a small box. Bob

[Swishy]

Here sa nother big beautiful beast

 

Tri Drive 12V92T

Evan sez:

Never knew he converted it to tri-drive. From memory it's de-tuned to 700hp; twin turbo 12V92 Detroit. Originally an '80 or '81 TNT W-Model with a big ass amount of work on the bonnet extending the sides up 8 or so inches and raising the cab up on custom battery boxes. Hell of a nice truck and suprisingly quiet!

 

cya

 

 

[mechohaulic]

On 3/7/2025 at 10:53 PM, mowerman said:

Don’t know man society in general is all different now ,,,really a lot of talent went away with time…  I did change the water pump on an R model on a offramp that was 40 years ago. I was surprised I had everything I needed with me back then I really didn’t carry a whole lot of tools except for a small box. Bob

without a doubt different  today's world. main reason : liability; also lack of knowledge . yrs ago -after full day of work, did road call from CT to Maryland to change alternator on company COE. then there was a road call to upstate NY to change a steering box on K-123 COE during ice storm after a 8 hr work day. stayed in motel that early morning, today's world seems to say _ tow it in , were not chancing road calls.