mackkid

Just playing that's all. I reckon if you got 2 sticks you may as well be able to play with both of them

Hello Guys

I have a 237 6 speed i'm thinking about putting a trq7220 into how much difference is in the bell housings will the one from the six fit ? input shaft length etc. The box I'm looking at doesn't have a housing or sticks

Thanks Steve Australia

Bill

The puff limiter basically stops the rack in the pump from opening up fully until the engine can handle the fuel. The valve in the pic is as you suspected the control valve operated by vacuum. You should have air to the limiter valve which is on the front of the fuel pump at idle with the maxi brakes off. This stops the rack fully opening untill the revs are up enough to take the fuel. the other line is hooked up to reverse to stop the rack opening fully when in reverse. My guess is the control valve is gummed up if you don't get air out of the port going to the pump. you can pull it apart to clean out. Black smoke is unburnt fuel and too much can wash the oil off the bore and lead to cylinder wear.

Hope I have been some help

Steve.

Hi All

Anyone know where I can get a maxidyne badge.

I have 1 but would like another

what models were they on?

I also need the shift pattern decal for a 2 stick 6 speed

Thanks Steve

Man i'd love that but i'm in Australia

Always the way

Steve

Name: MACK R 685 RST (1975)

Date Added: 21 June 2008 - 11:39 AM

Owner: mackkid

Short Description: 237 6speed on 34s

View Vehicle

my 80 mack with a 237 has a wiered idle problem. start it up and idles fine after 5 minutes or so it will jump up about 200 rpm's and idle to high. if i wack the throtle it will come back down and then it will eventually high idle again. injection pump was done 2 years ago. any thoughts?

I Be guessing problem with governer

Hi All

In the old store there were Maxidyne badges listed are these still available?

Steve

Hello to whoever you are

Why don't guys end a post with their name ?? What don't you have one?

Beat's me but I think this makes for a more personal group

Anyway Here's how

Firing order

153 624

First off get no 1 on tdc compression stroke this can be seen when no 6 is rocking (ex just closing inlet about to open ) set no 1

Rotate engine till no 2 in rocking set no 5 then when 4 is rocking set no 3 then 1 rocking set 6 and so on see how it goes

Divide the fireing order in half work on one set the other

this can be done with any engine

Divide the firing order in half and like I said get one rocking and set the corresponding cylinder

Oh and if it has dynatard on it be sure to push down on the tappet to close the oil gap on the exhaust Hope this helps

Steve

Sounds Great Can't wait for that R model store!!!

Steve

Rob have a look in my gallery.

steering wheel is on the other side to yours but might help

Steve

Actually, the 10 & 12 speed transmissions would not have been factory options on a R685ST.

.

Maybe not in a r685ST but were available in a R685 RST

Steve

Well, I never knew. You know me, always willing to help a guy out.

Enjoy.

Rob

over here we need a permit and signage to move any thing slightly over width Don't see any signs on that Altho plenty room to attach one

My 75 CF-600 has the factory engine brake I have always called them jake brakes but I know that mack calles them something else. How is it supposed to work mine dosen't feel like it does anything. I know that the switch has to be in the dry road position but that is all I know. Can anyone tell me how this system is suppose to work.

That would be the Mack Dynatard.The engine model number will have a B in it eg.675entb on the plate behind the fuel pump on the block.

The jacobs brake system is entirely different being a bolt on system. These are easy to pick as they use a spacer between the block and rocker cover. Altho some early Macks were fitted with jacobs brakes Mack developed their own system calling it the Dynatard..

With any engine brake the engine is basicly turned into a compressor

Without going on for hours this is my understanding.

The Dynatard uses a special profile on the cam lobe of the exhaust valves

When the system is engaged basicly oil is pumped into a piston in the rocker thus giving zero clearance between the rocker and valve. This opens the exhaust valve just before top dead centre on the compression stroke. This already compressed air flowing thru the manifold and turbo increases charging pressure into the engine. This increased flow gives the retardation.

You should be able to hear it if it's working! Check you have power to the solenoids (on top of the rocker cover) when the system is switched on.

Hope this helps a little

Steve

Hi Adrian

R is the model

6 denotes the GVM 20884 to 27240 kg

85 in your case is the endt/b 675 237 hp maxidyne

in later models it was the em6

The 686 were the cool power engines

R Right hand drive

St is bogie drive light weight thus your 34ooolbs rears

What ratio are they 4.17s maybe?

The 34000 lb bogie also came out with aluminium carriers as a lighter tare option

Transmissions were 5 speed with the two stick 6 speed 10 and 12 speed air shift as options

steve

It's unbelievable that someone can treat a vehicle that is paying their bills so bad. If the inside looks this bad, I can only imagine just how good he serviced the truck. It was almost painful to drag all the trash out of this truck!

Believe it or not - I used my pressure cleaner right in the cab to get the grim out!

Great job! It always gives great satisfaction to do something and then look 100% better than when you started. I take it the rag between the turn signal switch and steering wheel wasn't there to wipe off the dash!

steve

Well the owner of the truck lot will not sell me that truck. He said he made a deal with the company he bought it off of not to sell it to anyone in the area. Them septic guys around my area are roughneck SOBs. I know i was one. O well i will just have to keep my eyes open.

Sounds like them septic guys stirring some Shi#

Those 4 spring suspensions are fine till you get off bitumen and then the first thing you'll wearout is the cross lock switch lol

Steve

Hi Basil

I'm thinking these Macks were built for Goldsworthy Mining from Perth in '73

They were 375hp thermodynes (ENDT866) with 12 sp maxitorque air shift transmissions and mack 80,000 lb bogies on 14.00 24 tyres.

They were designated A8 R897RSX

They pulled gaint tippers for their time 31 feet long and 10ft6 wide The tipper sides were 1/2inch plate and 3/4 inch for the floor GVM was 104 tons

Yes R Models on Steroids

Steve

Hi All

I've just added two new pic's to my gallery, one when I first got the truck in Nov last year and at the Allora heritage show in Jan this year. I have just received some spec's from Mack (oops Volvo) in Brisbane Australia on my truck and am delighted to find all serial numbers ( Engine Trans and Diffs )all are original.

May I also take this opportunity to wish each and everyone and their families a Safe and Happy Christmas and New Year

Take Care

Regards Steve

Hi Milo

Welcome to the group. I think the mirrors were an option from 74 as I have a photo from the '74 Brisbane truck show in a bulldog bulletin showing a R686 with the square mirrors with the dogs. Then a new truck in a '75 bulletin with the bubble ones but with bullet type cab lights. So I think you must have been able to order a R model with different mirrors and cab lights. The cab was lengthened by 3 inches in late '75 as my r685 has the short cab and plated 6/75 It has the square mirrors and bullet lights but I can't be sure these were fitted on the truck from factory. Where on the downs are you? I'm in Toowoomba

Steve

Monty, Chuck (kingsofsalvage) in the U,S has a set of black mirrors on ebay at the moment $61 U.S

I got a set from him $55 u.s to post to OZ check them out he's great to deal with

Steve

HI spotted this pair on ebay today http://cgi.ebay.com/ebaymotors/ws/eBayISAP...sid=p2759.l1259

and was wondering if the dude is asking to much?. am getting a bit edgy as i want to gett the last few bits for my rig.

Mirrors and a sun visors are the two items that have become the most elusive and potentially the most expensive to track down. or may be i should just hold tight till the group order goes through hope fully.

thanks monty

Monty I bought a set of black ones off that guy good to deal with. $55 us to post to Aus

Cheers steve

how many of us aussies are on here?

let me know

Steve

Rod I've seen many different bends, extensions etc. on quad box sticks

In the workshop if you saw oxy hoses running into the cab you knew what was going on!

Because we sit on the opposite side to you guys the compound stick was usually extended with a Cat knob as the preferred method

Steve

Hi All

I,m looking for the 2.5 inch clear park lights next to the headlight on an R600

The original ones were surface mount with removable lens and bulb. All I can find are sealed units that require a grommet to mount them which in turn needs a 3 inch hole to be drilled in the hood. This is something I don't realy want to do!

Any help would be great

Thanks Steve in Australia