RL600 Concrete mixer question

[Whiskymack]

I'm planning to build a scale model of the above based on the one that appears in Beverly Hills Cop 2. I'm  using an AMT Kenworth Challenge mixer kit  but building my own RL600 frame  It has a front mounted hydraulic pump/tank and oil cooler but there is no mechanical drive to the pump included in the kit. The pump sits behind the front bumper extension not connected to anything! I have been told that there should be a drive shaft coming from the back of it which passes either under or through the radiator and connects with the large flywheel pulley on the front of the crankshaft. I have a couple of internet pics of a similar RL685 mixer but I just cannot see what's what. Can anyone explain how a front mounted hydraulic pump would be driven on an RS/RL model? Any pictures would be great.

Many Thanks.

[mowerman]

Sorry I can’t help but I do remember transit mixed in Southern California had tons of those they were real nice looking rigs they were red with white barrels. I don’t know what happened to the company I left the area and 94 and a returned 5 years ago and they were gone.. bob

[Freightrain]

Interesting project.  I'm curious now if those were direct drive, full time pumps(likely).

[RoadwayR]

That mixer in the movie was a old Livingston-Graham unit, they had a lot of R model mixers.  Bonanza and Conrock had them too.  You are correct about the pump drive, there should be a shaft coming off the engine crank pully passing under the radiator driving the pump.  The front frame crossmember had a U-shaped hole for the shaft to go through.    

[mrsmackpaul]

The shaft would be under the radiator as the crank is bellow the radiator

And it's  told to "blue tooth" it across, blue tooth wasn't even invented then 🤔

 

Paul 

 

 

[Whiskymack]

Thank you for all the suggestions. I think I have found the answer. It looks like there is a square opening in the bottom of the radiator core for the shaft to pass through. The Radiators on RS/RL models are tall and drop down below the level of the crankshaft so I guess  the opening was the only way it would work.

[JoeH]

I have a DM686sx that was a barrel truck. 1980. Has a monster bumper, I'll try and get a picture of the radiator/pump bracket.

[JoeH]

[JoeH]

I have a 2003 MR688S also that had a pump on the front.  It has the tall radiator like you mentioned with a hole through the middle. let me know if you want pictures, but it is a different model altogether.

[JoeH]

The pump is live, always on.  On trash trucks, the pump has a protection circuit.  If the hydraulic system loses oil, a butterfly valve closes and oil is circulated through a metal pipe from the pressure side of the pump to the suction side.  This way you can limp the truck along without destroying a $3,000 (guessing) pump.