skydawg Posted January 6, 2023 Share Posted January 6, 2023 I have two"PULL TO STOP ENGINE" dash knobs.The one next to the ash tray does stop the engine,I think by shutting off fuel to the injection pump.The other knob,to the left of the steering wheel doesn`t have any effect.Is this one supposed to cut off air somehow? Thanks. Quote Link to comment Share on other sites More sharing options...
h67st Posted January 6, 2023 Share Posted January 6, 2023 My truck had a valve on the inlet side of the fuel pump that had a cable hooked to it, maybe your truck had the same thing. The valve could be an emergency shutoff in case the regular shutoff doesn't work. Quote Link to comment Share on other sites More sharing options...
mechohaulic Posted January 6, 2023 Share Posted January 6, 2023 did you trace the cable to find where the other end is connected? possibly someone used an eng shut off cable for some other function ?? 2 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted January 6, 2023 Share Posted January 6, 2023 Wasnt the left side pull knob the secondary throttle cable? It was a 'T' handle, and some times replaced with a knob that twists and locks. Trace the cable to see where it goes.. I bet it goes to the back of the injection pump, opposite the foot throttle linkage.. it may also go to a lever on the firewall bellcrank, if you have rods for the throttle linkage instead of a cable.. 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted January 6, 2023 Share Posted January 6, 2023 I just realized its a 'B' model.. I was thinking 'R' model.. I dont know much about 'B' models... Ooops.. jojo 1 Quote Link to comment Share on other sites More sharing options...
terry Posted January 7, 2023 Share Posted January 7, 2023 1 hour ago, Joey Mack said: I just realized its a 'B' model.. I was thinking 'R' model.. I dont know much about 'B' models... Ooops.. jojo Yeah it’s supposed to be a throttle cable. Terry 1 Quote Link to comment Share on other sites More sharing options...
mowerman Posted January 7, 2023 Share Posted January 7, 2023 Yes, that’s what I was thinking throttle cable to pump up the RPMs, another lost art ha ha… Bob Quote Link to comment Share on other sites More sharing options...
skydawg Posted January 7, 2023 Author Share Posted January 7, 2023 I have a throttle knob...it works but won`t stay pulled out,I have to hold it in position as the engine warms up. I`ll trace the inoperative PULL TO STOP ENGINE knob cable,if there is one. Quote Link to comment Share on other sites More sharing options...
Freightrain Posted January 7, 2023 Share Posted January 7, 2023 Sounds like someone jeery rigged something on that left side one. The hand throttle is always twist to lock. If not, it won't hold well. Might be worn out? Damaged? 1 1 Quote Larry 1959 B61 Liv'n Large...................... Charter member of the "MACK PACK" Link to comment Share on other sites More sharing options...
mechohaulic Posted January 7, 2023 Share Posted January 7, 2023 handle on the engine stop a straight solid shank;; hand throttle shaft is a "splined" tooth so it can be twisted and locked into desired rpm setting. both knobs should have been on right side of dash one above the other.oops that's R model !! a cable control on left side ??? most controls were air or manual operate( front wheel limiter etc) . doesn't seem someone would go the time to run a spare cable assy (eng stop) for a non functioning throttle. Quote Link to comment Share on other sites More sharing options...
mechohaulic Posted January 7, 2023 Share Posted January 7, 2023 racking the brain cells, there were back in the day units (Mack) with emergency shut offs ( besides DD). the cable ran to a brass valve threaded in to the injection pump between fuel inlet line and pump. like the hand primer pump , cost cutting / better Technolgy eliminated the emergency shut off. wager a bet following the left cable it comes out to the injection pump. the shut off valve removed with brass fitting installed or valve there with broken cable. 1 Quote Link to comment Share on other sites More sharing options...
mowerman Posted January 7, 2023 Share Posted January 7, 2023 Maybe it used to be a gas job and it is a choke cable… Bob Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted January 7, 2023 Share Posted January 7, 2023 I remember that cable and valve on some old macks.It shut the fuel supply off instead of moving the rack to a no fuel position.For a hung or frozen rack it may be hard to shut the engine down. 1 Quote glenn akers Link to comment Share on other sites More sharing options...
skydawg Posted January 7, 2023 Author Share Posted January 7, 2023 Mechohaulic,you`re right...the cable moves a lever at a brass fitting on the IP,but doesn`t shut off fuel.The internals must be broken or removed?The other shutoff cable moves a lever just ahead of the governor at the rear of the pump. 1 1 Quote Link to comment Share on other sites More sharing options...
mechohaulic Posted January 8, 2023 Share Posted January 8, 2023 thank you for update Quote Link to comment Share on other sites More sharing options...
mechohaulic Posted January 8, 2023 Share Posted January 8, 2023 22 hours ago, skydawg said: Mechohaulic,you`re right...the cable moves a lever at a brass fitting on the IP,but doesn`t shut off fuel.The internals must be broken or removed?The other shutoff cable moves a lever just ahead of the governor at the rear of the pump. there is a possibility the emergency stop cable (left side ) is broke internally. move handle in cab then check position of other end at fuel inlet line to see if the lever changes position. if the cable is broke . definitely want to make sure the valve isn't partially restricting fuel to engine. would be a simple overlooked item if unit has loss of power. 2 Quote Link to comment Share on other sites More sharing options...
mechohaulic Posted January 8, 2023 Share Posted January 8, 2023 On 1/7/2023 at 10:56 AM, mowerman said: Maybe it used to be a gas job and it is a choke cable… Bob anything is /was possible. 1= a 613 (odd number) diesel;;2- gas engine shouldn't require an engine / emergency shut down . just sayin. I like this forum sure helps keep the brain cell functioning. the brass shut off valve made real good air tank fill valves also. same 1/4 pipe thread. not sayin I took the emergency shut off valves from ole trade ins ; they just "showed up " in my toolbox 😁 Quote Link to comment Share on other sites More sharing options...
mowerman Posted January 8, 2023 Share Posted January 8, 2023 Ha ha I just buy all that stuff at Home Depot but free bees are always welcome I am the type that walks along. It picks up all the bolts and nuts and washers. I find on the ground and stick them in my pocket. Quote Link to comment Share on other sites More sharing options...
skydawg Posted January 9, 2023 Author Share Posted January 9, 2023 The lever at the pump moves and rotates it`s shaft when I pull the dash knob,just doesn`t stop the engine.I could open the fitting,but it`s not leaking....and it`s cold out. Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted January 9, 2023 Share Posted January 9, 2023 If you asking for help i would say remove the cable from the lever and then move the lever all the way and see if it kills engine.If it does the you can readjust the cable. 1 Quote glenn akers Link to comment Share on other sites More sharing options...
skydawg Posted January 9, 2023 Author Share Posted January 9, 2023 Ok,I`ll see if the lever isn`t moving it`s full travel.If that valve did close on shutdown,would it help to keep the fuel system primed?I don`t have a manual primer on the supply pump. Quote Link to comment Share on other sites More sharing options...
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