B75 vs LTL

[Joseph Cummings]

19 hours ago, Mark T said:

That's a Small Cam of some form. PT270, 290 or 335 ?  Hard to tell much more ( at least for me )  no intercooler, so it's not a 350 or 400 Magnum

It looked like the tag was still on it. It could be whatever he wants with a 10 dollar button and 15 minutes work if he doesn't mind a little smoke

[mowerman]

Yeah, so was I that’s terrific price there’s a lot there for the money

[topo]

I remember seeing that Mack in Cortez Colorado in the 70s'and early 80's seating in front the diesel shop next to the truck stop cafe waiting to go to work . 

[mowerman]

seems that truck was just recently featured on here ,,,bob

[skydawg]

3 hours ago, Joseph Cummings said:

It looked like the tag was still on it. It could be whatever he wants with a 10 dollar button and 15 minutes work if he doesn't mind a little smoke

What does that mean?

[mechohaulic]

17 minutes ago, skydawg said:

What does that mean?

in  the real days of trucking and mechanics way before computers ruined everything ; engine such as cummins could be "modified" horsepower wise with the use of "buttons" as they were called. simple terms fancy flat washers of different thickness installed in the pumps.

[mechohaulic]

2 minutes ago, mechohaulic said:

in  the real days of trucking and mechanics way before computers ruined everything ; engine such as cummins could be "modified" horsepower wise with the use of "buttons" as they were called. simple terms fancy flat washers of different thickness installed in the pumps.

oh the good ole fun days;  besides a change of buttons. there was the "add a little gas" to the fuel tank to get "more horsepower from the diesel fuel. had to know what you were doing or results could be costly .LOL or the vise grips on the return fuel line . and a few more but we don't want to go off topic.

[reb87]

1 hour ago, topo said:

I remember seeing that Mack in Cortez Colorado in the 70s'and early 80's seating in front the diesel shop next to the truck stop cafe waiting to go to work . 

Awesome!

[Joseph Cummings]

3 hours ago, skydawg said:

What does that mean?

The top picture is the "Button" (Idle Spring Plunger) The lower the number, the more the funner 

The Shims are for the high speed spring to change the max RPM. 

The bottom picture is a cutaway of the PT pump, I drew a little red line on the button

There are other things to do if you really want to tailor the hp and torque / HP curve, but most times all that gets done is the button and the shims. Depending on what engine you start with, there is an easy 100-200 hp there if you want to go that far

[skydawg]

Ok,thanks.A lot going on w/ injection pumps.

[cruiseliner64]

14 hours ago, reb87 said:

It sold on “bring a trailer” for 11000 a year ago,that’s why there were videos on yt,  don’t know why it ended up at Richie.  Apparently the title wasn’t right so Richie pulled it and got a new vin/Colorado title for it for this sale.  I was surprised how low I got it for. 

Wow you got two beautiful bargains there.If I lived in the US there would have been a bidding war between us....best of luck with them.they are pure class..

Paul

[mowerman]

Yeah, Mecho when I heard him mention button, I thought to myself my God I haven’t heard that in years we also used to bump up the top end with a jump wire. I don’t remember what that was all about.

[mowerman]

We also used to be able to bypass the electrics and put them on manual. I don’t even remember how to do it. It’s been too long. Another words up your generator takes a shit and you have no charging the engine will just keep running and you can drive it anywhere you want With no electricity nowadays I don’t think you could do any of those things

[reb87]

42 minutes ago, mowerman said:

We also used to be able to bypass the electrics and put them on manual. I don’t even remember how to do it. It’s been too long. Another words up your generator takes a shit and you have no charging the engine will just keep running and you can drive it anywhere you want With no electricity nowadays I don’t think you could do any of those things

On my big cam 400hp Cummins and my nhc250 hp 855’s I can screw in a screw on the fuel shutoff solenoid and bypass the solenoid to run without voltage.  I don’t really want any modern computer controlled diesels

[mowerman]

lol well at my age and status i doubt i will ever own anything but the DM .bob

[mowerman]

i think the last one i put on manual,,,,,i had to wind something in on the fuel pump as you mentioned but it was attached to the side of the pump,,,i just had to turn it with my hand,,,,that was 35 years ago,,,alternator quit,,,i was able to drive it in,,,bob

[mechohaulic]

1 hour ago, mowerman said:

i think the last one i put on manual,,,,,i had to wind something in on the fuel pump as you mentioned but it was attached to the side of the pump,,,i just had to turn it with my hand,,,,that was 35 years ago,,,alternator quit,,,i was able to drive it in,,,bob

it will run with the knurled screw turned in; just won't shut off with key. had to either stall it or turn screw back out. number of road calls yrs back having the issue.

[Brocky]

2 minutes ago, mechohaulic said:

it will run with the knurled screw turned in; just won't shut off with key. had to either stall it or turn screw back out. number of road calls yrs back having the issue.

Thanks

I have done that several times over the years to get a truck back to the shop...

[cruiseliner64]

1 hour ago, mechohaulic said:

it will run with the knurled screw turned in; just won't shut off with key. had to either stall it or turn screw back out. number of road calls yrs back having the issue.

Same here.I remember one stormy night rescueing a GUY truck(British Layland)with a 220 cummins which the driver said just stopped.After confirming no power at the pump we screwed in the screw on the pump and got it back to the yard.Turned out the fuse for the wipers blew and that fuse also supplied the pump solenoid....

Paul

Edited December 6 by cruiseliner64

[Geoff Weeks]

My 3406B Cat has the solenoid removed, air start, cable shut down doesn't need power to start or run.

 Both Cummins had the fuel solenoid operational, but the power required is minimal. 

Still have a selection of "buttons" for Cummins pumps and at least one "rebuild kit".

 Easy to turn up a Cummins pump, but also easy to screw one up if you have no idea what you are doing. Or at least turn one up so it doesn't do damage long term.

[mowerman]

ya same here,,,my DM is the same way,,,dont even need a key,,,,and yes,you gotta be careful with buttons,,,you can burn holes in your pistons,,you can only go up so far,,,most times,if your truck doesnt handle what you need,,,better to trade it for a newer model...lol.easy for me to say,,bob

[Geoff Weeks]

3 hours ago, mowerman said:

ya same here,,,my DM is the same way,,,dont even need a key,,,,and yes,you gotta be careful with buttons,,,you can burn holes in your pistons,,you can only go up so far,,,most times,if your truck doesnt handle what you need,,,better to trade it for a newer model...lol.easy for me to say,,bob

On mine, I can put a shut off valve or solenoid on the line from the button or nose of the starter to the big relay valve on the tank, so it will not start without a key. A hidden shut-off in that line can be hidden, and doesn't have to be as air tight as the button as it only "sees" pressure when the button is depressed.

 My Cummins powered cab-overs used a gas rated solenoid and the original electric start button, the Cat powered Marmon got the air button and cable shut down.

[1961H67]

I had a good collection of those Buttons from where I worked at Ryder for 30 years, the drivers would have them installed on the road,, we had a portable pump stand we would hook up and check the fuel pressure, I would install a factory Button back, Yes anything in the single digits would Roll Coal ! I had a box with snap rings, plyers, stacks of shims and probably 20 “ Hot Buttons “ . They ALL got washed away in the flood in September.

[Geoff Weeks]

Last I knew you could still get them new from any Interstate Mcbee dealer. weren't expensive.

IIRC I never went below 17 or 15 depended on the size of the injector nozzle.

Too much pressure on a nozzle that can't spray enough volume can wipe the cam or break rocker, bend push-rod.

Without enough air you crack pistons and shake the liners loose.

A little brown out the pipe pulling hard is fine, "rolling coal" is just stupid and damaging.

 I haul OD loads and often was wide open all day, you wouldn't survive the trip if you were "rolling coal" the whole way.

[1961H67]

You are exactly right,,, But,,, you know how some of those “ Drivers “ are who don’t own the trucks,,, it would be a different story if they had to buy fuel or pay for a engine.