Newbie needs some info on old mack B-61's

[Superdog]

Those are Tachographs,Black boxes of the 50's to 80's,they were used to record driving time,speed,RPMs,etc.They had little paper discs in them to record info on,company had the key to prevent driver tampering,but resourceful old timers had ways of "fixing" them.

[vision386]

For you commercial drivers. What are the boxes between the steering wheel in one of the first pictures. Quite a find.

Those are Tachographs,used to record speed,idle time,MPG etc. kind of a prehistoric "black box".................................Mark

[David]

Great minds think alike (and at the same time). Why would there be two in one truck?

[vision386]

I'm not sure what the boxes are and didn't get a good look to be honest. They both have keyed locks in them I remember and you can see the key sticking out of one of them. That is the sleeper cab truck also. Any info anyone? I will take better pics tomorrow.

Those are Tachographs used to record speed,idle time,MPG, etc. kind of a "black box" the reason there are two makes sense now that i know its in the sleeper tractor,prolly driven by a team at some point,each driver had his own,they use a small paper disc to record each drivers activity daily,and are also a clock,the key being with it is rare,as the drivers would not normally have access to prevent tampering with it................................Mark

[vision386]

Great minds think alike (and at the same time). Why would there be two in one truck?

Sure seems thataway! LOL!..................................see last post! Mark

[Bowfisher35]

great information, pretty interesting and enjoyable learning new things I have no clue about lol i have another question what would be the approx. curb weight of the tandem tractor and the single axle tractor. Need to make sure I have enough equipment and big enough trailer when it freezes enough to move them.

[jaysm35a2]

You can pick em up on Ebay and they arent very expencive. Thats cool that Mark noticed the two were for team drivers.

Not sure on a tandem but a S/A B61 like that should weigh in around 11k lbs empty. Mine did on the scales.

[Bowfisher35]

that's a little heavier than I expected. I had no clue really but was guessing around 9,000 on the single axles so that's good to know. They been sitting a good while but the last time they was moved about 5 yrs ago supposedly they rolled freely but it's very soggy where there at and they've settled in some. Might take me a dozer to get them out lol

[Superdog]

That tandem is most likely a tag axle guessing by age,probably weigh around 14,000,not over 15,000,since it's missing some stuff.

[other dog]

Those are Tachographs,Black boxes of the 50's to 80's,they were used to record driving time,speed,RPMs,etc.They had little paper discs in them to record info on,company had the key to prevent driver tampering,but resourceful old timers had ways of "fixing" them.

A friend of mine drove for Overnite and when they still used tachographs he told me they could stick something in them somewhere so the needle couldn't go past 55 mph, but it wouldn't let the needle "bounce" and the line was too smooth, so they came up with something else that let the needle move just a little bit so it wouldn't look like it had been tampered with.

And yeah, that's a real fine find there!

[daveigou]

Great minds think alike (and at the same time). Why would there be two in one truck?

One probably recorded MPH, & time, the other was likely RPM's, so the owner could see if he was over-revving the engine, so as to make sure he was throwing it in nuetral down those long hills instead of overspeeding the engine. (DO NOT try that at home!! I'm sure none of us here on BMT ever did such a thing)

[other dog]

One probably recorded MPH, & time, the other was likely RPM's, so the owner could see if he was over-revving the engine, so as to make sure he was throwing it in nuetral down those long hills instead of overspeeding the engine. (DO NOT try that at home!! I'm sure none of us here on BMT ever did such a thing)

I never did , but I remember the first truck I drove with a jake brake. Started down the long hill on 460 between Christiansburg and Blacksburg one night, got up to max speed, put it in neutral, let the clutch out, and the engine cut off . That was when the jake didn't automatically cut off below a certain rpm, it would still work at idle. It was straight down the hill and up the other side.

[fauthpk]

Thanks for the info about the black boxes. Regarding the jake I have heard stories, and it may be stories that if they ran the jake too long past idle the engine would run in reverse. Not sure that is even possible!

My little B20 weighs 9100lbs. So the guess of 11k is probably pretty close, hence, built like a Mack truck!

[Bowfisher35]

Thanks again for all the info guys. I went today and took alot more pics and will get them up tonight for everyone to look at. Like I said it's very muddy here and gonna take a little time to get em out to where there accessible but we'd be open to offers on one or all once we get them moved.

[jaysm35a2]

Wasnt a guess of 11k lbs , it was on a scale. I wanted to make sure everything was in order for the drive home to NC from PA. A B61 will weigh alot more than a B20. Thats pretty cool that they dont weigh much , maybe il need one. Then I wont have to worry about all the street signs saying no trucks over 10k.

My U609 weighs in right at what a B61 does according to the spec sheet, I havent taken that one on a scale yet.

[Bobby Covert]

Been a b-model fan for years never saw a sleeper like that. The window seems to match the Mack sleeper windows in previous and current Macks for that time. Look for the serial number under the passenger side fender well, on the frame. Probably will need a rag and some cleaner to see it.

[Bowfisher35]

ok thanks i'll check that out I got pics of the tag on the passenger side door but not much info on that only that it's a B-61ST and a 4 digit number after that i'm uploading pictures to photobucket now will be a few minutes also the tandem is not a tag axle it has 2 live axles. pics in a few minutes

[Bowfisher35]

ok here they are very rusty and crusty but maybe useable for someone. Most floors are gone. the green truck is a B-61T and the frame has been cut off on the back on one side and the black/green truck has a door tag but the door is shot and wouldn't open and the frame has been cut off on it as well. http://photobucket.com/bowfisher35

[umodelnut]

wow cool photos! i really do like that one with the sleeper.

[Bowfisher35]

pics didnt turn out as good as i hoped some are to close up to tell what is going on. My camera took a crap and i was using my girlfriends "good" camera lol

[hatcity]

Pics of girlfriend then.

[fxfymn]

may be stories that if they ran the jake too long past idle the engine would run in reverse. Not sure that is even possible!

Don't know about the Jake brake causing it, but I can definetly attest that you can get a diesel to run backwards. Just stall it out on a hill and let it roll back with the clutch out. Makes enough smoke to kill every mosquito in a five square mile area. And yes I did it several times while trying to master an ALF tiller truck with an 6-71 Detroit.

[Bowfisher35]

I see some of you all talking about this mack museum? Would they be able to tell me anything about this sleeper truck? If so what all do I need to do and does it cost anything?

[Maddog13407]

that sleeper cab b61st is awesome. definately a very early ones. never seen a b model with an aluminum trunnion like that one and you can tell its a 53-56 cause it has the raised crossmember for the rear suspension. definately worth saving but not worth $5000. remember most of us are working stiffs and just wanna have and save as many of these beauties as possible haha.

[fauthpk]

If you give the Mack museum the vin they will send you all the info they have on it. You can try to call the Mack curator Don and see if he can tell you anything over the phone or with emailed pictures. Nice find. It is neat to see some unusual b models.