tachometer question

[kenmac]

My original tach. on my 3110 went bad.My dealer sent me a new tach. that is different than the old original. The old tach. listed engine rpm and the same time pto rpm. as you can see in the picture the new tach. don't show what pto rpm is. There are 2 markings on this new tach. 1 st. mark at approx 22.50 rpm that says pto rated. The 2nd. mark at approx.25.25 (I guess you would call it) says pto max. My question is.Where should I run my rotary cutter pto rated or pto max?

 

[Jagmandave]

Can't really tell the markings from the pic, but why wouldn't you run the PTO at the same RPM you did before?

 

[kenmac]

As the old tach kept breaking tach cables , I don't know if it was ever correct.I know that the picture is not that good ,but it is the best of 4, thats why I listed where the marks are located .

 

[Normmm]

In the operators manual for your tractor is a chart of engin rpm/pto rpm. For instance on my tractor engin rpm of 2200 will give pto of 540 with pto in first gear. The other 3 pto gear ranges are also given. Also with pto in 2th gear an rpm of 1700 will also give 540 pto rpm. from my manual 1100(pto)/2300(engine) = 540/?, can be worked out for any pto gear range.

 

[kenmac]

The operators manual that I have for my tractor is for 336D.In my manual it is close to what you say 2258 for 540 pto rpm & 2294 for 1000 rpm in 1 st pto gear. As you can see on the new replacment tach it shows pto rated in the middle between 2000 & 2500 .I don't know if pto rated mark is 540 or more than 540 .Just looking at it ,the mark appears to be more than 2250.Where it says pto max just above the 2500 mark ( mabe 2550) Is this 1000 rpm?M y manual don't list 2,3,4, pto speeds My old tach showed those speeds ,but this new one don't. /forums/images/graemlins/confused.gif

 

[Soundguy]

Can you simply mark them over on the new face with an acrylic pencil? If they are both linear tachs.. simply look for the same 'location' on each tach.. etc.

soundguy

 

[kenmac]

Maybe an idea , although the old tach also reads pto rpmas well as engine rpm at the same time no matter what pto gear you are in. I called a company about repairing the tach. WOW! $185.00. Looks like I'm stuck with the new tach. /forums/images/graemlins/smirk.gif

 

[Tractors4u]

Ken,

Did the old tach have a double ended needle so that one end pointed at the engine RPMs and the other end pointed at the PTO RPMs? If so, do you still have the old tach? If you answered yes to these 2 questions, can't you just look at the old tach and get the appropriate RPMs and either mark it on the lens of the new tach or make a cheat sheet to put on the tractor?

 

[kenmac]

Brent, yes it does have dual needle on the tach& I can get some idea of where 540 should be. I have to decide if I will keep brand new tach & send old back to Tom.I think they did all they could do to locate me a tach b-4 sending me this new tach. I'm sure it wasn't cheap. ( warranty part for me) thanks for all the replies guys.

 

[Jagmandave]

If you know anyone who has one, a handheld tach attached to the PTO output will tell you what engine RPM equals what PTO rpm.

They look like this.....