davelakeside1 Posted August 1, 2022 Share Posted August 1, 2022 Looking for a 1990 Mack RW713 Tach. I found that the original Tach was a 17MT4103M6 which was superseded to a 83-161454. Mack has none in the US so if anyone has one that they would part with or know where I can get a new or a used one that would be greatly appreciated! Thanks! Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/ Share on other sites More sharing options...
Joey Mack Posted August 2, 2022 Share Posted August 2, 2022 (edited) wouldnt the RD/DM/RB/ .. be the same tach? I assume electric tach in this case? If so then there should be plenty of donor trucks to pick from.. jojjo Edited August 2, 2022 by Joey Mack wrong info Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505100 Share on other sites More sharing options...
Markie Man Posted August 2, 2022 Share Posted August 2, 2022 I assume your original is not working? If so Powl's Speedometer in Lancaster PA can restore it. They can fix electric and cable tachs and speedos like new. At our shop we do a fair bit of business with them. Now if yours is missing thats a different story. Glendon 2 Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505101 Share on other sites More sharing options...
davelakeside1 Posted August 2, 2022 Author Share Posted August 2, 2022 Thanks for the replies. Not that it makes any difference but I should have added that the truck has the E9 engine, the tach is a mechanical tach, and it has stopped working. If it was an electric tach getting a new one would not be a problem. It's coming out tomorrow or the next day to make absolutely certain that it is the tach and not the drive cable or the right angle drive on the engine. I replaced the cable and the drive a few years ago so that "should" be ok. The tach was working one minute and when I looked down a few minutes later it wasn't. Man, when you're so used to shifting with a tach, a speedometer, and the seat of your pants it's difficult to do without one of them! So it will be off to Powl's Speedometer in Lancaster PA to get rebuilt. Thank you, this site and all the guy's on it are fantastic! Thanks again for all your help! 2 Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505104 Share on other sites More sharing options...
Joey Mack Posted August 2, 2022 Share Posted August 2, 2022 (edited) can you unhook it and put a drill on it and spin it to see if the tach head works? you will need to be sure the cable is pushed all the way into the sheath, so you may only have a nub to chuck in the drill.. jojo Edited August 2, 2022 by Joey Mack wrong info 2 Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505151 Share on other sites More sharing options...
terry Posted August 2, 2022 Share Posted August 2, 2022 4 hours ago, Joey Mack said: can you unhook it at the injection pump and put a drill on it and spin it to see if the tach head works? you will need to be sure the cable is pushed all the way into the sheath, so you may only have a nub to chuck in the drill.. jojo What pumps have the tach drive on them, i thought all the earlier mack engine tachs were driven off the acc. drive shaft? terry 1 Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505169 Share on other sites More sharing options...
Joey Mack Posted August 2, 2022 Share Posted August 2, 2022 (edited) I thought I was wrong on that, and yesterday I just worked on an E-9 Superliner and didnt open the hood to look.. I guess I was thinking about location.. Shame on me.. Your right Terry... I shouldnt have posted.. jojo Edited August 2, 2022 by Joey Mack wrong info 1 Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505170 Share on other sites More sharing options...
Joey Mack Posted August 3, 2022 Share Posted August 3, 2022 Im just curiuos?? does it really make a difference if it's an E-9 instead a 6 cylinder, since it is gear driven and not counting electric pulses from a distributer in a gas engine? I ask because I would expect this to be easy to replace.. jojo Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505216 Share on other sites More sharing options...
AZB755V8 Posted August 3, 2022 Share Posted August 3, 2022 3 hours ago, Joey Mack said: Im just curiuos?? does it really make a difference if it's an E-9 instead a 6 cylinder, since it is gear driven and not counting electric pulses from a distributer in a gas engine? I ask because I would expect this to be easy to replace.. jojo A mechanical tach can be used on any size engine or cylinder count. They all rotate at a standard RPM rate so any tach will read the same. On an E9 the V-pump is mechanical with the tach drive on the front of the auxiliary drive housing inline with the injector pump. The inline pumps are electronic tach's with the pickup on the flywheel. A solution is adding a sensor and pickup on the harmonic balancer and go with a new electronic tach. Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-505235 Share on other sites More sharing options...
davelakeside1 Posted August 24, 2022 Author Share Posted August 24, 2022 Sorry for not replying back on the Tach issue. The tach got put on the back burner for a while. The old 9 speed decided decided to swallow a shift fork and unfortunately chipped up a few gear teeth before landing in the bottom of the trans. I wound up going for a 10 speed and almost done with that. Turned out that there were 12 other parts that needed to be replaced including the trans oil pump. Didn't see that one coming! The extra added attraction was I ordered a new stick shift. That one hit the dash so I can't get at the top gears. The one I need has been obsoleted for the old Superliners. The hits just keep on coming! As soon as I get a breather, I'll figure out if it's the tach, the cable, or the right angle tach drive. Thanks for all your help! Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-507342 Share on other sites More sharing options...
Joey Mack Posted August 24, 2022 Share Posted August 24, 2022 Good luck, Glad you got back in touch. jojo Quote Link to comment https://www.bigmacktrucks.com/topic/70212-rw713-tach/#findComment-507360 Share on other sites More sharing options...
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