BookspanS Posted September 8, 2008 Share Posted September 8, 2008 Is it a direct swap from the guage with a spedometer and gas guage and all the dummy lights, to the guage with the tach and all the other guages? FYI Going from this: Can I plug even for this so all the guages work directly just swiching plugs from one to hte other? Link to comment Share on other sites More sharing options...
Eagle Posted September 8, 2008 Share Posted September 8, 2008 Yupp. Plug-n-Play Link to comment Share on other sites More sharing options...
deziped Posted September 8, 2008 Share Posted September 8, 2008 NOPE. Gotta change the oil pressure and temp sensor Link to comment Share on other sites More sharing options...
BookspanS Posted September 8, 2008 Author Share Posted September 8, 2008 Ok, now yall have me confused....but is there any extra wiring for the tach? or are those wired just hangin out behind it with nothing plugged into it? but yall have me confused about the oil pres. and the temp. how would i get that wired in? Link to comment Share on other sites More sharing options...
Pete M Posted September 8, 2008 Share Posted September 8, 2008 It's plug-and-play in the sense that you don't have to run any wiring. The Tach is pre-wired in. The oil pressure and temp sensor on the engine are just dumb"switches" for the lights and those switches will need to be swapped for "sensors" to get readings on their respective gauges. Link to comment Share on other sites More sharing options...
Boilermaker Posted September 8, 2008 Share Posted September 8, 2008 Not to kill a sale...but i had to double check. Your MJ is an '86, right? I don't think my '91 gauge cluster will work (someone correct me if i'm wrong). I'd feel pretty bad sending you something you couldn't use. Link to comment Share on other sites More sharing options...
Eagle Posted September 8, 2008 Share Posted September 8, 2008 NOPE. Gotta change the oil pressure and temp sensor No, because he already has gauges, not idiot lights. Read question before answering, Grasshopper. Boilermaker is correct -- 91 and newer uses an electronic speedo and the clusters do not interchange with the older models using mechanical speedos. Link to comment Share on other sites More sharing options...
maddzz1 Posted September 8, 2008 Share Posted September 8, 2008 NOPE. Gotta change the oil pressure and temp sensor No, because he already has gauges, not idiot lights. Read question before answering, Grasshopper. Boilermaker is correct -- 91 and newer uses an electronic speedo and the clusters do not interchange with the older models using mechanical speedos. In the original question and the pic he has idiot lights. Its a little confusing because he says gauge instead of cluster. Link to comment Share on other sites More sharing options...
Eagle Posted September 8, 2008 Share Posted September 8, 2008 NOPE. Gotta change the oil pressure and temp sensor No, because he already has gauges, not idiot lights. Read question before answering, Grasshopper. Boilermaker is correct -- 91 and newer uses an electronic speedo and the clusters do not interchange with the older models using mechanical speedos. In the original question and the pic he has idiot lights. Its a little confusing because he says gauge instead of cluster. Good point. I thought he said he has gauges, but the upper pic doesn't show clearly what he has. I believe I mis-read the way he wrote the question. My bad -- sorry. Link to comment Share on other sites More sharing options...
BookspanS Posted September 8, 2008 Author Share Posted September 8, 2008 Well in that case, how would I hook up an after-market Tach? Link to comment Share on other sites More sharing options...
Pete M Posted September 8, 2008 Share Posted September 8, 2008 Well in that case, how would I hook up an after-market Tach? It'll come with instructions. You'll need to run wires for power, ground, and then something about a green wire running out to the ignition coil to pick up the signal. Tachs are overrated in my opinion (except in the case of my 88 where I'm using it as the speedometer). More important is to get yourself some functional guages so you have a better chance of catching a problem before it gets so bad as to set off an idiot light. Link to comment Share on other sites More sharing options...
deziped Posted September 8, 2008 Share Posted September 8, 2008 How old an aftermarket tach.? Real old ones just used a wire from distributor to the tach. Don't know what digital tachs require. But, new ones come with instructions I'm sure. Link to comment Share on other sites More sharing options...
Eagle Posted September 8, 2008 Share Posted September 8, 2008 A Sun Supertach has four wires. Two are for the light. Of the two for the tach, one goes to ground and the other goes to the negative terminal of the coil. Pretty straightforward. But for the price of a Sun tach you can probably find a full cluster with the tach and gauges, and buy the two sending units you'll need for the swap. Link to comment Share on other sites More sharing options...
BookspanS Posted September 8, 2008 Author Share Posted September 8, 2008 More important is to get yourself some functional guages so you have a better chance of catching a problem before it gets so bad as to set off an idiot light. Thats what I am trying to get is a cluster that will fit into my '86 so i know when something is going wrong Link to comment Share on other sites More sharing options...
Pete M Posted September 8, 2008 Share Posted September 8, 2008 84-86 are a direct swap, 87-90 can be installed by re-using some of the parts from the back of your gauge cluster. I can't seem to find the web page I thought I had saved, but I did find this for ya: http://www.naxja.org/forum/showthread.php?t=921205 Link to comment Share on other sites More sharing options...
Eagle Posted September 8, 2008 Share Posted September 8, 2008 87 thru 90 can also be installed by using an 87 - 90 speedometer cable. The wiring is all compatible, it's the way the cable connects to the speedometer head that's different. Since your MJ seems to have the PRNDL on the steering column, you don't have to worry about retrofitting a PRNDL to a cluster that doesn't have one. Link to comment Share on other sites More sharing options...
88XJSport Posted September 8, 2008 Share Posted September 8, 2008 Hey themz are my full gauges in post 1 !!!!! Link to comment Share on other sites More sharing options...
jteckmann Posted September 9, 2008 Share Posted September 9, 2008 A Sun Supertach has four wires. Two are for the light. Of the two for the tach, one goes to ground and the other goes to the negative terminal of the coil. Pretty straightforward. But for the price of a Sun tach you can probably find a full cluster with the tach and gauges, and buy the two sending units you'll need for the swap. Yup. I just installed a Supertach II on mine a few days ago. For a Renix 2.5, the green splices into the green/white coming off the ICM. I already had the cluster with gauges ... but no tach (giant fuel gauge with warning light/AMC logo at bottom left instead). The tach cost me $20, and I probably could've found a full cluster at the JY for the same price ... but I didn't feel like tearing my dash apart again after finally fixing the rattles. Plus, I just like rockin' that old AMC logo on my dash Link to comment Share on other sites More sharing options...
1987Comanche Posted September 9, 2008 Share Posted September 9, 2008 Will a 4.0 tach work correctly with a 2.5? When I did the gauge cluster swap on my Beretta I had to find the V6 cluster because the tach from the 4 cyl cluster didn't work correctly. If it won't work then I guess I'll have to live without a tach. I have yet to see a 4 banger with a tach in the jy. Link to comment Share on other sites More sharing options...
Eagle Posted September 9, 2008 Share Posted September 9, 2008 84 - 86 you pretty much have to find a 4-cyl or 6-cyl tach in order for it to read correctly. The "2nd generation" (87 - 90) cluster has a tach with a potentiometer on it to adjust for 4-cyl or 6-cyl. Link to comment Share on other sites More sharing options...
rworks Posted September 9, 2008 Share Posted September 9, 2008 Book, I've got a spare instrument cluster if you still need one. I bought 2 for my 87 MJ (just in case 1 was bad) and now I'm stuck with one. Link to comment Share on other sites More sharing options...
1987Comanche Posted September 14, 2008 Share Posted September 14, 2008 So all I need is an 87-90 cluster...sweet! How do you adjust the potentiometer? Does it only have 2 positions or do you hook up an external tach and dial it in to match? Link to comment Share on other sites More sharing options...
88XJSport Posted September 14, 2008 Share Posted September 14, 2008 So all I need is an 87-90 cluster...sweet! How do you adjust the potentiometer? Does it only have 2 positions or do you hook up an external tach and dial it in to match? If the cluster is coming from a 4.0 and going into a 4.0, then there isnt any adjustments needed. Link to comment Share on other sites More sharing options...
xj_dummy Posted September 25, 2008 Share Posted September 25, 2008 The part numbers listed in the link for the oil pressure and temp, would they work on a 2.5 as well? Link to comment Share on other sites More sharing options...
BookspanS Posted September 25, 2008 Author Share Posted September 25, 2008 So all I need is an 87-90 cluster...sweet! How do you adjust the potentiometer? Does it only have 2 positions or do you hook up an external tach and dial it in to match? If the cluster is coming from a 4.0 and going into a 4.0, then there isnt any adjustments needed. how about a 4.0 going into a 2.5? Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now