Dodge RamCharger Central banner
1 - 14 of 14 Posts

·
Registered
Joined
·
48 Posts
Discussion Starter · #1 ·
OK, as many of you know i had a complete 87 ramcharger and i bought a 93 ramcharger canyon sport le edition and the 93 had no tranny so i took the tranny out of my 87 and put it in my 93 and it bolted up right and i got the project done and go to start the truck and it doesnt start (no spark to plugs). i figure no biggie and start diagnosing and find out i have no power to the coil so i keep tracing back and come to an auto shut down relay and it was staying open when it was supposed to be closed and so i replace the relay and find out that wasnt it so i unplug the relay and run jumper wires over it and get power to the coil and power to the distributor cap but no spark so i go all out and replace the coil, plugs, wires, and distributor cap and rotor and that didnt do it. so i keep diagnosing and after three weeks with a multimeter and scratching my head and reading my haynes and chiltons manuals cover to cover i find something i over looked called the crankshaft positioning sensor and the 93 has it and the 87 doesnt. and that sensor reads the notches on the flexplate and tells that to the pcm and allows the motor to run. so i have a complete project but it wont run because i dont have that sensor. so its not like i can jsut get one and plug it in. i would have to cut the bellhousing to make the bracket to be able to install this sensor (because it installs between the bellhousing and the back of the block). the tranny is a 727. so im stuck im hoping there is an easy way that i can just bypass this sensor and be able to get the truck running but if i cant bypass it i will have to replace the tranny with one from a 93 ramcharger. and that could get a little costly. so hopefully somebody on here will know a way to bypass that sensor so i dont have to find a new tranny buy it and replace it again. i have talked to a couple people so far and they say the sensor is not needed but i guess it really is because the truck isnt runing and i have absolutely tried everything. what it says in my haynes manual about the crankshaft positioning sensor is this: the crankshaft position sensor determines the timing for the fuel injection and ignition for each cylinder. it also detects engine RPM. the crankshaft position sensor is a hall-effect device that is mounted on the bellhousing and detects notches in the flywheel(manual) or flexplate(automatic). the engine will not operate if the SMEC/PCM does not recieve a crankshaft position sensor input. so i found my problems and would really like to find a way to bypass this sensor. because i really dont want to buy another transmission and replace it just for one tiny ass sensor. so if you have any idea on how to fix this problem or know anyone that does please please let me know because i am that close to being done on my 93 ramcharger project. thanx for your time and im sorry it was so long but this is the last problem in this project i am doing.
 

·
Premium Member
Joined
·
5,548 Posts
The 727 can me modified for the sensor. It bolts to the back of the engine block. It should still be there unless you took it off. Its probably also crushed. Its also very needed and can't be bypassed with stock computer. The tranny just needs a notch made in it and a rubber grommet. You could probably get the dimensions and placement on the notch from a wrecked truck and get the grommet from that also.
 

·
Premium Member
Joined
·
9,424 Posts
Question: Rather than being an actual "position sensor" (as in degrees of rotation location), doesn't that sensor simply read true rpm, and trigger the SMEC..?

How many magnetic pulse points are there on the flywheel ? One ? or Eight ?
 

·
Registered
Joined
·
48 Posts
Discussion Starter · #4 ·
The flywheel thats in there right now has none. because the entire tranny is from my 87 ramcharger so it has the torque converter and flexplate and all that stuff tfrom the 87. but i have an idea for a solution if all it is are magnets on the flywheel to trigger the sensor wut if i buy a sensor plug it in and stick a magnet to it and try to run it like that or will it not work or burn something up.
 

·
Premium Member
Joined
·
5,548 Posts
I'm not trying to be anal here but dont' waste your time trying to bypass it or rig it up. Of all of the sensors on your truck the crank sensor is the most important one. There is no way around it. You could do away with it by using a crank sensor on the front of the engine and Accell's DFI fuel injection computer but all that is going to cost you $1500. There is 8 positions on the flywheel btw. No magnets on it. just slots. The magnet is on the sensor itself. All you have to do is get the correct flywheel. Grind a slot in the transmission and buy a $60 sensor and be done with it. Don't make it harder then it is.
 

·
Premium Member
Joined
·
9,424 Posts
Thanks 300le...
So the slots in the flywheel are the triggers, due to the change in field strength when the slot passes the sensor (just "oppositely" comparable to the fins on the distributor shaft in the 'old style' electronic ignition).

Having understood that, I absolutely agree that it's cheaper/better to replace the flexplate, and match the mounting location for the sensor, than to fight with other solutions.
 

·
Registered
Joined
·
30,099 Posts
that or just drop a carb and intake on it and be done with it / the placement of the sensor on the block and air gap is critical to fire the injectors / if yer off by more than 2 degrees you could blow the heads off / l,d get the right tranny or do the carb thing
 

·
Premium Member
Joined
·
5,548 Posts
His engine should already have the mounting for the sensor. Probably has half a sensor still there.
 

·
Registered
Joined
·
48 Posts
Discussion Starter · #9 ·
Ok, if anybody could give me detailed instructions on modifying my tranny to make this work please get them to me because i would love to ge tthis thing running. it had no sensor on it the guy i bought the truck from sold the tranny to a friend ogf his so his friend took the tranny and rear driveshaft and i took the sensor is my guess because it is gone wasnt bolted anywhere and isnt smashed. i want to keep it fuel injection if i could. and that aftermarket sensor for the front sounded good till u said $1500 and there is no finding a tranny for this truck around here every junkyard i find has no ramchargers or ram pickups anywhere close to these years. so if anyone can find a solution please give me a detailed and full instructions on how to fix it please. because if all i ahve to do is grind on my old tranny and install a sensor and then wire it up i will do that. so if any one knows how and can take pictures if possible and give me full detailed way to do this i will do it.
 

·
Premium Member
Joined
·
5,548 Posts
Go to a tranny shop and take a look at any of the Dodge tranny's they are rebuilding (trust me they will have them). All 92 up trannys should have this notch. The OD tranny is notorious for going bad so the tranny shops should have some laying around or getting ready to rebuild. You then can get the measurement and placement for the notch. It is about the size of your thumb.

This pic is of the sensor in the correct location on the back of the engine block.
 

Attachments

·
Premium Member
Joined
·
5,548 Posts
Here is some pics I pulled off the net and put together to sorta show the notch. These aren't the best pics but its all i could find.
 

·
Premium Member
Joined
·
8,689 Posts
ya it would seem that every tranny in that year range should have it, wouldnt have to be nessessairily from a 4x4 RC
 

·
Registered
Joined
·
48 Posts
Discussion Starter · #13 ·
Dodgeman said:
ya it would seem that every tranny in that year range should have it, wouldnt have to be nessessairily from a 4x4 RC
Yeah it would have to be a 4wd tranny so i can have a 4wd truck but it would be from either a ram or ramcharger from those years.
 

·
Premium Member
Joined
·
5,548 Posts
Any truck tranny after 92 will have the notch your looking for to get the measurement and placement.
 
1 - 14 of 14 Posts
Top