Am just about finished with the Mercedes om617 swap into my 76 40. My stock alternator wiring is 1 large wire with ring terminal and 2 smaller wires in a plug. The Mercedes alternator has 2 large wires and 1 smaller wire. My understanding is to run both large wires off the alternator to the positive battery post. What about the small wire and the stock 40 wires? As of now I have power to everything without any of the alternator wires (stock and Mercedes) being hooked up. Need to get this figured out so I can get her on the road. Thanks
Almost done om617 swap, alternator question
- Thread starter FJmoneypit
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The smaller wire is for a warning light in the dash that will light up when the alternator is not charging. I have been told don't worry about it. Do a search for om 617 in this form and you'll probably hit the other guys like myself doing the same conversion. Also you may want to go over to peach parts.com and see what other people are doing with the wiring diagrams.
Also, post up some pics of your conversion.
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- #4
Warp drive,
I have been looking for the wiring info but no luck except as I mentioned above. So, I wired it that way and about 3 hrs later was under the 40 and felt heat coming off the alternator. Disconnected the small wire which was tied into the constant hot from the toy wiring for the alternator. Waited awhile to see if the alternator cooled off but still felt some heat so disconnected the pos from the battery. It was not real hot but warm to the touch. I will keep looking, someone has to have done this with the toy wiring to the Mercedes alternator. I will post some pic's when I get a chance.
I have been looking for the wiring info but no luck except as I mentioned above. So, I wired it that way and about 3 hrs later was under the 40 and felt heat coming off the alternator. Disconnected the small wire which was tied into the constant hot from the toy wiring for the alternator. Waited awhile to see if the alternator cooled off but still felt some heat so disconnected the pos from the battery. It was not real hot but warm to the touch. I will keep looking, someone has to have done this with the toy wiring to the Mercedes alternator. I will post some pic's when I get a chance.
Check out my build for pics of what I'm talking about, but the Bosch alternators are non-voltage sensing alternators. However, they require 12VDC to excite and start charging. Not sure what you did, but run a charge wire from the larger of the two lugs to the batter, + starter stud, etc. The small wire needs a 3W lightbulb wired in series with the 12VDC switched power. This is how I was told on peachparts.com and it's charging at 14.02 volts. Hope this helps...
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- #6
Dpv7070,
Thanks, I was just checking out the Mercedes wiring diagram and it shows both large wires going to the starter, starter to batt+, small wire to charge indicator light. Makes more sense to me now, going over to your build right now.
Thanks, I was just checking out the Mercedes wiring diagram and it shows both large wires going to the starter, starter to batt+, small wire to charge indicator light. Makes more sense to me now, going over to your build right now.
Wait - when did THIS happen? Sounds like you've been busy!
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- #8
Rick,
Started about 5 months ago, so not to busy. I am in the home stretch now though. 2f out, check, om617 in, check, fuel, check, electrical 9/10 check. Hopefully I'll have it back on the road in next couple of weeks or less if every thing works out.
Always liked diesel's and it will almost double my mileage or close to it anyway. How's the cluster truck doing?
John
Started about 5 months ago, so not to busy. I am in the home stretch now though. 2f out, check, om617 in, check, fuel, check, electrical 9/10 check. Hopefully I'll have it back on the road in next couple of weeks or less if every thing works out.
Always liked diesel's and it will almost double my mileage or close to it anyway. How's the cluster truck doing?
John
Wow - you're making a lot more progress than I've been. I got engaged, bought a house in North East MD, moved, and am getting married in 3 weeks...so I finally have a dedicated garage, but now time and money are in short supply! Is your 40 fully green yet? The Clustertruck is still exactly that. Rebuilt the axles and converted to 4-wheel disc brakes last summer. Did headlights/electrical/alternator over the winter - put your electrical lessons to good use! Since then I have since been slowly collecting parts to pull the engine, reseal it, and move it to where it belongs in the bay, along with new clutch, new bell housing, etc. Basically doing the whole V8 conversion over again since the PO made such a mess of it. Just trying to determine if the 283 is worth keeping. It has good compression. I'm going to do a leak down test this week to confirm. Currently, I'm back to having carb issues (again). The truck floods out after I drive it about 100 yards, but idles and revs fine sitting still. Annoying...
Would love to see the diesel swap once you button it up! I've tossed around the idea of ditching the 283 and dropping in a GM 6.2 or 6.5L diesel since they're apparently a direct swap for a V8. They're also apparently not very good engines though...so I pretty much scrapped the idea.
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- #10
Congrats on the upcoming marriage. If you can find a later 6.5 turbo I have heard they are not as bad as the early ones, but that is coming from a friend that drives a H1 Hummer w/ na 6.5. No she is still black and green, been more concerned with the swap. Wife wants to park in the garage again. We will definitely have to get together once we are both up and running well. Are you going to the car cruise on kirkwood hwy next month?
That depends largely on if I can get the carb sorted out (or replaced) by then - and when it is next month...If it's August 8th, I'm busy getting married that day.
Rick, if your 283 tests out good then use it, just re-locate it as you plan. Because-- if you use the 283, and move it as planned, and it still doesn't meet your needs-- all you will have to do then is basically bolt in the 6.2/6.5 diesel. As far as the GM diesel being no good, under most circumstances I would disagree. If you are aware of the weak areas, and apply current knowledge to correct those weak areas, you can have a reliable motor.
Now, I will have to add that I don't have a 6.2/6.5 in my 40--yet, but I do have a 1994 Chev K2500 with the 6.5TD. It had 233K miles on it when I got it, 256K now. I do know the history on it from about 165K, and it always ran good. Pre 165K it apparently was set up to tow, and if not prepped and run right problems can be started that will not always be seen until later in it's life, which is where I'm at now. Lots of blow-by, oil useage (most likely caused by improper set-up for towing), and recent knocking that sounds like a collapsed lifter. I am having to do some major work on it now. I don't know yet what I'm going to end up doing to it as I haven't quite arrived at the decision making point, cost is a big factor for me. What I know as the best thing to do, and what I can afford may be two decidedly different things. However, much more is known about how to make them good and reliable runners than back early in their life.
Don
@handcannon - not to clutter up this thread further, but that's basically the plan. If the 283 ever quits it will be a major debate as to what comes next.
FYI - tagged you over in the "can of worms" thread for the leakdown test results.
FYI - tagged you over in the "can of worms" thread for the leakdown test results.
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- #14
Rick,
I am thinking the 1st weekend (sat) in August, will check and let you know
I am thinking the 1st weekend (sat) in August, will check and let you know
