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Opinions needed - Performed Optical Bump

Just bench tested the alternator and it works. I’m curious though. Does this style have needle bearings in the rear or standard roller bearings. When spinning with the drill there is no noise but just a slow spin with my fingers makes a light squeak squeak. Is it has roller bearings I’m wondering about opening it up and greasing them for good measure
 
You are mighty fortunate to have an auto salvage that has 6.5 units.
There is 1 auto salvage here, they have two 6.5 trucks in the yard, one of the owners also has a GMT400 with a 6.5 and He will not lat anyone scavenge parts off of either one of those.
Lol my wish list it to pull ones of these motors for a rebuild project but finances isn’t letting me. I had priced one out to about $4-500 plus getting them to pull it out for me. It’s at a WrenchaPart in San Antonio
 
Nothing to worry about. Bust open that alternator, knock out the rear bearing and drive in a new one.
IIRC, the front bearing might need to have some grinding done on the front housing to get it removed.
It just sort of seems that there may also be a three fingered spring loaded retainer to hold it too. You will know once You get the bolts removed and the front half separated from the back.
Sometimes the squeak can be caused by the brushes. The NAPA store here carries the brushes and bearings for most any alternator, I know I have kitted the alts for the smaller pickups, 1500 series.
 
The thought I had with the pcm was to maybe if I could one day afford it. Send it in for a tune for my truck while keeping mine for an original spare! I know the truck I pulled it from was a 94 vin F with an automatic transmission not sure if it was a 4l80e though

I’m curious if I were to use the GMTDscan and do a memory dump on mine and this one of someone can read the data to compare them
 
The donor truck is a 4L80E, it's the only automatic GM ran behind the 6.5TD. And actually, it's not the PCM/ECM that's programmed on 94's and 95's, it's the removable PROM chip inside, under the small rectangular cover on the bottom, that gets reprogrammed! Now, the ECM itself can go bad and throw the dreaded OBD-1 death code, but it is that PROM that controls all the running parameters like fueling, shift points, speed limiter (if a C&C commercial vehicle), etc.

96+ were the sealed unit OBD-II PCM/ECM that required a reflash of the whole unit.

So, you can just buy a reprogrammed PROM chip exchange, that one reprogrammed, or one outright. There used to be a member or two on here that did that, one even offered a multi-tune selectable chip option, but I'm not going to open that can of worms. I believe Heath and Kennedy both offer the OBD-I PROM as +40 and +80 HP options (upgraded intake, exhaust and gauges needed for the +80) as does SS Diesel and others. BUT not all tunes and HP claims are equal! Caveat emptor!
 
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I have placed an order for a new fan clutch so I can install the 9 blade fan and get away from my OE 6 blade fan. it should arrive on Saturday. the clutch I ordered is a knock-off one just to get me by for now, as I don't want to dump money on a good clutch now when later I plan to upgrade the pump then buy a good spin-on clutch.

Good dog.. Stupid F will likely not make that mistake again. :angelic: Might need some signs beware of dog - who refuses to take his meds... Heh-Heh: Beware of anti-vaxxer dog would be a funny sign as well. :smuggrin:

Now a PSA from a carnage thread winner. Go buy both the 6.5 engines from the junkyard, NOW! In the carnage thread the first scuffed, cracked, and burned through piston of mine you are looking at is from a bad 6 blade fan clutch. The engine went to the scrapyard with dammed 6 blade fan and worthless clutch still bolted to it.

Otherwise, instead of buying some engines, I suggest you return the knock off clutch and simply don't bother or do it all at once the right way. The spin on is the best, but, I got by with the four bolt HO water pump and low temp KD fan clutch. There simply is no half-assing it on the aerodynamic body that doesn't have good airflow through the stack to begin with. The damage to the engine from getting it too hot is rings loose their temper and blow-by, cracks, blown head gaskets, cracked heads, and scuffed pistons. The RED line is 210 on the gauge that GM omitted red ink on using gas engine temperatures as a red line. One doesn't overheat ANY IDI engine, period. CAT, Ford, etc.

There are many proven ways to do the cooling systems well on these trucks now. Using one of them will save you an engine. No, you won't be watching the gauge until it's too late when things go wrong with a knock-off unknown part.
 
Yup. Overheating did in the IDI diesel in my Audi 5000. Rings lost temper and blow-by/oil consumption got so bad that right before it wouldn't start any more off of the glows in summer because the compression was too low, a 120 mile round trip on the Interstate used a full quart of oil! That was a 2.2L 5-cylinder turbo diesel engine!
 
Got the ad244 alternator installed no fabrication really needed except for the top bracket I just happened to have a short piece of flat steel in the garage that already has two holes in it about the same distance as the original bracket. Jut had to enlarge the holes. Temporarily wired in the two wires for the side plug cranked up and tested. I didn’t run it long enough to heat everything up but just running under full load with everything on max the alternator was pushing out 60 amps at 14.3 volts at idle. I’ll heat it up good tomorrow and see how well it does.

I do have a question about my tensioner though. I noticed before I pulled the belt off. The marks were getting close to the max range. When mounting the bigger alternator I knew the pulley was a slight bit further out so I didn’t swap in the diesel pulley for the test. After mounting it and installing the belt the tensioner was a lot further away from the max so I thought good. After starting it up and al. The tensioner went back close to where it was before I changed the alternator! The belt is only a few months old. I took a couple of photos. Is the belt being pulled too tight? I still want to go back and swap in the larger diesel pulley but that’s gonna make it pull even tighter if this is the case!
 

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Do you have a rear support bracket on the alternator? The case will snap in half if you don't from Diesel vibration.
 
Do you have a rear support bracket on the alternator? The case will snap in half if you don't from Diesel vibration.
I still have the rear bracket from the old alternator there but only the bottom bolt lines up. There isn’t a rear mount point on the alternator. I did pry and tug on everything and seemed solid. I was thinking the same thing. Maybe I can bolt something to the upper bolt since it has plenty of thread to use and to the intake somewhere
 
My 1995 with a CS 144. Note the rear bracket required to prevent the case from snapping in half. My 1993's rear bar went to the intake stud without the sawed-off OEM bracket.

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Don't forget to upgrade the charge wire.
Minimum 10 gauge. Preferably, get some of that 6 gauge OFC audiophile power cable (it can handle a 200 amp surge and 120 continuous) and gold-plated crimp-on lugs and run it directly from the Alt's Positive terminal to the nearest battery Positive post, using the terminal bolt (either top or side) to secure it with to the battery.
 
And do a forum search, make sure that the pulley diameter is correct.
Pulley on My alternator is too small. It was too small when I bought the truck. PO had installed a reman alt and didnt swap out pulleys.
I should get the proper unit so the tack reads correct.
 
Yeah, too many big chain parts stores sell a "High Output" Alternator option for our 6.5's that is like 10 Amps higher output than the OEM stock standard alternator is. Only problem is is that it has a smaller diameter pulley to increase alternator RPMs at idle and thus amperage, but it also throws off the pulse signal to the tach. Nine times out of ten the parts monkey at the counter looking at the computer isn't even looking at the right listing for the 6.5 anyways.
 
I swapped out the pulley this morning with the diesel pulley from my old cs130. Tach is 100 rpm on the high side but it’s good enough for me lol. Rechecked the output and it seems steady pushing 57 to 60 amps at 14 volts at idle with everything on 😊

now finishing up some odds and ends before the trip like wiring in a usb charger in the back seat for the kids and cleaning out my tool box and organizing my spare parts lol
 
Ok got a question on the power wire on the alternator. I know you guys are recommending a heavier wire. The wire on my truck looks to be a 6 gauge with a fuseable link on the end at the battery. Today I had the radio playing for a long while. When I cranked it up I noticed my voltage gauge was a little low so I grabbed my meter to check things. I found that the fusable link was HOT but not the wire itself . A little too hot for my liking so I want to run another power wire to the junction box but I’m unsure weather to get another link wire or a heavy fuse for it. If this alternator is capable of say 150-200 amps, what size fusable link wire or size fuse should I use? I’m a little uncomfortable just running a straight heavy wire without having some kind of protection from a meltdown!!
 
I was thinking about one of these circuit breakers to run inline with a 4 gauge cable from the alt to the junction box. I have one like this on my stereo amp. Any thoughts about it and is this large enough in amperage?
 

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