Cam's FJ60 Gets a Heart Transplant
- Thread starter FJ60Cam
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- #642
I may have done that yesterday. But I am a trained arsonist. I only shot gas across the driveway. No fire
Cam,
For the record, can you post up weight difference of the 2F+H55 combo versus the Vortec+auto combo. It's not obvious to me that the later is significantly heavier, although having your front springs sag should be proof enough of that. Just would like to see some quantitative info to back it up.
And, knowing nothing about these kinds of swaps, the fuel pump you installed during the swap must have a return line that bleeds off excess fuel back to the tank, right? Just like on FJ62's?
For the record, can you post up weight difference of the 2F+H55 combo versus the Vortec+auto combo. It's not obvious to me that the later is significantly heavier, although having your front springs sag should be proof enough of that. Just would like to see some quantitative info to back it up.
And, knowing nothing about these kinds of swaps, the fuel pump you installed during the swap must have a return line that bleeds off excess fuel back to the tank, right? Just like on FJ62's?
Cruiserdrew
On the way there
You should actually see more like 14.5 - 14.8. That will lead to quick recharging of your batteries. 13.0 is more like a float voltage after the real charging is done. We didn't really get to this, but it's still an issue.
- Thread starter
- #645
I'm not sure of the weight difference. I've heard that the motor is 100+ lbs lighter. The transmission & adapter are probably the same or a little more than the H55.
I'm not saying that this combo is heavier than the old. Only that my old springs were shot from previous abuse and that the heavier springs are now recommended up front (with a 2F, I presume).
The first oil pan (Camaro) was much thinner up front, which is where my new pan (muscle car) contacted the housing.
Without the bumper on, the Camaro pan did not hit (but had zero clearance at the back of the pan near the diff flange). Once I had all the weight back on and greased the springs up, their sagginess revealed themselves.
According to the tape measure, I now have more clearance for the pan than from the bumpstop to its contact patch. But just barely.
I do have a return line. It is part of the filter/pressure regulator that is in the feed line just downstream of the pump.
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- Thread starter
- #647
I prefer the female kind, but I'll take what I can get!
- Thread starter
- #648
I did some internet sleuthing, and it sounds like my alternator should be controlled by the ECM, by way of the BCM (body control module). BCMs are generally (99.999% of the time) eliminated from these transplants to make a clean standalone harness.
It sounds like mine is running on the "default" voltage, which is the 100% duty cycle output of 13.8V. I'm seeing fluctuations (via the scanguage) of 12.8V - 13.5V which, I'm guessing, include some losses from the 13.8V.
One solution I found was to switch to the earlier 4-wire alternator and add the appropriate wires to get the internal voltage regulator to actually regulate. The other was to live with it.
I'm holding out for a TrickyTcustoms standalone module though
Here's a few tidbits I found...
http://ls1tech.com/forums/conversions-hybrids/1333228-2-wire-truck-alternator-wiring.html (see post#11 for all the gen iv alternator tech you ever wanted, including the "default" voltage)
http://67-72chevytrucks.com/vboard/showthread.php?t=607928 (see post #8 for the 4-wire suggestion)
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- #651
No idea on the leak. I'm going to drain the t-case, re-fill and check it every so often to see how long it takes to fill up. It might only happen on long, steep, offroad climbs, which there were several. That's when the fluid would drip out the tailhousing when it was out of the truck (when it was at an angle). I really don't want to have to dive back in to the t-case, but it looks like that's the reality. At least it can be pulled separately from the transmission now, thanks to the adapter.
No thread yet. @concretejungle has started one (https://forum.ih8mud.com/threads/la...subaru-or-a-land-cruiser.861033/#post-9776079), but is really slacking, so I may have to start one anyway! When I do, it will be here in the Mississippi clubhouse. That is the most logical place to put a trip report for a group that came from CA, AZ, TN, & NC
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I think this is spot on. Earlier, when you said your alternator was only putting out 13V, I assume this was based on measurements at the battery or further 'downstream' where the scanguage is connected. If so, the alternator is probably putting out the standard ~14V and the delta you're seeing is simply due to voltage drop in the system. I'm not familiar with the newer model alternator you're using or the wiring harness modifications that have been made, but I'd guess, with the elimination of the BCM, the alternator now has the remote sensing input disabled/disconnected...effectively removing the regulating abilities of the internal regulator. Ideally, this remote sensing input would be connected to the electrical system downstream from the battery. When 13V is sensed there (like your scanguage is registering), the internal regulator will allow the alternator to boost the output to say 15V until the ~14V is sensed in the system.
haha i'm slacking because i can't post the bad a$$ pics! They are too big for mudwidth, but now i have a plan so i should be able to get the slack out and get back at it.
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- #654
Please hurry so I can steal them for my own thread
BTW, when I got home i told JFZ80 about your leaking fluid issue and he said that was common with that swap, so i'm assuming there is a good fix for the issue.
- Thread starter
- #657
I've since heard the same thing too. Especially on the 80-series swaps.
It looks like it would have to pass by the sealed bearing / spud shaft...
... and then under the splines...
- Thread starter
- #659
That was entirely possible with all the mud. I'll check out the tranny vent. Actually, I'll just extend the line to a cleaner location.
I'm hoping this is the case. The trans fluid level shouldn't be high enough to fill this except during extended climbs.
I'm hoping this is the case. The trans fluid level shouldn't be high enough to fill this except during extended climbs.
The newer Gen IV GMC alternators, from sometime in 2005 onwards, don't use a voltage sense wire. Instead they use a device called a Generator Battery Control Module (GBCM) that connects to the negative lead of the battery. The GBCM continuously monitors the amount of current that is being drawn from the battery and then communicates that to the ECM (via the Body Control Module - BCM) so that the ECM can direct the alternator to charge the battery based exactly on the amount of discharge that has occurred. In other words, instead of sensing battery voltage to determine the battery's state of charge the newer charge control systems directly measure how much power has been drawn from the battery and then replace exactly that much back during charging. The monitoring works whether or not the motor is running. So if you use a bunch of your battery reserve playing your stereo with the ignition switch in the acc position, the ECM still knows how much charge the battery needs to recover to a fully charged state.
But Cameron's motor swap eliminated the GBCM and BCM, and so the ECM has no way to know the state of charge on the battery. He needs to fix this before he ruins his battery, or at least shortens its life. This thread (discovered by Cam) shows what needs to be done: http://www.trifive.com/forums/showthread.php?t=116343
Lastly, if the ECM doesn't have the GBCM/BCM signals that it needs, it defaults to telling the alternator to just run at a constant 13.8v output, which is exactly what is happening with Cameron.
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