Hi fellas,

I was hoping to get your help with something; I work for a technology company and we are trying to do a prototype testing for a mobile laboratory. I have offered up my 1987 Jeep Wagoneer XJ Limited to be used as the test vehicle for here in the states rather than buying an expensive vehicle just for testing here and my company has accepted my offer. I have already tested the concept over in Ghana, Africa using a Land Cruiser and an upgraded alternator - 360 amp output.

We will be running some lab equipment in the back that is rather power hungry, a small air compressor, a computer, and a laser printer - all through an inverter, of course.

That said, this alternator was a bit overkill, but I think we do need something in the 250-270 range. I've found the "mean green" HO alternator but it only claims "up to 300%" above stock. Well, that is a pretty dicey claim and I've already called them up to ask for clarification. I believe the OEM output for my Jeep was 100amps...so that would mean their alternator should put me right in the range I'm looking for.

Does anyone know of another manufacturer that has an HO alternator that puts out in that range?

So that covers the first issue. The second issue is the grounding - I need to do the Cruiser54 upgrade to my grounds before I install the equipment, of course...does anyone know if the KellysWIP guy is still making the kits? It looks like his site is dead. Does anyone else make these kits?

Cooling: Do I need to worry about cooling? I have upgraded my entire cooling system to be an "open" system with a new aluminum radiator, new water pump, coolant, overflow, thermostat, etc. It runs great and I never get over 195 or so degrees, even in the hottest part of the summer here in Dallas. Should I look at installing a pusher fan in the front?

Increasing the idle: The HO alternator won't do bunk for me at idle, so I need to have a switch that will allow me to increase the idle while stationary. Does anyone know of a kit or a way I can modify my Jeep to increase the idle on demand? On the Land Cruiser I just installed an up idle kit and at the flip of the switch I got an extra 500ish RPM, thus higher electrical output.

Dual Batteries: Should I equip my Jeep with a secondary battery? Is there a kit for this or a wiring diagram?

Lastly, the equipment and mounting system is going to weight somewhere int the 500lb range. I intend to put in air bags to assist in the weight balancing, but I wanted to get some feedback from you all on whether this is the better plan or if I should just get heavier duty rear springs? Keep in mind this isn't a long term deal so I don't want to have the jeep riding around like a dump truck after the equipment is removed - that's why I'm thinking airbags. Thoughts?

Thanks everyone, greatly appreciate your assistance!

-Matt

 

XJwonders is a user on here that sells upgraded battery cable kits, you could contact him. Also hopefully someone will chime in about the high idle but I know it can be done, and isn't too complicated. Sounds like an interesting project

 

I received an email stating I had a response and can see in the main forum page that I have a response, but when I look in here I can't see any responses from others...anyone else having that problem?

 

It happens on occasion it should appear after your post or this one. If not he said that XJwonders is a member here and sells upgraded battery cables and stuff, he also said that there is a way to do the high idle switch, but IIRC that's only for the '91+. I'm sure there is a way to do it however.

 

Thanks PNW!

That said, I was able to read his message in my email so I have already reached out to XJWonders. I think he's going to be able to hook me up with a cable kit that will suit my needs.

I think I'm going to go with the Mean Green 200 amp alternator. There is another company, DB Electrical that claims to have a 220 amp alternator, but the reviews aren't fantastic and the load tests seem to state that the output is below what they claim. I think it'll just have to leave out the laser printer (huge power hog) and run a dual battery setup.

As far as the high idle goes; I'm going to run a manual choke cable to the throttle body and have a good ole fashioned manual up idle for this project.

As per XJWonders advice, I'm going to forego the pusher fan since I know my cooling system is in good order.

I'm also going to go with the Air Lift Rear Suspension air bag kit: Air Lift Kit

Anyone else have anything to offer...anything I'm missing or need to consider?

 

I have a fairly large inverter on my work truck. It has a separate battery, and uses a battery isolator to keep it separated from the trucks other batteries. That will be your best option. Be sure to calculate your wattage needs before making your inverter purchase. I would go into further detail but I am home and my wife won't stfu.

 

Good thought Mike, I think I will look into the battery isolator.

I've actually already run this prototype setup over in Ghana, but it was in a Land Cruiser that I had installed a 360 amp alternator - and it was already equipped with a dual battery setup. The inverter was used was a 3000 watt and it is the same one we intend to use in my Jeep so I think we'll be ok there. My biggest concern is whether the 200 amp alternator would work for the power draw we are likely to see. I think the most we saw was 160 amps or so, but that was only when the laser printer was kicking on at the same time the A/C compressor kicked on.

 

I find a dime works good for bumping up the idle. I have a 90. A dime between the throttle and the stop bumps the idle up to about 2000 RPMS. If a different number is desired, you can use a feeler gauge. A little experimentation will be necessary to find how thick the feeler gauge needs to be. Involves opening the hood to install, but probably wouldn't be a bad idea to pop the hood during prolonged periods of idling to help with heat management.

 

Curious, what are the specifications on your air compressor? Unless you're using a very high efficiency pure sine inverter, would you be better off with a DC unit? Even better, if air conditioning is not required, the air conditioning compressor can be converted for straight air use instead of refrigerant.

Unfortunately 1987 didn't have any factory elevated idle mechanism. People have been known to use bicycle shifters as hand throttles to increase idle RPM from within the cab.

I'm not aware of any specific kit for running dual batteries, but you can use a device called a battery isolator to connect one or more batteries to your system. These will let you run down an auxilliary (bank) of batteries without depleting the starting battery. They're used commonly on RVs. Product manuals will have wiring diagrams

 

I think Dirtbound Offroad makes a dual battery tray for the XJ. You will need a short-ram intake for it to work though (mounts where the factory airbox is)

http://www.dirtboundoffroad.com/univ...iver-side.html

Cowl intake would make sense and can be done pretty cheaply (relocates the engine filter to the cowl area, which is much higher than the factory intake).


You could probably easily custom mount a second alternator if you wanted to, but would take some custom fab. Most people run it where the A/C compressor is, but you probably want that
Mean Green is going to be as good as you will get for a stock-ish replacement. You can fit a Durango or Grand Cherokee ZJ alternator with minimal effort - they might have more powerful options for those vehicles.

For extended idling, I would throw some hood vents in for good measure. Definitely make sure the cooling system is up to par (including the fan-clutch).
Increasing the idle speed, you might need to install a hand-throttle as mentioned (for the 87).

Might as well consider converting the interior lights to LED for lower power draw, consider installing upgraded 4-hole injectors for a bit better efficiency (along with making sure everything else is up to maintenance).

Off-road/area lighting is always a nice addition and pretty cheap to do.

 

I would also consider using one of these if the alternator will not run a big enough inverter for your needs. They are fairly quiet. You can mount it on a hitch rack.

http://www.northerntool.com/shop/too...3983_200623983

I also thought the formula for an alternator output would be amps X volts. So a 200 amp alternator at 12.5 volts would put out 2500 watts. Not sure if that calculates direct into what size inverter it would power, factoring in what ever else the alternator is running.

 

Cables. www.meanlemons.com

 

That's a great idea as well. The idea is that I can bump the idle up when stationary. It'd be preferable to not have to pop the hood each time to insert a dime, but it's certainly a great backup plan!

We are running an AIMS Power pure sine inverter, 3000 watt. The equipment we are powering totals to nearly $100k, so we want to clean the power up as best we can before it gets to the instrument. Additionally, we can't remove the A/C as part of the issue is heat; if one of components of the device gets too hot then we start to experience a delayed or stunted flow of the carrier gas. That said, this issue may be eliminated as we are (and I am strongly pushing for) the use of canisters of the carrier gas - non-flammable fellas

I do need to look into the battery isolator setup as I think that would be a good idea. I'm going to speak with our electrical engineer about it.

Thanks Cruiser, as always. I think I'm going to go with XJWonders' product, he's been very helpful!

 

Thanks for the feedback. I'll look at that front battery tray, but I almost think that running a second battery in the back would be easier and would lessen the chance of issues by using the stock airbox setup.

Definitely considered the second alternator idea, but I really can't remove the A/C - the equipment must have it to keep within the operating range.

I'm confident my cooling system is up to the challenge as it is completely new, as is the A/C system. I've done lots to this Jeep as it's my daily driver - I just like older vehicles - that said, I don't want to be stranded so I've made sure she's a strong runner. That's a good idea on the LED conversion. Already did the four hole injectors and the "newer" ECU. Still trying to find a darn '88/'89 TCU though. No luck thus far.

That's funny you mention the generator; that was initially my idea, which was shot down at the beginning of this project. Our last conversation yesterday before I walked out the door was with the Systems Engineer who proposed this solution. Now, playing Devil's Advocate, my concern with this mode of power is that many (cheaper) generators tend to have fluctuations in their output, so we'd have to rig something in-line to clean up the output before powering the instrument - as I've already mentioned, we are looking at an $80k instrument w/~$20k in support devices, so anything that will even possibly cause damage or mess up the readings is of concern.

Also, the hitch mount idea would work, but that is also where we will be running the tests on the device, out of the back, so we'd have to struggle with that each time we stopped, unless we fabbed/found a swing out hitch option. Either way, I think we are probably looking at a more expensive solution by using a generator; but hey, I'm totally open to the options that the engineers float.

 

If you can get away with 175 amps, then a genset might not be necessary, but beyond that you might want to look into getting a genset.

I bet you could get a 4x4 shop to rig up a trailer hitch mount that swings out of the way, but it's alot of weight aft of the rear axle regardless. Mounting it on the roof could be an option depending on how heavy they are, but cumbersome. Really, unless you have a pickup truck, hauling a generator around is less than ideal.

If you end up leaving the engine running with the tailgate open for long periods of time, you may run onto the issue of exhaust blowing back into the cabin. Happens to me quite frequently (the cold Temps make it easier to see due to the water vapor in the exhaust gas. Never seen stacks on an XJ yet
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