'94 FZJ80 Conversion to Biodiesel / Vege-oil burner.... (1 Viewer)

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Bring in a Mexican, South American or Canadian diesel Cruiser.
 
Tell me how to bring in a diesel 80 and I will do it in a heartbeat
Rusty
 
Tell me how to bring in a diesel 80 and I will do it in a heartbeat
Rusty

bringing one in is not difficult (have it shipped or drive it to the border), the difficult part for most is to pay for making it titleable... :)
 
No way is converting a gasser to a diesel, then bio going to pay off...

This is the long and the short of it. Generally, with cars, you can't spend a little $$ to save a LOT of $$. (I'm talking about multiples of output savings vs. input $$/time, and significant dollar savings.)

LC's are fuel inefficient, as far as passenger cars go. They're heavy, have a large frontal area, poor aerodynamics, and low-stress engine. This does not mean poorly running, it means low HP per displacement. Thus $$ too drive.

-Dan
 
3. latoyota had a 4BT conversion done on his 80 (and another referenced) by Proffitt's, drove it from CO to CA, and reported: "The two trucks averaged around 22mpg on the way back, but we were not gentle on them, cruising at 80-85 mph on the way home over all the passes and everything."

Real life mileage has shown to be anywhere as low as 15mpg to as high as 24mpg. For a lot of reasons I won't go into here, my 4bt conversion has not gotten a ton of road time or milage put on it since it was converted (work, play, and soon to be child). The last tank I ran through I was getting 18mpg, but I have to go up and over a 2000ft mountain pass everyday, 20 miles of curvy road. None of the cars I have owned while living out here have hit their manufacturers listed mpg. Could be my driving style, but everyone I know who does this commute gets lower than average economy. The other truck that came out from CO with me is, to the best of my knowledge, still getting 20+mpg around town, and 23 on the highway and is driven as a DD.
I did the conversion for a lot of reasons, but at absolutely no point did I ever think the conversion was a wise investment of money in terms of savings. It just won't payback like the back of the napkin calculations would want to make you believe. It will be, when I have time to complete everything, a very cool expedition rig, but it will never be my DD or my most fuel effienct car. I should also mention that I am able to get filtered WVO from a local shop for $2/gal. The problem with the WVO is I am seeing a drop of 1-2mpg when I run it, but man does it smell good.
 
I don't know where you guys are getting this extra operating costs thing. I did a swap in my 60 and that thing was totally maintenance free. WAYYYYYY simpler than the 2F, got up to 26 mpg, and ran like a top. Plus, I made my own biodiesel for $.90/gallon, so the payoff was a no-brainer for me.

I had plans to do the same for the 80 but am in restricted funds mode for the time being. It can be done well, for a reasonable price, and with a reasonable return on investment given the right context.

Now, if money ISN'T an option, those wishing to do a swap should wait two years for the release of the babymax, the 4.5L Duramax that is purported to get upwards of 30 mpg for a full size truck. Yummy.
 
I'll have to agree with browndog, I don't see what the extra operating costs will be. Diesels are very simple, just change the filter every so often, the injector pump is usually good for about 150,000 miles, the glow plugs not sure how long they last but guessing pretty long and they don't cost much anyway. What else is there? No plugs, wires, distributer basically nothing to tune up as with a gas engine. Although I haven't even driven mine yet I expect the operating costs to be less than a gas engine.
Rusty
 
Browndog,

You 'made' biodiesel? 90 cents a gallon? If you can make a fuel that will run in a diesel for 90 cents a gallon then, yes - I agree that's the way to go. That basically cuts fuel costs to an incredible 25% of what you have to pay to operate a diesel at the pump.

If you want a bit more information on the extra maintenance of a diesel, check out a diesel forum some time. Myriad stories of injection pumps needing recalibration, or repair - they operate at much higher pressures than gasser injection pumps. Ditto injectors clogging, water separators, etc. Yes, they're simpler on the ignition side but you trade spark plug wires for some other things gassers don't require. They also require more frequent oil changes, etc. Don't take it from me - do the research yourself.

I have a friend who is an accountant that does a lot of work for area small businesses and he's a car guy. I asked him about this once and he told me that a lot of his clients buy diesel trucks thinking they're cheaper and they end up costing the company way more than a gasoline model. I've never had a diesel personally, but have looked into it twice and both times concluded they cost more to operate in the US due to the high price of diesel here. In my area diesel costs nearly 40 cents a gallon more than regular gasoline I run my 80 on and in my travels it seems even more expensive elsewhere in the US.

I believe a diesel vehicle is going to become an economically sensible purchase in the next year or so with the new generation of clean diesels from Europe and Japan because they will be mid size sedans (Honda Accord, VW Passat) getting an incredible 70mpg. They have direct injection, powerful digital control of the cylinder environment, and take advantage of our new cleaner US diesel fuel (it's about time). With that kind of 100% improvement in MPG, they easily make sense. But that doesn't help us much. We're basically contemplating putting an old school diesel in. They're loud, smelly, inefficient, vibrate and need lots of care. This last is important because unless I'm missing something the swaps contemplated by individuals are of older used diesels. Older used engines will not simply run without the half worn parts in it on Day 1 wearing out - some of them quite soon simply because they've already been used in the lower maintenance portion of their life. Now they're in the higher maintenance portion of their life and are being put into an 80. Result? Maintenance. Costs. Downtime.

I don't see it.

DougM
 
I think there are a lot of unaccounted for costs in these diesel conversions and I'll make a comment on Alaska's to that effect since he asked.

Doug- I respect your opinion on this, and I would like to respond to a few things you stated. I bought a diesel MB240D about 6 months ago and I'm beginning to learn the ropes. Granted, I am a newbie when it comes to diesels, but I'd be interested in your thoughts, as well as those of others who'd like to respond.


So, you may find that by the time your 6 year actual real world operation of the vehicle is up, you have spent an additional $1000 on special filters, higher cost oil, shorter oil change intervals, fuel/water separators, diesel injection pump service and batteries.

1. Additional Filters and fuel/water separator- With the spin-on type they can be changed once every year or every other year at a parts cost of about $10 (Ex: NAPA Fuel filter - 3481) and a separate water separator is around the same price. You can also go with a combination fuel filter fuel/water separator like an AMSOIL, where the recommended service interval is 40k mi. Either way, I could easily cancel out any added cost of these filters annually by the lack of having to replace the PCV valve, spark plugs/wires/cap/rotor over that 6 year period.

2. Higher cost oil- I am not the only one on this forum using Mobil 1 in their vehicles. If anything, a switch to Rotella or Delo would be cheaper.

3. Shorter OCIs- many diesel owners on the BITOG forums go for 5k mi. OCIs and are fine, with UOAs (used oil analyses) to back them up. I currently do 5k OCIs now, so if anything I'd be saving money here with cheaper oil.

4. Injectors and Injection pump service-from what I've read, 4BT injectors and injector pumps can go 150k mi. before service. Injector pump service runs around $150 at an independent MB shop close to me, which makes them comparable to fuel injectors on a gasser. According to user "rick d", "$169 to rebuild and renozzle 4 13B-T injectors in Tucson, November 2003." It's true that an injection pump is in the $600 range, but from what I understand, a properly maintained injection pump will last close to the engine's first rebuild (300-500k).

5.
Then, let's toss in a random failure such as an alternator. On a gasser, you could buy one at Schuck's for $80. An alternator on a diesel is perhaps $450.
The 4BT in the Fritolay vans (the most common source available) came with Delco alternators that can be had in the $100-200 price range (did a quick search). Dieselcruiserhead bolted up a 140 amp unit from a '94 Chevy Caprice- cheap and plentiful. Neither OEM nor the other options are any different from the prices of the gasser units from what I can tell.


6.
Atop this, there are some invisible costs such as the total of 10 days the vehicle might sit over this 6 year period while you track down a radiator hose or fan belt or widgit valve for an engine that is scarce, or even never sold here in the US [...] By this, I'm trying to have an accounting made for a specialty vehicle for which you cannot replace a fan belt that tears while you and your family are heading to Grandma's 300 miles away.

Granted, Cummins parts are not going to be as plentiful as those in the 1FZ, but they are a commonly used diesel engine in the US, and parts availability is far from scarce. In addition, checkout this spreadsheet from Proffitts and you'll see that the needed hoses/pulleys/belts/tensioners/filters are available at Carquest. I do not see a lot of one-off parts being used here, and it seems to me you could find most of what you needed at an Carquest/NAPA type of place. Admittedly, if you go the turbo route, there are additional parts and one-offs that can go wrong, but this applies to the rare 80-series turbo owners, as well.


7.
I didn't know about the lift requirement of 4" until now. That is a rollover issue for a DD to me that should be part of the consideration and the truck will no longer fit in a standard garage, or get into a parking garage either.
Apparently, the 4" lift includes a lot of margin. I spoke with the Proffitts guys about this conversion earlier, and was told that it would be doable with my OME 2.5" lift (850/860 w/ an ARB on).

Some people are saying that diesels require less maintenance than gassers. I don't know if I agree with that, but I certainly do not see an added cost of $1000 over 6 years (as noted in the points earlier in this post). However, I do still see the potential for great fuel savings. As I said, I am seriously considering this as an option down the road so I'd really like to hear peoples' opinions along with some hard numbers showing me otherwise.

And, by the way, my 12k price assumed a Cummins factory remanned 4BT, not an engine on its last legs.
 
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I've read that Ford used to have an Excel spreadsheet available to customers that would help potential owners calculate the TCO of gas vs. diesel engines in their pickups considering all sorts of variables. If anyone can find a copy of this, please post up.
 
I think most of the conversions are "old tech" because of the ease of the conversion without having to worry about all the electronics. To me that is a plus, my 6.2 fits in the engine compartment like it was made for it, I can get to everything easily to work on, and even better because it is simple I am actually able to work on everything on it. I do agree though that the new engines are amazing and would love to have one in a new car someday but my plan is to run WVO in a blend and have my cost similar to browndog's and I wouldn't feel comfortable doing that to a new engine. If I end up damaging my 6.2 I can fix it myself for very little expense. I don't expect my operating expenses to be any more than a gas engine, I just don't see how that is possible especially with the 6.2 I am using, parts are cheap and available everywhere. Diesel injectors shouldn't need anymore service than gas injectors, filters more often but as stated they are cheap and with the WVO I will probably be replacing mine every few thousand miles anyway.
Hopefully my story won't change once I am actually driving it!
 
Alaska,

Rather than getting bogged down into what it costs to maintain a diesel vs a gasser, it would be useful to simply say it's a wash - no difference. And we'll go with your $12k costs for you to do the conversion yourself. For fuel economy, let's go with a 30% improvement so that we don't get bogged into a specific MPG figure which has proven kinda subjective - go with 18mpg diesel average vs stock 80s 14mpg average. If that seems unfair, I speak from some experience that a 30% increase is a whopper, especially with the comments I made earlier about the Jeep diesel.

Looking at the Jeep diesel, for example, they achieved a fuel economy increase of 23% (from EPA combined 17mpg v6 to diesel at 21mpg) and they are using an absolutely marvelous state of the art diesel engine to do it. They also did not lift their vehicle during the conversion as would have to be done to a gasser 80 series conversion to diesel - an MPG killer. So, 30% is plenty generous for those considering a diesel conversion, no?

Driving an 80 in my neighborhood costs me $3.00 a gallon for unleaded regular fuel and diesel is $3.40 a gallon. I'll assume I drive 15,000 miles a year so my fuel costs are about $3214/year for the gasser. Decreasing fuel use by 30% means I would save $1070 a year. But wait, unfortunately now I'm buying diesel which is more expensive. The smaller amount of diesel fuel I run through in a year would cost me $2833. Thats a fuel cost savings of about $400 a year.

Since it cost you $12,000 to do, the payoff would take about 30 years. Remember again that I assumed maintenance costs would be the same. You mentioned buying parts at NAPA, etc and I will not argue even though I think I could by pointing out you could also run crap NAPA oil, purchase air/oil filters at NAPA and belts, plugs etc for a gasser saving money at least proportionately.

And this does not account for the months of work the 80 would be inoperable while you do the conversion, needing to buy dual diesel batteries ($), plugging in your diesel in the cold Alaska winters so it starts the next morning, any minor annoyances from the conversion like a nagging exhaust resonance, etc. What do you think?

DougM
 
well, we can debate the mpg savings a long time, I guess. They're all over the map, apparently.

What I'm wondering, though, is what is underlying the rather high cost of conversion. I mean, how much can an old van diesel cost and why is it so expensive to put it in if it has almost no electronics...?
 
OK, triple the fuel savings to $1200. Now the pay off is down to a measly 10 years. In the year 2018 you saved exactly 0 dollars and 0 cents.

I'm sounding like I'm against diesel conversions. I'm not. Just against the popular theory that it's a great way to save operating costs on your 80. My objective is to be sure those 80 brethren reading the diesel threads don't make a huge investment without their eyes wide open.

DougM
 
What I'm wondering, though, is what is underlying the rather high cost of conversion. I mean, how much can an old van diesel cost and why is it so expensive to put it in if it has almost no electronics...?

e9999- check the link in my last post for the Proffitts spreadsheet. The factory remanned Cummins 4BT alone is not cheap at $7k+, but IMHO it's the next best thing to starting with a new engine.
 
I'm not against diesel conversions either, but I have a question about this 4BT conversion.

Back in the Oct. 2006 issue of Diesel Power magazine there was a feature article about a guy who had done this swap on his Jeep YJ using a '96 4BT and TH400 transmission pulled from a wrecked Frito-Lay truck. The guy had also installed a water/methanol injection system to keep the EGTs down. I'm guessing that means either the IP or turbo were tweaked a bit, although the article didn't mention it. Anyway, the end result was a reported 105 hp and 245 ft-lb. That might be fine in a YJ, but how would that work in an 80? That's way less than stock output.

Not only that, but the 1FZ is super-smooth and quiet compared to that generation of Cummins diesel engines. I used to have a '91 Dodge D250 pickup with the old 12-valve 6BT in it, and although it was a good engine, I wouldn't have wanted it in my 80. It would just seem way too...agricultural for such an otherwise elegant vehicle.
 
Alaska,
[...]
Looking at the Jeep diesel, for example, they achieved a fuel economy increase of 23% (from EPA combined 17mpg v6 to diesel at 21mpg) and they are using an absolutely marvelous state of the art diesel engine to do it. They also did not lift their vehicle during the conversion as would have to be done to a gasser 80 series conversion to diesel - an MPG killer. So, 30% is plenty generous for those considering a diesel conversion, no?
It is, but I would also point out that:

1. The base Jeep gas 3.7L V6 engine you are comparing the Jeep CRD diesel to is also state of the art and uses a new 5 speed auto box, so the fuel economy gains from a diesel would not be as dramatic in comparison

2. The Cummins 4BT is a 105-140hp, 4 cylinder diesel vs. the 215hp Jeep 3.0 CRD V6. While it is true that the CRD V6 is a much more modern diesel, Jeep may be going with a higher performance engine at the cost of some fuel economy

That's why I'm still really uncertain on the fuel economy numbers. I just don't think we have enough real-world figures measured and posted up to say what the expected fuel economy is on a 4BT 80 at this time. And this makes a very big difference in the practicality of the conversion and the payoff, as illustrated by my 6.35 year payoff calculation vs. your 10 years. Even giving you the 3x fuel savings you proposed in your last post, that still leaves almost a $500 / year gap in your predicted savings vs. mine ($1200 vs. $1695). Part of this is also due to the difference in diesel vs. gas prices (discussed below).


Driving an 80 in my neighborhood costs me $3.00 a gallon for unleaded regular fuel and diesel is $3.40 a gallon. [...] Thats a fuel cost savings of about $400 a year.
Here in SoCal, diesel was around $3.00 when gas was $3.39-3.49 in the summer. In the winter, diesel is around the price of premium. That's why I'm not going with 3.00 for 87 vs. 3.40 for diesel, and instead am calling it even. I guess you aren't seeing the cyclical prices over there?


And this does not account for the months of work the 80 would be inoperable while you do the conversion, needing to buy dual diesel batteries ($), plugging in your diesel in the cold Alaska winters so it starts the next morning, any minor annoyances from the conversion like a nagging exhaust resonance, etc. What do you think?
DougM
The months of work would be an inconvenience, but also a one-time price to pay for getting what would largely be an all-new drivetrain, and the process would be fairly painless with a second vehicle. The dual batteries are more expensive, I'll give you that, but not a lot more than the pricey dual batteries (read: Odysseys, Optima yellows, etc.) a lot of people are using on their gasser 80s here on the forum. Pretty much everyone in Fairbanks plugs in their gassers for a large portion of the winter, anyway, so no difference there (plus the whole fam is out of AK now..heh) Nagging annoyances, I would hope, would be figured out by those pioneers before me (wishful thinking, I know). ;)

BTW, the calculations on the tradeoffs of a diesel conversion should also consider what you would get for your 1FZ/tranny combo when you sell it, as well as the cost of a headgasket job, which is something you would probably need to do if you were going to keep your 1FZ (if not already done).

If it sounds like I have my mind made up about this, believe me, I don't. But this type of back and forth is quite helpful in assisting me (and others, I'm sure) to get a lot of the pros and cons associated with a diesel conversion out on the table before making a decision.
 
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I think the best thing about all of this is that we are all justifying our reasons for driving/keeping our Cruisers. As for me I guess I look at it funny, I seem to forget the price of the vehicle (payments, conversion cost, etc) when I get to the gas pump. It was frustrating to me to have fill up every 250-300 miles, with the diesel I might make it 350-400 miles before fill-ups. My main goal though is to use WVO to cut my cost to less than $1.00 per gallon, plus at the same time my emissions will be virtually zero. Of course on the other hand you can save the environment by driving our old cars and keeping them from the salvage yards and conserving our resources by reducing the number of new cars being built. If I would have had to pay $12,000+ for a conversion plus buy the Cruiser I am not sure that I would have done it, or could have justified it, but since I was planning on doing it myself, was lucky enough to find a Cruiser needing an engine and decided on the GM 6.2 I will come out cheap enough I can justify it even if I were to run it on diesel. There are a lot of ways to look at it and great arguments on both sides but like I said before the best thing is that it keeps more people driving cruisers.
 
I'm back. I think one of the reasons swaps are appealing to many of us is the ability to run biofuels. As I stated above, I made my own biodiesel (a very simple home version of transesterification) for $.90/gallon--the only costs are for your methanol and catalyst, the veggie oil is free. Making the economics work in an 80 are difficult because they are so heavy and full-time 4WD, but the ability to burn an alternative fuel and make it yourself changes the whole equation in my mind.

Another issue that keeps getting kicked around is the cost of doing a swap. I did my 13BT swap for a grand total of $8500.00 doing it myself. That's for a factory diesel! Granted, factory motors for the 80 are a bit more expensive, but you can get more for your 1FZ than you can for a high mileage 2F. As with mileage, the numbers are all over the map.

My take home messages are these:
1. There are multiple reasons for doing a swap, some of which may include fuel economy, alternative fuels, and cool factor.

2. Swaps can be done in an economically efficient way, but not all swaps will.

3. Some of the diesels available are actually quite pleasant to drive (1HZ among them) in terms of vibration, smell, and smoke.

4. Swaps for the 80 are considerably more complicated and expensive than other models (with a few exceptions).
 

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