Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

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JoeIsuzu
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby JoeIsuzu » Mon Mar 09, 2020 7:59 pm

That looks great. Can't wait to see it "in operation".

Jack

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DieselJeep
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby DieselJeep » Mon Mar 30, 2020 10:03 pm

It will be a little while. But I am thrilled it is moving forward.

I ordered a brand new cartridge for the TD04HL-15T through an ohio shop: https://www.xsboostturbochargers.com/

The price was almost exactly the same what an overhaul would be anyways. Also comes with a full year unlimited mile warranty. That way I will have a spare core that doesn't need much but a cleaning, bearings, and balancing. Which I'll can do at leisure.

I still have the inter cooler, piping, oil supply line, coolant lines and fittings, wastegate and misc. odds and ends to buy yet.

But shouldn't be too long.
Unskilled, uneducated, inexperienced, tools/facilities lacking, and faint of heart, be warned:
All vehicles are hunks of crap. Designed by individuals, the majority of which, have never turned a wrench.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby DieselJeep » Wed May 13, 2020 9:39 am

Been a long time coming. Few details left, like turbo to head support brace, and a forklift air filter housing(on floor near fireflite's front wheel) for a more stock look. Tuning and proving yet to do.
But, probably the only operational 4FB1T in the USA.

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Unskilled, uneducated, inexperienced, tools/facilities lacking, and faint of heart, be warned:
All vehicles are hunks of crap. Designed by individuals, the majority of which, have never turned a wrench.
Which one do you want to fall in love with?

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JoeIsuzu
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby JoeIsuzu » Wed May 13, 2020 1:22 pm

We'll definitely need video when this is finished!

Jack

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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby DieselJeep » Sun May 17, 2020 2:57 pm

FINALLY had a chance to turn the fuel up. ONE full turn from my NA setting, with 2 being commonly accepted as a "safe". Being as I am still waiting on my VDO boost gauge, and still have to install my Pyrometer. SO a MINIMAL "safe" experiment.

HOOOOOLY crap. This thing Zips like my 1991 318i!! And not even accelerating as fast as it SHOULD, because it has so much power, it's slipping the clutch at higher RPMS!!

ONE turn. WOW.

Clutch upgrade a MUST. Upgrade on friction material too.

Any suggestions on a shop that can modify a clutch pack?
Unskilled, uneducated, inexperienced, tools/facilities lacking, and faint of heart, be warned:
All vehicles are hunks of crap. Designed by individuals, the majority of which, have never turned a wrench.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby FiatSpider2 » Sat Jun 13, 2020 7:06 am

DieselJeep wrote:Been a long time coming. Few details left, like turbo to head support brace, and a forklift air filter housing(on floor near fireflite's front wheel) for a more stock look. Tuning and proving yet to do.
But, probably the only operational 4FB1T in the USA.


My 4FB1 Turbo is still running fine and has been for over 10 years now as according to the previous owner the turbo has been in there at least that long. Not enough room under the hood to accommodate all the mods you've added but quite adequate for the 2,250 lb Fiat 124 Spider its powering. Once I got the electrical gremlins settled its been a very reliable engine that is well suited to being a daily driver or for intermittent use. Best thing I did for it was put a solar battery charger on it to ensure that even after sitting a while the battery was still fully charged and capable of turning the starter without the starter getting too hot from lower voltage. The 4FB1 likes to eat starters and can't take many starts on a weak/marginal battery.

Another item that can cause issues is the starter solenoid which also engages the starter drive with the flywheel since it takes more amperage to hold against the torque of the starter than the typical starter in gasoline powered engine. I added a dedicated relay to take that load off the OEM circuit designed to hold the load of the lower draw in a gasoline powered vehicle and gave it a 20 amp fused circuit tapped directly to the main battery cable

Having the alternator rebuilt was due to the poor job they did installing the air filter adapter on the turbo so that it was resting on the wiring harness coming out of the top of the alternator which frayed taking out the voltage regulator. After I took care of that and replaced the starter its been starting easily and reliably.

Anyways especially for a rock crawling Jeep be sure that you have the largest rough use battery, a robust power feed to engage the solenoid and the charging capacity to keep the battery in tip top shape as once you push the starter on the 4FB1 it can leave you stranded which will be particularly bad when out in the boondocks.
FiatSpider2 (4FB1 Isuzu Diesel powered 1978 Fiat Spider)

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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby Halden » Sat Jun 13, 2020 8:39 am

FiatSpider2 wrote:Anyways especially for a rock crawling Jeep be sure that you have the largest rough use battery, a robust power feed to engage the solenoid and the charging capacity to keep the battery in tip top shape as once you push the starter on the 4FB1 it can leave you stranded which will be particularly bad when out in the boondocks.


If I remember, the proper sized battery for the diesel imark looks ridiculous under the hood for the size of the car. :lol:

I never had a continuous problem with any of my starters. I did have one go out, but it was just burned at pitted contacts, but the car was 30 years old... Cleaned them up. Cranked like gang busters.

If your in a pinch for starters on this engine you can get by with a starter from a 2.3 or 2.6 gasser. Won't crank as good but will buy you time if your starter is being rebuilt or something... And it'll start given your glow system is in good shape.
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Box Dsl 4x4
82 Short Box Dsl 5 spd
64 Chevy C20 w/ 283 & 4 speed.
05 Sonata with a standard

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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby FiatSpider2 » Sun Jun 14, 2020 7:16 am

Halden wrote:
FiatSpider2 wrote:Anyways especially for a rock crawling Jeep be sure that you have the largest rough use battery, a robust power feed to engage the solenoid and the charging capacity to keep the battery in tip top shape as once you push the starter on the 4FB1 it can leave you stranded which will be particularly bad when out in the boondocks.


If I remember, the proper sized battery for the diesel imark looks ridiculous under the hood for the size of the car. :lol:

I never had a continuous problem with any of my starters. I did have one go out, but it was just burned at pitted contacts, but the car was 30 years old... Cleaned them up. Cranked like gang busters.

If your in a pinch for starters on this engine you can get by with a starter from a 2.3 or 2.6 gasser. Won't crank as good but will buy you time if your starter is being rebuilt or something... And it'll start given your glow system is in good shape.


Remember we are talking about gas vehicles from a different manufacturer that had a 1.8L OHC 4FB1 Turbo transplanted into them. My 124 Spider was set up originally to support a 1kW Marelli or Bosch starter while the 4FB1 uses a Hitachi starter that draws 2kW with a starter solenoid that also draws at least twice the current that a starter from a gasoline powered engine does. When transplanting a diesel into a gasoline powered vehicle these are some of the things you need to consider or you may find out at the worst possible time that the starter circuitry was not really up to the job.

With wiring set up for powering a 1kW starter used to run a 2kW starter and a 3 amp circuit powering a 10 amp solenoid you could up eating starters and solenoids in record time along with going through ignition switches if there is no starter relay being used in that circuit.
FiatSpider2 (4FB1 Isuzu Diesel powered 1978 Fiat Spider)

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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby DieselJeep » Wed Jun 17, 2020 1:40 pm

STILL waiting on my VDO boost gauge I ordered specifically because on quick glance they match the Stewart warner gauges, military switches I got from a Kaiser Jeep M35 cab. Been almost a month from summit? Usually takes 2 days for me. AND fastenal hasn't been shipping. YAY PLAN DEM ICK!!!
But my new Goodyear Wrangler Authority's 31x10.5's showed up. NOW I have to make that spare and gerry can holder!!

I have to put my low time axles in, as mine are REALLY shot. But I have to weld the perches BACK where the factory put them. Someone did an Spring Over Axle mod on them. But still TIGHT and low time. Also getting a double cardan driveshaft. So will be out of commission for a week or two. But ALMOST ready for highway cruising.

Gauges, switches, and on board air are the last engineering fabrication projects(after all that work with axles and suspension) before it is COMPLETE.

THEN ANOTHER full frame off. But very precise, patient, refined resto this time. And modern block urban camo based in metallic paint.
I still want the 16x7 custom willys wheels to happen. But thats bolt on.

Sorry the vid hasn't been posted yet. The vids we took were too big a file. Plus as my first narrative video, I made too many errors.

It'll happen.

Where is YOUR build thread FiatSpyder?? i don't care if it's a used diesel or whaev ya haven't shared it. Still would like to see it.
Unskilled, uneducated, inexperienced, tools/facilities lacking, and faint of heart, be warned:
All vehicles are hunks of crap. Designed by individuals, the majority of which, have never turned a wrench.
Which one do you want to fall in love with?

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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby FiatSpider2 » Fri Jun 19, 2020 11:40 am

DieselJeep - I've been a bit preoccupied by other things and really haven't done much to it to catalogue since its been so reliable once the power requirements of the starter and glow plugs were figured out.

This is one of the few forums that does not allow image uploading so without an image hosting account I am unable to even post an old picture since I do not support cloud or other image/file sharing schemes especially if a fee is required.

You should have been there at OReilly AutoParts when they tried to bench test the 2kW starter from the 4FB1 on their test machine. It blacked out the entire store. They were dumbfounded since that had never happened before. Its a good thing it was early evening and had not passed sunset yet.

When I get around to changing the rear axle ratio and some other things I'll see if I can find a way to post some pics, etc.
FiatSpider2 (4FB1 Isuzu Diesel powered 1978 Fiat Spider)

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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby Halden » Fri Jun 19, 2020 4:18 pm

FiatSpider2 wrote:This is one of the few forums that does not allow image uploading so without an image hosting account I am unable to even post an old picture since I do not support cloud or other image/file sharing schemes especially if a fee is required.


We are strictly against the use of image hosting accounts on here because pictures disappear. Scroll down to attachments and you can attach photos. Message me if you need further assistance
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Box Dsl 4x4
82 Short Box Dsl 5 spd
64 Chevy C20 w/ 283 & 4 speed.
05 Sonata with a standard

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JoeIsuzu
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Postby JoeIsuzu » Sat Jun 20, 2020 10:32 am

Halden wrote:
FiatSpider2 wrote:This is one of the few forums that does not allow image uploading so without an image hosting account I am unable to even post an old picture since I do not support cloud or other image/file sharing schemes especially if a fee is required.


We are strictly against the use of image hosting accounts on here because pictures disappear. Scroll down to attachments and you can attach photos. Message me if you need further assistance
Yes, exactly what Halden said.

Jack