Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

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

Post by OzarkDaredevil »

Extreme coolness
Tom
'81 4x4 diesel LUV - daily driver
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Halden
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by Halden »

Very cool. These little guys will scream at 5000 RPM all day. Glad to hear it moves under its own power! A turbo will pep that thing right up
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Box Dsl 4x4
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

Whoever mentioned in the past that it would do OK on the road was right, it does on flatter road @ street speeds.
But it does really need that turbo, and a tach. I am going no where near an actual highway until it's turbo'd.

SOOO much work done, and SOOO much left to do. :roll:

If it were easy and/or cheap, everyone would have an old or custom vehicle, right?

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

Post by DieselJeep »

Going to pick up a C223T IP later this week, possibly Saturday. Pretty excited about that.
Still waiting on the new primer/filter base, and clear poly fuel line.

So in the mean time, a side note:
Been getting cold, esp. last week, and the fiberglass top I have needed a LOT of 'glasswork to install. Been dreading it, actually.
And rather disliked the Wrangler appearance of it, being as the build is military themed(eventually).

I happened to find a uber rare gem for uber cheap.
An early-mid 60's Kelly "Safari" "Full Cab" Cj5 hardtop, doors and windshield on a '68 or older CJ6 at the local pick yer part for <$140!
So rare, hard to find much info about it. Needs a total resto. All glass is there, in decent shape. Side glass still rolls down. Little bit of "cancer", but very easy to repair. And all rubber seals are dried out and thin from years of compression, so makes quite a loud rattly din, esp. at idle.

Often said in Jeep circles to be the most military looking CJ hardtop ever made. And if the CJ felt military before, now ya can't help but feel like ya are driving a tank in a convoy. Roomie's brother even said it looks like a tank. The 45* bevels on the doors really make it look like armored glass.

And took me all of a few hours total to have a roof!

One and only downside: Thick metal, very well designed and built, lotta thick safety glass. Doors alone weigh @ 40lbs. apiece. Probably added near 200 lbs = even slower Jeep. :roll: But soo worth the added penalty.

What do ya think, folks?

DSCN2840.JPG
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OzarkDaredevil
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by OzarkDaredevil »

I really like it and I'm not usually a Jeep guy. Well done!
Tom
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

]Brake problem where drums are getting HOT recently, and has me stumped. So I have to post this here for reference for a Jeep site. Can't upload there for some dumb reason.

Sorry everyone

DSCN2842[1].JPG
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mike71800b
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by mike71800b »

Been through this before on a scout, the brake push rod was too far forwards for that particular master cylinder.
If the mastercylinder piston doesn't retract fully fluid doesn't return to the mastercylinder.
Here are a few other considerations as well since i don't know if you have drum or disk up front.
http://www.jeepforum.com/forum/f8/1978- ... up-998353/
86 Trooper TD
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

Got it sorted.
My theory as the slaves were just fine while cool, they must have been absorbing heat from the drums, but slightly sticky from sitting a good while.
More and more heat builds, seizing them up tighter and tighter.

New slaves solved it.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

I have been tinkering on the jeep last 2 days.
I welded a new bracket to mount the new Racor/Parker primer/fuel filter/water separator. The mounting bolts were wider than the original Isuzu filter boss mounting holes. Also welded a support below the original, so more of the larger Racor mounting boss had purchase and support. The filter assembly vibrates much, much less now at idle.
I also modified the primer/filter assembly(do NOT try this at home, kids!) so I could use a commonly available, and MUCH less expensive, Ford and International fuel filter. The Parker style filter housings, and aftermarket filters, were very expensive, and not locally available in stock. Now I can buy a new fuel filter at any semi or auto parts store, in stock, for a REASONABLE price! :mrgreen:
I removed the black fuel supply hose in the engine compartment and replaced it with clear blue polyurethane hose, so air bubbles can be easily seen. It cured the fuel problem, no air bubbles, and it makes a lil more power! Some tuning to do yet, but FINALLY can be done now that fueling it as it should be.
Side note: Do NOT use the "fuel injection" style clamps(I bought these at Advance). Even doubled and clocked 180*, they suck air! This one is here temporarily, as I had to heat the hose to get them on the barb fittings anyways, and are so tight as to have to be cut for removal.
DSCN2846.JPG

I also mounted my 3/8" thick, 2x4 "C" channel bumper/winch mount and tow hooks. I also sanded and painted the top black.
Also discovered a large part of my starting problems were caused by the momentary push button switch I used to heat the glow plugs. Replaced it with a high amp toggle, with red warning light wired to the GP buss bar. This will let me know that there are no shorts or bad connections in the GP system. And remind me not to blow out my glow plugs.
Very very productive weekend, making the jeep much more reliable, serviceable, and a little prettier.
DSCN2845.JPG

Just in time! Yes, it's getting cold, and that is melting frost on her!
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

I finally installed a fuel gauge a few days ago.
It was getting annoying to try and put $10 of fuel in once a week, and topping it off @ $5.
Been over 2 weeks and I haven't put fuel in it, reading slightly under 3/4, of a 15 gal tank.
I have only burned @ 3-4 gal.
That's all my driving, and probably @ 30mpg city driving, exclusively.
What an awesome motor the 4FB1 is.

Can't wait to see what it will be like as designed originally, a lil better with a modern design @ perfectly sized turbo.
And then a modded C223T IP.

And won't be winding the snot out of it like I am now.
Well, at least less, haha.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by poprivetj1 »

I really like it! I miss my 89 Isuzu truck with the 4FB1. I wanted to turbo it as well. Great build! can't wait to see the refinements such as the turbo.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

I put my my first batch of "alternative" fuel in the Heep. Mostly used ATF, some used Rotella oil, mixed @ 50% of Diesel. Heep LOVED it. NOTICEABLE power gain, and have less than $10 in @ 10 GAL, 3/4 tank, which will be @ 300+ miles of driving.

Smells like a coal fired steam locomotive.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by Halden »

DieselJeep wrote:I put my my first batch of "alternative" fuel in the Heep. Mostly used ATF, some used Rotella oil, mixed @ 50% of Diesel. Heep LOVED it. NOTICEABLE power gain, and have less than $10 in @ 10 GAL, 3/4 tank, which will be @ 300+ miles of driving.

Smells like a coal fired steam locomotive.



I imagine you've looked into it. But from what I've read diesel oil contains zinc which to my knowledge can foul your injectors and new ATF has friction modifiers for clutch packs which can wear things down in your pump. If you've got some articles I'd definitely love to add them to my studies thread of they're actually articles/papers.
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

Post by DieselJeep »

I have.
And everything was cut about 50% with diesel. It also won't be an everyday thing.

Unless for some reason we can't get fuel at pumps. :wink:
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

I have to do WAAAY too much cranking, repeatedly, to get it started when I have no access to 120V for the preheater. I don't like how much cranking it takes at all. I can't just run down to the parts store and pick up the CORRECT starter, so I can't live with this. Plus, a 50+ year diesel/trucking veteran buddy gives me crap about it too. Can't be smearing the Isuzu name like this in the industry.

Starts right up when engine is 140*+. So I want to install the C223T pump N/A with the functioning(hopefully) CSD in hopes to cure this, and begin dialing timing and fueling in as the turbo install is only a few weeks away now. It had clean green diesel still inside, if not slightly sour smelling. Hoping all is fine to use as is for now.

I guess I do need help with proper line routing for this C223T pump. I realized there are two @ 1/8" fuel lines up by the boost anneroid (not the boost pressure port, but very near it) on the "case pressure regulator valve" or whatev it's called). They are that I am uncertain how they should be routed to be sure the CSD works properly, and the IP case sees correct pressure for timing. I am assuming that one is from the @ 1/8" injector return line, then routed to back towards the fuel tank? Or are both only returns? If so, could I run both into say 5/16 return line and cause no timing/excessive IP case pressure issues? Should the injector return/bypass be routed separately all the way to the fuel tank? Or plumbed into one of the stubs on the IP?

Alas, zero results on Google or anywhere...

There is the main fuel inlet(no prob), Boost sensing port, and the two lines I am speaking of on the case pressure regulating valve thingy. And then of course the @1/8" injector bypass/return which is routed back to the tank by it's own line for now.

Like my terminology? haha

Uh Oh.
Look what I have. Was going to swap this today, until I realized I haven't any idea how to do the returns correctly.

DSCN2889[1].JPG
Unskilled, uneducated, inexperienced, tools/facilities lacking, and faint of heart, be warned:
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