Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

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

Post by DieselJeep »

Hey everyone,
Wanted to share some pics that have been a long time coming. Been slow sorting though two motors worth of bolts hardware and parts(thanks old roomie!!).

And finding all the weird replacement parts and cup plugs that are so rare in America. JEEZ!

Hope no one is offended by my mods/color choice/custom valve cover. Few details left, timing cover still needs to be painted yellow, but ya get the idea. Still blown away to see that isuzu bell housing 10+ years newer than the motor slide right on the back of the 4FB1 and bolt up to that jeep trans.

Still can't express enough gratitude to Jerry Lamond for sharing his knowledge, expertise, and Isuzu parts stockpile with me. You are THE MAN, Sir!

Enjoy!
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Unskilled, uneducated, inexperienced, tools/facilities lacking, and faint of heart, be warned:
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DieselJeep
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

What you can't see:
All bearings and seals replaced in entire motor. Few new valves.
Head, intake and exhaust manifolds gasket matched and mildly ported, and bowl blended under valve seats. Just couldn't swallow the core shift, esp. in the exhaust manifold.

Huge kicker bonus worth the massive work:
ANY and ALL rust found was etched with muratic acid. ALL bolts and hardware, flexplate, cast iron brackets, coolant tubes, everything. :shock:

Exhaust manifold, after porting was etched, and painted inside/out with Ceramic VHT paint.

Anything painted "cat yellow" has self etching primer as base. Black is epoxy paint.

There is near ZERO rust to be found anywhere on this 30 year old motor.

That's how I roll, yo! :mrgreen:

For the first time in my life, I built something to be SLOW and Loud! hahaha

Thoughts, questions, opinions, advice welcome...
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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JoeIsuzu
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Isuzu vehicle(s): Original owner, '83 LS Diesel, 5-spd, 2wd, Long Bed, restoration in progress!

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

Post by JoeIsuzu »

That looks REALLY good!

Jack
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Halden
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Isuzu vehicle(s): 83 Dsl LS Long Bed 4x4, 82 Dsl 2wd Short Bed 5 spd

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

Post by Halden »

Wow! if only I could get my 4fb1's looking like that! I'd love to do that, but then again I am a total cheapskate with them! Looks awesome!
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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nucleus
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by nucleus »

Nicely done! Love the CAT Yellow!
1991 4X4 Pickup powered by a Gen 3 Trooper Turbo Diesel engine built by Jerry Lemond. 5 Speed Trooper MSG tranny behind the engine.
Gerald K4NHN
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by Gerald K4NHN »

Great work and a lot of effort also.
Gerald K4NHN
Cayce, SC

"One test is worth a thousand opinions"

1983 LS DIESEL LONG BED 2 W/D 126K miles

1986 LS Trooper Tubro Diesel 4 W/D 186K + miles SOLD
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Halden
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by Halden »

Where did you get the intake and exhaust manifold gaskets?
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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arrowmntdiesel
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by arrowmntdiesel »

Yes, for sure that looks great!

As far as the color and the re-badge....Cat should be so proud to have the heart of an Isuzu Diesel.

The polishing truely does look good and it is refreshing to see such effort and time put into a project to make it one's own.

Nice Job!

Mark
AAS degree Diesel Technology 2014, 15 yrs Isuzu Pup diesels. Owner: Arrow-Mountain Diesel services & Arrow-Mnt Windows, Medford, OR. Love God! One Marriage-One Wife, 2 awesome young ladies as my kids. Happily Married for 30+ years. One Blessed Man!
lserd.oldrp
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by lserd.oldrp »

Yes, that looks great love that cat yellow, black and polish job.
Great to see such effort put in to the performance gain of porting and match alignment.
Nice job!
1984 Isuzu pup N/A 2.2 Diesel 5 speed 3.42 gear Short bed.
Up grade's gt2052 turbo, 86-87 volvo inter cooler, 4'' cold air intake, 3'' Exh. aero diesel turbine muffler.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by mike71800b »

DieselJeep, man that thing looks super in yellow. I gotta say i like that even better than the cummins beige i used on my c223 :)
86 Trooper TD
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nucleus
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by nucleus »

Incidentally, what did that valve cover come off of originally?
1991 4X4 Pickup powered by a Gen 3 Trooper Turbo Diesel engine built by Jerry Lemond. 5 Speed Trooper MSG tranny behind the engine.
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

Thank you everyone for the kind words.
Has been a LOT of effort, but I feel it will be worth it when 5 years from now I can still hose the motor off and see no rust, or during the next overhaul.

The gaskets are still available, but you have to look. I am lucky I found everything I did. ALL of it is getting very, VERY hard to find, and there was a lot of things I couldn't find that I wanted to replace, but time and budget are getting thin for drive train. Still have the rest of a Jeep to put together. I am certain there is much more cross reference in things like valves and bearings I need to discover, but timing plate to block, or oil filter adapter gaskets? You most likely won't find them anywhere, especially if you are actually looking for/needing them.

Yes. I completely removed the timing plate as well. Wonder when the last time THAT was done on a 4FB1? lol SO glad I did. There was coolant seepage everywhere, the bolts were a BEAR to get out, MOST of them. I had to weld a nut onto one of the countersunk plate locating bolts to get it out. Very very thin layer of Permatex ultra grey on the gaskets and other strategic locations should cure that. Glad I did though. My short block should be fine for 20+ years, hundreds of thousands of miles.

I have a PDF scanned from JLemond's last 4FB1 timing plate gasket from his stock. If you print the file at 100%, it should be usable as a template.

SO I recommend everyone else who has a 4FB1 abandon the motor, sell me your serviceable parts, and not to buy any new parts for a 4FB1 for say another five years. :lol:

Either that, or a few people that actually have a REAL interest in keeping this motor alive in America for decades to come, not simply running them into the ground with no concern or regard might want to help each other find parts sources. LOT of stock things NLA. I got NOS cam bearings from a shelf in TURKEY. I have another set sourced in AUSTRALIA that a good mate is picking up for a decent price. After that? Only complete set I found was almost $200 shipped.

These are all things ANYONE and EVERYONE with a 4FB1 SHOULD be thinking about if you value these awesome lil diesel motors. Not AFTER your crap blows up from neglect. Because you probably won't find what you need in an emergency.

The valve cover is a stock Isuzu 4FB1 cover that I modified/customized. I cut off the 2 fins that were located where the modified Caterpillar 3406 aluminum badge is now, with a carbide in a dremel. Some covers have "Isuzu" cast there.
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

Post by DieselJeep »

Hey guys,
I ask any people who have had real life experience boosting the 4FB1 to please share real world numbers please?
Turbo used, source, price paid? Perhaps verified boost @ RPM's, A/R, Inducer size.

Whatever you might know, have learned, and the science of why how when etc if known.

IHI RHB5 VJ11 seeems like a cheap to obtain and service, common, and close place to start to me, but I could be wrong.
If I understand what I have read and been told about what I am trying to do, I want to create slight boost at cruise, say @ 2psi.
If I am reading the torque curve of the 4fb1 NA dyno graph I found, that SHOULD be @ 2,000 RPM.

Which seems about PERFECT if I am reading this right?

http://www.angelfire.com/extreme4/mattmouth182_rag/mx6/page.html

Ronbros or ?

Thanks again, Gents! Couldn't have done it without all the input and sage advice! :mrgreen:

ESPECIALLY Jerry!
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

Post by DieselJeep »

So, in the midst of having IP issues,

I found a very low mileage, saab sourced, Garrett TB2531 "60" trim, .48/.49 AR's, absurd cheap on CL. TINY lil thing. But, ball bearing, full floating center, water cooled, and did I mention TINY? Capable of supposedly supporting near 200HP, but I don't think I will be stressing the unit at all. The inlet on the turbine side isn't even a full T25 style rectangle. It's a circle about @ 2" or less.

It came with a LOT of aluminum tubing, silicon elbows, etc. The saab intercooler if mounted correctly, might help catch oil and avoid run-on in the event of a turbo seal leak, as both the inlet and outlet are on one side of a narrow unit.

If I understand all the principals, this map illustrates that I should be 70% turbo efficiency at 14.7 psi boost @ 190 CFM @ 4,000 rpm.
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Unskilled, uneducated, inexperienced, tools/facilities lacking, and faint of heart, be warned:
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DieselJeep
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Re: Isuzu 4FB1 overhaul/resto-mod for CJ5 conversion

Post by DieselJeep »

What a cute lil' turbo!
Believe it or not, this tiny thing is supposedly capable of nearly 200HP on a gas motor. Hard to believe, as small as the turbine inlet is.

My two goals are @ 2-3psi boost at cruise, somewhere between 1,500RPM and 2,000RPM. The lower the better, as long as it is above say 1,250. This will coincide perfectly with the dyno proven torque curve of the N/A 4FB1 cam here in the US, and increase efficiency at cruise.

Plus, get the 4FB1 back up to @ 100-120hp, where it was designed to be. That tiny turbine inlet should be freakin PERFECT for low RPM boost!

I plan to never really wind the motor beyond 4,000RPM(like a "normal diesel"), and hope that I am getting 15psi OR LESS at that point. I know the factory governed redline is the highest I have heard of for a factory diesel, at a screaming 5,400 according to J Lemond. I have no need for that. I might do it occasionally to blow out the cobwebs, but very, very rarely. Depends on where real life testing shows <15psi.

A factory IDI diesel will NEVER make big power without huge mods. EVER. The combustion flame is deflected from the piston crown, so power is lost. The head restricts the flame front. Top end power is not even much of a consideration for me. IMHO, huge boost in an IDI diesel is simply a way to wear out/blow up your motor sooner.

I just want to fill my 15 gal tank for <$15, get @ 30mpg, and have enough power to operate it safely. Think I might just do that. I have a bad habit of reading books, doing all the complex arithmetic, and keeping magazines and internet gleaned "info" to a distant, subjective suspicion.
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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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