isuzu 4BD1T swap?!

[andrew.fletcher]

Now that my project is actually progressing, next up is the radiator. It's a 4BD2T going into a '72 FJ55. I've got the stock 55 rad and the Isuzu rad (way too tall). Isuzudieselswapper says stock rads are fine regardless of application and I am always leary of all encompassing comments like that. I see a few have stuck with stock and a few have changed out. Since I'm gonna be running a/c there's a little more strain on the engine but not much.

This may be one of those good to do now if you have the extra cash but wait until later because other costs are piling up quick.

[Dougal]

Originally Posted by andrew.fletcher

Now that my project is actually progressing, next up is the radiator. It's a 4BD2T going into a '72 FJ55. I've got the stock 55 rad and the Isuzu rad (way too tall). Isuzudieselswapper says stock rads are fine regardless of application and I am always leary of all encompassing comments like that. I see a few have stuck with stock and a few have changed out. Since I'm gonna be running a/c there's a little more strain on the engine but not much.

This may be one of those good to do now if you have the extra cash but wait until later because other costs are piling up quick.

What Isuzudieselswapper means is that a comparable petrol engine puts far more heat into the coolant. Unless you're pulling out a tiny petrol engine or much smaller diesel engine the stock radiator will be fine.
I'd stick with your original. The Isuzu truck one is sized for pulling 8000kg of truck and load up steep hills in the tropics.

[Dirtgypsy]

any updates on swaps, adapters, etc? looks like this thread just died?

clint

[andrew.fletcher]

Nothing to add as far as progress on my conversion. Right now the focus is getting the 60 axles set under the 55. I did find a good source for Isuzu parts if you're needing them. Real helpful guy and very reasonable prices.

craig floyd
import truck parts
877-554-9008
IMPORT TRUCK PARTS | USED ISUZU TRUCK PARTS | COMMERCIAL | HINO | NISSAN UD | TRUCK PART

[Dirtgypsy]

Hey Andrew,

any chance you could fill me in on why you chose the isuzu over the cummins? As much as I keep looking at the Isuzu as a great alternative I always end up at the Cummins 4bta.

thanks,

clint

[andrew.fletcher]

Partially availability at the time I was looking but mostly noise level. I heard a 4bt running and thought it was pretty loud. Then I took Rhino's 4BD pig out for a drive and was amazed at the noise level difference. While driving I could carry on a conversation in the cab and Rhino's 55 had little to no sound deadening at the time. It really wasn't much louder than my stock '62 was when I had an exhaust leak. I think at the end of the day it's going to cost more because there are more adapters to buy but it's worth it. With the new adapter for a manual transmission it opens up a lot more options for drivetrain also. If you do a noise comparison of your own you'll see what I mean. Pull up next to a bread truck and you'll see how much louder they are in comparison to the box trucks. I think the 4BD is actually quieter in an LC than in the box truck but that might just be me.
Someone will probably correct me on this last part but I believe the 4BD gets a little better mileage than the 4bt. I think around 5 mpg which wasn't a big deal a year ago when I got the engine but since diesel is just shy of $5 by me (4.91 as of today), that's basically a buck a gallon now.

[RHINO]

the stock rad works great to cool the isuzu engine, its actually overkill i think but for the AZ heat i can live with it. plus it was already installed in the rig.

dont know about mileage difference, but i'm averaging 25 so i really dont care

[88tlc]

Sorry for not posting some progress on my project. I have chased around a lot of various small issues to improve performance, and chasing some oil leaks. I will post in the hopes that others can benefit.

1. gauges - I have added a turbo boost gage, and an EGT gage. I think this is a minimum requirement so that you know what is going on with the engine fuel delivery, and boost.

2. oil pan - i had horrendous leaks at the oil pan. I replaced the pan during the rebuild, the original was kinked with a hole. I found in fact that there were supposed to be large plate washers that should have been on the pan. My replacement pan did not have these plates, but the original pan had these plates spot welded on. These plates improved the clamp up alot. I also used an isuzu oil pan gasket that was like 4 mm rubber, that seemed too soft. the new isuzu gasket was a more substantial pressed material, and was awesome. While I had the pan off, I revised the shape to increase clearance to the axle, and moved the drain to the drivers side.

3. turbo to intake - I could hear a small boost leak. a quick fix, but it would help in turbo boost.

4. overdrive and lock up on the 700r4. I had to hook up the electronics to get the lock up to function. I added a later model brake light switch, that also has a cruise shut off. this allows the lock up to turn off if you push on the brake.

See my next post for the driving test! I would welcome any thoughts on the power and performance!

[88tlc]

Driving test ! - I am still not happy with the power. I can not hold the overdrive when going up a hill, and have to go to third gear, and will go about 55mph. it is at altitude about 6000 ft, perhaps a 6% grade. I had HOPED that the 88tlc would cruise up the hill like my Dodge cummins. but I do not have that kind of power, or torque. I would welcome any thoughts on this.

some data first

stock turbo, no waste gate - the turbo will obtain 10 psi boost, but I gotta have my foot in it! at cruise it is perhaps 4 to 5 psi. egt gage is post turbo.

injection pump, and injectors - stock, rebuilt. fuel turned up approx 6 %. Timing was checked at about 12 deg, but this seems to be a course measure per the manual.

700r4 with overdrive. I also have 33s on the rig now. 4.11 stock gears.

at cruise- 65 mph, egt are at 1000 F, boost about 4psi to 5 psi. there is a bit more power there, but the egt are high!

Up a hill - 4% to 6% grade. i have to shift down to third. it has plenty of power but the EGT can climb quickly . boost is 5-7 psi?


what is the EGT temps that this isuzu handle? the small oil jets that shoot into the cylinders, and cool the pistons, post turbo.

would a wastegate turbo give better power, early in the throttle?

[Dougal]

Originally Posted by 88tlc

Driving test ! - I am still not happy with the power. I can not hold the overdrive when going up a hill, and have to go to third gear, and will go about 55mph. it is at altitude about 6000 ft, perhaps a 6% grade. I had HOPED that the 88tlc would cruise up the hill like my Dodge cummins. but I do not have that kind of power, or torque. I would welcome any thoughts on this.

some data first

stock turbo, no waste gate - the turbo will obtain 10 psi boost, but I gotta have my foot in it! at cruise it is perhaps 4 to 5 psi. egt gage is post turbo.

injection pump, and injectors - stock, rebuilt. fuel turned up approx 6 %. Timing was checked at about 12 deg, but this seems to be a course measure per the manual.

700r4 with overdrive. I also have 33s on the rig now. 4.11 stock gears.

at cruise- 65 mph, egt are at 1000 F, boost about 4psi to 5 psi. there is a bit more power there, but the egt are high!

Up a hill - 4% to 6% grade. i have to shift down to third. it has plenty of power but the EGT can climb quickly . boost is 5-7 psi?


what is the EGT temps that this isuzu handle? the small oil jets that shoot into the cylinders, and cool the pistons, post turbo.

would a wastegate turbo give better power, early in the throttle?

You need to shift your EGT probe to before the turbo. Which fuel pump do you have? Some have boost compensators, some do not. If you have a sick boost compensator then you'll be way down on power.

I've run my engine at up to 750 deg C preturbo regularly for a long time with no issues. These engines are built to work hard all day, factory fitted oil spray, oil coolers etc.

What rpm do you think you have at 65mph?

A smaller wastegated turbo will give more boost, but I'm not convinced boost is the only issue you have right now.

[gifu]

high EGT's... low power... hmmm... my first thought would be to check and recheck timing.

[RHINO]

i dont know why you think your gonna go up a hill with a 3.9 like your 5.9 dodge does. also the high egt's could be the result of timing issues, or it could just be that you turned up the fuel.

while i am completely satisfied with the power and drivability of mine i will be doing some tuning in the future, these turbos are very modest with boost so i'll prolly add some boost before i turn up the fuel or anything else. looking at wastegated turbo's so i can get more boost faster.

[88tlc]

Originally Posted by Dougal

You need to shift your EGT probe to before the turbo. Which fuel pump do you have? Some have boost compensators, some do not. If you have a sick boost compensator then you'll be way down on power.

I've run my engine at up to 750 deg C preturbo regularly for a long time with no issues. These engines are built to work hard all day, factory fitted oil spray, oil coolers etc.

What rpm do you think you have at 65mph?

A smaller wastegated turbo will give more boost, but I'm not convinced boost is the only issue you have right now.

dougal and company, thanks for the comments. you are right, that the 3.9 should not perform like a 5.9! the trucks are about the same weight empty, i do expect to have that same torquie power though.

egt to preturbo - that means removing the turbo? I guess i should just rebuild it then while I have it off, seems like the only thing not rebuilt on the motor. Preturbo is more accurate temp reading?

fuel pump - I have a inline low pressure mallory I added back near the tank, and the lift pump on the IP.

boost compensator? - is that the aneroid, altitude compensator? besides this on the back of the IP, there is nothing else.

Timing - is there a more accurate way to get the 13 deg BTDC on the IP? I take #1 line off, and turn the engine over, see the fuel rise in the delivery valve. i would guess this is accurate to within a few degrees only.

egt temps - wow - that is like 1700 deg F. It does feel like the engine is just getting into its game, getting power, getting boost, when I am having to back off of a 1050 to 1100 egt. would be great to let er bark to like 1300 or 1400 F, but I am obviously concerned about melting something down!

rpms - I have yet to truly calibrate this tach, I can only estimate from a idle and governed rpm. with the over drive on the rpm is running approx 1500 to 1700. I do think this will work great on the open flats, great gas mileage. but it does feel geared high, especially with the 33 tires on there.

a quick movie of the engine running after rebuilding the IP.

YouTube - 1988 fj62 landcruiser with isuzu diesel engine

[dieselcruiserhead]

If it helps I had the same fears of wanting a secondary electric pump when I put my Cummins in (not trusting / not wanting to trust the mechanical lift pump) and it actually did more damage than good, the engine ran a little weak (for what its worth!)... When I removed it, it was great. Not sure if that helps or not.

Second thought, the boost is way low... I don't think anything 'wrong' with it, just the way it is designed. But it is a direct inject engine, 10 psi is way way low, you can probably do 25-30 if you wanted to but about 15-20 psi is healthiest and most efficient and is a night and day difference (stock 4BTs are about 12psi max non wastegasted. Replacing the turbo really wakes up the engine, as if it had been slumbering its whole life, no loss in efficiency at all, in fact possibly increased. Just the way they did the logic around turbos back then. Mostly worried about higher EGTs from towing etc - which turbo out were bunk fears anyway). You could do a 4BD-2T turbo if it will work. But my advice is use something like a Cummins turbo if you can fit it, cheaper, just as if not more reliable, metric fittings, etc... Bill I'll pull out my HY-35 - it is massive, but smooth breathing and free flowing, works great in 3.9L diesel applications, wastegated, powerful.. But not sure if you want to get this "custom" as we;d have to make an adapter plate. But more turbo is absolutely awesome Wastegated is nice but not necessary either, all it is is a blowoff, drops your high RPM boost from 20-25 to 15-20 depending on what you have it set at. So the turbo you choose does not necessarily have to be wastegated

[Dougal]

Originally Posted by 88tlc

dougal and company, thanks for the comments. you are right, that the 3.9 should not perform like a 5.9! the trucks are about the same weight empty, i do expect to have that same torquie power though.

egt to preturbo - that means removing the turbo? I guess i should just rebuild it then while I have it off, seems like the only thing not rebuilt on the motor. Preturbo is more accurate temp reading?

fuel pump - I have a inline low pressure mallory I added back near the tank, and the lift pump on the IP.

boost compensator? - is that the aneroid, altitude compensator? besides this on the back of the IP, there is nothing else.

Timing - is there a more accurate way to get the 13 deg BTDC on the IP? I take #1 line off, and turn the engine over, see the fuel rise in the delivery valve. i would guess this is accurate to within a few degrees only.

egt temps - wow - that is like 1700 deg F. It does feel like the engine is just getting into its game, getting power, getting boost, when I am having to back off of a 1050 to 1100 egt. would be great to let er bark to like 1300 or 1400 F, but I am obviously concerned about melting something down!

rpms - I have yet to truly calibrate this tach, I can only estimate from a idle and governed rpm. with the over drive on the rpm is running approx 1500 to 1700. I do think this will work great on the open flats, great gas mileage. but it does feel geared high, especially with the 33 tires on there.

a quick movie of the engine running after rebuilding the IP.

YouTube - 1988 fj62 landcruiser with isuzu diesel engine

Yes the EGT probe before the turbo gives a more accurate reading, the turbo causes a temperature drop which depends on the temperature it's running at, it's efficiency and the boost it's currently putting out.
Some people use a fudge factor of 100-300 deg to compensate for the probe being after the turbo, but it's not a good idea.

I have no external lift pump, the mechanical lift pump (with the hand primer pump attached) gives all the pumping your engine needs.

Some engines have an altitude compensator (FSM calls this an aneroid) which is a round device with no lines attached. The boost compensator fitted to some engines is cast aluminium and screwed together with a pressure line to the inlet piping.
Some engines have both, some have none. My engine has the boost compensator only.

Listening to your video, your engine sounds more advanced than mine currently is. I've been experimenting with the timing a little over the last few months by incremental adjustments.
Too far advanced can make the engine fall off boost, it would lead to situations where EGT's would keep rising but not produce boost and cause me to back off to save the engine. Knocking the timing back a little (rotate top of the pump away from the block) brings on boost sooner.
The interesting part, I've found no noticeable difference in fuel economy going from far advanced and right back to what I think is slightly retarded from the factory setting. I haven't confirmed my timing by any method like the one above.
You'll notice the difference in idle sound that a relatively small change in timing makes.

1500-1700 is not a speed you'll be climbing hills at 65mph with. In stock form this engine will only be putting out around 52kw (70hp) at 1500 rpm.
The stock turbo may also not be producing enough boost there.

Regarding turbos.
I have a turbo like yours in my parts bin, but I haven't installed it as I'd need to redo all my plumbing (exh, intake, oil lines etc). The exhaust A/R on it is significantly bigger than the wastegated T25 turbo I'm currently running, but the compressor is identical. With increased fuel I get 20psi boost by 1500rpm.
Carcrafter on 4btswaps.com has fitted a holset to his 4BD1T, I don't think he's got any driving reports yet.

[rtarh2o]

He is turning about 2000 rpm at 65. I have the same 700r4, 4.11's and 33" tires. I have a tiny tach installed and 1800 rpm is about 60 mph, seems like I am turning about 2030 at about 67 mph with my 6.2 diesel.
Hope you get the power thing worked out, I really think that could be a great engine, seems like a 3.9 with turbo should be more than enough. I am sure my 6.2 would be in 3rd gear going up a grade at 6,000 ft as well.
Good luck
Rusty

[astr]

Originally Posted by Dougal

...Some engines have an altitude compensator (FSM calls this an aneroid) which is a round device with no lines attached...

On my 4BD2T, Isuzu uses a clever trick to reduce fueling when the engine coolant temp gets too high. They apply a regulated vacuum from the vacuum pump to the altitude compensator to make the IP think that it is at a higher altitude and therefore reduce fueling. Therefore, the port on the altitude compensator does have a line connected from it to an electrically-controlled valve. The 4BD2T also has a boost aneroid. None of my 4BD1T's have a hose connected to the altitude compensator nor do they have a boost aneroid.

[zaksl17]

Hello, i've been driving around my 4bd1t powered fj40 for about a month now and finally got to putting in my front drive shaft. i have about 1 1/2" to 2 " between the front drive flange at the pumpkin and the oil pan. well its not enough because it hit, now i have a big dent in the pan.

I saw that 88tlc did some work to his pan. I was wondering how much room is in the right front corner of the sump. is the oil pump or pick up near there? 88tlc how much did you find a new (or used ) oil pan for? My 40 is now my daily driver so i was thinking about getting a used pan to modify.

any advice would help thanks?

[Dougal]

Originally Posted by zaksl17

Hello, i've been driving around my 4bd1t powered fj40 for about a month now and finally got to putting in my front drive shaft. i have about 1 1/2" to 2 " between the front drive flange at the pumpkin and the oil pan. well its not enough because it hit, now i have a big dent in the pan.

I saw that 88tlc did some work to his pan. I was wondering how much room is in the right front corner of the sump. is the oil pump or pick up near there? 88tlc how much did you find a new (or used ) oil pan for? My 40 is now my daily driver so i was thinking about getting a used pan to modify.

any advice would help thanks?

The oil pump is quite a way back. On the turbo side of the motor you'll see a cover plate with two bolts just above the starter, that's the drive for the oil pump.

The front of the sump is pretty much clear for modification, but you need to pull it off to check anyway.
I'll have mine apart shortly to change the thrust bearings (forgot to order them last rebuild).

[astr]

Originally Posted by Dougal

The oil pump is quite a way back. On the turbo side of the motor you'll see a cover plate with two bolts just above the starter, that's the drive for the oil pump.

The front of the sump is pretty much clear for modification, but you need to pull it off to check anyway.
I'll have mine apart shortly to change the thrust bearings (forgot to order them last rebuild).

Pictures of a 4BD1T oil pan:

[andrew.fletcher]

Go to post number 694 for the link for parts. I got a 1T pan for around $60 I think plus shipping.

[andrew.fletcher]

Looking for a part number for the bushing that goes in the end of the crankshaft for installing the Isuzudieselswapper adapter???

[ozwallaby]

Astr, is that an oil return on the sump.. where from.?