high EGT's... low power... hmmm... my first thought would be to check and recheck timing.
isuzu 4BD1T swap?! (1 Viewer)
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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.
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.
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isuzu 4bd1T - how much power to expect
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
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
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
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
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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.
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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
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
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.
oil pan clearence
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?
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).
Go to post number 694 for the link for parts. I got a 1T pan for around $60 I think plus shipping.
Need part number for bushing of Isuzudieselswapper
Looking for a part number for the bushing that goes in the end of the crankshaft for installing the Isuzudieselswapper adapter???
Looking for a part number for the bushing that goes in the end of the crankshaft for installing the Isuzudieselswapper adapter???
Astr, is that an oil return on the sump.. where from.?
Motor mounts
Have some people used the stock 4bd mounts? Any feedback?
I have finally finished my bottom end rebuild, clean, paint, refurbish on my 4bd1t and am waiting on adapters and prepping the 80: grind off old mounts and drop the fuel tank to work on that. I am going pretty slow as life tends to intervene frequently. My build cost increased due to the weak dollar: my trans adapter is from Marks and the OME lift is from OZ land as well
.
Have some people used the stock 4bd mounts? Any feedback?
I have finally finished my bottom end rebuild, clean, paint, refurbish on my 4bd1t and am waiting on adapters and prepping the 80: grind off old mounts and drop the fuel tank to work on that. I am going pretty slow as life tends to intervene frequently. My build cost increased due to the weak dollar: my trans adapter is from Marks and the OME lift is from OZ land as well
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That little tube connection on the right rear corner of the oil pan is a return from the air/oil separator. A vent pipe from the valve cover goes to a cylindrical (4" x 2" dia.) air/oil separator that, I assume, has some sort of internal baffles. There are two tubes coming from the bottom of the separator - one vents to the atmosphere and the other goes to the oil return on the pan.
I didn't add the second bung - it came that way from Isuzu. I believe an optional oil heater screwed in there. Both my 4BD1Ts have the bung.
yup little tube is air/oil seperater. its not really baffled its a wire mesh, the oil falls out of the air as it runs through and collects in the container,, then when it reaches the right level it runs down the tube and into the pan.
i have the bung also and i think astr is right, optional cooler or something, its made to carry some weight.
i use the isuzu motor mounts,,, they are soft and the engine moves alot. but they work well and isolate the engine from the rig.
there is no bushing for the crankshaft with dieselswappers kit,,, if you had an auto you are set, if you had a manual then you remove the pilot bushing thats in there.
i have the bung also and i think astr is right, optional cooler or something, its made to carry some weight.
i use the isuzu motor mounts,,, they are soft and the engine moves alot. but they work well and isolate the engine from the rig.
there is no bushing for the crankshaft with dieselswappers kit,,, if you had an auto you are set, if you had a manual then you remove the pilot bushing thats in there.
yup little tube is air/oil seperater return line. as oil falls out of the air in the container it internally overflows and runs into the oilpan.
i have the bung also and i think astr is right, optional cooler or something, its made to carry some weight.
i use the isuzu motor mounts,,, they are soft and the engine moves alot. but they work well and isolate the engine from the rig.
there is no bushing for the crankshaft with dieselswappers kit,,, if you had an auto you are set, if you had a manual then you remove the pilot bushing thats in there.
i have the bung also and i think astr is right, optional cooler or something, its made to carry some weight.
i use the isuzu motor mounts,,, they are soft and the engine moves alot. but they work well and isolate the engine from the rig.
there is no bushing for the crankshaft with dieselswappers kit,,, if you had an auto you are set, if you had a manual then you remove the pilot bushing thats in there.
