Great presentation. I have one of these and will be following closely.
Isuzu 4BD1T Lexus LX450 (Land Cruiser) Build
4
So this thread is going to follow the swap of a 4BD1T into an 80 series Land Cruiser (Lexus LX450 in my case).
Truck: The Toyota Land Cruiser/LX450 is in my case a 1997, I got it 3 years ago from a young lady that had owned it for 10 years and driven it into the ground. I spent 5 months going over every system of the truck and rebuilding most of it from engine to axles. The truck comes standard with a 4.5L I6 DOHC engine producing 214hp and 265ft/lbs, although it has good power its offset by the regular 8-10mpg fill ups. My truck came with the factory diff lockers and 4.10 gears. The truck has proved to be extremely reliable and has taken us on some great trips so far.
As she sits now:
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Engine: I had got this truck planning on doing a diesel swap, once I got it I started researching all sorts of options from Cummins to Toyota 1HD-t’s. I ruled out the Cummins as I worked at a Cummins performance shop and had done a few 3000mile road trips in them. Great power but just a too noisy for me. The Toyota 1HD-T was the obvious choice but given there extremely high cost for an engine and trans ($9k) I had to give that up that as well. I had read threads on Mud by Doug720, Longbow and one other that did a Mitsu 4B34? swap. That got me looking at the 3.9L 4cyl Diesels both Isuzu and Mitsubishi, I liked that the Mitsubishi as it kept the exhaust and intake on the same sides as the stock engine. In the end Longbows thread on a simple adapter to the older A440F trans (stock in the 91-92 80 series) got me into the 4BD and specifically the 4BD1T. As well as the simplicity of the 4BD with its fully mechanical injection system. After lots of research on the 4BD I knew it was the way I wanted to go. I was looking for a 4BD1T for about 5 months on and off, found a few trucks in the $2000 range. I then got a PM on Mud with someone selling a 4BD1T with no history or other information. It was Proffit cruisers clearing out there inventory. I got the 4BD1T one week after buying it and to my surprise it looked to be in very good shape.
Unloading:
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Data plate:
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First run:
Transmission: After deciding that the 4BD1T was the engine I wanted I got on the hunt for a 91-92 80 Series A440F with the AWD t case. I wanted to go with this transmission as it’s an all hydraulic controlled trans mission so I does not need any ECU or wires connected to operate. After a short hunt I found what I needed in LA, it was an A440F with t case and converter for $100 with 200k miles on it and out of a truck that was driving before it was parted. I got the transmission shipped up for $100 by a cruiser guy headed home from LA for the holidays. The guy I got the trans from was good enough to ship my converter off to Road Runner converters in Phoenix AZ for a full rebuild and stall down to 1600 RPM. Thanks to Longbow (Don) for their information and all the information and help along the way.
So that gets me to about present with my journey. The following pages and posts will follow my swap and its components.
Truck: The Toyota Land Cruiser/LX450 is in my case a 1997, I got it 3 years ago from a young lady that had owned it for 10 years and driven it into the ground. I spent 5 months going over every system of the truck and rebuilding most of it from engine to axles. The truck comes standard with a 4.5L I6 DOHC engine producing 214hp and 265ft/lbs, although it has good power its offset by the regular 8-10mpg fill ups. My truck came with the factory diff lockers and 4.10 gears. The truck has proved to be extremely reliable and has taken us on some great trips so far.
As she sits now:
Engine: I had got this truck planning on doing a diesel swap, once I got it I started researching all sorts of options from Cummins to Toyota 1HD-t’s. I ruled out the Cummins as I worked at a Cummins performance shop and had done a few 3000mile road trips in them. Great power but just a too noisy for me. The Toyota 1HD-T was the obvious choice but given there extremely high cost for an engine and trans ($9k) I had to give that up that as well. I had read threads on Mud by Doug720, Longbow and one other that did a Mitsu 4B34? swap. That got me looking at the 3.9L 4cyl Diesels both Isuzu and Mitsubishi, I liked that the Mitsubishi as it kept the exhaust and intake on the same sides as the stock engine. In the end Longbows thread on a simple adapter to the older A440F trans (stock in the 91-92 80 series) got me into the 4BD and specifically the 4BD1T. As well as the simplicity of the 4BD with its fully mechanical injection system. After lots of research on the 4BD I knew it was the way I wanted to go. I was looking for a 4BD1T for about 5 months on and off, found a few trucks in the $2000 range. I then got a PM on Mud with someone selling a 4BD1T with no history or other information. It was Proffit cruisers clearing out there inventory. I got the 4BD1T one week after buying it and to my surprise it looked to be in very good shape.
Unloading:
Data plate:
First run:
Transmission: After deciding that the 4BD1T was the engine I wanted I got on the hunt for a 91-92 80 Series A440F with the AWD t case. I wanted to go with this transmission as it’s an all hydraulic controlled trans mission so I does not need any ECU or wires connected to operate. After a short hunt I found what I needed in LA, it was an A440F with t case and converter for $100 with 200k miles on it and out of a truck that was driving before it was parted. I got the transmission shipped up for $100 by a cruiser guy headed home from LA for the holidays. The guy I got the trans from was good enough to ship my converter off to Road Runner converters in Phoenix AZ for a full rebuild and stall down to 1600 RPM. Thanks to Longbow (Don) for their information and all the information and help along the way.
So that gets me to about present with my journey. The following pages and posts will follow my swap and its components.
1 - 20 of 383 Posts
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So as with any build of this nature I want to make sure that what I am putting in will be as reliable as or more so than what I am replacing. I got the engine with the assumption it was a core that I could use as a starting point. One benefit to the Isuzu 4BD is that they are a sleeved block meaning as long as the block and crank stay in good shape (no holes) they can be rebuilt infinitely. I was pleasantly surprised at the exterior condition of the engine when I got it, it was not a rust ball or grease ball like some I had seen. So I started with turning it over with the large ratchet and breaker bar to make sure it was not seized, it turned well and felt like there was lots of compression. From there I drained out the oil (no metal bits good sign) and replaced the filters and oil. I then took a small bottle of Diesel and purged the system of air. After that I hooked up a battery to see if it would fire…….it fired with in ¼ of a turn and startled me and everyone else gathered around the see the attempt. Remember this engine was in unknown condition and had sat in a container for god knows how long.
So knowing it ran and ran well I had a surge of optimism. I did find that under a steady RPM over idle it would miss and pump out white smoke (unburnt diesel). I started by checking the injection timing, there are two small covers on the cam and injection pump gear, they line up with the crank damper when at TDC. I got my crank damper lined up with the mark on the case and popped off the injection pump inspection hole and there was nothing lined up with the arrow. I slowly turned the crank till the marker came into the sight, I had rotated the crank about 40* by the time it lined up. I was a bit blown away by this but it ran so well (other than the miss) that I could not believe it was that far off. I them looked at the cam mark and it was lined up with the injection pump mark. I then shifted my attention to the crank damper, knowing there is a possibility of it slipping.
Video of the miss:
Injection pump timing mark:
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Cam timing mark:
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Damper timing mark:
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So with the cam and injection pump lining up I had to assume it was the damper having slipped. I had read some info and used a Diesel Purge in the past with a few diesels with limited success, mainly just a better idle and less knock. So I thought I would give it a shot with this, I could only assume after searching on 4BTswaps that I was dealing with a pump issue. So I got two cans of the diesel purge and ran the engine on it straight not mixed. It was amazing with in 2min of running on this stuff it was totally gone, no more miss or white smoke my father and I where both shocked. I was not complaining it saved me a $700 rebuild for nothing.
Video after 2min of running on the purge:
So with it running better I went on line and found a Isuzu dealer selling NOS damper for $75 and got it. I could have ran the old one but wanted to make sure if I needed to check timing I would not have issues in the future plus I knew it was wrong.
While I was waiting for the damper to arrive I ordered a Fel-Pro engine overhaul gasket kit, it’s got every seal and gasket and the head gasket is a nice OE style malty layer metal gasket. The crank rear and front seals look great OE quality as well. So I think at $160 from Rock Auto it was a good deal.
Since I was waiting on all of that I figured I should take off the Valve cover and take a peak and set the valve adjustment. When I took off the cover I found a surprise. It looked as though it had just been redone, I could see where the rocker shaft brackets had been scrubbed in a solvent tank. It was also about the cleanest diesel I had ever seen under the valve cover.
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In this picture you can see how it was cleaned up.
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I was optimistic it was going to prove to be a good rebuilt engine (note I said was).
Within a few days both my crank damper and gasket kit got here and I got a 4:1 torque multiplier to get the crank nut off………even still I almost had a hernia getting it off. Once it was off I decided to take a look under the timing cover and make sure everything was good, also make sure it was done right.
So with the Isuzu 4BD it’s a very easy engine to set the timing on you line up the crank, cam and injection pump to the idler gear. The idler gear has an A,B and C stamped on it. All you do is line up A-A, B-B and C-C. A being the crank, B the cam and C the injection pump. When I got the timing cover off I found who ever had rebuilt this engine had forgone that small detail……
Crank:
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Cam:
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Injection pump:
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So knowing it ran and ran well I had a surge of optimism. I did find that under a steady RPM over idle it would miss and pump out white smoke (unburnt diesel). I started by checking the injection timing, there are two small covers on the cam and injection pump gear, they line up with the crank damper when at TDC. I got my crank damper lined up with the mark on the case and popped off the injection pump inspection hole and there was nothing lined up with the arrow. I slowly turned the crank till the marker came into the sight, I had rotated the crank about 40* by the time it lined up. I was a bit blown away by this but it ran so well (other than the miss) that I could not believe it was that far off. I them looked at the cam mark and it was lined up with the injection pump mark. I then shifted my attention to the crank damper, knowing there is a possibility of it slipping.
Video of the miss:
Injection pump timing mark:
Cam timing mark:
Damper timing mark:
So with the cam and injection pump lining up I had to assume it was the damper having slipped. I had read some info and used a Diesel Purge in the past with a few diesels with limited success, mainly just a better idle and less knock. So I thought I would give it a shot with this, I could only assume after searching on 4BTswaps that I was dealing with a pump issue. So I got two cans of the diesel purge and ran the engine on it straight not mixed. It was amazing with in 2min of running on this stuff it was totally gone, no more miss or white smoke my father and I where both shocked. I was not complaining it saved me a $700 rebuild for nothing.
Video after 2min of running on the purge:
So with it running better I went on line and found a Isuzu dealer selling NOS damper for $75 and got it. I could have ran the old one but wanted to make sure if I needed to check timing I would not have issues in the future plus I knew it was wrong.
While I was waiting for the damper to arrive I ordered a Fel-Pro engine overhaul gasket kit, it’s got every seal and gasket and the head gasket is a nice OE style malty layer metal gasket. The crank rear and front seals look great OE quality as well. So I think at $160 from Rock Auto it was a good deal.
Since I was waiting on all of that I figured I should take off the Valve cover and take a peak and set the valve adjustment. When I took off the cover I found a surprise. It looked as though it had just been redone, I could see where the rocker shaft brackets had been scrubbed in a solvent tank. It was also about the cleanest diesel I had ever seen under the valve cover.
In this picture you can see how it was cleaned up.
I was optimistic it was going to prove to be a good rebuilt engine (note I said was).
Within a few days both my crank damper and gasket kit got here and I got a 4:1 torque multiplier to get the crank nut off………even still I almost had a hernia getting it off. Once it was off I decided to take a look under the timing cover and make sure everything was good, also make sure it was done right.
So with the Isuzu 4BD it’s a very easy engine to set the timing on you line up the crank, cam and injection pump to the idler gear. The idler gear has an A,B and C stamped on it. All you do is line up A-A, B-B and C-C. A being the crank, B the cam and C the injection pump. When I got the timing cover off I found who ever had rebuilt this engine had forgone that small detail……
Crank:
Cam:
Injection pump:
2
Needless to say I was surprised and a bit shocked it had ran so well, I have a feeling they got it timed almost right, the cam was one tooth off when I reset the idler gear. Feeling a bit worried about the quality of work in the rest of the engine I was going to take a close look at everything else. First issue was the bussing/bearing on the idler gear.
Idler bushing/bearing:
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It had a few grooves I could catch a fingernail in two small what looked like FOD. This is not a serviceable item and is replaced with the entire gear. Ugh, only $175 from a local dealer though with no discount.
I then at a glance of the crank gear something caught my eye, I looked closer and found this.
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Double ugh, looks like the hardening of this gear is breaking down so replacement time. $105 from local dealer.
I’m now at the point where I do not trust anything that was done on this motor when it was rebuilt. So it was time to really dig in. It’s almost impossible to remove the crank gear from the crank in the block, the manual shows a puller but I could not find one that move it at all. I tried heat as well with no luck. So removing the crank to have the gear taken off may have/be my only option.
The rest of the gears in the timing case are good and have no damage at all. So that was looked upon as a victory
Idler bushing/bearing:
It had a few grooves I could catch a fingernail in two small what looked like FOD. This is not a serviceable item and is replaced with the entire gear. Ugh, only $175 from a local dealer though with no discount.
I then at a glance of the crank gear something caught my eye, I looked closer and found this.
Double ugh, looks like the hardening of this gear is breaking down so replacement time. $105 from local dealer.
I’m now at the point where I do not trust anything that was done on this motor when it was rebuilt. So it was time to really dig in. It’s almost impossible to remove the crank gear from the crank in the block, the manual shows a puller but I could not find one that move it at all. I tried heat as well with no luck. So removing the crank to have the gear taken off may have/be my only option.
The rest of the gears in the timing case are good and have no damage at all. So that was looked upon as a victory
8
Since I knew I was going to be tearing an engine down I spent a day clearing out some shelving and getting everything cleaned up and ready.
Once I have that all done it was time to pop the pan off, I found once it was off that the bottom of the pan was full of gray silicone, the kind you get when you use to much (my engine had everything sealed with gray silicone). There was also some ground metal in the bottom that looked to be from maybe the crank gear, there was also some aluminum dust. I got that all cleaned out without taking a picture for whatever reason. I did get a picture of the oil pump pick up screen though.
Oil pump Mohawk!
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Oil pump looks new, so may have been replaced when it was rebuilt?
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I cannot describe how massive every part is in this bottom end. The main bolts are huge!
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So leading up to this my main worry now was if the crank had been machined down, they are nitride treated like Toyota cranks and should not be machined. They just do not last once they are. Anyway moment of truth…..
Awww yeah!
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Crank looks good:
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Bearings looked new but showed signs of a hasty rebuild:
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I have not checked the mains but if the crank was to need machining anywhere it would be the rod bearings. I’ll get those out this week.
So with that out of the way it was time to move on, let’s take off the head!
Once I have that all done it was time to pop the pan off, I found once it was off that the bottom of the pan was full of gray silicone, the kind you get when you use to much (my engine had everything sealed with gray silicone). There was also some ground metal in the bottom that looked to be from maybe the crank gear, there was also some aluminum dust. I got that all cleaned out without taking a picture for whatever reason. I did get a picture of the oil pump pick up screen though.
Oil pump Mohawk!
Oil pump looks new, so may have been replaced when it was rebuilt?
I cannot describe how massive every part is in this bottom end. The main bolts are huge!
So leading up to this my main worry now was if the crank had been machined down, they are nitride treated like Toyota cranks and should not be machined. They just do not last once they are. Anyway moment of truth…..
Awww yeah!
Crank looks good:
Bearings looked new but showed signs of a hasty rebuild:
I have not checked the mains but if the crank was to need machining anywhere it would be the rod bearings. I’ll get those out this week.
So with that out of the way it was time to move on, let’s take off the head!
12
From there I started taking off all the bits to get the head off. First was the thermostate housing……ummm this is why you need to run coolant even in warm locations…..
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So even you guys living in warm climates that do not think they need coolant……let this be your lesson.
The head came off easily, all the head bolts where tight and gave a good snap when loosened. We lifted the head out of the way and the gasket was in good shape.
Cylinders all looked good……no wait I know you still think you are ok running straight water.
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Ok so you are going to ad coolant now right?
So onto the cylinders, the wall look good no bad scoring or anything, I can see a crosshatch still on all of it but the very top where the piston changed direction. Pistons look good as well, no cracks or damage from high EGT’s or FOD.
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So even you guys living in warm climates that do not think they need coolant……let this be your lesson.
The head came off easily, all the head bolts where tight and gave a good snap when loosened. We lifted the head out of the way and the gasket was in good shape.
Cylinders all looked good……no wait I know you still think you are ok running straight water.
Ok so you are going to ad coolant now right?
So onto the cylinders, the wall look good no bad scoring or anything, I can see a crosshatch still on all of it but the very top where the piston changed direction. Pistons look good as well, no cracks or damage from high EGT’s or FOD.
5
One issue I did fin is this:
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It looks like when the engine was being rebuilt they slid something across the deck on this cylinder and put a nice gouge through it and the sleeve. You could even see on the head gasket where this section had not made contact. It would have for sure caused a head gasket failer if not fixed. So the gouge on the block is not a worry, it does not bridge any oil or coolant passages. The gouge on the cylinder liner means it’s time for a new sleeve and what the hell since I am doing one why not do them all. Also note the last picture of the gouge to coolant passage getting plugged up with rust…….anyone still not want to run coolant? Oh well then here….
Oil cooler:
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So this gets me up to date so far.
Plan now is to totally strip the block and head so they can be put in a hot tank for a week to try and get rid of the rust…..any other suggestion?
It looks like when the engine was being rebuilt they slid something across the deck on this cylinder and put a nice gouge through it and the sleeve. You could even see on the head gasket where this section had not made contact. It would have for sure caused a head gasket failer if not fixed. So the gouge on the block is not a worry, it does not bridge any oil or coolant passages. The gouge on the cylinder liner means it’s time for a new sleeve and what the hell since I am doing one why not do them all
. Also note the last picture of the gouge to coolant passage getting plugged up with rust…….anyone still not want to run coolant? Oh well then here…. Oil cooler:
So this gets me up to date so far.
Plan now is to totally strip the block and head so they can be put in a hot tank for a week to try and get rid of the rust…..any other suggestion?
That stamped in B is the grade of your cylinder liner. If you can get graded cylinder liner kits then you'll be well ahead for NVH, particularly at idle. It seems none of the aftermarket rebuild kits are graded for fit, they are all "loose". They work, but the engine is noisier and you'll have more blowby.One issue I did fin is this:
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For this reason I'd be tempted to not replace working pistons/rings/liners and possibly get a B grade 4BD2T liner only.
I can't think of any easy repair options that would let you keep that liner in.
My 4BD2-TC water pump was weeping out the drain hole so I replaced it then.
I hadn't noticed your alternator and AC mount brackets, I like them, what was the original application?
Too bad you pulled it apart already, with that kind of scum in the cooling system I have had good luck flushing with cheapo white vinegar.
Drain the water, fill with vinegar, run to full temperature a time or two, drain, flush with LOTS of water, or water and the a weak baking soda solution.
I have had some freeze plugs "spontaneously" leak (after all the crap behind them falls out) but they are easy enough to change.
When you drain it the first time after doing that (for anyone that tries Vinegar) be ready to have some real ugly, chunky goo come out.
I hadn't noticed your alternator and AC mount brackets, I like them, what was the original application?
Too bad you pulled it apart already, with that kind of scum in the cooling system I have had good luck flushing with cheapo white vinegar.
Drain the water, fill with vinegar, run to full temperature a time or two, drain, flush with LOTS of water, or water and the a weak baking soda solution.
I have had some freeze plugs "spontaneously" leak (after all the crap behind them falls out) but they are easy enough to change.
When you drain it the first time after doing that (for anyone that tries Vinegar) be ready to have some real ugly, chunky goo come out.
Yes I wish I had known it was that bad when I started but this way I get it all cleaned out with a bonus of a fresh rebuildMy 4BD2-TC water pump was weeping out the drain hole so I replaced it then.
I hadn't noticed your alternator and AC mount brackets, I like them, what was the original application?
Too bad you pulled it apart already, with that kind of scum in the cooling system I have had good luck flushing with cheapo white vinegar.
Drain the water, fill with vinegar, run to full temperature a time or two, drain, flush with LOTS of water, or water and the a weak baking soda solution.
I have had some freeze plugs "spontaneously" leak (after all the crap behind them falls out) but they are easy enough to change.
When you drain it the first time after doing that (for anyone that tries Vinegar) be ready to have some real ugly, chunky goo come out.
Im really hopeful that the machine shop hot tanking can take care of it. I have had lots of blocks done but none this rusty.
Good to know about the water pump, im sure it will give me some notic if it starts to go bad.
1 - 20 of 383 Posts
