Builds The Journey Begins...

[Dougal]

20psi with the 54 mm T25 and intercooler! I did not expect those numbers and thought 14 was good?

I am using the stock Isuzu intercooler, which appears to be a good unit. The IC is the smaller one that came with free floater turbo engine, I have the IC that came with the later model engine that is almost twice as large. I may try to mount the bigger IC soon.

As far wheel size, I did not measure it, as I thought they were all 54mm. I will call the turbo shop and see if they have have the old wheel to measure.

I am using a manual waster gate controller between the turbo and the actuator. The boost setting on it is wide open, I wonder if the spring rating is too low, allowing the actuator to open at 14psi? I am going to wire the actuator closed and give it a run to see if the controller is limiting the boost, or something else.

What do you guys think is a safe egt to run on a regular bases? I have always tried to limit egt's to 900-1000f for regular driving, climbing to 1100f with short periods of 12-1250f. Currently, the max egt reading has been 1200f. Maybe more fuel to make more boost?

Another test I will try is to remove the air filter lid and element to see of air flow is restricted. I have the Toyota big canister housing, paper element being fed from a snorkel. I have the stock Isuzu air filter restriction gauge, and it stays in the green, but maybe the turbo fools it?

I will let you know what I find.

Doug

I'm running 20psi with the 51.3mm T25.

Yes you will struggle to get past 14psi boost with a soft actuator. I couldn't hold 20psi boost until I had a 22psi actuator with an additional 4mm of preload on it.
For this reason alone manual boost controllers are useless on diesels. Leave them to the ricers who need to go from 5psi to 9psi. For our uses drive pressure against the wastegate is a significant contribution and needs a serious spring to hold it back and maintain boost.

Clamping the wastegate shut will show higher boost, but it'll also kill power as the turbine alone can't pass enough exhaust gas. You need a properly matched actuator which just cracks open at target boost and keeps bypassing more and more exhaust around the turbine as flows increase.

1400F does not hurt these engines. Put your own safety factor on that. I have seen 900C (1650F) accidentally.
The stock intercooler should be quite good. Run a temp probe on the outlet and see what you get.

 

[Dazed]

Doug
Did you do anything to your stock speedometer to make it give you an accurate speed for the H55f with 33s?

 

[doug720]

I wanted to give a little update on the turbo swap I recently made. I swapped the stock free floater turbo for a later model 4BD2 waste gated turbo. I had the turbo rebuilt as the condition was unknown.

The waste gated turbo is basically a bolt on replacement for the free floater, all the oil and coolant lines, intake, etc swap right over. I had to make a new exhaust down pipe, but had wanted to do that anyway to re route that section anyway.

Performance wise, it came out great. I get a little turbo whistle and am seeing boost up the 16-17 psi range. The egt's are lower and it goes really well. I also adjusted the IP pump a little, turning the star wheel about 90-100 degree's toward the front of the engine. My max egts are around 1050 - 1075 while working hard and virtually no smoke. I cruise at 7-10 psi and 800 degrees @65+.

Last week I was in the Sierra's fishing for 4 days and was up around 8-8700' elevation. The new turbo works so much better. Boost starts sooner, pulls better and little smoke with low egt's. All these are so much better than the free floater turbo, plus I get the "Whistle"

On the way home we climb up the Grapevine from the central valley towards Gorman on the way to LA. This is a good climb with 6%+ grade. With a full load of camping gear, ice chest, 3 dogs, fishing stuff and roof rack, we climbed the grade in 5th gear...WITH AC ON(See blue AC light on dash)... at 73 mph at 14 psi with 975 degree egt's! 73 is faster than I normally cruise at (65), but that speed was a happy place for the engine to go up the hill, plus I was passing cars! Not too bad.

The turbo swap worked well for me performance wise, it kept all the stock oil and coolant connections and intake to for dependability. If you have a free floater and are looking for moderate performance gain, I would suggest this turbo.

Doug

PS - Mitch, my speedo is off by about 12%. Look at the picture below to see the difference. The stock speedo is reading about 63 and GPS reads 73 mph. I just deal with it. I normally cruise at 65 mph corrected which is just over 55 on the stock speedo.

 

[longbow]

Those are some great numbers Doug!

Enjoy!

Don

 

[Dazed]

The amplifier as I said is a gas model from something Toyota with the idle up feature, which is not supposed to work without a coil signal, but it does and I found out why!

I used the stock 2f coil signal wire to connect the hall effect injection pump sensor on the 4BD2 to run my tach with a Dakota Digital signal convertor. This sensor must mimic the coil signal and make the gas amplifier work.

This may be good news for other 4BD2 swappers who choose to the Isuzu IP rpm sensor on their 60's.

I am using the same coil wire for my tach sensor (just not using the dakota digital). This seems to mean that the stock amplifier should work without any modifications? Does that seem right?

 

[longbow]

Yes and no I think. It should work if you convert the pulses somehow to 3 pulses per revolution of the crank. Doug is using a Dakota digital to convert the pulses, how were you going to convert the multiple pulses coming off that IP gear to run yours?

I used a hall sensor on my harmonic balancer and it runs the tach but did not have enough juice to get the A/C amp going. My guess is that the Dakota converter puts out a stronger signal and that is why it works the amp.

Don

 

[doug720]

The RPM sensor on the 4BD2 produces an AC signal of around 15 volts if I remember correctly. I think it was dumb luck that the Isuzu sensor made the amp work, not the Dakota. I mounted the Dakota right onto the gauge cluster and well after the signal enters the AC amp. It's been a while, but I may still have my notes from sorting this out. I will look this afternoon.

If you use the Dakota, here are a few things I learned:

I wired the tach directly to the Isuzu sensor and it worked, but was not accurate. I spoke with Dakota tech support on what I wanted to do and they said it would work.

The Dakota converts the signal and allows correction to adjust the calibration. It worked out well.

If you use the Dakota, mount it somewhere that is easy to access for adjustment. Since mine is mounted to the back of the engine gauge cluster, I have to remove the cluster to make adjustments which is a pain. It takes quite a few adjustments to get it reading properly.

Is you're tach working? Just no AC signal? Is the tach accurate? How did you measure RPM?

Doug

 

[Dazed]

My tach works by using, what i think is a hall sensor on three cuts on the flywheel. It is very accurate when the sensor is close enough to the flywheel (as the flywheel heats up and expands away from the sensor, it stops working....need to adjust it soon). It is the same setup someone else had with their abs brake sensor.

So i am hoping that that sensor is strong enough (I must be due some dumb luck right!), it's supplied with 12v on one side and the magnetic sensor output on the other, to drive the amplifier, if Doug could drive his like he said and if the amplifier was already driven by the line from the coil.

I haven't tested any of this yet since I don't have all of my AC parts, but am trying to think ahead. I could get a multimeter on the to-AC-compressor wire and see it's voltage, but there will be no cooling coming from it at the AC temp sensor where ever that is located.

 

[doug720]

Hall effect sensors generate their own signal. I used that signal to feed the coil wire that is tied to the AC amp, and my tach via the Dakota.

You can test the plug on the AC amp to see if there is a signal. Search on mud for the AC amps plug pin schematic.

Another option is to run AC amp from a 62, as they don't require a coil signal. I ran a diesel AC amp till it died and was going to try the 62 amp when we found a gasser worked my my Hall sensor signal.

I would check the hall sensor output. It should be AC voltage and I would think you would need at least 8+ volts to trigger the AC amp.

If the sensor voltage won't work, I would use a 62 AC amp and be done with it.

Hows she running?

Doug

 

[longbow]

I would be surprised if the flywheel flexed away from the sensor. I would venture to say it is the same problem the rest of us have had with the hall sensor systems and the factory tach. Does it start cutting out after you reach 2100 to 2300 rpm and then start working when you get back below those rpms? The signal isn't strong enough to power the factory tach and begins to cut out at the higher rpms and we all didn't find it out until later when we had all installed them. ASTR has a thread where he addresses this issue and a fix with a couple new capacitors in the factory tach. I tried it with mine and I must have done something wrong because it killed the tach when I did it. I am eventually going to go with either the Dakota or the Autometer 2888 diesel tach. All of this doesn't help your A/C amp problem and so I would just do as Doug said and go with the 62 amp and make life simple. Finding a diesel amp proved very difficult for me and 62 amps are much easier to find.

Don

 

[Dazed]

It works at high speeds but only when the truck and such are cold and have been sitting. When it all warms up, it goes haywire all the time. I will try once more to get it closer and then if that doesn't work, try the IP sensor, although I think mine is busted.

Is the 62 amp a direct bolt on? I'm not even sure where it's located in the truck! I assume behind the dash.

It's running well. Didn't find it, but fixed an intercooler piping leak yesterday by tightening everything. And made a mount for my air oil separator. It seems to be running well. Just need to get a few things sorted so I can really drive it.

 

[doug720]

I wonder if the Hall sensor you have is breaking down from heat. Some electronics work when cold than start to go bad when hot?
Do you have another sensor to swap in?

I think you have a 4BD1, if so, there is no sensor on the IP. This is a 4BD2 part only.

The AC amp is mounted directly below the glove box in a molded case on the main AC plastic duct box. You will see it when you look, it has a wiring connector on top and a small snap clip holding it in place. Easy swap.

Glad you sorted the boost leak. If AC is not a priority, maybe drive it for a while, then sort the little things all at once. You are getting closer!

Doug

 

[Dazed]

I wonder if the Hall sensor you have is breaking down from heat. Some electronics work when cold than start to go bad when hot?
Do you have another sensor to swap in?

I think you have a 4BD1, if so, there is no sensor on the IP. This is a 4BD2 part only.

The AC amp is mounted directly below the glove box in a molded case on the main AC plastic duct box. You will see it when you look, it has a wiring connector on top and a small snap clip holding it in place. Easy swap.

Glad you sorted the boost leak. If AC is not a priority, maybe drive it for a while, then sort the little things all at once. You are getting closer!

Doug

Ive only driven it ~70 miles so I doubt it's broken down, plus Dustin said he has used these quite a bit. I just need to get it closer.

My IP gear has a magnetic sensor sensing it attached to the outside of the timing gear case.

I will check out the AC amp at some point but no it's not a priority. I think there may still be a small boost leak but it is not nearly as noticeable....if it's even real. A true priority is a radio!

 

[longbow]

Ah, ok now I get it. I thought you were using the sensor on the IP housing ( 4BD1Ts have them also if it had an auto tranny originally) .

 

[Dazed]

yeah, I had an auto tranny in mine.

And yay, 250 posts!

 

[doug720]

Learn something new everyday... I didn't think any of the 4BD1's had the IP sensor! So you have options if the ABS senor does not work.

I like all the pictures you posted in your thread. Your getting close!

Doug

 

[bluehawk]

Few Questions

With out multi quoting a bunch of your postings, got a few questions for you Doug.

Post 82: What is the line coming out of the turbo housing, EGT?

Post 114: In the third picture, is that big line a #12 ?

Post 119: In the third picture, where did you get the fitting that
you brazed on there and what size is it?

Post 130: Do your fuel lines run from your gas tank to the fuel
water seperator that you have and then to your stock
fuel filter?

Post 234: The banjo fitting that you are showing in picture one,
what size is it and then did you clamp the stainless
steel hose to the end that goes to the steel line in
post 235 the last picture?

Sorry for so many questions and all, getting ready to buy some AN fittings to tig weld onto the pieces that use to go to the top of the oil filter assembly and up to the side of the case. That's why I was asking if they were #12's or not. Will email you the other questions that I had for you. Thanks to you and Longbow (Don), I have gotten soooooo much info for putting my diesel engine back together. I have also gotten a ton of info from Dazed (Mitch) from watching his build and following his do's and dont's.

Thanks, Ryan

 

[doug720]

With out multi quoting a bunch of your postings, got a few questions for you Doug.

Post 82: What is the line coming out of the turbo housing, EGT?

Yes, EGT probe. On my new turbo, I had to move the probe to the exhaust manifold.

Post 114: In the third picture, is that big line a #12 ?

Yes, #12

Post 119: In the third picture, where did you get the fitting that
you brazed on there and what size is it?

Fitting is from Earls Supply (I have a main store nearby), I forget the tube size, but the hose size is #3. I bought an undersized tube size and enlarged the hole to fit the metric steel line size.

Post 130: Do your fuel lines run from your gas tank to the fuel
water seperator that you have and then to your stock
fuel filter?

Yes, basically stock lines to the added filter assy. sthen plumbed to the stock fuel filter.

Post 234: The banjo fitting that you are showing in picture one,
what size is it and then did you clamp the stainless
steel hose to the end that goes to the steel line in
post 235 the last picture?

That filtting connects to the steel IP fuel line you referenced in my post 119. #3 AN fittings on both ends of SS braided line.

Sorry for so many questions and all, getting ready to buy some AN fittings to tig weld onto the pieces that use to go to the top of the oil filter assembly and up to the side of the case. That's why I was asking if they were #12's or not. Will email you the other questions that I had for you. Thanks to you and Longbow (Don), I have gotten soooooo much info for putting my diesel engine back together. I have also gotten a ton of info from Dazed (Mitch) from watching his build and following his do's and dont's.

Thanks, Ryan

No problem and glad to help. I answered the email also.

Doug

 

[bluehawk]

Motor Mounts

Thought that I would come back over to your post and ask questions about the mounts, instead of asking on Dazed's thread. I looked at page 2 post 27 at your motor mounts. It appears that both mounts are the same length, would that be a correct statement? Trying to get a few things finished up on my motor before attempting to place it in the frame rails. Also, do you have any stock pictures of the A/C mounted before you modified your mount? Can't figure out how that sucker goes back on there. It was not on there when I bought the motor. Got a new belt for it also and not sure also how to set the tension. I have no mount bolts or anything.

Thanks Doug

 

[doug720]

The motor mount fame brackets are real close to the same length. The drivers side was the tightest fit on my swap and the steering box was the issue. I did the ac mount modification you mentioned and added a 1/2" steel spacer between the steering box and frame also. Works great.

These are the best shots I have of the AC compressor, if you want something specific let me know.

Hope these help.

I have been in the Sierra fly fishing and just checked in.

Doug