1992 isuzu to diesel TDI swap

superhl

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2002 new beetle
You may find googling specs of a particular size/bore master cyl. Sometimes using orileys/AutoZone etc look up it will have the specs in the description. Obviously aftermarket wilwood eastwood etc racing brands will list bore stroke and everything else.

With that being said if you are using the clutch out of the same vehicle your transmission came out of you already know you have the proper internal slave.

If you find them on google it will most likely be to a thread where someone has done an nv4500 or 3500 tranny swap in a jeep or Toyota or other vehicle and had similar issues.

I want to say the 4500 and 3500 had the same internal slave or maybe its an assembly with the hose attached. Its been ages since i looked into those transmissions in detail.

My low profile clutch choice was to help me not have to mix and match master/slave cylinders and reduce headache on swaps. You learn more on your first conversion than any other.


I did a quick Google search. Many people use the nv3500 in different swaps to get a cheap mt with od swap. Many have had throw issues

It appears that Some say the slave should ride the fingers at all times. Some say a .060 gap. Spacers can be purchased to make it sit closer. If your isuzu had the same master cyl as a blazer you should be good with your master cyl. The full size and blazer/s10 nv3500 are all integrated bellhousing and should have the exact same depth from one to another. Should is the key word here. The shifters are probably shaped differently.
Here are the bore sizes.
Isuzu 1992 clutch master: Integral Reservoir Type, 0.630 in. Bore Size
1994 4.3 S10 nv3500: Master Cylinder Bore Diameter (in): 0.88
 

superhl

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2002 new beetle
slave doesn't have standard bleeder for connecting tube

Before you go randomly replacing hydraulics check the sizes and strokes of the parts. If the original master for the slave was larger, you will need larger, also if the stroke is different you need to make up with size or stroke, if you can or get more stroke. Hydraulics are mathematically predictable assuming all is bled well.

For stubborn bleeding of any brake or clutch I resort to running a tube from the bleeder to the reservoir and opening the bleeder and pumping the pedal till all bubbles are long gone, then close the bleeder. You don't waste much fluid as you are just cycling it through.
I tried uploading a picture but for some reason would not permit. Here is a link to the type of slave that i have. At the bottom of the neck is a pin hole that release the fluid. Not easy to bleed.
 

superhl

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2002 new beetle
I tried uploading a picture but for some reason would not permit. Here is a link to the type of slave that i have. At the bottom of the neck is a pin hole that release the fluid. Not easy to bleed.
 

PickleRick

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Nov 29, 2017
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Greenville sc
TDI
05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
If you don't have a hand held brake bleeder pump id borrow or buy a cheap harbor freight one.


Take some tight fitting hose and attach it to the nipple and back to your pump. Pump until all bubbles are gone.

You have a smaller bore master cyl but that isn't a guarantee your issue isnt from air still in the line.
 

pdq import repair

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idaho
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09 Jetta
The smaller bore will shorten the stroke at the slave, unless the master has a much longer stroke than the bigger one. Pedal resistance will be low also.
 

superhl

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2002 new beetle
If you don't have a hand held brake bleeder pump id borrow or buy a cheap harbor freight one.
Take some tight fitting hose and attach it to the nipple and back to your pump. Pump until all bubbles are gone.
You have a smaller bore master cyl but that isn't a guarantee your issue isnt from air still in the line.
I will give that a try. I did borrow a loaner vacuum pump from Autozone and connected it to the reservoir. There were continuous small bubbles. I am thinking maybe a line has a pin hole?? I am going to replace the lines. Everything else is new. If the bore is too small and it shortens the stroke, then I need to place it. If the master is too small, it should still pump up to a hard brake. Right?
 
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superhl

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2002 new beetle
The smaller bore will shorten the stroke at the slave, unless the master has a much longer stroke than the bigger one. Pedal resistance will be low also.
Any master cylinders that you recommend?? Is there a universal that will match the slave?
 
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pdq import repair

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idaho
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09 Jetta
I don't know of anything offhand. That is the joy of swaps, working out the details. Maybe someone on the internet has already figured this out. If not then it is research time. you may be able to find a master with the same bolt spacing and bore size and stroke you need and have to fab up some lines and reservoirs to fit.
 

PickleRick

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Nov 29, 2017
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Greenville sc
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05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
Proper bore/stroke or not the pedal should not be squishy. Its not different than brakes. A larger diameter bore means a heavier pedal due to a loss of leverage and more fluid being moved. A smaller bore means less fluid being moved nut a lighter pedal. Still there should be no squish.

When i set up a custom clutch i like as little flex as possible and as much hard line as possible. I prefer stainless braided brake line over rubber. The less flex the line gives the more force the slave receives hince the popularity of stainless braided brake lines.

I like 10 inches or less of proper sized braided line and the rest all solid. Usually you dont have pin holes in the lines unless old and rusty but ive had many compression fittings leak even my newly cut and flaired ones require close inspection and i put a little dab of brake fluid on my flair tool as well as fittings when flairing and assembling to help make a smooth mating surface. I purchased a 50 ft roll or solid brake line years ago and has helped me compete serval builds.


Once you are 100%sure the entire line has been bled and you know your clutch pedal is adjusted properly then I'd first try a blazer master cylinder since you can get it at the local auto store and return it if it doesn't fit.


Another thought before doing that.

Many clutch pedals have 2 adjustments. One is where it stops. Bring the pedal away from your master cylinder as far as possible, this will allow more travel. Then adjust your push rod to give the most throw possible. You want to use every possible MM of throw that master cylinder has if you are not properly disengaging. Obviously there should always be a slight resistance to the clutch pedal. You should never have free travel before you feel any resistance.

If possible habe the back tires off the ground and have someone push in the clutch while trying to spin the drive shaft. If they can you know it's close.
 

superhl

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27534
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2002 new beetle
Proper bore/stroke or not the pedal should not be squishy. Its not different than brakes. A larger diameter bore means a heavier pedal due to a loss of leverage and more fluid being moved. A smaller bore means less fluid being moved nut a lighter pedal. Still there should be no squish.
When i set up a custom clutch i like as little flex as possible and as much hard line as possible. I prefer stainless braided brake line over rubber. The less flex the line gives the more force the slave receives hince the popularity of stainless braided brake lines.
I like 10 inches or less of proper sized braided line and the rest all solid. Usually you dont have pin holes in the lines unless old and rusty but ive had many compression fittings leak even my newly cut and flaired ones require close inspection and i put a little dab of brake fluid on my flair tool as well as fittings when flairing and assembling to help make a smooth mating surface. I purchased a 50 ft roll or solid brake line years ago and has helped me compete serval builds.
Once you are 100%sure the entire line has been bled and you know your clutch pedal is adjusted properly then I'd first try a blazer master cylinder since you can get it at the local auto store and return it if it doesn't fit.
Another thought before doing that.
Many clutch pedals have 2 adjustments. One is where it stops. Bring the pedal away from your master cylinder as far as possible, this will allow more travel. Then adjust your push rod to give the most throw possible. You want to use every possible MM of throw that master cylinder has if you are not properly disengaging. Obviously there should always be a slight resistance to the clutch pedal. You should never have free travel before you feel any resistance.
If possible habe the back tires off the ground and have someone push in the clutch while trying to spin the drive shaft. If they can you know it's close.
I have rear end of raised off the ground with a cherry picker. I adjusted the push rod as far out as possible. I am going to replace the line and try to bleed again. I will let you know. Thanks
 

superhl

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27534
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2002 new beetle
I replaced the master cylinder with a 1994 S-10 master cylinder and new line. Hopefully if I can find time, bleed the clutch tonight.
 

superhl

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2002 new beetle
How did the slave cylinder swap go?
Since the tranny came out of a s10, I decided to purchased a new 1994 chevy S-10 master cylinder and fabricated so it would fit the Isuzu pickup. My mechanic stop by and we attempted for two hours to get a hard pedal. No luck. He is thinking the new master cylinder is bad. However, I can remove it from the firewall with line intact. Turn the reservoir upright where the reservoir is higher than the push rod. Make short pumps to the point we can no longer move with throw rod. On the slave end, I can bleed it and will have great pressure. Once I reconnect to firewall, I have no hard and no fluid making it to the slave. I was busy last night so could not attempt to try again. I left the reservoir high since Tuesday and hopefully if there is any air it will bleed out. I am going to try again tonight and if no luck order another master. I am looking a hose that will fit the slave and run it back to the reservoir.
 

superhl

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I have a hard clutch! Leaving the reservoir up high must have allowed all the air to move upward. When I installed it, I had a semi hard clutch. We then bled the slave and clutch fully disengages allowing the gears to change smoothly. I created another problem, I broke my clutch safety switch but that is an easy fix. Time to clean up the wiring and build a dongle for the map sensor. Thanks for all the help
 

A-man930

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St. Louis
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Planning Stages: ALH Jeep MJ
I like 10 inches or less of proper sized braided line and the rest all solid. Usually you dont have pin holes in the lines unless old and rusty but ive had many compression fittings leak even my newly cut and flaired ones require close inspection and i put a little dab of brake fluid on my flair tool as well as fittings when flairing and assembling to help make a smooth mating surface. I purchased a 50 ft roll or solid brake line years ago and has helped me compete serval builds.
Couple of thoughts:
-Compression fittings have ZERO place in clutch or brake hydraulic systems (especially brakes). The OEMs aren't dumb; SAE or DIN flares are the way to go for safety/reliability and they're not that hard to do.
-I also normally use a dab of brake fluid on the flaring tool for lube but have on several occasions (w. steel line) used GL5 gear oil instead for it's high-pressure lube properties with great results. This obviously has to be flushed out very thoroughly; I've only been brave enough to try this when working with a line on the workbench so I can clean the snot out of it.
-I have recently converted to using copper/nickel in place of steel, coated steel, or stainless. To those who haven't tried this stuff out it is amazing. Easier to flare, easier to bend, and inherently corrosion-proof but still rated for brake system pressures.
OP glad to hear keep it up :cool:
 

PickleRick

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Greenville sc
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05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
Sweet! Glad to hear.

And sorry i meant flare fittings not compression fittings, proper terminology of hydraulic/hose fittings is not my strong suit. I have a bin full of fittings, residual valves and rolls of brake/clutch hard line at the shop when the need arrives.

I bet the copper (also what i use for boat steering hydro lines) are a huge upgrade. I have been using 3/8 refrigeration lines for that but what you find at lowes/home depot is now too thin and cheaply made. I need to find another source. Rubber flex hose makes hydralic helm steering too tight because of the flex in the lines. The solid lines really help you to have that one finger steering. Proper size helm and ram obviously.
 

superhl

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Jul 21, 2017
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27534
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2002 new beetle
Is this the location of the oil sensor? Looking the the bentley, I can't tell.
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PickleRick

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05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
I'll be 100% honest and say i have no idea. My swap is still in the i own a boat and i own several donor passats to choose from stages.

It looks to be in the proper location for the oil sensor as under a pressurized oil cooler would make for a sensible spot, i believe on the other side of that you'll find a plug where you can remove/install your aftermarket oil sensor or hose dor sensor.
 

superhl

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27534
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2002 new beetle
I'll be 100% honest and say i have no idea. My swap is still in the i own a boat and i own several donor passats to choose from stages.

It looks to be in the proper location for the oil sensor as under a pressurized oil cooler would make for a sensible spot, i believe on the other side of that you'll find a plug where you can remove/install your aftermarket oil sensor or hose dor sensor.
Thanks! Here are the gauges I purchased. As far as the coolant sensor, can I run a wire from the sensor back to the gauges or do I need to install the sensor that came with the gauges?



https://www.amazon.com/gp/product/B0788NSZNC/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1
 

PickleRick

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Nov 29, 2017
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Greenville sc
TDI
05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
You'd have to find out what the ohm reading are for each sender and then find a gauge that is compatable.
 

superhl

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27534
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2002 new beetle
giving power to exciter (blue) wire

My Isuzu does have a cluster light but it connects from ignition to ecm. What is a work around to connect and give power to the blue exciter wire?
 

IdontownaVW

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Oct 10, 2010
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Wilmington DE
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MK1 AHU, Colorado Duramax
My Isuzu does have a cluster light but it connects from ignition to ecm. What is a work around to connect and give power to the blue exciter wire?
Before I found the proper wire on my fuse box(mk1 tdi swap) I was informed that wiring the exciter wire to switched 12v does the trick.
 

superhl

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2002 new beetle
IdontownaVW,
Thanks! I read on another site that the 12v was too much and would burn up the alternator. Wouldn't I need a resistor?
 

superhl

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2002 new beetle
I ordered a small LED light and wired one end to the blue wire and other to the switch. Works perfectly! Thanks
 

superhl

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2002 new beetle
engine cranks fast but start after 4 or revolutions

I ordered a Vagcom VCDS and should arrive any day for troubleshooting. When cranking the engine, it takes 4 or 5 revolutions before it will start. After starting runs great, lots of power! The battery is one year old and rotates the engine fast(not sure it reaches the required RPM's. Maybe the VCDS will tell me. I read somewhere that the ECM will not supply fuel to pump if the RPMs are not reached. I re-tightened fuel lines, thinking about running straight steel pipe eliminating rubber hoses. The lift pump is two years old. I have a "T" between the fuel supply line and return line. Thinking maybe I need a valve to prevent fuel from leaking down. I can turn the engine over one revolutions, shut off key, try again and engine will start on one or two revolutions. Does not matter if hot or cold? Any suggestions?
 

Motohead1

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charlotte
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2002 bug+telephone pole
What do you mean you have a T between supply and return? if you dont return fuel to the tank its gonna cook along with other issues.
 
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