What 4.2 turbo to do direct replacement with no mods

[Ricor]

I have not been able to find an answer to my question - Is my turbo bad? I just bought a 1996 GQ 4.2 turbo. It is super slow, 15-22 seconds 0-60mph. I hold up traffic every time I travel. Top speed is only 63mph. Runs smooth and has a decent pull at low rpm's. Low speeds runs great, and runs great if you go slow and accelerate slowly. very slowly.

I am assuming at this point the turbo is bad. I am a lifelong petrol and marine mechanic, but not a turbo guy and only slightly a diesel guy.

I would like to find an affordable turbo to swap out to see if this is the issue. If I can increase performance a little without additional mods that would be great.

Any advice?

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[Cremulator]

The first thing I would do is buy and fit a cheap boost gauge. Use a plastic T piece and just run the hose out from the bonnet and in through the drivers window.
Take it for a drive and check what the turbo is doing.
This will tell you if it's producing any boost and how much.

If the turbo is not working, then you can look to replace it.

[Cremulator]

Also, looking at the factory specs here, it states the 1996 GQ safari 4.2 turbo diesel is estimated to accelerate from 0-60mph in 15.2 seconds, so you might not be far off experiencing its performance from factory!
https://www.automobile-catalog.com/c...bo_diesel.html

[Ricor]

Great idea. Where do i hook up the boost gauge? It might be obvious, I have not looked yet.

[geoffayres]

If the gauze strainer is still present in the fuel injection pump inlet it might be restricted.

I'd check that before doing anything else.

[MudRunnerTD]

The first thing I would do is buy and fit a cheap boost gauge. Use a plastic T piece and just run the hose out from the bonnet and in through the drivers window.
Take it for a drive and check what the turbo is doing.
This will tell you if it's producing any boost and how much.

If the turbo is not working, then you can look to replace it.

This is my exact go to for sure. The black hose coming out of the side of the top cross over pipe will be a boost line maybe to the pump. T connector into that and just run a hose into the cab through the window and hook up a boost gauge without going through the install. You should have a Boost gauge and an Exhaust temp gauge regardless so look at doing that.

Note a Turbo Petrol and a Turbo TD42 are un-comparable. Get that TD into low range and it will climb a pyramid. That is where the turbo power really is. To see the true capabilities of the TD requires a big turbo and 12mm pump and Intercooler and a good dyno tune.

Where are you located on the planet mate? do you have access to a Dyno Tune? if so fit the boost and EGT gauges and then get it onto a Dyno. If there is No Dyno then fit the gauges and find the fuel screw on the back of the pump. You could give this a tickle and take it for a drive. The factory setup is a 10mm pump de-tuned to buggery, a turn or 2 will make a big difference. But it wont be a race car.

on teh factory spec it will be running 9psi of boost and low fuel settings. You could comfortably boost it up to 12 to 14psi all day. EGT temps of 350c is nice with a top out at 500c. If there is Black Soot then you have too much fuel or not enough boost. add boost.

Have fun mate.

[Ricor]

Great info, going to require a little figuring out though.

I am in the US, the Florida Keys. I live on an island, no dyno for 200 miles. No help either. As usual, I have to figure this out on my own. Well with help from you crazy Aussies now I really appreciate the advice.

I am planning on taking this Patrol with me when we move to Fiji, hopefully next year.

Feel free to point out anything I need to know in the pictures above.

[Ricor]

We are having a laugh. My wife has been my right hand in everything for over 20 years. I built and raced cars through high school, we have had 20 boats over the years (I am a Captain and we are both scuba instructors) so I do know a bit. We were just looking at these pictures and she asked, What is that? - I don't know. What is that? I don't know. What is that? I don't know. Laughing ensued.

As always, I'll get it - eventually.

I LOVE this truck and the TD42 is one hell of an engine.

[Ricor]

Just took the Patrol up to work, and used a stopwatch to time 0-60. 39.27 seconds. We definitely have a problem. Runs smooth, just slow. My money is on a turbo problem. Boost Gauge will be here Saturday.

[geoffayres]

It will not make boost without fuel.

Change the fuel filter if not done recently.
Check the gauze strainer (it's under the injection pump inlet banjo bolt, deep inside the pump).

Start with the simple things....

http://www.nissanpatrol.com.au/forum...change-on-td42