Turbocharging a Jinma 254 Build (Y385)

[sd455dan]

We will post more detail later, but I can give an overview of what we accomplished so far.

The GT15 turbo clone is installed. However, we are only getting 3 PSI boost max, typically it is closer to 2.5 PSI boost. This is from an oil-filled pressure sensor off the intake manifold (0-15 psi, after the turbo). The wastegate never activates, meaning we never hit 4 PSI

In terms of performance I brush-hogged the same deep grass, this time in 3rd gear without any drop in engine RPM. I could see the boost pressure rise up to 2.5PSI when I entered the deeper brush, and instead of having to shift down to 2nd gear I could stay in 3rd the entire time.

We have an engine exhaust temperature probe in the exhaust manifold prior to the turbo.
In the heaviest mowing I saw 500F, but typically it was around 400-420F with 375F in lighter grass.

The temperature was 180F max after 45 minutes of brush-hogging. We discovered the OEM thermostat was "stuck", after un-sticking it we measured 170-180F while mowing.
The high-flow thermostat did not allow the engine to warm up.... it stayed at 147F max with that thermostat in. Though we only rev'ed it up and didn't drive or mow with it while testing that high-flow thermostat.

We are still thinking about why our max boost is 3 PSI
- one small leak in the pressure sensor hose was uncovered and fixed (minor improvement), other pressure leaks?
- fuel adjustments - ****** fuel timing? Typically as boost pressure rises on a diesel you ****** up to 24 degrees before TDC
- other?

We will update with video's and pictures later, it was a busy weekend getting it all plumbed in and ready for testing.

Sounds like you are still getting a net improvement in performance:thumbsup: even with that small amount of boost.

Have you already cranked up the fuel screw?

Sounds like progress is being made and thanks for the update

 

[ElectroTechnics]

Sounds like you are still getting a net improvement in performance:thumbsup: even with that small amount of boost.

Have you already cranked up the fuel screw?

Sounds like progress is being made and thanks for the update

I turned the screw in, 1 and 1/2 turns and see 3 PSI boost on no load throttle up.
NOTE: The previous 3 PSI boost only happened when the tractor lugged down under mowing load in heavy brush
it would not show boost doing no load throttle up

I am about to do some test mowing to gather statistics from the gauges and check for black smoke under load
(if so I will back off a few 1/4 turns till it burns clean under load)

UPDATE after 20 minutes brush-hogging deep brush
There was no smoke under load so I could potentially increase the fuel a bit more.
When I hit the 4' brush in 3rd gear I could see the boost gauge jump up over 3 PSI
(I was filming the gauges so not sure how high it got, but it didn't hit 4 PSI)

That is an amazing power boost over stock as this brush would always force me into 2nd.
I also had the brush-hog implement scraping the ground to make more load.

Youtube video of it mowing under boost: (you can see the boost gauge at 19 seconds in and 58 seconds into the video)
https://www.youtube.com/watch?v=VYIahRzQovg
at 58 seconds you can also see the EGT at 550
Youtube overview video of new turbo: https://www.youtube.com/watch?v=AtJ4SDKzBeY

 

[ElectroTechnics]

After more tests this evening I have these observations about its operation:
(1) On a straight 1' high brush run with the brush-hog at it's lowest setting I see 1 to 1.5 PSI boost (to no boost over area's I already mowed)
(2) 1" diameter tree's in the heavy brush kicked boost pressure up to 3.2 PSI (no black stack smoke, just zipped right through it)
(3) The RPM never dropped a significant amount in the heavy brush (I'm staying in 3rd gear instead of downshifting to 2nd now)
(4) Water Temperature maxed at 180F (electric fan off, mechanical only) 93F, 65% humidity outside So the unstuck OEM thermostat works fine

There is room for more boost (increasing fuel more). It depends on how much stress I want to put on the engine as to how far we go. We could increase fuel to the point the wastegate operates at 4 PSI... right now I never saw it get close to opening the wastegate (we have a 7 PSI spring in the turbo actuator).

For fun here is a short no load throttle up video of the boost gauge: https://www.youtube.com/watch?v=lLQVTXUsVtM

 

[petar]

Now you need a continuous full load test, like a PTO dyno or pulling up a long hill with a loaded trailer.
If the EGT stays safe than you can call it a day.

Get some braided hoses made for the turbo oil lines !! You do not want those hose clamps to come off

BTW these engines are severally underfueled stock for low soot emmisions. On my 454 i've turned the full load screw to the point it smokes very lightly under full load and it made a huge difference in perfomance.

 

[SPIKER]

With the BOOST issue under normal conditions unloaded you shouldn't see much boost unless you are pushing against brake or load the engine should simply pass air on thru (no boost.) So that is normal for most part on low boost applications

M

 

[ElectroTechnics]

With the BOOST issue under normal conditions unloaded you shouldn't see much boost unless you are pushing against brake or load the engine should simply pass air on thru (no boost.) So that is normal for most part on low boost applications
M

So the question is how far should I push it? EGT is fine right now, it doesn't blow black smoke under load. I could turn up the fuel another 1/4 turn or just leave it alone.
So far I'm happy with the new power... However, I had the idea I should tune it just barely into opening the waste-gate under the highest load and leave it there.

Maybe I should just move on... paint the cowling, put all the new gauges in and get to the fun part of the project.

I plan to put an Arduino into it monitoring all the gauges, controlling the electric fan, and logging all the engine data to a USB stick. Once I get full instrumentation in (fuel out of tank and back to tank) I can calculate the engine efficiency rating on the fly and display on the Arduino's transreflective display.

 

[SPIKER]

Remember that black smoke is wasted fuel, so it is still clean burning which is good.

As for the waste gate those normally open when you get out of it and the turbo is spooled up, throttle blades close and that pop off opens to dump the pressure. That keeps the turbo pressure from blowing hoses and the like, it normally would not be used to control boost pressure unless it is the type w the boost regulator attached..


otherwise have fun sounds like it is working well, be careful as the gearing trans and axles etc are set up for 25~28HP not 35hp... I've twisted 2 axles off so far on Front end so easy to over stress them.

M

 

[ElectroTechnics]

I tried the tractor out on small tree's about 6' tall surrounding my brush pile. The turbo boost jumped to 4.5 PSI but the RPM barely dropped as it charged through.
I think I'm probably at the max boost I should push.... EGT did rise up to 620F while I was mowing those tree's

 

[sd455dan]

Sounds like you nailed it.
I agree with the idea that you won't see max boost until the engine sees a real world load for a at least a few seconds.

Good Job and a neat project

 

[amafrank]

Remember that black smoke is wasted fuel, so it is still clean burning which is good.

As for the waste gate those normally open when you get out of it and the turbo is spooled up, throttle blades close and that pop off opens to dump the pressure. That keeps the turbo pressure from blowing hoses and the like, it normally would not be used to control boost pressure unless it is the type w the boost regulator attached..
M

What throttle blades are you meaning? Diesels don't use a throttle as far as I know.....just the fuel control. I thought a wastegate dumped exhaust before the turbo to control boost. Am I missing something here?

Neat project. I talked about doing this many years ago to the Foton 254A but got hammered. Nice to see someone take the plunge and get it done.

Frank