[Jaggu]

Blocked fuel lines leading to pressure loss at injectors, and old injector also is not rectifying the issue right? Issue is different. And hence a stupid suggestion ^^

[Sudarshan]

^^ Specially the old Hi pressure lines from an engine which has been sitting unused for a long time , they cause trouble when they come in use . Small particles get loose & disturb the function of injectors ( rust etc )

I have tried the carburator cleaning spray successfully before for this purpose ( cleaning ) , but next time I am going to try something different like getting it cleaned & treated from a plating guy .

Sudarshan

[Sutripta]

Originally Posted by Jaggu

Stroke of the engine, Discussion needed!
flywheel weight etc also right? No

Regards
Sutripta

[drjones]

1. Not much in fuel lines, cause, if you see in the picture, the fuel line is just a tin with a rubber tube connected.
2. With the old injectors, the problem is not present.
3. Both the nozzles were checked for spray in the pressure checking machine.
Thanks.

[DirtyDan]

Originally Posted by drjones

1. Not much in fuel lines, cause, if you see in the picture, the fuel line is just a tin with a rubber tube connected.
2. With the old injectors, the problem is not present.
3. Both the nozzles were checked for spray in the pressure checking machine.
Thanks.

The old injectors test okay in the lab.
The new injectors test okay in the lab.

The old injectors work in the motor.
The new injectors malfunction in the motor.

Right?

Hence,

1.) the old and new injectors do not have the same spec regardless of what the book says...

and/or,

2.) the lab test is wrong.

or, for some reason,

3.) the install of the new injector(s) is not done right


What else can we correct or add to this?





..

[headers]

Recheck new injectors?
Re.instal , re bleed all fuel lines and remove air trapped in the system.
Change another set of injectors.

[DirtyDan]

Change to another set of new injectors gets my vote. Okay, Doc, Headers and I agree so that is probably the kiss of death....buy a Thar.

[headers]

Originally Posted by DirtyDan

Change to another set of new injectors gets my vote. Okay, Doc, Headers and I agree so that is probably the kiss of death....buy a Thar.

Rofl..that was my first suggestion.

Btw, doc is mighty impressed with the thar crde, owned by a common friend.

Maybe I'll pick one too, but the elusive factory fitted AC keeps me waiting.

[Sudarshan]

Originally Posted by DirtyDan

What else can we correct or add to this?

.

Fiddle with pump timing might help , Advance reduces smoke but little rattle , retard little more smoke but smooth

choosing a right spot is

Sudarshan

[Frankenstein]

Originally Posted by ex670c

Hi Sandeep,

What are the factors affecting power output ?

Torque & RPM

Torque will be dependent on the Displacement & Fueling.

RPM is dependent on the inherent engine design.

So considering an XD3P is 2498cc & SD25 is 2488cc, how much more power do you think the SD25 can generate(without Turbo-Charging)

They won't be generating more than 15-17Kgm MAX RPM

Are you suggesting that the SD25 generates 20-25Kgm torque?

Lets calculate the effect of Gearing. IIRC SD25 generates 16.5Kgm

1) 3.986 X 2.46 X 5.38 X 15.5Kgm (XD3P) = 52.75 X 15.5Kgm = 817.6Kgm

2) 3.986 X 2.46 X 4.88 X 16.5Kgm (SD25) = 47.8 X 16.5Kgm = 789Kgm

3) 3.986 X 2.46 X 4.27 X 16.5 (SD25) = 41.86 X 16.5Kgm = 690.8Kgm

wrt to weighing the SD25 & XD3P I have pulled and lifted a few engines, I felt the SD25 was considerably heavier.

wrt 51" CKKP vs 57" OKBJ there are many advantages
1) Better Turning Radius
2) Stronger Axles
3) Trouble Free Knuckles
4) Uprated TREs

Regards,

Arka

Arka nice maths, infact very true .
But are you sure the xd3p generates 15.5 kgm torque, i am not questioning your experience but the source, if it does then why is it soo sluggish compared to the sd25 and Isuzu G1.
So even with 4.88 sd25 generates almost equal torque of a xd3p with 5.38 just 2 % less.
The xd3p all said and done has issues, heating problem being the first. SD25 has no heating issues, it was used in load carrying vehicles as well as marine.Xd3p on the other hand loses steam if it encounters an incline.

The kiki pump has a load governor and i am sure you know the benefit .
I dont think Xd3p generates 15.5kgm, and to top it , sd25 in stock is very good, you can still play with the pump setting.

No point having an argument , let Jonathan complete his transplant and we can hear the results from him.

[drjones]

Dirty Dan - You are correct, spot on. Specs might be different than in their Bosch catalog, but, how to go about it? Lab test was done meticulously. Two sets of new injectors, rechecked and fixed too.
Headers - Done that too.
Sudarshan - Timing was completely redone 7 times with all possible settings. Plonk the old injectors, problem just disappears.

So, we are left with the catalog being wrong and the Thar's kiss of death. Can I just drop this for now, fix the engine as it is, run it for few hours, set it, rearrange the air intake, exhaust, check for the front shaft clearance, then finally take it to chennai Bosch service center and try again? If so, which is the best Bosch service center in Chennai?

[ex670c]

Originally Posted by Frankenstein

Arka nice maths, infact very true .
But are you sure the xd3p generates 15.5 kgm torque, i am not questioning your experience but the source, if it does then why is it soo sluggish compared to the sd25 and Isuzu G1.
So even with 4.88 sd25 generates almost equal torque of a xd3p with 5.38 just 2 % less.
The xd3p all said and done has issues, heating problem being the first. SD25 has no heating issues, it was used in load carrying vehicles as well as marine.Xd3p on the other hand loses steam if it encounters an incline.

The kiki pump has a load governor and i am sure you know the benefit .
I dont think Xd3p generates 15.5kgm, and to top it , sd25 in stock is very good, you can still play with the pump setting.

No point having an argument , let Jonathan complete his transplant and we can hear the results from him.

Hi Sandeep,

Good you took your time understanding the Maths.

I have enough sources from the M&M XD3P service manual to the XD3P FIP manuals stating 15.3 - 15.5Kgm, only the BS3 XD3PU genrate 13.5Kgm as it is de-tuned for emission reasons.

wrt to the maths it is 3.5% lesser torque than a XD3P, and that is enough to make a difference on climbs, especially sandy climbs.

wrt to heating issues, it has to do with the engine install and correct cooling system, over-heating is mainly caused in XD series engine which run with out thermostat.

Regards

Arka

[headers]

Doc, Pl contact Star_aqua immediately. He works for Bosch and may be able to guide you.

[ex670c]

Originally Posted by drjones

Dirty Dan - You are correct, spot on. Specs might be different than in their Bosch catalog, but, how to go about it? Lab test was done meticulously. Two sets of new injectors, rechecked and fixed too.
Headers - Done that too.
Sudarshan - Timing was completely redone 7 times with all possible settings. Plonk the old injectors, problem just disappears.

So, we are left with the catalog being wrong and the Thar's kiss of death. Can I just drop this for now, fix the engine as it is, run it for few hours, set it, rearrange the air intake, exhaust, check for the front shaft clearance, then finally take it to chennai Bosch service center and try again? If so, which is the best Bosch service center in Chennai?

Hi Dr. Jones,

Was the FIP fitted keeping the Pump Timing and Orientation in mind.

Do the Timing Chain/Gears have play.

What about Valve Timing/Tappet Adjustment?

Regards,

Arka

[drjones]

Originally Posted by ex670c

Hi Dr. Jones,

Was the FIP fitted keeping the Pump Timing and Orientation in mind.

Do the Timing Chain/Gears have play.

What about Valve Timing/Tappet Adjustment?

Regards,

Arka

Arka, all those things are fine, but, should everything become absolutely normal with the old injectors with the same settings?