What is the Volvo TAMD61A injection pump (Bosch PE6P110A320RS499) maximum pressure?

[Lucas Gan]

Does anyone know what the maximum pressure the injection pump in the Volvo TAMD61A engine can provide? Or do you know what the model of this injection pump is? I only know it's a Bosch pump, but the model number can't be read because it's covered by the previous paint.

I am thinking of replacing the injector nozzle with a different model which requires a minimum pressure of 270 bar (3916 psi). The original nozzle is at 255 bar (3698 psi).

The original nozzle is 4 holes, and the intended new one is 5 holes. It's an experiment. Let me know if you have any ideas. Thanks

EDITED: I have found the pump model is Bosch PE6P110A320RS499

 

[Boat2016]

Is anyone know what is the maximum pressure the injection pump in Volvo TAMD61A engine can provide? Or, do you know what model of this injection pump is? I only know it's a Bosch pump, but the model number can't be read because it's covered by the previous paint.

I am thinking to replace the injectors nozzle to a different model which is required minimum pressure 270 bar (3916 psi). The original nozzle is at 255 bar (3698 psi).

The original nozzle is 4 holes, the intention new one is 5 holes. It's an experiment. Let me know if you have any idea. Thanks

What are you trying to achieve ?

Something as critical as an injector would be the last thing I would mess with having witnessed the damage it can do to your engine, those kind of tasks are best left to the professionals.

 

[Lucas Gan]

An experiment to reduce the unburnt fuel becomes smoke.

Last year, I experimented with replacing the same pressure nozzle with a much larger hole. The result was more unburnt fuel became more smoke. So, this year I am going to get a smaller hole nozzle to try and see if the reduction of hole size will reduce the smoke or not. The idea is simply to reduce the fuel amount and improve the atomization by changing the nozzle.

Now the only problem is that the new nozzle I am looking for requires higher pressure. It said 270-282 bars on the Bosch manual. So, if the injection pump can support this pressure that will be no problem to try. Do let me know if anyone knows the data of the injection pump. Thank you.

I know that sounds scary to most people. But I feel ok to do the experiment. To reduce the nozzle hole, the worst case is the engine won't start or low rev. Then I can always change back to the original one as I did last year.

 

[Boat2016]

An experiment to reduce the unburnt fuel becomes smoke.

Last year, I experimented with replacing the same pressure nozzle with a much larger hole. The result was more unburnt fuel became more smoke. So, this year I am going to get a smaller hole nozzle to try and see if the reduction of hole size will reduce the smoke or not. The idea is simply to reduce the fuel amount and improve the atomization by changing the nozzle.

Now the only problem is that the new nozzle I am looking for requires higher pressure. It said 270-282 bars on the Bosch manual. So, if the injection pump can support this pressure that will be no problem to try. Do let me know if anyone knows the data of the injection pump. Thank you.

I know that sounds scary to most people. But I feel ok to do the experiment. To reduce the nozzle hole, the worst case is the engine won't start or low rev. Then I can always change back to the original one as I did last year.

Hope the experiment is a success and whatever way it goes looking forward to reading the results

 

[volvopaul]

Is anyone know what is the maximum pressure the injection pump in Volvo TAMD61A engine can provide? Or, do you know what model of this injection pump is? I only know it's a Bosch pump, but the model number can't be read because it's covered by the previous paint.

I am thinking to replace the injectors nozzle to a different model which is required minimum pressure 270 bar (3916 psi). The original nozzle is at 255 bar (3698 psi).

The original nozzle is 4 holes, the intention new one is 5 holes. It's an experiment. Let me know if you have any idea. Thanks

I’d guess you’re thinking of using the nozzles from the 75 p as it’s a 5 nozzle unit , I’d think that the piston design is different, what are you looking to achieve ? I’d think less smoke on start up .

 

[Bilgediver]

In a standard system the pump delivers precise volumes and so the pressure is dependent don't on the area of the sum of the injector holes. Make holes smaller pressure goes up. Make holes larger pressure goes down and injection is lower quality. Take note of the experience of an earlier poster who discovered this to be the case.

In a common rail system the injection is electronically timed so the amount delivered would vary according to the variation nozzle size as the fuel is available at constant pressure .Changing nozzle size could result in poor combustion conditions.

 

[Lucas Gan]

@volvopaul It's not the one I am looking for. I am looking for one with the same angle but 5 smaller holes. Thus, the amount of fuel delivered to the chamber will be less, and the atomization should be better I think.

@Bilgediver Thank you for the information. The new nozzle opening pressure will be at least 270 bars while the original nozzle opening pressure is 255 bars. So I just need to make sure the pump is capable of holding the pressure at least 270 bars without damaging itself in the long term.

 

[QBhoy]

Can’t deny, I’m interested to read how you get on…but also happen to know, that depending on what you’re trying to achieve here…there might be other things better looked at. I’ve looked after a pair of these meticulously, for about 17 years now.
Just simply overhauling/exchanging the standard injectors every 500 hours or 4/5 years…makes a huge difference.
Making certain the turbo is in good health and tolerances are in spec each end…also proves time well spent and ideal running health.
Crank case breather filter vent units changed every year
Clean fuel supply, unrestricted too
Oil change every year or 100 hours (whichever comes first) with mineral 15w40 makes a huge difference to her health and compression figures.
Arguably there is reason behind the idea around replacing the rather restrictive standard air filtration arrangement, for something less asthmatic.
Perhaps as important as each of the above..but often overlooked…is making certain, she is able to operate at the correct temperature. Stuck open thermostats and running cold, is often an ignored thing, all too often. If she’s not at temperature and ideal operating conditions, she will loose compression, power and the ability to see an efficient combustion. Followed by throwing fuel into the oil…worsening the situation further, not to mention long term irreversible damage.
Anyway. I could go on…you get the point though. Best of luck !

 

[Lucas Gan]

Ok. I found my injection pump model now. It's a Bosch PE6P110A320RS499. Just cannot find a manual or a datasheet. Please let me know if you have any ideas. Many thanks.

 

[rotrax]

I have some small experience of Bosch rotary pumps. AFAIK most have a primary regulator valve that can be adjusted.

You MIGHT find a specialist who can or is prepared to adjust your pump pressure.

Chris at CJ Diesel Repair in Sunbury might advise.

He has just done our pump and fitted new injector nozzles.

Not cheap, but on time, price as quoted and engine now working beautifully.

 

[Lucas Gan]

Thank you guys.

I will just put the new nozzle to have a simple try and see what happens. Since the pump is an old-model mechanical pump. It has no EDU, ECU or electric control unit whatsoever. I think the only part to control the maximum pressure is a pressure relief valve inside the pump. So if I simply put the new nozzle on, there will be two possible results:

1. The nozzle won't open, engine won't start. If the nozzle opening pressure is greater than the pump pressure relief valve holding pressure, the valve should open and relieve the fuel, so the fuel pressure drops, then the nozzle won't open.

2. Working as normal if the pump pressure relief valve holding pressure is greater than the nozzle opening pressure.

I can't think of other situations. So I think it's no harm to give it a try.

Please correct me if I am wrong. Thank you.

 

[Bilgediver]

Thank you guys.

I will just put the new nozzle to have a simple try and see what happens. Since the pump is an old-model mechanical pump. It has no EDU, ECU or electric control unit whatsoever. I think the only part to control the maximum pressure is a pressure relief valve inside the pump. So if I simply put the new nozzle on, there will be two possible results:

1. The nozzle won't open, engine won't start. If the nozzle opening pressure is greater than the pump pressure relief valve holding pressure, the valve should open and relieve the fuel, so the fuel pressure drops, then the nozzle won't open.

2. Working as normal if the pump pressure relief valve holding pressure is greater than the nozzle opening pressure.

I can't think of other situations. So I think it's no harm to give it a try.

Please correct me if I am wrong. Thank you.

You have a plunger type fuel pump with separate pump elements for each cylinder. These pumps are engineered to deliver a fixed volume each stroke the amount depending the fuel setting set by the governor this fuel is delivered to the injector nozzle and the only device holding the fuel to a pre-set pressure is the injector opening setting and during delivery the injector port size. If you make the area of the ports a different size then I would suggest you get an endoscope and monitor the condition of the pistons Look for signs of burning or other damage once you begin your tests . The injection conditions and piston/head profiles are engineered to match the injector spray pattern so any changes in spray pattern could damage piston or head.
Note that the pressure in the pump is NOT controlled by relief valves or other devices but arrived at by the design of the pump and matching injector. Reduce the injector port area and pressure rises. Increase port area and pressure reduces if no changes made to fuel pump.

 

[Lucas Gan]

Thank you @Bilgediver I have two questions :

1. Assuming the pump pressure high enough to make the nozzle open. Is it possible if the fuel volume exceeds the nozzle hole area, then the extra fuel goes out to the injector return hole and returns to the tank?

2. Assuming the pump pressure is NOT high enough to make the nozzle open.As you said, if the only device holding the fuel to a pre-set pressure is the injector opening set. Then maybe the real trouble is that the fuel goes nowhere but overpressing inside the pump, which may damage the pump.

 

[DownWest]

I am a bit late here, but this thread was linked to another. I suspect both your 1 & 2 are incorrect. The pump, in good condition, will easily open the injector, set at a higher pressure, the % increase is not much. The holes are more about distribution in the cylinder.
As said, fiddling with the manfacturers ideas is likely not a good idea, but making sure everything is in good condition and set to original points is.

 

[Bilgediver]

Thank you @Bilgediver I have two questions :

1. Assuming the pump pressure high enough to make the nozzle open. Is it possible if the fuel volume exceeds the nozzle hole area, then the extra fuel goes out to the injector return hole and returns to the tank?

2. Assuming the pump pressure is NOT high enough to make the nozzle open.As you said, if the only device holding the fuel to a pre-set pressure is the injector opening set. Then maybe the real trouble is that the fuel goes nowhere but overpressing inside the pump, which may damage the pump.

The injector design is such that it is matched to the volumes of fuel delivered the pump The pump is a variable delivery pump and as more fuel is delivered to the cylinder more power is developed.

The leakage is minimal and would not vary very much with changes of pressure.

The injector design regarding the number and size of the ports is important as if the pump develops more pressure due to missmatch brout about buy deli ering too much fuel then ther is the danger of burning components in the cylinde

I very much doubt if any tweeks, you make will give any benefits as the characteristics of the pumps and injector nozzles will have been carefully selected to be correct for the cylinder dimensions so that no flame damage is caused.

 

[QBhoy]

Thank you guys.

I will just put the new nozzle to have a simple try and see what happens. Since the pump is an old-model mechanical pump. It has no EDU, ECU or electric control unit whatsoever. I think the only part to control the maximum pressure is a pressure relief valve inside the pump. So if I simply put the new nozzle on, there will be two possible results:

1. The nozzle won't open, engine won't start. If the nozzle opening pressure is greater than the pump pressure relief valve holding pressure, the valve should open and relieve the fuel, so the fuel pressure drops, then the nozzle won't open.

2. Working as normal if the pump pressure relief valve holding pressure is greater than the nozzle opening pressure.

I can't think of other situations. So I think it's no harm to give it a try.

Please correct me if I am wrong. Thank you.

Not sure if it’s been mentioned already…perhaps it has…but on occasion, the nozzle set up and/or spray pattern, can be quite deliberate, to suit the piston crown..or at least with a specific combustion condition in mind. A change in spray pattern, may not be optimal in some cases. Must admit though…I couldn’t say for sure if this might apply here. Keep us updated for sure.

 

[Lucas Gan]

It's good to learn that from you guys. Thanks.
I will arrange a time to do the experiment and let you guys know the outcome.