Extreme Mechanic Solutions

24/04/2026

Engine: Iveco F3B Cursor 13
Problem: oil leak from the turbo charger on the inlet side.

In the air induction system the turbocharger is one of the most expensive parts so I usually treat it with caution . In most cases mechanics are quick to replace it , especially when there is a sign of oil in either the inlet or exhaust port or both.

In such cases I like to physically inspect the turbocharger, I check for shaft play, damaged blades any housing rubbing or blocked/ restricted return line. If those are clear then I am keeping on my turbo.
Now the question is why do we have oil in the inlet system. First you have to know how a turbocharger is built and how it works.
A turbocharger does not use rubber seals to seal in the lubrication oil. It uses metal piston rings, these rings don't seal in the oil 100%, so a differential pressure system comes in to help prevent the oil from leaking. Air pressure in the inlet pushes back the oil preventing it from seeping through the rings.
When this differential pressure system is unbalanced oil will sip through the rings into the inlet housing.
What can cause the differential pressure system to be unbalanced?

-blocked air filter
-exhaust air leak in the manifold between turbo and cylinder head
-resricted/ blocked turbo lubrication return line
- restricted or blocked breather
--malfunctioning pcv valve.

I checked the air filter I found it choked, the breather filter was also clogged. I opened the air inlet line to the cylinder head I found it with too much oil.

Action taken: changed air filter and breather filter then took out the after cooler to clean the oil which has accumulated in it.

NB- my supervisor had already brought a new turbocharger for replacement but the truck is back to work with the old turbocharger. Imagine after changing the turbo and the truck comes back with the same problem

30/03/2026

Perkins 1104D 44TA engine
Problem: low engine oil pressure
Observation: 0 bars reading on oil gauge

NB- recently received overhauled engine

In most cases we would jump for the pump . I remember my hydraulics lecturer at college, ' in a hydraulic system the pump does not create pressure, it creates flow , what creates pressure is restriction, then valves come in to regulate the system pressure according to system requirements'. More restriction more pressure, less restriction low pressure. The system is made to safeguard against extreme high pressure and low pressure by valves and/pressure sensors.
In the case of this engine,the oil pump incorporates a pressure regulator valve. When the pressure increases above the maximum set pressure this valve opens to redirect the oil back to the oil sump.
This valve fails in two ways, stuck open or stuck closed.
When stuck closed it elevates the system pressure above the normal working range which also has adverse effects on the engine. If it gets stuck open the oil pressure drops below the system range which also has adverse effects on the engine.
So before you remove the pump check the pressure regulator valve.
NB-On some engines this valve is found on different locations e.g. on the block.

27/03/2026

Engine: CAT C9
Problem: mixing ,engine oil into fuel

The fuel system used on this engine is HEUI system. On this fixed plant, we have 3 filter bases, the first being the water separator through which fuel flows from the tank to the transfer pump. the fuel transfer pump is connected in tandem(inline connected )with the high pressure injection pump. From the transfer pump the fuel passes through the primary and secondary filters into the fuel rail in the cylinder head. Along this fuel rail we got our unit injectors which are actuated by the pressurized engine oil from the injection pump. The residual fuel then flows out of the cylinder head to return to the tank. Adjacent to the fuel rail we also have an oil rail into which the injection pump sends engine oil under high pressure. When inserted into the cylinder head the unit injectors will cut across both the oil and fuel rails, so to prevent mixing the injectors are mounted with O ring seal.

Objective: find out where the oil is mixing with the fuel.
- where on the engine does engine oil get closer to the fuel system with the possibility of mixing

Findings:
1-injection pump/transfer pump
2-oil rail/fuel rail
3-on the injectors( O rings separating fuel and oil galleries)

Elimination of possible causes to narrow down to the course

At this point the fuel in the filters has turned dark because of bent oil going into the fuel.

Steps-

-remove all fuel filters , drain them and clean out the dirty fuel with clean diesel
-remove fuel from the fuel lines
-find a clean contain with clean diesel
-re install the filters remove the suction line and put in the container with clean diesel and bleed the fuel system ( leave the return line connected to the main tank.
-run the engine for 15 to 20 minutes.
-stop the engine and remove the water separator filter pour out the diesel and observe the colour
-do the same with primary and secondary filter

Possible outcomes

-fuel in primary and secondary filter clean
-fuel in the primary and secondary filters dirty

Interpretation

Dirty fuel in filters- this means contamination is happening before the fuel reaches the cylinder head
Clean fuel filters (primary/secondary)- this means contamination is happening with the block.

Conclusion:
-if the fuel in the filters is found to be clean the problem is within the cylinder head ,across rails( crack in the head) or across O ring seals at the injectors
- if the fuel in the filters had darkened the problem might be contamination and the injection pump/ transfer pump assembly.

PS- WITH THIS ENGINE OIL WAS BYPASSING FROM THE INJECTION PUMP INTO THE TRANSFER PUMP, I REMOVED THE TRANSFER PUMP AND FITTED ANOTHER

NB- ON THIS ENGINE DO NOT REMOVE THE TRANSFER PUMP IF YOU DON'T KNOW THE PROCEDURE
My next post will be on the procedure to remove the transfer pump

22/02/2026

Toyota Voxy

Problem very high idling rpm 1500rpm + and stalling sometimes

Checked PCV valve , damaged intake line, malfunctioning EGRV, damaged brake assist(vacuum) all was good.

Here is how your car works, besides your input through the accelerator your car depends on sensors to determine the amount of fuel to deliver to the injector,these are MAP, MAF, IAT , coolant temperature sensors, etc.

The engine works best when it acquires the normal working temperature, this temperature is detected through the coolant temperature sensor. So to achieve that temperature quickly the ECM is programmed to accelerate the engine to a predetermined rpm mostly 1500rpm so that it quickly attains the working temperature after which the engine rpm automatically declines to between 500 and 1000 rpm in idling.

Therefore if the temperature sensor is not working properly there is no way for the ECM to know the temperature of the coolant hence it will keep the engine continuously running at 1500rpm.

The best way to solve this issue is with a diagnostic
machine as it will take you to the exact problem without wasting more time. From the diagnostic I searched for fault codes and found two codes,one for the IAT and the other for the coolant sensors . Sensors exhibit different times of problems so to verify I had to open the data stream for the engine ECM. I selected IAT and coolant sensors and both sensors returned -40° F , which is a default temperature when there is total signal failure from the two temperature sensors.

To confirm that the vehicle was getting stuck in the warming up phase at 1500 rpm , I had to do another check, on data stream I checked for idle signal(IDL SIG). After running the engine for a long time it remained on OFF,meaning the ECM wasn't commanding the system to go to idle.

So now the information was clear, the car was getting stuck in the warm up phase at higher rpm because the ECM wasn't getting the required signal from the temperature sensor so process as idle on(IDL ON) signal which will return the engine to low idle rpm.

After thorough checking, found the problem to have been an open circuit on bought sensors, fixed the wiring and the idling is now at 500-700rpm

21/01/2026

A client brings a car/ machine with problem of oil from the exhaust or inlet system. After diagnosis you request the client to buy a turbocharger but after installing the new turbocharger you still have the same problem . Where did you go wrong?

First you need to understand how a turbocharger functions and how the turbocharger was designed.
The oil passes through the turbocharger for lubrication and cooling purposes . There are some holes directing the oil to the shaft connecting the impeller and the turbine. At the end of each side of the shaft just behind either the impeller or turbine there are 'piston rings like seals(metallic) . These seals are to prevent the oil seeping out on the shaft ends, because they are metallic they don't provide a perfect seal meaning oil can seep through.

Then what prevents the oil from leaking and the turbocharger is working? On the inlet side is the pressure of the incoming air and on the exhaust side is the pressure of the exhaust gas. Pressure difference between the oil pressure in the turbocharger and the pressure of the inlet/exhaust gases is used to supplement the poor sealing quality ot the metallic seals.

So irregularities that will offset the pressure difference within the turbocharger will cause it to leak oil e.g, blocked air filter, leaking exhaust manifold, blocked turbocharger oil return line, blocked crankcase ventilation system etc.

A GOOD MECHANIC IS THE ONE WHO GETS THE JOB DONE WITH THE LEAST POSSIBLE COSTS

22/12/2025

Fixed plant mechanic, it doesn't matter which engine brand, we fix

22/12/2025

14/12/2025

..game over..

29/09/2025

Battery health testing. There are four things to check out when testing battery health, voltage, internal resistance, SOC, SOH and CCA.

CCA - cold cranking amps-CCA is the number of amps a 12-volt battery can provide for 30 seconds at 0°F (-18°C) while maintaining a minimum voltage of 7.2 volts. NB batteries have different CCA according to size and the CCA is a specific to a type of battery

SOC-state of charge- a percentage indicating the remaining energy in the battery

SOH-state of health - current battery health compared to when it was new

Internal resistance-its own electrical resistance, which hinders current flow and is a key indicator of its health and ability to provide high-current starting power (CCA).

This battery that was tested here has a CCA of 725, compared to the 304 on the tester, it could even crank the engine

15/09/2025

I got a P0192 fault code, "Fuel Rail Pressure Sensor 'A' Circuit Low". the engine is running rough and stalling sometimes.
Using my diagnostic I found the fuel pressure to be around 820 psi , the range for the pressure should be 1800-1900 psi.
The cause for this can be the following
1-faulty low fuel pressure pump
2-very low fuel causing air to be sucked into the fuel system
3-clogged fuel filter
4-obstructed fuel lines
5-faulty high pressure fuel pump
6-faulty high pressure sensor
7- problem with high pressure sensor wiring
8-faulty PCM.
9-faulty pressure regulator valve
The fuel system has both low pressure and high pressure sensors. Using that I can eliminate other possible causes from the list. Faults 1 -3 can cause low pressure in the low pressure fuel system. Fault 4 can cause low pressure in either low or high pressure systems depending on the position of the obstruction. NB any of the above faults will subsequently lead to low pressure in the high pressure system but faults 1-4 will trigger another code related to the low pressure system so most likely you will have a P0087/P008A code to accompany the P0192 code.
So with the information I got I will concentrate on 4-9 as I only have one fault code, P0192.
To further eliminate other possible causes I would use a manual gauge. If the gauge results shows normal pressure I would eliminate all except 6,7 and 8 from the possible causes, but if the pressure
on the gauge is low, then 5 and 9 can be the causes.
If I get the honour to repair your car, this is how I will do it, I won't throw parts at it and hope for the best. Extreme Mechanic Solutions is the game