Combustion Engine Repairs
Diesel engine overhauls are one of WIBAKO's core specialisms. We repair engines from construction and industrial machinery, from diagnostics and inspection, through the full rebuild of combustion engines, to load testing on our dynamometer. We also provide on-site engine service and supply ready-to-fit exchange units to keep machine downtime to a minimum.
Contact us about an engine overhaul: phone +48 33 870 42 00, WhatsApp +48 532 161 000, e-mail biuro@wibako.pl. You can also use our contact form.
Why entrust your engine overhaul to us
Technical facilities. We have diagnostic bays, specialist measuring equipment and our own engine dynamometer. This means every engine is tested under load, not just at idle.
Experienced team. Our mechanics have rebuilt Liebherr, Cummins, Deutz, Perkins, Volvo, Caterpillar, Komatsu, Iveco, Mercedes engines and units from many other manufacturers. Every repair starts with a thorough inspection of the engine's condition, because only on that basis can a durable overhaul be planned, rather than a quick patch-up.
Scope of an engine overhaul
During an overhaul we inspect and recondition all the components that determine compression, lubrication and combustion. Wear parts, i.e. bearing shells, piston rings and seals, are always replaced with new ones.
Block and cylinder liners
We measure bore ovality and taper, and check the block deck and liner seats. Worn liners or liners with cavitation pitting are replaced, while bores in linerless blocks are honed or rebored to oversize.
Cylinder head
We resurface the head, recondition the valve seats and replace the valve guides. Pressure testing reveals cracks between the valve seats, which are the most common cause of coolant loss and white smoke.
Crankshaft and bearings
We measure the main and crankpin journals. The crankshaft can be reground to undersize and fitted with matching bearing shells. Read more in our article crankshaft and bearings – damage and reconditioning.
Pistons and connecting rods
We check the pistons, ring grooves, gudgeon pins as well as connecting rod straightness and bores (details in the article piston and connecting rod in a diesel engine).
Fuel injection system
Injectors and injection pumps are tested, then reconditioned or replaced. Injectors with a poor spray pattern can destroy the pistons of a freshly rebuilt engine in a short time.
Turbocharger
We check the axial and radial play of the rotor, the bearing condition and the seals. Depending on its condition, the turbocharger is rebuilt or replaced.
Ancillaries
We replace or recondition the oil pump and water pump, oil cooler, thermostats, timing gear and camshaft.
How an overhaul works: diagnostics, quote, rebuild
- Inspection and diagnostics. The engine is fully stripped and each part is assessed for wear and compliance with factory specifications. We determine what can be reconditioned and what needs replacing.
- Individual quote. It takes into account the engine type and model, degree of wear, operating history and the scope of work required. Work begins only once the quote has been approved.
- Rebuild and assembly. The engine is assembled to the manufacturer's specification: clearances, tightening torques and assembly sequence.
- Documentation. Every stage is photographed, so the customer can follow progress and see the condition of parts before replacement.
- Dynamometer testing before the engine is released.
If the quote does not suit the customer, they can decide not to proceed with the overhaul.
Engine dynamometer testing
At the heart of our test bench is a water brake connected to the engine flywheel by a cardan shaft. This allows smooth load control and measurement of power and torque without the losses caused in the machine by the hydraulics and drivetrain.
After the overhaul, the engine is first run in at around 20–30% load for several to a dozen or so hours, so that the rings and bearings bed in properly. We then plot the power and torque curves across different rpm ranges. Finally, the engine runs for 2–3 hours at around 50% load, simulating typical operation. During this we check:
- the tightness of all systems,
- oil pressure and temperatures across different operating ranges,
- boost pressure and crankcase blow-by,
- speed stability, power, torque and fuel consumption.
We have described such a test using an engine from a mobile crane as an example: dyno testing and first start-up after overhaul – Liebherr LTM 1080.
Major overhaul of a diesel engine – what it involves
A major overhaul is a complete rebuild of the power unit, aimed at restoring performance close to factory specifications. It is carried out in cases of severe wear, seizure, loss of power, excessive oil consumption or failure of key components.
The process includes complete disassembly, inspection of the block, cylinder head, crankshaft, camshaft, pistons and liners, reconditioning or replacement of parts, assembly to the manufacturer's specification and a dynamometer test.
A properly performed major overhaul significantly extends engine life: the unit starts its next service cycle with new friction components and correct clearances. It also reduces the risk of further failures and allows the machine to return to intensive work in harsh conditions. Where the block or crankshaft cannot be reconditioned, replacing it with a used or rebuilt engine is often the more cost-effective option.
Engine makes and models we service
- Liebherr – D924, D926, D934, D936, D946, D9406, D9508
- Cummins – QSB4.5, QSB6.7, QSC8.3
- Deutz – BF4M1012, BF6M1013, TCD2013 L06, TCD 4.1, TCD 6.1
- Volvo – D7D, D7E, D12
- John Deere – 4045, 6068
- Perkins – 1106
- Mercedes – OM906
- Caterpillar, Komatsu, Iveco, Kubota
Industrial engines, generator sets and special machinery
In addition to excavators, loaders and dozers, we service industrial engines in special machinery: screeners, crushers, wood chippers, combine harvesters, rollers, asphalt pavers and mobile cranes. Industrial engine repairs follow the same process as for construction machinery: inspection, overhaul and dynamometer testing.
Mobile service – removal and installation on site
Our service vehicles carry diagnostic equipment and tools for mechanical and hydraulic repairs. We travel to customers throughout Poland: we diagnose the fault on site and, if the overhaul requires a workshop, we remove the engine and refit it after the repair. Our headquarters are in Kojszówka, so diesel engine repairs in the Lesser Poland region and around Kraków are part of our everyday work.
Mechanic's hourly rate: PLN 230 net (per mechanic). When fitting parts purchased from WIBAKO: PLN 190 net. Travel: PLN 3 net per km, charged both ways.
Signs that your engine needs repair
- white, blue or black smoke,
- excessive oil consumption between changes,
- oil in the coolant or coolant in the oil,
- low oil pressure or the warning light coming on,
- knocking and metallic noises (bearings, valves, timing gear),
- hard starting when cold or hot,
- loss of power under load and slower working movements,
- rough running, hunting rpm, vibration,
- engine overheating.
Why early diagnostics pays off: at the onset of a fault, the repair is usually limited to the injectors, turbocharger or seals. Continued operation damages the cylinder bores and crankshaft, and metal debris can spread further. See what computer diagnostics of construction machinery engines looks like.
Warranty
We provide a 12-month warranty on all work carried out. Detailed terms are agreed when the order is accepted.
How long does an engine overhaul take
An overhaul usually takes from a few days to several weeks, depending on the engine type, extent of damage and parts availability. For popular engines an exchange unit can be used, which significantly reduces machine downtime.
How much does an engine overhaul cost – quotation
The cost depends on the model, design, operating hours and extent of damage. We prepare a reliable quote after disassembly and measurements. Send us the engine model, serial number and a description of the symptoms via the form or e-mail, and we will outline the next steps.
Engine parts and components – availability and quality
We keep an extensive stock of diesel engine parts, which shortens repair times. We offer:
- new, used and remanufactured parts, both OEM and good-quality aftermarket replacements,
- components checked and selected by our specialists,
- support from technical advisers in choosing parts compatible with your engine.
New, used and rebuilt engines
Alongside our service work, we sell complete power units: brand new, used and rebuilt. Every engine is dyno tested before release.
Once mounted on the test bench, a used engine is warmed up to operating temperature, after which we check its power, torque and running at medium load. This shows whether it is fit for further use.
Our projects
Examples of our work:
- Komatsu PC350LC – engine replacement with a converted Cummins QSC8.3
- assembling a Liebherr D9406 engine after block reconditioning
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#1.Where to start?
The first step is to contact Łukasz, our coordinator for internal combustion engine repairs. You can call +48 33 870 42 15 or use the contact form available on our website.
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#2.How to deliver a combustion engine for repair?
You have several convenient options to choose from:
- Personal delivery to our workshop.
- Sending the engine by courier.
- We can also arrange for a courier to ship the engine on a pallet from a specified location, and after the repair service is completed, the courier will deliver it back.
- If you lack the appropriate facilities for disassembly or assembly, our mobile service can come to you and perform these services on-site. -
#3.How does the engine repair process proceed?
Our engine overhaul process is thorough and transparent:
- Detailed verification: the engine is disassembled down to the "last screw" and subjected to a detailed verification.
- Cost estimate and schedule: we prepare a comprehensive cost estimate and determine the expected repair time.
- Major overhaul: upon your acceptance of the terms, we proceed with a comprehensive repair, which is always a major overhaul, not just a replacement of individual components.
- Testing and painting: The overhaul is completed when the engine successfully passes tests at the engine dynamometer station. The final stage is professional engine painting. -
#4.What will you find in our offer?
We always strive to present you with the most beneficial solutions, therefore depending on the availability of spare parts you will receive:
- An estimate for repair with original parts.
- An estimate for repair with high-quality spare parts.
- As an alternative, we can propose purchasing the same refurbished engine from our warehouse, which often significantly shortens the completion time. -
#5.How long does it take to repair a combustion engine?
- The verification of your engine will take us 1-3 days from the moment of delivery.
- You will receive an estimate for typical repairs within the next business day after the verification is completed.
- The repair itself usually takes about 3-5 weeks. -
#6.How do we test combustion engines?
Every refurbished engine undergoes rigorous testing on our engine dynamometer. The unit is loaded in a way that simulates operation in a construction machine. During the tests, we check key parameters such as:
- Power and torque performance.
- Coolant and oil temperature.
- Oil pressure depending on its temperature.
- Behavior and performance changes in relation to load.
The entire test lasts on average from 12 to 24 hours, depending on the specifics of the engine. -
#7.How can I be sure that the engine will work after the repair?
We care about the highest quality:
- We perform repairs exclusively on high-quality parts, and assembly work is always in accordance with the specification of a given engine.
- After the repair, the engine is thoroughly tested. The test result is always available in the form of a readable chart.
- You will receive a 12-month warranty for each repair. In case of questions regarding assembly or operation, we encourage you to use the expert knowledge of our sales advisors through a phone call. -
#8.Can I cancel the repair after receiving the estimate?
Yes, you can cancel the repair without any costs after receiving the estimate and before accepting it.
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#9.How much does it cost to repair my engine?
The cost of repair depends on several factors: the engine model, the degree of its wear and tear, and the scale of damage. Very often we can only provide an approximate price range, based on our history of similar repairs.
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#10.Do you overhaul industrial and special-machinery engines?
Yes, we overhaul combustion engines for construction, industrial and special machinery. Write to us via the contact form.
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#11.Is an exchange engine possible?
If we have the same overhauled engine in stock, we can offer it as an alternative, which often significantly shortens the lead time. Write to us via the contact form.
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#12.Do you remove the engine at the customer's site?
Yes, our mobile service can come to you and perform the engine removal and installation on-site. Write to us via the contact form.
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#13.What does the warranty after overhaul look like?
Every engine overhaul comes with a 12-month warranty, and the engine is tested on the dynamometer after the work. Write to us via the contact form.
Frequently asked questions
How much does it cost to overhaul a construction machinery engine?
The cost depends on the engine model, operating hours, technical condition and extent of damage. We prepare an accurate quote after disassembly and inspection of the parts, and work begins only once the quote has been approved. If the quote does not suit the customer, they can decide not to proceed with the overhaul.
How long does a major overhaul of a diesel engine take?
Usually from a few days to several weeks, depending on the engine type, parts availability and scope of work. For popular engines an exchange unit can be used, which significantly reduces machine downtime.
Is the engine tested on a dynamometer after the overhaul?
Yes. After assembly, the engine is run in under light load, and then we check its power, torque, oil pressure, temperatures and tightness. Any faults found on the dyno are fixed before the engine is installed in the machine.
Which engine makes do you overhaul?
We most often overhaul Liebherr, Cummins, Deutz, Volvo, Perkins, Caterpillar, Komatsu, Iveco, Mercedes, John Deere and Kubota engines. For other engines, please contact us and provide the engine model.
Can you remove the engine from a machine on a construction site?
Yes. Our mobile service travels to customers throughout Poland, carries out on-site diagnostics and removes and installs engines or ancillary components.
What warranty do you give on an engine overhaul?
We provide a 12-month warranty on the work carried out. Detailed terms depend on the scope of the order and are agreed when the engine is accepted.
