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Oil change
During the years of maintaining cars (high amount of BMWs) it was clear that the wrong lubrication made a large impact on wear on especially single camshaft engines. Over the years different manufacturers of lubricants were selected and used. Only one fulfilled the requirements which is still used nowadays in the automobile shop. That one is Mobil 1.
With a large amount of viscosities and grades, Mobil 1 will have the right oil for your engine, gearbox or differential. If the oil is not available we will always use the highest grade selected by the manufacturer of the vehicle/engine/gearbox or differential. An example is the 6 speed automatic gearbox used in the BMW E65 7 series, E60 5 series & not mentioned models. The only appropriate oil for this ZF 6HPXX automatic gearbox is the longlife oil from Shell (type M1375.4). When we replace the oil and filter of your gearbox we will use this oil and OEM filter replacement.
Advanced maintance
Were most people avoid working on highly sophisticated systems like variable camshaft (valve train) systems, individual throttle bodies or valve tronic systems. Tom Karreman finds these systems a challenge to work on. Not all repairs in the past were successful the first time but Tom made it eventual work and gained a certain work-flow to work on future systems to avoid failures after a repair.
Below a list of executed work is presented were special tools are required for and knowledge to fix or adjust the system to factory (or your) specification.
-Valve adjustment of the following BMW ///M engines (M88, S14, S38, S50B30 & B32 Europe, S54B32). Later produced engines were fitted with hydraulic lifters.
Throttle body synchronization of the following BMW ///M engines (M88, S14, S38, S50B30 & B32 Europe). Later or not mentioned
engines were fitted with ECUs that handle automatic individual cylinder mixture adaption.
Mentioned models can be adjusted by air-by-pass screw or the injection time can be adjusted in the ECU (S50B32 with MSS50 ECU). A vacuum and or exhaust gas measurement (CO%) can be used to synchronize the throttle bodies. A basic setting of all throttle bodies will first be checked and adjusted when necessary and
possible.
-Variable Nockenwelle System, Variable Camshaft System
-Left: Valve timing graph BMW S50B32.
Right: VANOS Unit S50B30 1.High pressure pump, 2.VANOS gear, 3.Chain sprocket for inlet camshaft, 4.Connection to pressure accumulator, 5.Pressure limiting valve, 6.Filter & 7.Solenoid valve block
VANOS inspection, replacement or repair of all BMW and BMW Motorsport (///M SxxBxx) engines. VANOS faults can lead to performance decrease and noise from the engine. Karreman Engineering is able to inspect a wide range of BMW engines by diagnostic data on functionality. Besides electronic functionality checks, mechanical inspections can be performed.
Maintenance
Maintaining your car in top condition for a reasonable price? You are at the right place at Karreman Engineering. Tom Karreman who’s son of Aart J. Karreman (Jr.) started to work on early age at his father’s automobile shop which started by Aart’s grand father in 1936. Automobiles were rare in these days but grandfather (also called) Aart Johannes Karreman made a successful business in these days. His son Klaas took over the company which Aart Johannes Jr. took over in the early 90’s. Besides a dealership of BMW which ended in 1982, dealerships of Renault and Mazda were obtained over the years. Dealer requirements and the eventual high costs that the customer needed to pay in the end were one of the many reasons to stop with dealerships. Instead of that a focus on specialism was made.
The knowledge obtained during these years is forwarded to the people working in the automobile shop.
