1991 Mercedes Benz E Class engine oil in hydrolic suspension bottle

first thing i would do is go back to who ever fitted the recon engine for you as you will have warranty and have them resolve the problem because if you do anything to the engine hen you could void your warranty and have them look at why you are getting engine oil in the suspension spheres there is oilin them anyway so are you sure that its engine oil as you mentioned

I have had this problem myself where the hydraulic oil in the self levelling suspension reservior kept overfilling with engine oil. The only connection where the two systems are joined is at the self levelling hydraulic pump which is attached to the engine camshaft. I found the shaft seals of the pump worn which let engine oil into the pump and therefore the suspension system. If you go to a Mercedes dealer you can get a seal kit for the pump for around £15. Do not replace the pump itself as they are around £800.