hifi engine


I have just got hold of the above cassette deck.All is well,great sound quality on playback,nice tidy machine.The only problem is it will only record when the record level is pushed all the way to the limit and when it does record it does it badly,with any underlying recordings showing through.I do not have a manual but I don't think I am missing anything,recording is a simple matter.
If anyone may have any ideas as to what may be wrong I would like to hear any comments.
Many thanks.