I was a man who experienced frequent prepatory discharge, so the Messenger of Allah ﷺ said to me, "When you notice the prepatory fluid, wash your private part and perform ablution as you would for prayer. But when semen gushes out, then perform the full bath."
أخبرنا قتيبة بن سعيد وعلي بن حجر واللفظ لقتيبة قال حدثنا عبيدة بن حميد عن الركين بن الربيع عن حصين بن قبيصة
كنت رجلا مذاء فقال لي رسول الله ﷺ إذا رأيت المذي فاغسل ذكرك وتوضأ وضوءك للصلاة وإذا فضخت الماء فاغتسل
[Its chain of transmission is sahih] Abu Dawud narrated it in the Book of Purification, chapter on madhi, hadith no. 206, from Qutayba, with this wording. It is also found in Sunan al-Kubra, hadith no. 199, and Ibn Khuzayma and Ibn Hibban graded it sahih. Ali bin Abu Talib ordered Ammar and Miqdad to ask him (the Prophet), so they asked, then he himself asked. See Ihsan, hadith no. 1099, and elsewhere, so there is no contradiction between the hadiths.