1988 International Truck s engine timing

Is it a diesel? I will guess yes. You will have to pull the front cover off, there are timing marks you need to line up. You will also need to time the injector pump, I believe they were 19 to 21 degrees. You really need a manual, or at least a printout of the page showing you the gear arrangement. This is not hard to do, but you really need the paperwork. Good luck.
Mickey-d