QuestionQUESTION: I have a renault master van and I need to change one of the pistons. How hard is this to do ? and do u have any advise or tips ? Thanks
ANSWER: It is a lot of work, Why do you have to replace a piston? The procedure entails removing the cyl head and the sump in order to get to the connecting rod big end. You will need a ring clamp to fit the piston into the bore, you may be opening a "can of worms" and it may prove sensible to do other things while you have it stripped down. Such as a valve re-seating, cyl head rebuild, new main bearings, radiator service, belts & hoses and the thermostat checked.
---------- FOLLOW-UP ----------
QUESTION: Basically whats happened is someone put petrol in it instead of diesel I took the head off and found a hole in one of the exhaust valves and a chip in one of the pistons. I've had the valve replaced and reseated and the head skimmed. I now have the sump off and will try and get the piston out tomorrow. Getting parts seem to be a nightmare the piston is £175 so cant afford to replace to many things. If you know anywhere I could get cheap parts for renaults I'd appreciate it. Thanks
AnswerWell, it sounds like you are dealing with it very well, there are few "cheap" sources, check out the web and scrap yards. It sounds like you know what you are doing, turn the crank to bottom the piston, now you can undo the nuts. Remove the lower bearing cap then fit a piece of rubber tube (hose) over the protruding bolts, move the piston back up, then with a piece of wood tap the connecting rod out. You will need a ring compressor to re-install. With the bolts still covered, lubricate the bearings and install the piston, now tap it down gently with a wooden pole (hammer shaft) until it seats snugly, refit and torque the nuts. Good Luck
