Valve damage

STUARTC

MEMBER
2006 RENAULT SCENIC
2.0L
4 CYL
2WD
MANUAL
65,000 MILES

Hi, I'm assessing the vehicle listed above with a 2.0 16v F4R engine for valve damage following a timing belt break (caused by an aux belt fail - gah!). So far I have established that the engine turns freely and also both camshafts spring around fully unhindered. This appears to be a good sign and is why I'm trying to avoid taking off the head if it may not be necessary! However, using an endoscope through the spark plug hole while turning the camshafts by hand - to try to get a better view of the condition of the valves - the valves don't appear to be moving. My question is whether this is likely to be a sign of damage (even though the cams seem to be moving normally), or could simply be lack of pressure in hydraulic lifters meaning the camshaft isn't actuating the valves. Of course, I realize that there being no valve damage in these circumstances is a pretty long shot, but other signs are good so I'm taking baby steps! Any advice you can offer would be very gratefully received.
Many thanks, -Stuart-

1 Reply

4DRTOM

MECHANIC
467 POSTS

Hello,

I have found that you get lucky if the cams do move freely the valves didn't get bent and you are probably good. The only way to know is to take them off or put the new belt on and give it a try. If when the new belt is on and you have rotated the crank a few complete turns by hand and nothing is binding and you feel compression building in the cylinders this would be a good sign.
Tom