Nissan Repair: nissan serena cd20 diesel it wont start, competent mechanic, compression stroke

Question
hi sir my nissan serena broke its timing belt few days ago i had it check with the mechanic and replace the parts in the cylinder head valves,tappets. when the mechanic returned all the parts make the necessary timing. the car don't start it just produces smoke and by the way sir it is an automatic transmission. what seems to be the problem? before the belt was broken i can easily start the engine. sir hope you could share a light to my problem thanks.

Answer
Hi Jefferson -

The timing marks relative to the belt needs to be checked again. Ask the mechanic to check that. Place the bottom pulley at top dead center, with #1 cylinder coming up on the compression stroke. Then there are a couple places that need to be aligned on the camshaft sprocket the bottom damper, and the cylinder head. Your mechanic should know where these all are.

Also, if the timing belt just broke while driving, there is a chance that the valves are damaged, and the car will not start. To check this, take a compression test. If there is little to no compression in one or more cylinders, the vehicle will also need a valve job.

Hopefully ypou have a trained and competent mechanic, as this is a big job that takes precision

Hope this helps -
Aloha
Calvin