If the timing belt snapped ( :mad: ) what needs adjusting before the new belt comes on? My mechanic said he may need some adjusment info or such before fitting the timing belt to adjust the pulleys maybe? IDK, any info welcomed.

If you look for the on-line manual, there is a section on the timing belt set up showing all the markings on the pulleys, auto-tentioner and the adjustments, positions and clearences needed prior to instalation, also on the 300zx.org web site there are some handy tips on replacing your belt and the set up required, this will be very handy for your mechanic as there can be slight variations and tolerences allowed on the pulleys. If the belt has broke under load then your mechanic will have to carry out a thorough inspection. Hope this helps mate. :cool:

If the timing belt snapped ( :mad: ) what needs adjusting before the new belt comes on? My mechanic said he may need some adjusment info or such before fitting the timing belt to adjust the pulleys maybe? IDK, any info welcomed.

 

 

read my pm

Chances are if the belt snapped at speed you more than likely damaged and bent some valves, i hope this isnt the case though.

Chances are if the belt snapped at speed you more than likely damaged and bent some valves, i hope this isnt the case though.

Yeah thought the same but she cut out just as I stopped, tried starting her again and no knocks or anything just high note starter motor if you know what I mean so fingers crossed.

this happened to me in an escort RSturbo I had, had just been kicking its head in then pulled off a round-a-bout gently and it cut out, cranked over really quickly so I just got it recovered to work, took the head off the next day and I had bent 6 out of 8 valves, was gutted because I had already bought a timing belt as I had only had the car 3 days and was going to change it after work but being young and stupid I just took a quick peek under the cover and thought ah it'll be fine till the weekend! doh!

Usually get away with it on a Z. I won't go into the reasons why but I'll keep my fingers crossed for you

As a V6 is two three cylinder engines in effect the camshafts can settle off lobe quite easily avoiding any valve damage.So its worth trying a new cambelt on the engine as you may have got lucky :) .

There are two distinct failures of cambelts, the first been due to age / wear which will be clear to see from the belts appearance of cracks/ splits, random loose or missing teeth, and as other learned replies above mention in all probability when a belt fails in this way then your 99.9% in the clear due to the cam lobes settling with the valves closed.

 

Retiming the cams, the crank and resetting the adjuster before trying another test belt on is a simple job that any mechanic should be able to handle.

 

However the belt failure may also have been caused by a seized or semi seized camshaft usually on the right hand bank in most cases ( so I am told ) the belt damage will look very different, often the belt is still intact and tentioned but a small section of teeth will have been pulled off in the lower crank pulley area this is obviously much more serious, this is where inspection of the belt and cam pulleys is essential.

 

Any seized cam will stop the belt and as the crank continues rotating it rips off the teeth it is contact with, as an upshot of this it is more likely the cam lobs will not settle with the valves closed so valve/ piston damage is more likely.

 

Inspection will very quickly reveal the failure cause and hopefully it was just an old belt that should have been changed earlier, good luck

 

 

Daveman

Quick update: Things just didn't go tp plan today, spent 12 hours changing the cambelt :rolleyes:

the teeth on the old belt simply ripped off near the crank shaft and other few places as well but not as bad.

Thankfully she started without problems and ran sexy smooth, I'm over the moon.

 

Cheers :duffer: .

Quick update: Things just didn't go tp plan today, spent 12 hours changing the cambelt :rolleyes:

the teeth on the old belt simply ripped off near the crank shaft and other few places as well but not as bad.

Thankfully she started without problems and ran sexy smooth, I'm over the moon.

 

Cheers :duffer: .

Lucky....

Quick update: Things just didn't go tp plan today, spent 12 hours changing the cambelt :rolleyes:

the teeth on the old belt simply ripped off near the crank shaft and other few places as well but not as bad.

Thankfully she started without problems and ran sexy smooth, I'm over the moon.

 

Cheers :duffer: .

 

 

great news bud, looks like you got off easy this time :)

Really happy for you mate. :)

Real lucky.

 

Glad it's sorted and not too bad.

 

BTW, 12 hours to change a cam belt is fair on average on a 32. :)