Setting Timing

[The Dan]

The crank is lined up EXACTLY with the mark on the oil pump... i used a mirror to make sure it lined up properly.... even turned the engine a million and one times to get all three white marks on the belt to line up too!!!

I posted the pics of the balancer also.... what do u think of its condition???

That mark is not perfectly lined up.

Turn it another degree clockwise.

[Guilt-Toy]

my engine lines up to the second mark on the harmonic balancer as tdc, has been like this for years

[grigor]

If you are really worried about it why don't you use a dial indicator and check when you piston is at TDC to verify your marks etc? then you may be able to adjust your marks on your front cover to suit exactly.

No need for all that.

I PM'd Smell a while back to find TDC via a piston stopper and remove all this balancer guesswork.

Time to move on.

[Guilt-Toy]

how about posting that info here?

[grigor]

how about posting that info here?

Not really the right section but....

A piston stopper is nothing more than a means of stopping No 1 piston before TDC, usually a modified spark plug or similar.

Take the usual precautions regarding cleanlines etc.

Rotate the crank until the piston touches the stopper and mark the balancer (or your degree wheel) against a fixed point.

Rotate the crank the opposite direction until the piston touches the stopper and mark the balancer against that same fixed point.

TDC for No 1 will be halfway between those two marks.

The larger diameter of your degree wheel improves your accuracy but even the balancer's diameter is better than the tiny crank gear.

[Don Dada]

Well guys some new info on this.....

I fabricated and used the piston stop as grigor suggested and i must say it worked a treat!.... so much so that i realized that my balancer has NOT rotated and the orange 0* mark lines up at TDC mark on the backing plate when the engine is in fact at TDC.

So now if i use the orange 0* mark on the balancer to get the engine to TDC none of the marks, ie. crank neither cams line up with their respective marks on the backing plate.... they are all just a tad too much clockwise.

I don't' have pics of the crank, but the reason why i say it would be a tad too much clockwise is because when all three dots line up perfectly including the three white marks on the belt and when i slide on the bal it reads about 4-5* advance , so obviously when i now turn the bal to get it back to the 0* mark all three gears would have rotated clockwise some.

Have a look at these pics with the balancer set to 0*

Notice the mark on the backing plate is just off the tooth of the gear and not dead center

Intake

Exhaust

TDC

I even took it to a mechanic and he was puzzled as well to see when he lined up all three marks and put the bal back on it read 4-5* advance..... so i know i'm not crazy!!!

[The Dan]

Yeah and the backing plate is mounted on rubber inserts so it could be off too. And the lower timing cover could be off as well as it's in rubber washers too.

You should go and buy all new parts and fit them, that way you can find out that you are making a huge deal over nothing and none of it will matter when the engine is running.

Also, take the shot of the cam gear from front on, not at an angle. Make sure it's parallel. Taking shots from an angle distorts the ability to view it for every degree it's off. Considering you are chasing 2-3 degrees then this is very important

[Don Dada]

I am definitely not a mechanic but all rbs i've changed timing belts on before had all timing marks lined up spot on and the bal on 0* at TDC ..... i mean Nissan would not have but those marks there if they didnt intend on you to use it would they????

[grigor]

My thoughts, as sent to Smell, are that he’s now reached manufacturing tolerances and anything closer will require adjustable cam wheels.

Obvious stuff like a decked block or shaved head have been eliminated as the cams would have retarded not advanced.

A thicker than factory head gasket also seems unlikely.

Can’t recognize the marks on the cambelt but I don’t like thicker than factory aftermarket cambelts as they advance cam timing due to the extra thickness over the idler.

I dug out a few Nissan belts and the root of tooth to back of belt is constant at approx 2.3mm

However the top of tooth to back of belt varies from 5.2 to 5.6mm.

15thou mightn’t sound like much but it doesn’t take much extra at the idler to advance the cams.

Gates belts are another story.