im working on my first 71 240 z project car and i cant locate the timing marker(plate) that corresponds with the crank to set timing. one of the front cover bolts is missing, and it looks like this is where it would go-----if there is one on this car--------i imagine there would be. front to rear its on the left side. if there is does anyone know where i could buy one. please help. thank you . steve

I don't know that I can give you a definitive answer, but here is some info that might help.

According to the 3 L24 engines I have (71,72,73), the timing marker plate must have been changed btwn 72 & 73. Both the 71 and 72 timing chain covers have a marker plate (1/2" wide, single point) mounted just above the oil pump. The 73 timing chain cover has a marker plate (2" wide, multiple degree points) mounted below the distributor.

Since you have a '71 car (and I assume the engine is of the same vintage) I believe you should be looking for the single point type plate, which will bolt onto the cover just above the oil pump.

I don't know why this is the case, but this is what I have determined from viewing the 3 engine I currently have. Good luck on this and if anybody has a reason as to why Nissan did this, please share it with us.

I've attached a picture of the timing mark pointer on my L24. 11/69 production and it is the original engine.

Hope this helps.

Originally posted by kmack

According to the 3 L24 engines I have (71,72,73), the timing marker plate must have been changed btwn 72 & 73. Both the 71 and 72 timing chain covers have a marker plate (1/2" wide, single point) mounted just above the oil pump. The 73 timing chain cover has a marker plate (2" wide, multiple degree points) mounted below the distributor.

The 73 240Z that I owned had the timing scale that kmack describes for a 73, but it was mounted on the passenger side of the car timing cover. "Zero" was in the exact same location as it would be on a 70, 71, or 72 240Z with the little arrow type pointer shown in the attachment on the post above this post.

I just bought one of these scales to incorporate in the 72 L24 that I had rebuilt for Bambikiller.

***EDIT: I think that the one described by kmack may have been for cars equiped with AC or Auto Trans 240Z's

thanks guys for all the advice---i went to my local nissan dealer ( garden grove, ca ) and they had the marker plate for 2 bucks.. good deal------steve

Originally posted by sawilliams

thanks guys for all the advice---i went to my local nissan dealer ( garden grove, ca ) and they had the marker plate for 2 bucks.. good deal------steve

Steve: Which one did you get from Nissan for two bucks? The little arrow, or the one with the number scale? Just curious.

Carl

i got the arrow one because that was the only one listed for 70-73 240's----------- sept of 73 the plate changed. but he didnt have a pict of it. the guy said the 260s and 280s of those early years are where ,if i want, i can get the plate with multiple degree measurements. just for now i got the sigle point marker------cause i had to order it----plus i havent even looked up where to set the timing -----and the details of switching them can wait just a little. it was actually 1.12 and they have the one with the degrees on it for 2.50----ill just take one step at a time for now so i can move on to something else and get her runnin asap . ive got an e31 head -----there the high compression ones arent they. ive heard theyre good. thanks again for your help. steve

Originally posted by sawilliams

i got the arrow one because that was the only one listed for 70-73 240's----------- sept of 73 the plate changed. but he didnt have a pict of it. the guy said the 260s and 280s of those early years are where ,if i want, i can get the plate with multiple degree measurements. just for now i got the sigle point marker------cause i had to order it----plus i havent even looked up where to set the timing -----and the details of switching them can wait just a little. it was actually 1.12 and they have the one with the degrees on it for 2.50----ill just take one step at a time for now so i can move on to something else and get her runnin asap . ive got an e31 head -----there the high compression ones arent they. ive heard theyre good. thanks again for your help. steve

The ones with degrees were avail on at least some 73 Z's, I've forgotten what mfg date (I looked it up in the Parts CD) and it was listed for Manual Trans cars. Either one will work for you. i just like the look of the "scale" and I got one from a Z boneyard in Oregon.

The E31 heads are indeed high compression heads, they also have smaller valves than some of the later heads.

i like the look of the scale ones too and will get on----the marker is just a quick fix now so i can set the timing to get her runnin. im really not that familiar with the advantage/disadvantage of smaller vavles. can you give me the scoop. thanks. steve.

Originally posted by sawilliams

i like the look of the scale ones too and will get on----the marker is just a quick fix now so i can set the timing to get her runnin. im really not that familiar with the advantage/disadvantage of smaller vavles. can you give me the scoop. thanks. steve.

Larger valves, when installed in the E31 heads will allow the head to breathe better. Not that they aren't OK as they came from the factory, it's just that they can be made even better by spending money on having a machine shop (that knows what they are doing) install bigger valves (I think they use 280Z valves). Also the E31 heads came with soft valve seats that should be replaced with hardened ones when (if) you have a valve job done to the head. Any competent "Datsun/Nissan experienced shop" will know about all this more than I do.

Looking at the timing marks on the flyweel pully is the first one 0 degrees? then does it go in 5 degree increments? accrding to my book it does but mine is way off, BUT I just bought my 72 and it runs really bad.

according to my FSM and my experience, the first mark is 5 degrees AFTER Top-Dead Center.

Should be 5ATCC - 0 - 5BTDC - 10BTDC - 15BTDC - 20 BTDC