Datsun Roadster Forum-311s.org

Attention all G-15, R-16 and H-20 engine owners JT68 has provided an article to the tech wiki regarding problems with timing components used in the G-15, R-16 and H-20 rebuilds. This incredibly important information to be sure your engine run right. I recommend all owners of these engine read this tech wiki bulletin.

G-15R-16-H-20 Engine Owners

Dave

Excellent research & write-up guys! Clear and to the point. This will save enthusiasts a lot of growing pains (and $$$) going forward.

Agreed, excellent work and long needed. Well done by the 311 family!

How many of the gears are NLA?

All those part numbers on the wiki are NLA from Nissan, however we do have some of all types on hand and can make additionals if we run out.

The numbers are provided as a reference for anyone who might find an NOS sprocket in the box. The photos can also be used to
positively ID sprockets.

The SAE sprockets we have are correct SAE sprockets and do not use an offset key.

A problem with offset keys is they can very easily be installed backwards, making the timing error even worse. As explained in the Wiki, offset keys are not needed with correct sprockets. Since cam timing is a royal pain to change in the pushrod motor, (drop the pan, remove the radiator, all the accessories and front cover, etc.) You really want to get it correct the first time.

Well here is a thought, it's making reproduction gears why not make one that will work for either metric or standard? All it would take is two keyways and two timing marks.

Yes, we already did that. If you have a metric crank sprocket use the metric position and mark, If you have an SAE crank sprocket, use the SAE position and timing mark. It will fit either cam.

Paul Wells has a few on hand too.

We might make a SAE crank sprocket if needed, but it probably isn't except maybe for race engines and there are not many of those around.

Next question. The 1600 and 1500 SAE cams will interchange as far as I know. They have slightly different part numbers but have the same cam gear number.

I'm wondering if it was just a change for the two engines or the grind was slightly different since stroke and bore are different.

From my research, the G15/R16 cams use the same grind. Pat

Great info! Thanks for putting this together.

spl310 wrote: ↑Thu May 26, 2022 9:39 am Well here is a thought, it's making reproduction gears why not make one that will work for either metric or standard? All it would take is two keyways and two timing marks.

Looks like they are already made and ready to go

https://datsunparts.com/collections/eng ... ponent-set

Yes, we already built them because folks were having such problems!

If you have a metric crank sprocket use the metric position and mark, If you have an SAE crank sprocket, use the SAE position and timing mark. It will fit either cam.

Paul Wells has a few on hand too.

We might make a SAE crank sprocket if needed, but it probably isn't except maybe for race engines and there are not many of those around.

All the timing parts are in stock.

LT/JT
Datsunrestorationproducts.com
Only the very BEST parts for your Datsun- 10000's of items in stock

datsun1500 wrote: ↑Thu Jun 09, 2022 3:21 pm

spl310 wrote: ↑Thu May 26, 2022 9:39 am Well here is a thought, it's making reproduction gears why not make one that will work for either metric or standard? All it would take is two keyways and two timing marks.

Looks like they are already made and ready to go

https://datsunparts.com/collections/eng ... ponent-set

This will allow me to put an SAE set on a SAE cam in a SAE engine. Then I'm done with it.

Curtis wrote: ↑Thu Jun 09, 2022 5:54 pm

datsun1500 wrote: ↑Thu Jun 09, 2022 3:21 pm

spl310 wrote: ↑Thu May 26, 2022 9:39 am Well here is a thought, it's making reproduction gears why not make one that will work for either metric or standard? All it would take is two keyways and two timing marks.

Looks like they are already made and ready to go

https://datsunparts.com/collections/eng ... ponent-set

This will allow me to put an SAE set on a SAE cam in a SAE engine. Then I'm done with it.

Yes Curtis, Both crank and cam sprockets with dual slots were made to follow the Nissan original parts as offered leaving out no variables. Approved for production by Gerhardt Gear May 8th 2022 they are in production now. We had 2 engineers at the US manufacturing plant and 2 at Gerhardt Gear inspect a variety of original new and used sprockets lent to us from 311 participants. Inspection reports were done with all of them and the new production parts. They do this work all the time and there is no guess work or crude measuring performed.
One advantage of purchasing our (set of 2) and my understanding is that our price is very affordable, is that if a customer has a 3 main early SAE engine, he does not have to reuse his old worn crank sprocket and since this sprocket turns at crank speed and had less tooth engagement with the chain, they are usually in need of replacement. New SAE crankshaft sprockets are scarce as hens teeth being discontinued years ago. Why dig through the bucket for a used part or go on the hunt for the rare item unobtainable at a high price on Ebay
We will eventually be offering the crank and cam sprockets separately, but not at the cool deal here.

Enjoy the parts!

Dean

Hi Curtis, thanks to the wiki, there is no guesswork involved anymore. It made it clear that either timing set will work with the sae cam, It just depends on what crank sprocket you choose to run. If you choose a metric crank sprocket, run a metric cam sprocket. If you have a good or new SAE crank sprocket, use an SAE cam sprocket.(or the dual fit sprocket). The SAE cam will not know the difference.

You can always give me a call if you’d like to discuss. J