Datsun Roadster Forum-311s.org

What is the proper Torque for the two nuts on the Aluminum valve cover for a 1969 2 liter? I'm always Leary to over tighten and crack aluminum cover !
THANKS,
Bob

"Barely more than finger tight," as Dann Bramhall (Rallye Roadster) once wrote. You are wise to be cautious! If it leaks, a new gasket may be in order, as they do lose elasticity over time and numerous heat cycles.

bobs19692L wrote: Sat Feb 12, 2022 2:52 pm What is the proper Torque for the two nuts on the Aluminum valve cover for a 1969 2 liter? I'm always Leary to over tighten and crack aluminum cover !
THANKS,
Bob

Seems I read 4 pounds, I'm probably wrong and anyway do any torque wrenches even go that low? So yeah hand tight seems right.

Thanks for the information, most likely the torque is in inch pounds. I've been a little more aggressive in the past! I'll be a lot more cautious in the future! Thanks for the quick response.
Bob

bobs19692L wrote: Sat Feb 12, 2022 4:51 pm I've been a little more aggressive in the past!

You are not alone, Bob: Why Nissan would use those honking great 22--24 mm (they did vary by at least that much during production) hex head nuts which would seem to require a 12" Crescent to tighten is a mystery.

Many vc perimeter style bolts are 9-16 inch lbs
I'd say lite wrist tight with a rachet
New cars with the same middle VC tightening position have a stop to the stud so as to prevent bending the VC

It's like the no 2 ( low setting ) on your air ratchet

Take the nut to contact with the valve cover and 1/16 to 1/8 turn more. Less is better, if the valve cover leaks then take the gasket off set and set it on the head without the gasket. One of two things and occasionally both. One the head has been apart and the studs that hold the cam towers on were put back upside down, there are more threads one the end that goes into the head and the valve cover high centers on one or more. Easy fix put a plastic bag or sheet of plastic over the stud, poke the long ones through and grind them until the valve cover doesn’t high center on them. Item number 2 the head has been surfaced and per many people just to the ends of the cam towers and there is gaps at each end. For this I use heavy nylon string in the gasket grove at each end to force the gasket closer to the the head making a better seal. Dave

The Datsun Roadster book shows 5 foot pounds for the R16 and no listing for the 1500 or U20. I would think that figure might be applicable to all three. I use an inch pound torque wrench for anything under 20 ft. Lbs. Torque wrenches are most accurate in their middle range.

‘Tom’s Tech Tips’ on Datsun.org indicate 10 ft-lb for the R16 and 5 ft-lb for the U20 … Not sure why they would be that different?

http://www.datsun.org/roadster/resources/tuneup.html

I like the nylon rope trick!

spl310 wrote: Sun Feb 13, 2022 6:49 pm I like the nylon rope trick!

???

I saw Dave’s post but I don’t get it

I'm trying the silicone gasket out. Seems nice so far.

Not sure the ft lbs is a bit deal...it's not like it's under pressure with that huge breather. If you have two flat surfaces and the gasket is still soft it should be fine...

So if the U-20 head overheats and warps, the preferred method to repair it would be to heat the head and press it back to flat. Aluminum heads grow greater than the block they sit on if the block is iron based. The more common method of repair is to pull off the cam towers and machine the top and bottom of the head. If the head is cut quite a bit it creates cam chain issues and a few other problems. I have found a number of heads cut as recommended by Rallye where you only cut to the end’s of the towers, one and five. So what happens is the head drops away on the ends from the valve cover. So if you set your valve cover on the head without the gasket you can see where the gaps are. Then you can put heavy nylon string in the gasket grove to help push the gasket into better contact with the head giving you a better seal. Dave

david premo wrote: Sun Feb 13, 2022 8:53 pm … So if you set your valve cover on the head without the gasket you can see where the gaps are. Then you can put heavy nylon string in the gasket grove to help push the gasket into better contact with the head giving you a better seal. Dave

Ingenious! Thanks.

Thank you all for all the information. I've owned my 69 Roadster since 1971 and removed the valve cover numerous times, and I have been over tightening to much. I will feel more comfortable when tightening next time! Thanks again! Bob