Datsun Roadster Forum-311s.org

The service manual for the R16 doesn't mention pre-lubricating the oil pump after removal and cleaning. It just says to make sure it's clean when you reassemble.
If it was me though, I'd feel better if I had something between the end plates and the gears at start-up. If only to help it prime.

my understanding about priming the oil pump is to place a long screwdriver in the distributor shaft and manually turn the pump about 20-30 times to prime all the galleys and make sure everything is flowing.

thanks for all the input, I am reworking my engine rebuild and will be back on track shortly.

Thanks,

Cris

Turning it by hand with a screwdriver will not be enough to prime the engine. You will need to make an adapter to drive the pump with a speeder bar (looks like a breaker bar with a "U" in the middle) or prefferably an electric drill. Be sure to let us know what you found upon disassembly that was causing the issue.

Mark

Been a while since I checked, but doesn't it need to turn counterclockwise?

After priming up the oil pump by tuning it with a drill. Will the oil be visable on the cam and other parts to know it is primed.When I rebuilt my 510/L18 I cranked it over with the plugs out untill the oil preasure light went out.But the plugs in and it fired right up.It is a must on the L engine to fill the pump.
Arnold

Back on topic - from what I've read it sounds like the piston installation is where the excess "drag" started. CHECK the ring end gap! They aren't gapped right out of the box.

Two things about priming pumps. Sometimes a pump just doesn't want to prime. I have luck in those cases with filling the oil gallery / oil pump using a pump oil can to pump oil into the oil pressure hole. It usually takes a less than a quart. LOL

After a few times of having to prime the oil gallery I Now always coat the inside of the pump and gears with a LIGHT coat of grease. The idea is for the pump to produce just enough vacuum to pull the oil into the pump.

I just got back my stroker from the engine builder a while back. I CAN NOT turn the crank by hand either. I would think this is normal. A loose rotating assembly is probably not a good thing. On the other hand...I would not attempt to assemble a new engine my self. If i were just replacing bearings or reringing maybe, but once the crank is out and the mains have been removed or retorqued, I would get someone experienced involved.

It will make the difference between your engine lasting 5,000 miles or 100,000 miles.

Good luck.

eastmedia wrote:. On the other hand...I would not attempt to assemble a new engine my self. If i were just replacing bearings or reringing maybe, but once the crank is out and the mains have been removed or retorqued, I would get someone experienced involved.

It will make the difference between your engine lasting 5,000 miles or 100,000 miles.

Good luck.

Well now you have me worried By bearings, I guess you mean rod bearings in this case. What, exactly would be the critical aspect of the crank coming out and going back in then? We have the plasti gauge info posted above. Not mentioned was keeping main caps going back into the proper spot (number them if not stamped). Cam bearings certainly should be done the machine shop, but what am I missing with the crank?

MTyler wrote:Well now you have me worried By bearings, I guess you mean rod bearings in this case. What, exactly would be the critical aspect of the crank coming out and going back in then? We have the plasti gauge info posted above. Not mentioned was keeping main caps going back into the proper spot (number them if not stamped). Cam bearings certainly should be done the machine shop, but what am I missing with the crank?

The only thing I have not seen posted is setting the thrust. If the crank and/or block are not warn, then there is nothing to it......it should be checked.....
shade tree method LOL
Try to move the crank front to back.
If you can feel it but not see or hear the movement, then its about 3-4 thousandths OK
If you can just see it...6-7 thousandths (need to check with a gauge and decide...)
If you can hear it...Need to fix.

Ring end gap? What is that? I will Google it, but if someone wants to post the answer...

Thrust is good. I had everything machined. why I didn't have them do the build, I don't know. Probably the same reason I have never finished my time machine either.

I really am starting to wonder if it is just piston drag and I should just move on.

What should be the next step? installing chains and head or oil pump and pan?

I am currently recruiting locals who have experience.

Thanks,

cris

It's the gap the rings should have when placed in the bore. To check, place piston ring in the bore and push it down square with a piston (no rings on it) and measure the gap with a feeler gauge and compare with the spec. Not enough gap = rings seizing and taking the piston/bore along with it, too much = compression loss and oil burning. The gap is there to account for expansion as the engine warms up.

Mark

You may want to touch on the stagger of the end gaps too...

spl310 wrote:You may want to touch on the stagger of the end gaps too...

Good point Sid. I think most manuals state to set the gaps 120 degres apart. I usually just set them so no gaps line up and don't set them on the thrust side (where the pins are) I have built mulitple engines like this and have had no issues. This would have no effect on the diffuculties your having.

Mark

Good news! I did something right...I staggered the ring gaps.

I did not check the ring end gap. Do I really have to take it apart a 2nd time? I mean they are new pistons, new rings and perfectly bored and honed cylinder walls.

Don't answer that...I don't want to know.

*SIGH*

I will let you know.

Thanks again (seriously)

Cris