R16 noise, help me out

[cbez]

@JT Yes, it seemed fine.

@DAC21 it was rebuilt 10+ years ago (the pic I was given was a developed film photo, if that gives you any idea...), then sat in storage, not run until this year. It was given to me running fine and idling quietly and developed these issues in the first 100 miles. Yes, it was done by a fairly well known person in the Datsun community (actually, the engine builder he uses). Even if he were to say 'bring it back I'll get everything fixed up for free', which there is no guarantee of, I am not really inclined to hand it over for the months that would take (I already waited almost a year to get the car), when they built it this way in the first place. I am not really a drama/call people out kind of person, rather just dig into it and get my engine running right.

12117-P5112 should be right for the rod bearings, if I can't find NDC? Seems like it replaced 12117-P5100?

[JT68]

JT I’m surprised to learn that the oil flow is so different. Good to learn new things from the knowledgeable members we have here. As I said, I have little knowledge of the R16, nonetheless with all the trash he has found and the lack of flow to the valve train I wouldn’t feel comfortable until the engine was thoroughly cleaned.

Yes, that is why the big difference in the two pumps (~+25% for the 2L). 2 tensioners, the 2L cam probably throws 3-4x the volume of the 1600 rocker asm and the extra crank feeds-yep, that is why most 2L's show minimal pressure at idle.

And I agree, at this point I would probably tear it all down too, clean everything and find the root cause of the flow problem.

I would definitely find the NDCs or mic the crank and measure the bearings diameters to verify clearance.

[cbez]

I could do plastigauge on some .25s? Not seeing any NDCs.

Right now I am inclined to do new rod bearings, put the pan back on and just test flow step by step with the starter. I know the head passage is wide open. I know the rocker is flowing now as I was getting fluid out of it with just a WD40 can. If I have flow issues in the block it should be immediately obvious.

[Gregs672000]

I have a U20 pump in my stroker and the gauge reads the same for the most part. Frankly I'm not that trusting about accuracy of the stock electric gauge. I've thought about hooking up a mechanical just to compare. As I noted before there is no lack of oil when I take the valve cover off or anything else. Have to keep a roll of paper towels handy.

I've done that (hooked up a mechanical) and confirmed the stock electrical gauge is wildly inaccurate. I had good pressure all the time per the mechanical.

[Gregs672000]

Have you checked your valves for scoring or bends Yet? Curious.

[Curtis]

There are repco 10 under rod bearings on ebay now and Carl Jaeger in Canada has them for $59. JT should have them and some of the other vendors. JT will no doubt give the help you need more than anyone else.

[cbez]

No scoring I could find. They all seat nice and straight and the tops are smooth where the rocker rides. Pulled a couple that looked normal and got sick of messing with the tool lol.

[unklpat]

Okay, there is noticable wear on the outside edges of the rod bearings, not something I would want to see, or have ever seen. Also, no source of metal bits in oil pan. Do you really want to just replace bearings, without finding out what happened? Metal just doesn't appear without a source. Why would a cam bearing fail, and break apart, and is that being looked at? Pat

[cbez]

I appreciate the careful approach but I'm also trying to be pragmatic and take the shortest and most affordable step to 'go'.

If it was metal from not cleaning the pan during a lazy rebuild, or machining leftovers during a lazy rebuild, I would never find the source even if I tore it all the way down. I don't know, or have any hint that any of the cam bearings have issues and the rotating assembly spins over smooth as can be. I couldn't find a speck of metal around the cam, in the pump, or below the timing components. It was pulling happily at 6000rpm before I pulled it apart. All I ever found was what was in the pan and some crud in the rocker shaft.

My next big step is just putting the pan on and seeing how the block oil passages are working.

If I put it together after that, and see how it sounds without the exhaust leak and with confirmed oil to the top end, I can run it another x miles and check for metal again knowing I started with a clean pan.

May very well turn out to be a big dose of wishful thinking but I might also avoid a big, expensive rabbit hole I didn't need to go down.

[C.Costine]

I can't really see any damage to the lobe that the bad rod bearing rides on, but I am clear over on the East coast Are you really going to put it back together without at least a polish job? Or do you have a means of closely examining those lobes with the crank in place? In addition to the gouged bearing, two others have minor but over-all scratching on them which looks like someone did a clean-up of the surfaces with steel wool or another fine abrasive. This begs the question why? and what else is hiding in the bearings that are still on?

[unklpat]

If the chain tensioner failed, that could the noise also, from the chain slapping against it? Is it possible that the tensioner feed hole is blocked? Might be worth a check. Have the pushrods been checked? Assuming metal is random, I'd check every possible source of noise in the moving parts. Pat

[JT68]

I think most of us a kinda saying the same thing in different ways:

1. I don't see anything on the crank that needs machine work-at least in the photos. yes polishing the crank would be good form. All the bearing observations are minor, the worst being the garbage that ran through it.
2.sitting for 10 years is never a good plan for any engine, rebuilt or not. too bad on that. Some lubricants turn to chalk after a few years. Rust and corrosion forms where it should not be.
3. you still have not found the root cause of the oil starvation unless it was a clogged rocker shaft. Sounds like that is still the plan.
4. If you address#3, clean it up and reassemble it properly, it should chug along for years.
5. I'd still have a shop check out the head since some valves seemed to be sticking.

Your strategy is sound, too bad it all went this way.

Suggest you find the actual NDC-.25's, that way the clearances will very likely be correct. Other brands will vary slightly and you probably don't want anything tighter on the journals. I'll check, it's possible we have some, other vendors may as well.

To answer Pat's question, unless it was a bad rear journal on the cam, simply too tight when assembled, dry install or startup, or more destruction from trash/sitting, the only thing that would kill that rear bearing is an install with the oil holes out of position, Most machine shops are careful enough to get this right, so it's not super likely. I'm crossing my fingers for you and betting the rockers are/were dorked up and that was the cause all along.

That rear oil galley on the block is a straight shot down to the cam bearing, so you can insert a 3/16 or 1/4" rod/brush/dowel etc down it to make sure its open and then blow some oil back out before putting on the HG. The rod should go down 4 7/8" inches and then it will hit the cam bearing. If it does, that rear passage isn't blocked unless the bearing was installed wrong. You can clean it with brake cleaner and chase that with wd40

I guess cleanliness that is another advantage of the big aluminum sump, since the baffle is removeable, its easy to clean really well. Not so with the stock steel pan. NO matter how much you clean, it is impossible to know if there is trash hiding under the baffle.

Anyway, as long as that rear cam bearing flows oil, you can put the lower end back together with whatever level of retentiveness and precision is appropriate for the job. Best of luck with it!

[Curtis]

This reminds me of when I asked the machinist about assembling the short block and letting it sit for a while. He immediately replied engines don't like to sit. So that put my plans on hold. Just as well since I changed my mind about what I was going to build. But I was thinking but what about if it is completely lubed and protected. Our local guru likes to use Clevite assembly lube. I had always used half Power Punch and oil.

[Gregs672000]

I appreciate the analysis, discussion and decision-making process here... I can relate it to many car decisions made over the years, some good, some bad. I also appreciate the steadiness of cbez as he digs into it. I'm sure there's a level of frustration there, but as you know getting overly upset does nothing for you and wastes your energy... you just have to set your jaw and do it. Apparently this car is carrying some abandonment issues and testing your level of affection and commitment. You two will become even more intimately connected through this process (or am I just weird? Oh wait, that's a given...).

[Datrock]

Not sure if you have the timing cover off or not, if not, to help track the noise and metal in the pan issue it might be worth checking out under the timing cover to see if things are correctly installed. Over the years I have seen anything from oil slingers behind the crank sprocket and cam sprockets not fully in place, so I'm just sharing what I have seen. I know of times where the woodruff key gets pushed out of the slot while installing the sprocket and chain and the engine builder doesn't notice it. A couple people on here even had the front of the cam break off after a very short time. I have also removed the cam and found it rubbing against the plug in the back of the block due to the two sprockets trying the align and the cam floats so it was moving toward the back of the engine. Also have found where the cam sprocket was so far offset with the crank sprocket that metal was getting torn away on the back of the cam sprocket and along with allot of unusual tooth wear. Plus as to oil flow getting into the head, what I have noticed is a 1600 cam has a slot that allows oil to get into the head only one rotation at a time, it is not like the jack shaft of the U20 that has a wide open slot so oil flow is not as restricted. A recent discovery was a 3 main that I once put together it was missing a blind plug in the bottom of the block and I missed that, the engine ran grat for over a decade relying on oil flow but always had low oil pressure and an idle noise similar to a U20 death rattle, by just plugging the oil galley hole fixed both issues that the engine had. Just a few thoughts to try and help....Bill