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Water in sump

3K views 38 replies 7 participants last post by  Robert Bosch 
#1 ·
While re-animating my '77 280Z (200K mi.) after several years of storage, I found a quart or so of radiator water, un-mixed and with no foam, in the sump.

Inspection after removing the valve cover and plugs revealed no signs of water circulating with the oil, confirming I think, the lack of any head gasket issue that I recalled when it was parked. The engine was running fine, with no steam in the exhaust.

Thus, my current theory is that some gasket/seal around the water pump has perished from disuse, but I cannot find sufficient detail in the shop manual of this junction area of oil and water circulation to confirm.

At this point, I am resolved to replace the water pump and gaskets and hope for the best.

Any similar experiences/educated guesses/general comments?

Thanks.
 
#2 ·
The only place I know of in just about any engine that water and oil can mix is through a leaky head gasket or a crack in the head, block or some other component. Was this car left outside with the hood off (possible rain or sprinkler water)?
Also, I'm not sure what evidence you thought you could see with the valve cover off. If the motor were seeping water (thru head gasket) into the oil slowly, you might not see evidence for awhile. And then your main evidence would be foamy oil that looked like a chocolate milkshake. You would certainly have noticed that when the car was last running.
I think your planned course of action is a good one - remember to cross your fingers when you hit the starter! LOL
Be sure at some point to also check/drain the radiator to see if there's any oil in there.
 
#3 ·
Mr.6Shutr:

Thanks for taking the time to address my issue.

First off, the car was stored closed up and under cover, so it's safe to assume the source was not external.

Of course, what I was looking for under the valve cover was evidence of circulation of water/oil mix (brown gelatinous residue, tinges of rust, etc.). There was none; everything is shiny, bright, and clean, right down to the chain's crank gear. Likewise, the piston tops show none of the characteristic deposits.

This evidence pretty much rules out head/gasket issues prior to parking it. Add to this that the sump contents showed no mixing, and the radiator water is free of oil or mix residue.

It seems clear to me that the water in the sump dribbled in during storage. Since the head is higher than the radiator top tank, I don't believe it is the likely source. And perhaps coincidentally, I estimate the level in the radiator was about (just above) that of the water pump.

This lead me to check the manual. It intimated (but not clearly showed) that the oil's vertical circulation to the head happens at the front of the engine, as does the water circulation, without clear indication of proximities.

Fact addendum: my records show that I changed the water pump shortly before parking it. This makes the chief suspect in this theorem, my gasket-sealing job... if there is some cross-over potential at the water pump.

Of course, I'm just guessing here; that's why I've brought this before this knowledgeable forum in the hope of some enlightenment.
 
#5 ·
Mr.Man:

An interesting thought. 7-8 yrs., cold winters (covered but not warmed)....

There is the low water in the radiator tho.

Now, something of a retraction (meaning, I bollixed my own notes):

Clearly, the oil riser is at the side of the block; it's the oil pump/passages close to the water passages that makes a tempting culprit of unintended co-mingling.

I reckon a good foto of the front of the block/head w/o the front cover would be helpful about now.
 
#6 ·
I seem to recall that occasionally the water passage around the water pump impeller will erode through to the timing chain cavity. Removing the water pump and examining might offer a clue.

The oil pump is also in that area. Cracked timing cover maybe?

Just re-read your post on the water pump replacement. Maybe you did make a mistake there. Best place to start.
 
#7 ·
Sometimes the squirrel tracks in the snow are made by squirrels, and not rabbits on squirrel stilts. this is one of those occasions.

"but I cannot find sufficient detail in the shop manual of this junction area of oil and water circulation to confirm."

It's because one doesn't exist.

Why does this get tagged as "Radiator Water"? Is it green and sweet of ethylene glycol? If not, diurnal variation especially in the sun will cause condensation.

Drain the oil, run the engine. If there is a leak, there will be evidence enough in short order.

Sounds like Condensation to me, overthinking notwithstanding.
 
#9 ·
I am pleased at your interest in my curious little problem. Thank you.

I continue to conduct non-invasive inspection.

Mr.PDX280:

The chain galley was my first inspection, down to the front cover "sump"/sprocket chamber. There was no sign of any water nor it's residue or effects on the clean steel parts.

Nor did I find any corrosion/erosion when the pump was changed out shortly before parking it.

Today brought confirmation of my initial startled reaction when I pulled the sump plug. As all was collected into a drain container, it was an easy matter to separate out and collect the water; it is definitely radiator water, easily identified by its green cast and glycol odor. Just about 36oz. worth.

When added to the radiator drain, the recaptured water came to some 6qt. theoretically leaving some 4-5qt. unaccounted for. Unfortunately, I have forgotten if draining the rad. also drains the block/head, and if not, this would account for most of the difference.

Engine Auto part Automotive engine part Font Machine



OK, first attempt to attach an image.... re-sizing escapes me.

It's supposed to show the proximity of relative passages.

I admit that there does not seem to be any direct path to the sump, but maybe someone more familiar can point something out.

Again, thanks for looking in.
 
#10 ·
Field work is not theoretical, many times running the machine will be the most efficient fault-finding method there is, this is one of those times.

You can determine the origin in 30 minutes warm-up, or you can totally disassemble the engine to find the corroded head passage allowing the leakage.

Theory is great, but there are times you just have to run it and find the issue. 36 ounces is enough that it will manifest fairly quickly.

Then you can change the head gasket. Check the PH of your coolant, the stuff likely went acid. The corrosion happens near the dissimilar metals faster than like-like junctions. My bet is one of the head passages has corroded in the time and drained the head.
 
#11 ·
'More Water' is the internal bypass from the head to the inlet of the water pump. Racers plug it to allow full pump capacity to go to the cooling of the engine, and not recirculating the hottest water back to the inlet side of the pump.
 
#14 ·
Mr.pdx280:

Good question. The seals on the old pump had been leaking some, enough to paint a greenish stripe on the underside of the hood, for some time. I decided to change it when the opportunity allowed. There was no "Oh crap!" overheating moment.

And again, there is no forensic evidence that any water spent any time circulating with the oil. I am now quite confident that the accumulation I found in the sump got there since it was put in storage.

I just don't know how.
 
#16 ·
Starting the car will stop all this mental masturbation.

Some people like masturbating. I just don't fancy it in public unless I'm getting paid.
 
#17 · (Edited)


Heartland? What? "East of the Mississippi"... It sure as h e l l isn't MICHIGAN! They lost that title in the 1980's!

Japan surpassed US Prodcution in the 80's, China surpassed Japan in 2008.

Shite, MEXICO will surpass Japan as export leader into the USA likely soon! (Canada has generally always been #1 , but the UAW doesn't want to count that since they suck the fat off that piece of bacon to fatten their pockets!)

http://www.ibtimes.com/why-its-no-s...apan-become-no-2-new-auto-exporter-us-1557265

What I just love is this line:
"NAFTA has clearly helped the auto industry become a major economic force in the country – it’s now a greater source of state revenue than oil exports and remittances from migrants abroad – poverty continues to increase even as household incomes rise."

So Mexico now has the Automotive Industry overtaking Remittances AND OIL as a source of income....yet poverty flourishes. So much for that 'we made the middle class' argument on industrial production! The Government grows fat, and politicians profit from the taxes paid on PRODUCERS (that's corporations, not people, Marxists!) and nothing changes. HAHAHAHAHA!

America's Automotive Heartland? Dish me up some Beans and Rice and sit me down to a good old Heartland Fiesta, compadre... It's ain't happening in Novi on the shores of Walled Lake any more!!! Or maybe it's some Hushpuppies and Catfish with Fried Chicken down on the TVA Reserve...
 
#18 · (Edited)
Mr.D:

Clearly, a man of action and particular views. Whoda thunk my little exercise in deduction and crisis-avoidance would be a springboard for a fine political rant, and I'm sure we're all richer for the experience.

It's a question of personal style, I suppose, but I have never been fond of the "do it and see what happens" school of problem solving. Imagine the fun we would all be having if cars, buildings, bridges, and atomic bombs were designed this way.

Of course, if it's the doing it free part that bothers you, I could send you a check for your two cents worth.

As for myself, I'm not afraid to admit that I'm stumped; hence my address of this fine body of enthusiasts, willing to share knowledge, experience, and fellowship with other enthusiasts, without having to be patted down for provenance or mentally mugged just for the fun of it.

Or am I mistaken.

PS: The state of Indiana has been home to more marques of automobiles than any other state in the union. It is the Heartland.
 
#19 · (Edited)
I am known to digress...

And to correct discrepancies...

I did both in the last. You should have specified Indiana and not let it open to misinterpretation by others. I knew Michigan was not it, but others did not. I educated them.

It's not a matter of 'do it and see what happens' your incessant overthinking of the source of the water and postulation has proven fruitless.

If you are so set that you MUST disassemble the engine to find the source, you OBVIOUSLY have FAR more time on your hands than most adults.

My solution after your already exhaustive FRUITLESS investigation is to propose you can overthink this all you want...but you WON'T find the problem that way---as you have already proven!

Now is the time to turn it over and FIND THE SOURCE.


FYI: "cars, buildings, bridges, and atomic bombs were designed this way"

They WERE. That's the point most deskbound engineers forget. They postulated, but IN THE END, after all the thinking and postulating in the world...they had to DO IT to see if the calculations were correct. Many times they were at a loss to figure out why they were not.

A nice example exists outside the town of Terragona (sp?) Spain, where great Roman Acuaducts still exist. During a failure of a local Nuke Powerplant a piece needed to be transported to the plant from the local port. There were two bridges to choose from: One newly designed, with state of the art materials and a theoretic weight capacity far exceeding the weight of this heavy-lift replacement component. The other, a Roman Arch bridge still in use today, over 2,000 years old, but of absolutely unknown weight capacity.

The decision was made, for safety, to use the Roman Bridge.


All the fancy engineering in the world is useless when a practical expedient alternative is a known quantity and speeds up the process.

The Company Diesel Technologies in Grand Rapids existed solely to test nut stack configurations in Unit Injectors. Why? Because for all the calculations in the world, all the theory, when you put them in the REAL WORLD, some just didn't work. One of the most VALUABLE TOOLS they utilized were test technicians who spend thousands of hours a year assembling and testing these systems. Diesel Technologies valued their input, as many would make a suggestion about configuration which yielded results. You couldn't quantify why beforehand with calculations and theories, but not trying it because it didn't fit the calculations was not a way they operated. And as a result the invented and patented things other companies coveted. In fact, so much so that PCM Bosch bought their Commonrail Technology. But they were a German Company, and if the injectors didn't test the way they calculated, then the test must have been done wrong. Bad attitude, nonproductive. Move south were guys were less prone to argue and just do what they were told.

Problem solved. Development slowed.

The world doesn't run from behind a desk, on theory. It runs by running. You can vacillate all you want, try to understand it...but you are obviously missing the fact that everything you have checked proves no way for the glycol to get where it currently resides.

The two alternatives are:
Continue Postulating, and guessing, and disassembling something here and something there without a CLUE how or where it's coming from.

Start the vehicle, make PRODUCTIVE OBSERVATIONS, and then SOLVE THE PROBLEM.

As you will recall, Trinity Site was EXTENSIVELY INSTRUMENTED. If they knew what was going to happen, why instrument it? Perhaps to refine the calculations? That's called PRODUCTIVE OBSERVATION.

An equivalent to this situation is this:
Had The Manhattan Project Engineers took your stand, they would still be there, LOOKING AT the bomb they conceived, wondering if it would work.

Contrary to your postulation, they eventually realized that they have 'to do it and see what happens'---you will recall there was a question if this would ignite the atmosphere, and later with the H-Bombs crack the atoms of the Ocean.

They overcame their fears, they 'did it to see what happened' and then OBSERVED SCRUPULOUSLY the results.

The big thing here is your definitive postulations and hypotheses earlier will conclusively be found incorrect if you do this. Perhaps this is your fear....but inevitably, for lack of productive evidence elsewhere, this is, I propose, the ONLY practical avenue of continued investigation to conclude this matter.
 
#20 ·
I mean, I hate those Buckeye Bastards as much as any other guy...but in terms of GDP I think Indiana has always followed Ohio in terms of Automotive GDP. Maybe that changed recently with all the bailouts and closures.

Don't get stuck on what was, that was Detroit's Problem.

Nobody has sold Marmons for a long, long time!
 
#22 · (Edited)
Mr.D:

Whoa doagies! That was a real stem-winder. It wandered quite a bit, but hey, lay it on thick enough and no one will notice.

I will note only that in every case cited, the "action" finally taken was preceded by plenty of, as it turns out, productive and entirely appropriate "mental masturbation".

But more to the point (if it hasn't been lost by now) is that since the cause has proved invisible, the only thing to be learned by "doing it" is that damage will be the likely result, still without knowing why. By now, I'm sure you're very familiar with the adage "Act in haste, repent at your leisure."

Seems an unnecessarily risky way to treat an all-original Z to me. But maybe those who's cars you experiment with don't mind paying for your impatience or lack of imagination.

Oh, and I'm sure your worry about how I spend my time must have some relevance somehow... I just hate to see you "mentally masturbate" over it.

So anyway, I take it you're stumped too. It is a curious situation, isn't it. My thanks for thinking about it as much as you did. I'll have to owe you the two cents.

Anyone have something productive, or at least empathetic to offer?

Edit:

Dang! Two more posts while I was writing this. 39,588 posts, eh? Have any been on-point or helpful? Doesn't this fall under the category of "FAR more time on your hands than most adults."?

PS: If I'd been specific about Indiana's achievement, we'd all missed the fun of watching someone jump to some wild-ass conclusion.
 
#23 · (Edited)
THANK YOU!

The key there is PRODUCTIVE.

All your work thus far has been unproductive. You've exhausted or ignored/discounted the advice given and YOU remain stumped (others here await the startup to gloat, I'm sure!)

Now is the same juncture as mentioned: time to act, further machinations will accomplish nothing.

That you are so paralysed with fear over discovering the issue escapes me. I'm not stumped, I know what the issue is...you've already rationalised it away.

That leaves me in the position of "Oh yeah, start it and prove it!"

What HARM would happen? What catastrophic malady occur?

None!

At this point the most productive suggestion is "Quit overthinking this and start the d a m n e d thing, let it warm up, and SEE!"

This IS a valid technique. And honestly, throwing parts at it blindly without CLEAR EVIDENCE (as you seem so willing to do) is plain ignorant.

Time for less talk, more action. Solve it, quit talking about it!

It's no "stem winder" I'm merely competent at the keyboard and can talk and chew gum whilst walking simultaneously. It amuses me how you are wringing your hands making such a simple problem sooooo perilous and complex. It's laughable.


NOW REMEMBER PEOPLE: HE'S NOW ADDED THIS IS AN "ALL-ORIGINAL Z" (WITH 200K+ MILES ON IT) THAT SAT FOR YEARS AND IN NO WAY COULD HAVE ANYTHING WRONG WITH THE HEAD GASKET OR ALUMINIUM HEAD FROM ACIDIC COOLANT.

He's willing to disassemble the engine to find the source of the leak. But unwilling (despite his own stated admission that nothing is in ANY of the cylinders) to start the vehicle and run it up to temperature to visually detect the point of leakage....

You guys figure out whose crazier here, the guy petrified with fear, or the guy who thinks this is no big deal, and that nothing more will be achieved through further grasping at wild straws.

Figure out where it's leaking (you have already been told by several) and the "why" will be revealed when you replace the defective part (instead of a succession of parts guessing...)
 
#24 ·
Being here since 1999 lends itself to a post count that's up there.
That it's a problem for you is telling...

For the record, my "experiments" with the Nissan L-Series have netted 17 SCTA, FIA & Other Sanctioning Bodies World Land Speed Records.

I think I got the basics of the engine's mechanical structure down better than most, and undoubtably far better than you do given your ludicrous fears as stated in your last post.

Those who let me "experiment" on their rides have done so in excess of 170 mph on land, 100 knots on water, and prior to that Mach 3+ In the air.

Yeah, I know what "keeps 'em flying". I wish you did.
 
#25 ·
Oh, and FYI, A 78 280Z is no great shakes...it's nothing special. It's you inflating the value because of your ignorance of the marque.

Odd since apparently you have been lurking since 2009...
 
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