Sea Water and Oil - How Much is Too Much for an Engine (2QM20)!

[Wotname]

Originally Posted by Compass790

.....
Did you try a drift & hammer on your v/v guides?

Ahh... no - should I?
Was gunna leave that to the engine shop man - thinking that I would be doing more damage than good with stuff where I have zero experience - not that has stopped me in the past

[Compass790]

Well they are an interference fit so I would normally use a press but for the YSM8 it shows a "special tool" that you can buy from the yanmar agent for a kings ransom ( basically a 7mm pin punch ) to be used with a hammer for removing v/v guides.
I was just curious to know if you tried it. FYI you can buy a reamer for not much from alislow if you want to install new guides yourself.

[OloteleMtn]

As a retired professional mechanic, I can't say i approve of all of your methods, but it is amazing what can run even when out of specs. Your water intrusion problem may have been caused by a failed oil seal on the water pump">raw water pump, allowing sea water into the block via the camshaft.....keep us posted.

[JPA Cate]

good to hear someone somewhere is reading this

Actually, it's on my "must read" list. Possibly a bizarre interest for a little old lady, but...there you go!

Ann

[Jim Cate]

Originally Posted by JPA Cate

Actually, it's on my "must read" list. Possibly a bizarre interest for a little old lady, but...there you go!

Ann

And people ask me why I married her!

Jim

[Wotname]

Originally Posted by OloteleMtn

As a retired professional mechanic, I can't say i approve of all of your methods, but it is amazing what can run even when out of specs. Your water intrusion problem may have been caused by a failed oil seal on the raw water pump, allowing sea water into the block via the camshaft.....keep us posted.

Yes, that possibility was an initial consideration. The RW pump was incomplete and in parts when I got the engine which sort of supported that view however an internal inspection of the PTO end of the engine did not show much corrosion. Maybe I will never know for sure.

As for my methods, heck even I don't approve of all of them . If there is something that is particularly egregious to you (or others), please feel free to shout out! My skin is thick(ish) . Rest assured I am more pedantic when it comes to the re-assembly work.

[Reefmagnet]

Originally Posted by Wotname

Yes, that possibility was an initial consideration. The RW pump was incomplete and in parts when I got the engine which sort of supported that view however an internal inspection of the PTO end of the engine did not show much corrosion. Maybe I will never know for sure.

As for my methods, heck even I don't approve of all of them . If there is something that is particularly egregious to you (or others), please feel free to shout out! My skin is thick(ish) . Rest assured I am more pedantic when it comes to the re-assembly work.

If it helps, this is what you could expect to see. This is what the end of the PTO driving a dud r/w pump looks like...

[Wotname]

The next stage is take the liners, crankshaft and head to the engine machine shop for a professional measure and inspection. That will happen next week and at this stage I am unsure how long before I know more.

In the meantime perhaps any professional mechanic (or other knowledgeable people) can answer the following question.

Generally speaking engine wise, is mechanical wear linear? For instance, say an item (piston etc) has a wear limit of 10 thou and it measures at 5 thou, is it half way through it's life assuming similar operating conditions?

Put another way, does the first 5 thou wear faster or slower or at the same rate as the next 5 thou?

I have always assumed it was linear but I realise this is just an assumption on my part and maybe I should ask the question!

[GILow]

Originally Posted by Jim Cate

And people ask me why I married her!



Jim

Actually, most of us are wondering why she married YOU.

[GILow]

Originally Posted by Wotname

.. That will happen next week and at this stage I am unsure how long before I know more.

...

Get your skates on mate... I’m expecting a ride in this bucket when they eventually lift the inter-state travel restrictions.

P.S. that initial sump picture looked a lot like my bath water.

[Compass790]

Generally speaking engine wise, is mechanical wear linear? For instance, say an item (piston etc) has a wear limit of 10 thou and it measures at 5 thou, is it half way through it's life assuming similar operating conditions?

Put another way, does the first 5 thou wear faster or slower or at the same rate as the next 5 thou?

I have always assumed it was linear but I realise this is just an assumption on my part and maybe I should ask the question![/QUOTE

Good thinking Wottie not to make the assumption.
According to a very experienced, well regarded machinist cobber it's not linear. In his words "wear is a funny thing, you get none for a long time & then it gets to a point where it starts accelerating"
I take what he says seriously as he has pointed out the flaws in my Baldrick plans before. I always prefer a study to hearsay so hopefully someone chimes in with one.
I assume, with increasing clearances, the wear rate should increase as imagine a piston flopping back & forth in a cylinder. The smaller the piston diameter gets the bigger the impact when it contacts the cylinder walls. But that's just an idea, need proof.
Following with interest.

[Jim Cate]

Interesting question, wottie!

Another way of looking at it is that as the engine wears, the power output is lessened, and thus the loads on everything are lessened (I think). But then, some surfaces, crank journals for one, are surface hardened. When that thin layer is broached (breeched?) the wear rate will indeed accelerate. And exhaust valves... once t hey begin to leak at all, the wear (or erosion) rate goes up dramatically.

So, I suspect that wear rates as a function of time or fraction of tolerance are not the same for all parts of an engine. How's that for equivocation???

Jim

[Wotname]

Originally Posted by GILow

......

P.S. that initial sump picture looked a lot like my bath water.

You channelling Cleopatra...???

I have been warned about Croweaters

[Wotname]

Originally Posted by GILow

Actually, most of us are wondering why she married YOU.

The quintessential unfathomable existential question .

Ya a deep thinker Matt!

[GILow]

Originally Posted by Wotname

The quintessential unfathomable existential question .



Ya a deep thinker Matt!

Gotta do something in my bath of crow’s milk.