Coolant - How often do you top up?

Hello All,

Still new to these big engines (big to me).

1. How frequently to you check coolant level?
2. How frequently do you need to top up and how much at a time?

I check the levels about every other start-up.

I've used a gallon of coolant topping up since last October (2014) and have probably run the engines about 40 hours.

Side question: Is literally two drops of oil from an engine over 5 hours of running a cause for concern? I have a spotless white drip pan and check every time. This is only one of the engines.

. How frequently to you check coolant level?

After every shut down , to be ready for next engine operation.

2. How frequently do you need to top up and how much at a time?

Every couple of years , usually just when the system is 2 part flushed and new AF installed to gain anti corrosion additives.

tegdesign said:

1. How frequently to you check coolant level?
2. How frequently do you need to top up and how much at a time?

Side question: Is literally two drops of oil from an engine over 5 hours of running a cause for concern? I have a spotless white drip pan and check every time. This is only one of the engines.

Click to expand...

After the engine room cools from a run.

Hmmm.... never?

Yes. Better to diagnose and fix (if necessary) at the "two-drop" stage. OTOH, could be something simple, like a drop from the dipstick that migrated it's way down the block, after having checked the oil sometime in the recent past.

-Chris

I used to check coolant and oil every time before start-up. Most especially when a long day of running was ahead. That is the biggest threat to diesels, overheating. As for the leaks. You didn't mention what the engine make was, but our old Perkins was like a 70's Harley... As they said, "If it's not leaking oil, it's out of oil." After a good long steam, there were small spots on the under-engine diaper by the front and rear seals, and sometimes a fuel spot from the injector pump. None large enough to cause concern for the average Perkins owner

If you have added a gallon since last October, there is a leak.

Ted

On my "ex" a Cummins 6BTA, I never had to add any except at coolant change time.
On my current Ford-Lehman, I maybe top off once during the season now that I found and fixed the tiny leak I had.
I usually do a visual ER inspection the morning before a run. (I avoid crawling in a hot ER if I don't have to)


2 drop of oil after a 5 hour run is likely not a cause for concern, HOWEVER I would try to find the source. If something simple (like a valve cover gasket), I'd fix it. If something more involved (such a main seal) I would monitor.

Always checked levels before running. The on engine tank itself, not the expansion tank. In reality the only time I added was when we flushed them every couple of years. A gallon does indicate something is up. Get the oil analysed as coolant in the oil is bad news unless addressed immediately.

Coolant - How often to you top up?

Ditto. Always remove the cap for checks. Get some ph test strips as well and check acidity every 6 months. Sounds like you either have a leak or a pretty big air bubble in the system. 5 hours is barely enough time to get everything heat soaked so I wouldn't worry about a few drops of oil yet.


Via iPhone.

Greetings,
Mr. te. Every morning before start-up I do an ER check. Twin Lehman.
Engine oil, transmission fluid, AF (translucent overflow tank, so just a visual), belt tension. Onan 15kw generator. Oil level and AF expansion tank level, belt tension.
I do have nagging oil seepage as evidenced by spotting on the diapers in the drip pans, primarily on the stb'd engine after a days running. I've attempted to visually source these leaks/seepage to no avail. Soooo....I've purchased a product similar to this: Tracer Products Leak Finder TP8621 - Leak Detection Kit | O'Reilly Auto Parts
Will do a diagnosis in the future...

I check all fluids before the 1st run of the day, every time I use the boat. I have never had to top up the coolant.

Sometimes after flushing the coolant you need to top off a bit as the system purges air out, shouldn't need to continually top off, I mark my over flow (cold and hot), so usually give a look while underway and then the next morning when I do oil and visual checks, like others have said depends on the runs, short weekend runs I check at the end.

Oil drop, just go around with a white rag and see if you can find the origin, might take some time.

tegdesign said:

Hello All,

Still new to these big engines (big to me).

1. How frequently to you check coolant level?
2. How frequently do you need to top up and how much at a time?

I check the levels about every other start-up.

I've used a gallon of coolant topping up since last October (2014) and have probably run the engines about 40 hours.

Side question: Is literally two drops of oil from an engine over 5 hours of running a cause for concern? I have a spotless white drip pan and check every time. This is only one of the engines.

Click to expand...

Check the coolant level by opening any engine mounted petcock air bleeders you may have. The coolant level in the expansion tank on must engines should stay about an inch or so below the top when cold to allow for expansion. Trying to keep it filled to the tippy top all the time just wastes coolant. Also make sure any hose connection between your over flow tank, if you have one, is clear.

As to the oil drops, I wouldn't worry about them. But try to find their source and stop it.

Some older engines are not meant to be full of coolant. Like autos b/4 coolant recovery bottles, when you checked the water, if you could touch it with your finger, you were good. Any you added above this point would be pushed out the overflow and wasted anyway.
With the advent of recovery bottles this overflow is drawn back in each time the engine cools.
So, if you have no recovery bottle, your coolant level should always be down an inch or so when the engine is cool. This allows for expansion when hot.

I always forget the signature line doesn't show on mobile devices. My engine spec it there, but FYI for those interested:

1987 Volvo TMD41A

I was taught by an old time mechanic not to trust the overflow tank as a gauge of your coolant level. He had seen too many instances of the little hose getting kinked, even clogged.

caltexflanc said:

I was taught by an old time mechanic not to trust the overflow tank as a gauge of your coolant level. He had seen too many instances of the little hose getting kinked, even clogged.

Click to expand...

I was lucky when it happened to me.

Before start up for the day.
Lehman 120 owners with original tank fillers (and probably original caps), if you constantly lose overflow coolant, new tank caps may fix it. Springs and seals deteriorate.

BruceK said:

Before start up for the day.
Lehman 120 owners with original tank fillers (and probably original caps), if you constantly lose overflow coolant, new tank caps may fix it. Springs and seals deteriorate.

Click to expand...

Good idea. Thanks!

Note to self - replace coolant reservoir caps...just in case!

Caps hardly cost anything, but check there are different sizes. And you`ll have trouble getting the low psi specified caps at auto shops, mine are from AD.

RT Firefly said:

Greetings,
Mr. te. Every morning before start-up I do an ER check. Twin Lehman.
Engine oil, transmission fluid, AF (translucent overflow tank, so just a visual), belt tension. Onan 15kw generator. Oil level and AF expansion tank level, belt tension.
I do have nagging oil seepage as evidenced by spotting on the diapers in the drip pans, primarily on the stb'd engine after a days running. I've attempted to visually source these leaks/seepage to no avail. Soooo....I've purchased a product similar to this: Tracer Products Leak Finder TP8621 - Leak Detection Kit | O'Reilly Auto Parts
Will do a diagnosis in the future...

Click to expand...

RT - Leak finder seems interesting. Please keep us briefed! - TY, Art

Greetings,
Mr. A. Will do but it won't be for a while. We're home and the boat is not and we don't anticipate visiting for some time. I might add they have tracers for engine oil, transmission fluid, coolants (Anti-Freeze) and AC systems. Evidently, NOT an uncommon analysis tool...

Perhaps a better question would be "how often should I change my cooling fluid".

I don't have a surge tank. My exhaust manifold usually has a head exchanger inside but I installed mine on a bulkhead just aft of the engine. My cooling system is then more like an old car where the top of the radiator serves as an expansion tank. In my case it's the exhaust manifold upper tank. There is more coolant of course because the heat exchanger is missing. The idea behind the surge tank is/was to keep air from coming in contact w the coolant. I don't think it makes much difference but it may be of some help. The engine manufacturer strongly recommends LLC for coolant mixed 30% to about 70%. I've read 40% is optimum not considering freezing. I'm missing my manual but I'm almost sure it says to change coolant every three years. I think the green stuff (not long life) is intended to be changed every year .. or maybe two. I think LLC is mostly for corrosion resistance when aluminum parts are in contact w the coolant.

"Perhaps a better question would be "how often should I change my cooling fluid".

The cheap green stuff 3 years .

With a 2 part cleaner and flush flush flush.

Only distilled water should be added when filling.

FF said:

"Perhaps a better question would be "how often should I change my cooling fluid".

The cheap green stuff 3 years .

With a 2 part cleaner and flush flush flush.

Only distilled water should be added when filling.

Click to expand...

Interesting statement. I've always used good clean tap water mixed appropriate to climate conditions with quality antifreeze for cooling system in motors of any type. Can see how distilled might have advantages. But I wonder... is there anything living, microbe or other entity, in clear tap water that could flourish in a cooling mix containing large %age of antifreeze??

I can see why and always use distilled water for wet batteries... but, with antifreeze? I'm anxious to learn reasons why you feel that may be better for cooling system use.

BruceK said:

Before start up for the day.
Lehman 120 owners with original tank fillers (and probably original caps), if you constantly lose overflow coolant, new tank caps may fix it. Springs and seals deteriorate.

Click to expand...

You should also bleed the air out of the engine at the top mounted petcock.

I always used tap water too. But I also used motor fleet (truck) coolant, never the green stuff, and changed it every spring since the motor was nearly 30 years old.

re: 2 drops of oil

I have the same engines Occasionally, after an oil change, I have dribbled a little oil on the valve covers when filling. I usually have a cloth handy and always wipe up all that I can see. sometimes, however, a few drips have gone into hiding and re-emerge to drip from the low points at a later time. This may be your source.

Many places tap water is high in mineral content...distilled is recommended but if your tap water is pretty pure and the engine isn't high performance...like most things in life will your engine know or care?

Same with antifreeze...American diesel said just use the cheapo green stuff, everything else is a waste of money...better to change frequently like oil....any antifreeze can become contaminated

But...many diesels need specific fluids best to stick with them...unless the manufacturer can't justify the difference.

I've used distilled water since I can remember but I'm curious about the special AF for diesels. I forgot about that and just bought regular extended life AF. Since I don't have any aluminum in contact w my coolant perhaps I don't need LLC and perhaps Amercan Diesel's recomendation to just use green is applicable to me.

Misplaced my manuals but I think it recommends LLC for my S4L2 Mitsubishi.