Need Help Rusty bits in the coolant

[MrMogensen]

Was in the middle of disassembly to check the valve clearance, when I had the horrific discovery of the coolant looking very brown. First I thought it was oil, but then again I didn't notice any sign of coolant in that?
Found lots and lots of small bits of what could be rust in the coolant so that could explain the brownish color. I thoughr that it was the coolant system was all rubber and alloy?

Have removed the water pump cover as the bit of it covered by he big hose looked quite corroded. Inside the tube I could scrape out a thin layer of brown goo (rust)?
Some other day soon (when I have time) I will maybe take out the waterpump itself to inspect it.
Radiator also removed since I need to flush it. Looks all brown on the inside. Would like to flush out the whole system if possible. Maybe just water first and then flush with distilled water?

*What is the most likely cause of this - rust in my collant?
*Whats the best way of flushing? Will water run through the pump when the pump isn’t running?

Must admit it is nearly 6 years since I drained the coolant (last time I did the valve clearance check). The coolant I used was some "hybrid" ready to use stuff - dealer recommended it. I have the same kind in stock again.

***
Valve clearance was, on 14 measuring points spot on right in the middle of spec. The remaining 2 was just about spec (maybe 0,01mm above) so decided to leave the camshafts on and focus on the other issue.
Pulled off the generator cover. In my 14 years with the bike i have never done this. The cover shows more alloy than paint (a decade of stonechips) so it's about time to get it painted. Same thing with the pickup rotor cover on the other side.

 

[TownsendsFJR1300]

There's very little steel in the system.. I can think only of the impeller itself being steel, the shaft it rides on, T-stat, radiator pressure cap, ..

Re flushing, I'd shoot a garden hose thru the radiator, hoses, etc. I would also pull the lower hose off the cover (you already have the WP cover off) to flush...

To remove the impeller now, there's no reason to, you can see it.

With that corrosion showing on the aluminum, (where the hose goes over), I'd remove all hoses and just clean up where's there's likely corrosion there as well..

Once you get out as much "goo", I'd fill it up, run with distilled water. Then fill with the proper coolant...

 

[MrMogensen]

Thanks Townswend!

What about the oilcooler down at the front - maybe steel in that? Since oil is also drained would I make sense to disassemble that?

Good tip with initial startup only with distilled water. When I have had so many extra hoses off/on it's likely I will have some leaks here and there - can be fixed before real coolant is added.

 

[TownsendsFJR1300]

Re the oil cooler, can't hurt to pull the hoses (should anyway to clean the connections) and peek..

You just want to get that corrosion off where ever rubber hoses attach to the block.

BTW, I've never heard of an FZ6 oil cooler failing in anyway.

I'd think once cleaned and new coolant, it should be fine..

 

[Motogiro]

Also if you suspect the bits are rust they should stick to a magnet..

 

[MrMogensen]

Also if you suspect the bits are rust they should stick to a magnet..

It's itty bitty pieces - it's the worst trying to clean a magnet of very small pieces of metal particles, but then again I want it gone (at much af possible).
Hmm maybe I should drop af magnet in the reservoir when doing the initial startup with distilled water.

 

[TownsendsFJR1300]

If it is rusty steel (or otherwise), it won't "attract" to the aluminum block.

I'd just flush the heck out of it with the garden hose, then with distilled, then with coolant.

 

[MrMogensen]

Surely! The magnet was just an extra...
Still going for the plan you recommended.

 

[pmmcanon]

Did you check the PH of the exisiting liquid? When they are not the proper one or are lasting for long time they tend to acidify themselves causing corrosion on other materials too. The correct PH level should be alcaline, around 9. If this is the case, there are some alcaline cleaning fluids to clean and remove rests of corrosion.
Hope it helps

 

[MrMogensen]

Did you check the PH of the exisiting liquid?…

If this is the case, there are some alcaline cleaning fluids to clean and remove rests of corrosion.

No I didn’t think to check cause I only thought “some part is rusty”. Highly likely since draining the old coolant was overdue.

 

[MrMogensen]

Update
Look what was a the bottom of the coolant reservoir. Let’s just say it looks like Nutella and not something else
Don’t have to look for something that’s rusty now. It IS the coolant that started to transform into acid sludge. Big cleaning job due… would have been a bit faster to change the coolant every 2nd-4th year.

 

[Gary in NJ]

Wow. I’ve never seen that type of corrosion in a motorcycle before.

 

[MrMogensen]

Wow. I’ve never seen that type of corrosion in a motorcycle before.

Most of it is just easy to scrape away or wipe with some cleaner. On the outside of hose connections (air contact) it’s worse. Unlucky combo of (maybe) not long lasting coolant and 6x 8-9 month seasons. In my head I was waiting to change the coolant till it made sense with next valve check clearance check. Bad decision…

 

[TownsendsFJR1300]

Wow. I’ve never seen that type of corrosion in a motorcycle before.

Looking for a first car for my nephew about 2 weeks ago, found one Chrysler LaBaron with that
sludge (not as thick), just inside the radiator... It had other major issues as well so no sale...

 

[Gary in NJ]

Wouldn’t that sludge be a sign of oil in the coolant? I would do a leak down compression test and see if any bubbles appear in the cooling system.

I generally do a leak down test at 80 psi, but for this one I’d go to 100 psi.

 

[MrMogensen]

Wouldn’t that sludge be a sign of oil in the coolant? I would do a leak down compression test and see if any bubbles appear in the cooling system.

I generally do a leak down test at 80 psi, but for this one I’d go to 100 psi.

Have never felt the need to do a compression test before as it was previously very clear, in a former older car, that the headgasket was finished. So I have to ask...
How do I best perform this particular compression test? A cylinder compression test wouldn't really give me anything (I guess). I guess I would need to assemble almost everything, fill up with oil and coolant (maybe just water for testing)? And then…?

 

[TownsendsFJR1300]

Did you have loss of coolant or coolant leaking into the oil?

How do the spark plugs look?

How's the bike run?

If the machine passes the above questions, I don't think you have an issue.

If a blown head gasket, a leak down test would show that (bubbles blowing into the coolant system).

 

[Gary in NJ]

You mentioned that you have rust in the coolant. Do you have any photos of that? That blob of sludge is oil. It’s not rust because rust is iron, and that blob isn’t iron. A head gasket failure isn’t always bidirectional. A differential compression test (aka a leak-down test) is not a compression test that checks total compression, but how/where you are loosing compression. You basically look or listen for signs of air escaping from the tested cylinder.

The test is performed on each cylinder separately. During the test the tested cylinder is held at TDC with a wrench on the crank. Air is introduced into the cylinder at a known psi (the reference psi) and is compared to tested psi - hence differential. 80% is typically a passing grade, especially on a cold engine.

 

[MrMogensen]

Townsend =>

Bike is at my dad-in-laws garage so can’t as easily go to it…

Oil looked fine - well it was brown and used but didn’t look like coolant was in it. Then again the coolant was also brownish and I thought it was rust (and acid old).

Unfortunately I haven’t yet pulled the spark plugs as I didn’t think about oil leakage. Will report back about that.

Bike ran fine after I gave it wash and rode the last 10 km to winter storage in November. Haven’t had any issues if power loss or uneven idle. At least none I noticed.

 

[MrMogensen]

You mentioned that you have rust in the coolant. Do you have any photos of that? That blob of sludge is oil. It’s not rust because rust is iron, and that blob isn’t iron. A head gasket failure isn’t always bidirectional. A differential compression test (aka a leak-down test) is not a compression test that checks total compression, but how/where you are loosing compression. You basically look or listen for signs of air escaping from the tested cylinder.

The test is performed on each cylinder separately. During the test the tested cylinder is held at TDC with a wrench on the crank. Air is introduced into the cylinder at a known psi (the reference psi) and is compared to tested psi - hence differential. 80% is typically a passing grade, especially on a cold engine.

Picture attached!
If I only have a leak between oil and coolant will the leak-down test tell me anything?
Please explain the reference to test pressure? It’s not just a cauge to the cylinder is it?