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Thread: Oil in Coolant Different (I promise) Reply to Thread
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  Topic Review (Newest First)
02-29-2020 06:04 PM
MSattler Thank you for the response. With all of the repairs to the pawl spring, Iíve drained the oil several times already. Luckily it was just oil, even the first time I changed the oil after sitting for 20 years. I am hoping itís not a head gasket, but doesnít overheating become a problem with the head gasket? Could it just be residual old coolant that is being worked loose as everything heats back up? It seemed to get less and less with the two or three flushed last summer

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02-29-2020 04:44 PM
VN750Rider/Jerry Mechanical things like motorcycles don't take well to sitting. Things that were made to move need to be moved. Otherwise they quickly start to deteriorate. Iron and steel rust, aluminum and brass corrode, rubber and plastic rot. Seals dry out and crack, rings rust in the cylinder bores, moisture condenses inside things and speeds up the rust/corrosion process. Oil and coolant mixed together make glue, which plugs everything up. I would drain the oil and the coolant, flush the cooling system as best you can with distilled water only (NO automotive flushing chemicals) put in new oil and distilled water only. NO ethylene glycol. If the engine runs, it is important to prevent plugging of the oil passages. The two most likely places coolant and oil can mix are a blown head gasket (either cylinder or both) or the mechanical seal in the water pump. I think someone here had that problem not long ago. Are you sure there is no coolant in the oil? it would show up as a milky white substance in the oil sight window. However, simple water condensation in the oil can look the same, but it quickly burns off. Cracked coolant reservoirs are not uncommon. I've been through at least 4 of them on 2 bought new Vulcan 750s.
02-28-2020 11:52 AM
Oil in Coolant Different (I promise)

So I just purchased about $800 in parts to get the Kawasaki back on the road, after I laid it down going 5mph, due to original tires. I am worried that I could be wasting all of these parts, though. It is an 86 that had sat for at least 20 years, before I picked it up for $300. The fluids had sat for that long, so almost everything looked like oil (brake fluid, coolant... even the oil looked like oil!). The bike never got hotter than the normal range, but before I flushed the coolant, I had noticed that the reservoir looked like it was full of pus colored oil. It took two attempts to get all of the sludge out of the engine coolant weep holes, but I finally got the drains on the block to drain. Again, it was full of white pus colored sludge. I flushed the system a couple of more times, and the reservoir looks better, but the new coolant still looks kind of milky. Again, it never got anywhere overheating, despite city driving in August. When I took off a couple of the coolant lines, they were milky as well. I cleaned the metal parts, but I left the original hoses on. I will go to auto zone and pick up some new hoses, but the fact that the milky sludge is still in the tank is concerning. A couple of key notes; the metal pipe that goes to the rear cylinder on the left side of the bike leaks coolant (small dribble), and the second bolt on the head towards the rear of the bike on the first cylinder leaks oil. I bought some black rtv to seal that up once it gets warmer, before painting the engine. Iím wondering if this is a concern, since the temperature seems unaffected. There is not coolant in the oil, however. Thoughts? Any advice would be great

PS - The coolant reservoir is also cracked, if anyone has a spare for purchase!

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