4 replies to this topic

[amsgw]

Hi all, rebuilt 1293 in August last year. Went to all the correct lengths...apart from setting the primary gear tolerances correctly, so the engine did ~ 50 miles before she's been pulled out again to sort that plus a couple of oil leaks (sod you, Hylomar)

There was no evidence of dreaded milkshake but on draining the oil (this would be the 3rd oil change since the engine came to life) there are what looks to be the smallest neon pinkish swirls sitting on the oil surface (disappearing after the oils sat), and there is the beginnings of creamy sludge on the inside of the rocker cover and some that seem 'caught' on 2 of the rocker bolts. The oil leak on the ground under the timing cover looks pretty creamy, but this is also right under the purge hose for the coolant. Inside the rocker cover, the assembly looks 'wet' with water drops suggesting condensation but no pink. No other evidence of issues though.

So the question is, how soon would there be enough coolant mixing to show up as creamy oil? I could really do without having to do the head gasket again but equally would rather do it with the engine out & avoid further running in on a crap oil mix

Also, is there a modern adapter that allows to pressurise the cooling system? I've seen them for newer engines etc. but not sure how it would work with the purge hose or whether the caps would fit?

Important notes - the coolant is hot pink, very visible. It's leaking slightly from the thermostat housing (did I mention I now hate Hylomar?). Both head and block were skimmed in the rebuild and high quality HG used. Studs were retorqued accordingly during the beginnings of the running in, no signs of overheating etc. I'll be benchtesting the engine out of the bay so will run another compression test then too, compression tests when the engine was first dropped in were all spot on at 10bar. I don't have an expansion tank for the coolant.

[amsgw]

I should say, tool to pressure test** the cooling system

[nicklouse]

Milkshake/sludge is normally due to lack of getting the car to temp and using it and incorrect breather connection. It is nothing to do with coolant in the oil. That would be seen in the oil when changing it or on the dip stick.

[amsgw]

I would agree except the engine had hardly been run at all, and had gotten up to optimal temp several times so whatever small buildup would have been cleared then, and also doesn't explain the swirls. Dipstick was clean though!

[Spider]

The oil goes creamy quite quickly, though before jumping in to anything else, as Nick suggested, it may well be that the oil's 'wet' from the atmosphere and needs drying out. They do need a decent long run to do that as it takes quite a long way to heat the oil to running temperature and it needs to be held there for up to an hour.

The other thing is the crankcase breathers all connected up correctly and a vented oil filler cap on it ?