Dreaded oil and coolant water mix! guidance required please

[coolexperts]

Hi there,

See if you can find a garage with a co2 tester. This is normally a glass tube with a one way valve at the bottom and rubber bulb at the top. It is filled with a magic blue dye that turns green then yellow in the worst cases. The one way valve end of the tube is held over the rad filler neck and with the engine running the rubber bulb is squeezed to take an air sample off the rad. If the head gasket is leaking you should find exhaust fumes in the water jacket as well as oil in the water.
Did you make sure the system was bled and no air was trapped in the engine behind the thermostat. If you take the top heater hose off and fill the rad with coolant until it comes out of the heater and disconnected hose you will know that the system is air free.
As a previous member said your milk could be from fuel going down the side of cold new piston rings as well condensation.
I wish you well!!

Steve AKA Mr cool

[gazzamuffin]

Hi all,

just an update on the oil / water mix.

I took of the cam cover to find out how much m"mayo" was in the cam cover. (see pics)

Checked dip stick and couldnt see any mayo on it

Not sure if the qty indicates anything (comments welcome)

so i tried to pressure test the radiator system using a home made test rig. I got the pressure upto 0.5 bar ( around 7 psi)

could not see any leak from water pump area or see / hear any leaking from anywhere else.

So, i cleaned it all up and re-fitted the cam cover.

Checked rad water level and started the engine.

Got it up to a temp of around 80C then switched off.

I let it all cool and checked water level, No change there

checked inside cam cover, a little mayo but not much at all.

so, not sure if i have a problem or not.

any points of view??

[CBUEB1771]

Got it up to a temp of around 80C then switched off.

I am not sure that you are assimilating the responses to your original post. If the starting engine and ambient temperatures are low and you idle until the coolant reaches 80 C you are likely to find oil/water vapor foam. If you drive for an hour and get the coolant to 100 C for 30 minutes you should not see foam.

[robertverhey]

Take it for a good, decent sized, brisk run, with an eye on the temp gauge.

[m750rider]

There is more than I would expect to see but I would drive it for at least an hour or so and get the oil temperature up where it belongs.

Bob
1969 S4

[rgh0]

From the description of what you have done so far it does not appear you have done anything yet to bed in your piston rings. Until this is done you will have large amounts of blow by past the rings and lots of water condensing in the oil and cuasing the Mayo you see. if you are using synthetic oil this will increase the mayo forming tendency also I believe.

You need to load then engine to bed in the rings as described in other posts. If you still have mayo after that then I would worry about an oil / water leak.

cheers
Rohan

[gazzamuffin]

Hi all !

A BIG !!! thanks for the replies !

it is reassuring to read what you have said.

I shall take it for a decent run and then take another look.

thanks once again !!!

Gazzamuffin

[0005K]

My engine block and head were rebuilt 43 years ago and reassembled (with oil but no coolant) but not run until a few weeks ago. During the original reassembly, I installed a new OE water pump. I was pleasantly surprised to find that it does run now. It still has not seen the highway.
After covering my garage floor in oil from an oil line failure, I replaced the oil line and oil and ran it for about 20 minutes. Oil pressure at around 40 psi at 1000 rpm. It was running at 212 but no steam or leaks were seen. Coolant was leaking from a split recovery bottle, so I let it cool overnight and topped the coolant off the next morning. It took a lot of coolant. I checked the dipstick before restarting and the oil sump was over-full. I thought I might have over filled it when I replaced the oil line, so I drained off some from the sump. What came out was coolant! I have not tried to restart it.
I assume that at a minimum, after draining the sump and removing the oil filter, I will need to pull the head and replace the head gasket. I am hoping that I do not need to replace the water pump, as that requires pulling the block also. I expect the cam cover will show milky oil covering the inside. I hope it is from a leak at the the head gasket. Is there a way to confirm the water pump is still OK? What else should I look for?
Dick

[2cams70]

Looks like a fair amount of Mayo on the inside of that cover to me. When you take it for another run make sure you stop to check the coolant level frequently and oil level for that matter - it will rise if coolant is leaking internally into the oil pan. Don’t just rely on the temperature gauge because once the temperature sensing bulb is uncovered of coolant it won’t be registering the correct temperature - it will be reading lower than the engine temperature actually is. Don’t forget to take a jerry can of water with you. The transition from a little overheating to very hot and engine damage is very fast if there is loss of coolant. Don’t be tempted to drive just that little bit further home. Stop straight away and top it up!

[Pfreen]

I personally would not drive it hard, idle only. I have done a lot of work on development/experimental engines on dynos and water in the oil causes scuffing of cylinder walls and bearings very quickly, which would require a complete rebuild again.

1st, change the oil and filter. Then proceed carefully.

There are kits available to test for combustion gas in the coolant which will tell if you have a head gasket leak. Your coolant pressure test is good but I would do it with the engine warm.

In my 45 year engine R&D career, I have never seen that much cream in the oil without something wrong and running it hard isn't going to fix it.

My 2 cents worth.

[0005K]

2cams70 & Pfreen
Thanks for the reply. The pictures are from 2012 - not mine....but very close to what mine looks like. Lots of Mayo underneath the cam cover. I had a large quantity of coolant in my sump. Draining it last night also drained part of the radiator. The water pump does not feel loose or "lumpy" when turned. Is there a way to confirm that it was the head gasket and not the water pump which filled the sump with coolant?
I'm now in the process of disassembly. Alternator belt off. Carbs are off. Upper rad hose, heater control and heater hose removed. Exhaust manifold brass nuts are off. More to go.
I have reviewed "Head Removal & Replacement for Dummies" on this forum. I am hoping to remove the head leaving the block in the car. I am awaiting removal, before I order a new head gasket, as there may be other items needed. The engine has less than one hour on it, so I am hoping the issue was a reassembly/ head-torque error I made years ago, and that no other damage was done.
Thanks,
Dick

[ncm]

Dick, It is possible for coolant to escape from the joint between the two halves of the timing chest where the water pump fits if the mating surfaces are not perfectly flat as there is no gasket between the two. It is possible to see the joint if you look down the front of the head where the chain runs.
Brian.

[0005K]

Brian - Thanks for the input.
I can barely see some of the joint around the water pump front plate to back plate you are talking about - with the head and cam sprockets in place. I'll try refilling the radiator and turning the pump by hand to see if I can see it drip. I'll try re-filling and turning it again after pulling the head so I can potentially see the joint better. Either way the head has to come off I think.
If it leaks from the joint between the plates, the timing chest has to come apart and be re-installed, and I think that also requires dropping the sump - which requires pulling the block. I don't think I can remove the front attachments for the sump and split the halves of the timing chest. But I may attempt that before pulling the block, if I find the timing chest is a source of the coolant leak. This water pump and timing chest has seen only about 20 minutes running time since rebuild (43 years ago!), so it may not be corroded together as much as normal.
I'm hoping I don't see any evidence of that joint leaking, so I can just replace the head gasket, after insuring that the head has not warped.
Dick

[0005K]

Head did not appear to be cracked or warped, but not taken to a machine shop. New composite head gasket. New head to block rubber oil tube. Torqued it all up, put on the sprockets and chain, and reconnected cooling system. Still at #1TDC. Oil still out with drain plug removed. Raised the front end so that the radiator fill tube for cap is higher than head. Added water. Water is dripping from the sump drain....radiator appears to be slowly draining.
Going to rent a cooling system pressurizing pump to see if I can see where it is leaking. It doesn't appear to be at the water pump but I can't see down in the timing chest very well.
Dick

[miked]

People have a habit of sticking a chisel or screwdriver between the two halves of the water pump to separate the case. My friend and I had the same problem. With the sytem under pressure for a long time there was little discernable drop on the gauge. Only found by looking down the timing chain area and seeing some blue coolant doing a tiny spurt. Upon disassembleing we found an old wound. Had to surface grind and make back up with gaskets. Worked fine. I fit gaskets anyway to that area.
Believe the famouse BB does it.