The fun just won't stop [engine rebuild questions]

[PatGalvin]

Hello all

So, I finally pulled my engine to fix the rear seal leak. I had installed the Land Rover lip seal conversion kit that requires machining of the crankshaft.
Separated the tranny from the engine and pulled the flywheel. Seal looked pretty good but there was oil around the area where the felt seal was installed and oil around the area where the oil pan meets the sealing block, below the seal. It was leaking but I'm not certain if the leak is from the felt seal or oil pan.
Well, I have a new lip seal from RevingtonTR, so I might as well install it. And seal up everythinig even better than last time.

I flipped over the engine on the stand and pulled the pan. Now, I had run this engine for about 30 minutes to set the initial tune, when I put it on the chassis about 18 months ago. I found an oil emulsion in the bottom of the pan, indicative of water contamination in the oil. See photo.

So, you can all imagine my disappointment. I need to address the rear seal area oil leak, but more importantly, I need to address the water in the oil.
I had the block and head magnafluxed and crack checked at the machine shop, so I don't think that is the problem. Head was skimmed to ensure it is flat. Can you guys give me some ideas on the approach I should take to diagnose and fix my "water in oil" problem? I'm thinking head gasket or seal under liners, but wanted to check with you all. My compression was great and engine ran like a champ, for the 30 minutes of testing that I did.

Thanks for the tips. Much needed and appreciated.

Pat

 

[DNK]

See Head gasket thread
Is my guess
Liners moved?

 

[PatGalvin]

Liners should not have moved. Engine just freshly rebuilt for the first time so head hasn't been off since rebuild.

 

[DNK]

Before that,were the liners replaced or the deck planed? , see Randall's remarks about raised liners

All conjecture as I haven't a clue on those 4 bangers

 

[TR3driver]

I couldn't guess where it is leaking, but I would sure want to pull the liners out anyway for careful inspection of the sealing surfaces and new Fig 8 gaskets. Double-check the condition of the head as well; and liner protrusion after you get them back in. My liner problems have all been with them being too short, but too tall could cause oil/water leakage.

Another possible problem spot is the core plug in the top of the cylinder head. They tend to corrode from the inside out, or the replacement may not have sealed properly. The plug is aluminum, so magnaflux won't show any problems with it. The racers generally remove the original plug, tap the hole and use a pipe plug. Done properly, the pipe plug sticks up (don't want it too deep), but gets hidden by the rocker cover.

On the felt around the rear main bearing, I've heard that some gasket sets don't come with enough felt. You need to cut the felt into short lengths (3/4" or so), soak it in your favorite sealer (I use Permatex Aviation for this), and then tamp it firmly (like with a drift & hammer) into each hole until it won't take any more. I like to see Permatex oozing out of the seam. Then cut the felt so it is still sticking out of the hole a bit, so the pan gasket mashes the last little bit back into the hole.

 

[PatGalvin]

Hi Randall

Thanks for the responses.

Question on measuring cylinder sleeve protrusion. Say you have a clean block, just back from the machine shop, and new sleeves. You would use gasket seal under and over figure 8 gaskets and place sleeves in the block. Seat them with a mallet. Do you then measure, or do you apply downward pressure on the sleeves before you measure the clearance? The Bentley manual calls for 0.003 to 0.0055 proud of the block measured with a straight edge across sleeve top and a feeler gauge between straight edge and deck.

As far as the core plug in the head, can you inspect it by just viewing the top of the head? Or how do you inspect this?

My experience with the original build is that the Payden gasket set does not provide enough felt and so I bought more from Moss. I installed with a homemade drift. I will be taking a lot of care when installing this next time.

 

[TR4nut]

Pat-

Not sure it helped, but I used an old head gasket and torqued down the head once to seat the liners then I checked liner clearances - I did see a difference doing that from the initial readings.

The aluminum plug in the head can leak and it may not be obvious. But I do know of two cases where that happened and you could see a few drops of fresh coolant on top by the plug which is how it was diagnosed. At this point I'd probably reseat the liners and just get the plug replaced for good measure as it won't be a very costly operation other than your efforts to pull things apart.

 

[PatGalvin]

Thanks Randy. I will get aluminum plug replaced. I'm going to take the head in and get it checked, just to be sure it is tight. They can do the plug then. The aluminum plate on the front of the engine, to which the sump bolts, is stripped and needs a helicoil anyway. They can do that at the same time.

Pat


Pat

 

[DanB]

If you have not pulled the head yet you could do a leak-down test.

 

[PatGalvin]

Leak down test is for testing rings and valves, right? Is this also for water leaks into oil system? I do have head on but have emptied coolant and oil and dropped pan.

 

[TR3TR6]

Pat, just for your information. I started getting water down around my rear seal and discovered it was coming from the plug on the back of the block on my TR3A. It was a little harder to replace with the engine still in the car. It was just like Randall said, it had corroded from the inside around the edges.

 

[TR4nut]

Leak down test is for testing rings and valves, right? Is this also for water leaks into oil system? I do have head on but have emptied coolant and oil and dropped pan.

That's not a bad idea from Dan if you could rig up a way to pressurize the water jacket to say 10 psi - it might let you confirm at least if you see anything going on in the liner area.

 

[PatGalvin]

Thanks Randy (and Dan).
While I've got it on the stand, I'm going to look for a way to fill the cooling system with water and pressurize to 10 PSI. That shouldn't be too difficult with $20 and a trip to Ace Hdwe. At least if it's a liner problem, I should see the water leaking down beneath the liners, as I peer up under the engine. I'll report back how this works.

If I pressurize the coolant system and it's a head gasket problem, where do you think the water will emerge? Any thoughts on where I should be looking?

Pat

 

[DanB]

Thanks Randy (and Dan).
While I've got it on the stand, I'm going to look for a way to fill the cooling system with water and pressurize to 10 PSI. That shouldn't be too difficult with $20 and a trip to Ace Hdwe. At least if it's a liner problem, I should see the water leaking down beneath the liners, as I peer up under the engine. I'll report back how this works.

If I pressurize the coolant system and it's a head gasket problem, where do you think the water will emerge? Any thoughts on where I should be looking?

Pat

I would think that if you are pressurizing the cooling system that you should remove the spark plugs. If the head gasket is leaking into the cylinders water would come out there.

 

[PatGalvin]

Hi Dan
I have water in my oil. No indication of combustion gasses in the coolant system. I'm a rookie at this, but I figured I had a head gasket problem, where pressurized coolant was leaking across into an oil gallery and making it's way down to the sump. Or, a leaky sleeve, which I'll also check by pressuring the system. Any thoughts on this?

 

[Darrell_Walker]

Hi Pat,

I supposed anything is possible, but since the cooling system only should be running around 7 PSI, and the oil system well above that, any leak between the oil and coolant system should probably result in oil in the coolant, rather than coolant in the oil (at least for the passages that go through the head, which are all pressurized, there are of course places like the sump and valve cover that don't have pressurized oil).

-Darrell

 

[PatGalvin]

Hi Darrell

I just figured that there were low pressure oil drain holes that flow through the head and drip down to the sump. How does the quart of oil I add to the rocker cover make its way down to the sump? On solid block cars, it is not uncommon to overheat, warp the head, and have water in the oil. On my MG Midget (back in 78), I had this experience. Fix was to remove the head, surface it, and install new gasket. How did coolant make it into the sump if not from a water passage to an oil passage in the head? Thanks for your thoughts on this. I'm still learning.

Pat

 

[Tim Tucker]

How did coolant make it into the sump...

Past those figure 8s. The idea of pressurizing the coolant system was an excellent idea. How did that go? Having just put my engine back on the road I can feel your pain. Were your fig8s steel or copper? I used KW Copper Coat on my head gasket and fig8s. Here is a rather interesting website discussing cooper head gaskets, sealant, letting them settle overnight under pressure, etc. I followed his "slow" approach: letting the gasket stand overnight before final torgue. I was a bit surprised by the movement I got to return to the original torque I had put on the fig8s and then the head gasket. Best of luck to you. Tim

https://www.aera.org/engine-professional/copper-head-gaskets/

 

[Darrell_Walker]

I just figured that there were low pressure oil drain holes that flow through the head and drip down to the sump. How does the quart of oil I add to the rocker cover make its way down to the sump? On solid block cars, it is not uncommon to overheat, warp the head, and have water in the oil. On my MG Midget (back in 78), I had this experience. Fix was to remove the head, surface it, and install new gasket. How did coolant make it into the sump if not from a water passage to an oil passage in the head? Thanks for your thoughts on this. I'm still learning.

Yes, there are quite large holes where the pushrods come up, that is where the oil drains back down. So if you have water leaking into the valve cover area, it would run down there, or if you had a really bad head gasket seal, it could run down there. That would be pretty bad, as coolant won't be a very good lubricant for your cam and lifters. But to have such a bad seal on the head that coolant make it way over, I would think you would have major leaks from the combustion chambers, too.

 

[TR3driver]

Leak down test is for testing rings and valves, right? Is this also for water leaks into oil system? I do have head on but have emptied coolant and oil and dropped pan.

Right. However you could pressurize the cooling system with air and see if you can find a leak that way. I use a tee with a Schrader valve & pressure gauge that I can screw into the heater fitting on the head, but there are lots of other ways.