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TR2/3/3A Bad news...blown head gasket???

karls59tr

Obi Wan
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A few days ago I drained out some of the summer coolant from the TR3 and added antifreeze because the winters here are quite brutal and I do not have a heated garage. Went for a few drives and checked the antifreeze level and it was way down. I checked the oil level and it was way up!!! I've seen this before on older vehicles I've owned and I suspect I've got a blown gasket. Usually you can tell if there is antifreeze in the oil because you get a "chocolate milk" looking mixture in the oil. Hard to tell if this is the case because I run 20W50 in the oil and when STP is added it tends to make the oil look blacker than it should be. I guess the cylinder head will have to come off but are there any tests or advice before I do that?:(
 
Compression check. I was recently told about an additive you can put on the coolant which radically changes color in the presence of dissolved CO. But your description is a blown head gasket.
Bob
 
Forgot about an old shade tree test. Take off the rad cap, fill full, and run the engine. Bubbles indicate induced air. This test was usually done with the rear axle on jackstands and the car in high gear. Probably nobody would recommend the in gear part of this anymore.
Bob
 
When the head gasket blows you will usually have a pressurized cooling system and it would have to be really bad for that much coolant to get into the oil. I would first take the rocker cover off and look for any coolant leaking from up there. If it's a blown head gasket it would be running like a pig to get that much water in the sump.

Graham
 
I agree. Take off the valve cover and make sure that plug in the top of the head has not rusted through and allowed the water to come out. That happened on mine. I still had to take the head off and had that hole tapped for pipe thread and put a pipe plug in the hole.
Bob
 
The water will sit under the oil, so just crack the oil drain plug and see what comes out. If water, then the pan has water in it.. That does not mean for sure that the gasket is blown just that the water is mixing

steve
 
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Also the figure "8" seals, if made of aluminum , car corrode (dont use them) . But I too suspect the head plug
It is a threaded plug and is seldom attended to when the head is re-conditioned( seen it before ).
Hope this is your case much easier than the head gasket
Mad dog
 
I installed a pipe plug on the cylinder head many years ago. I checked it and it's still intact. The radiator was empty. I drained the black oil from the block and got 8 liters of oil and antifreeze and here is evidence of coolant and oil leakage on the block below the head so I definitely have a blown head gasket unfortunately. I may not be able to pull the head until Spring. I'm wondering if I should install cheap oil and filter and run the engine briefly and drain it to get the rest of the oil/antifreeze mixture out or just do that once the new head is on? My concern is that even though I drained the engine there would be residual amounts of the crap mixture sitting in the engine interior for 6 months? Any thoughts?
 
This will test if the head gasket has gone between coolant passage and combustion area.

But you can still have a breach between coolant and oil ways that this won’t show.
 
If you just caught it, you hopefully have not damaged the rod and main bearings. But, if you cannot open it now, I would empty all the coolant, drain the block and change the oil filter. Then add a few quarts of oil and run the starter, or start the engine for a minute to clear all the coolant out of the oil passages and bearings. If coolant is left in the galleries over the winter, you will ruin the bearings and possibly corrode the crankshaft and other parts.
 
If you just caught it, you hopefully have not damaged the rod and main bearings. But, if you cannot open it now, I would empty all the coolant, drain the block and change the oil filter. Then add a few quarts of oil and run the starter, or start the engine for a minute to clear all the coolant out of the oil passages and bearings. If coolant is left in the galleries over the winter, you will ruin the bearings and possibly corrode the crankshaft and other parts.
Well I drained the coolant and installed fresh oil and a filter which I will change again in Spring. Ran the car for a couple of minutes to wash the antifreeze out of the internals.I'm thinking I should probably flush the cooling system as well in Spring after I install the new head gasket. I may have driven the car for half an hour with the blown head gasket which has me concerned. I was planning on replacing the leaky oil pan gasket so I may as well have a look at the bearings while I have the pan off. I may do this now as the weather is not too cold yet. I've never had to pull a rod bearing before so this is new to me. Any advice on this and will I be able to check a crank bearing while there as well?
 
You can pull a rod cap and main cap to look at bearings. The only main cap you can get to is the center, which has the thrust washers. If a thrust washer falls out, you might have a time getting it back in (or maybe not; I don't recall how they fit and are held in. I would not remove bearing caps at this stage in any case, even if the thrust washers are not a concern. Clear the block as John says. When you get the head back on, run it and see if you get rod or main noises before you dig into the engine. You'll probably find its ok.
Bob
 
If you are like me, you will probably dive in too see what you can see.

steve
I'd like to dive in but it's getting colder here in Winterpeg and I think I have Reynaud's syndrome (not Renault syndrome) in my fingers from working on cars in cold weather.🄶 Karl šŸ˜€
 
Just a thought ,get a fresh head ready to go and just do a swap out when spring hits.
This makes it a day job rather than the machine shop shuffle.
Mad dog
 
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