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TR4/4A Blown Head Gasket?

KVH

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I'm not having much luck lately. Yesterday I took my older 4A for a drive. It overheated very strangely, right in the cool weather and after only 5 minutes of running. I checked the radiator. Coolant was low, and it's full of goopy, gritty muck at the filler neck. I pulled the dipstick. I'm "overfull" with the oil looking almost an orange opaque. What possibly has happened here, and could it relate to somewhat loud tappet noise I had been hearing over the past 8 months? Darn, I don't want to hear the diagnosis all that much. I've only got about 10K miles after a rebuild 10 years ago. Why would my head gasket fail? What a drag! OK, I'm listening . . . .
 
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A blown head gasket isn't the end of the world. Not terribly expensive or difficult to fix. If it were me, I'd do some compression tests to confirm it. Then, go from there. If the head gasket is blown, it would also be a good idea to check the head and block surfaces for flatness. I think there is also a spec for cylinder liner protrusion above the block surface, which also would be good to check. People who rebuild engines don't always get everything right.
 
I'm actually worried I didn't re-torque, but it's so long ago, I'm just not sure. I might have forgotten back then.

I'll check compression, but if it's good, what would I look for on the old gasket as evidence--and thereby hopefully rule out something worse, like the figure 8s or a crack somewhere?

Or, if I pull the head, should I just plan on replacing the rings and figure 8s anyway? How do I decide?

By the way, I've had tappet noise for a year, so I'm replacing the lifters and I might pull the cam. What I do recall, is that I didn't break in the new cam they way I should have with zinc, 2500 rpms and all that. I just didn't know back then.
 
Not going cost anything to check compression, then retorque head. If you get some excess movement, check compression again after retorque. See what that does. Doubt rings and figure 8 gaskets are bad.
Marv
 
All the head gasket failures I have dealt with have been cylinder/coolant failures - never had coolant into the oil but of course it can happen.

By all means, a compression check is easy to do -- but if the leak is just from a coolant passage to an oil galley then compression may be fine. Possibly a pressure test of the cooling system would be more revealing. The auto parts chains have a loaner tester for this:

https://www.oreillyauto.com/site/c/RentalTools.oap

If you retorque the head - I like to mark the nuts with a spot of paint so after re-torqueing I can see which ones moved and by how much.
 
I'll check the compression this evening. Last night I inspected both the coolant and the oil. The coolant looked fine actually. It was a slight green, the antifreeze color. However, on closer examination it was very slippery and oily and left a film over my fingers from rubbing at the bottom of the pan. The oil appeared opaque and brownish, though I could not detect any water in the oil. I was wondering whether the brownish color could be the ZDDP that I added or the full-court of Valvoline 50 weight racing oil with extra ZDDP. Certainly, the sludge in the radiator indicates something very wrong.
 
...The oil appeared opaque and brownish, though I could not detect any water in the oil...

You may be stressing over nothing. Your prior description "the oil looking almost an orange opaque" was more alarming -- I realize it can be hard to communicate color and texture with words.

Coolant in the oil usually appears as a milkshake color & texture. Chocolate milkshake that is as it is the only acceptable flavor of milk shake. If watching closely one may also detect a rise in 'oil' level in extreme cases.

The coolant should feel slippery and oily and leave a film. As for the sludge in the radiator in it -- this could be the normal crap that accumulates in an old engine or even the remnants of some old stop-leak product.

One course of action would be to flush the block well with your garden hose, change the oil and watch closely what happens next.
 
Having only recently suffered a bad head gasket, I can tell you that your symptoms are the same as what I had. The gasket had leaked letting water across into the cylinder. Solution-- remove the head and replace the gasket. While there look for any other problems such as the top surface of th eblock and the mating surface of the head being flat.
Also a good opportunity to look at the tappets and cam regarding that extra noise.
Charley
 
...The gasket had leaked letting water across into the cylinder...

This is the head gasket failure I have had on these engines - the gasket around the center coolant passage between 2 & 3 is especially vulnerable. But those failures all had the distinctive smell of coolant in the exhaust and no affect on the oil.
 
You may be stressing over nothing. Your prior description "the oil looking almost an orange opaque" was more alarming -- I realize it can be hard to communicate color and texture with words.

Yes, but I tend to think there must have been coolant there because the level on the dip stick was above the full mark, and the color was "sort of" a light brown (little bit orange), maybe like a light chocolate malt. But maybe more importantly, I never broke the cam in correctly back in 2005, and it's time to replace the lifters. Too much noise. I'd like to avoid pulling the camshaft, too, but is that a must? Let's say the lifters look a little worn but the cam lobes look smooth. Would it be wrong not to just replace the cam? My question stems from a long life of fixing and replacing anything near me that doesn't look perfect. It's a hard habit to live by.
 
You may be stressing over nothing. Your prior description "the oil looking almost an orange opaque" was more alarming -- I realize it can be hard to communicate color and texture with words.

Yes, but I tend to think there must have been coolant there because the level on the dip stick was above the full mark (though I concede just "dumping" a quart in for good measure a month ago). About that oil, the color was "sort of" a light brown (little bit orange), maybe like a light chocolate malt.

But maybe more importantly, I never broke the cam in correctly back in 2004-2005, and it's time to replace the lifters. Too much noise. I'd like to avoid pulling the camshaft, too, but is that a must? Let's say the lifters look a little worn but the cam lobes look smooth. Would it be wrong not to just replace the cam? My question stems from a long life of fixing and replacing anything near me that doesn't look perfect. It's a hard habit to live by.
 
My mechanic tells me that the cam and lifters get mated and should be replaced together if replacing the cam. But it seems like you should be able to replace the lifters if only doing those. My very limited experience has been that if the lifters are bad so is the cam. But pulling the head off will give you the opportunity to CAREFULLY remove the lifters and look them over as well as look down at the cam without pulling it out of the engine. Remember to keep the lifters identified by where they came from in case you will be able to reuse them.
Charley
 
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