What do you recommend?

[rcb280z]

So after several months of running the alumaseal through the cooling system of my 77 280 I still have a coolant leak between the block and head. I have contemplated re torquing the head bolts but am a little nervous. The last time I had the head off was in 1997 or there abouts. So its been awhile. Has anyone attempted this and what were the results? I was thinking of just breaking them loose (just barely) and then re torquing, in proper sequence of course. Im nervous because I believe I could take a chance of cracking the head if my leak is caused from a warped head. Ideas, experiences, and suggestions are appreciated.

[LeonV]

Replace the head gasket. It's a relatively easy job on the L-series.

[Zed Head]

That's a bummer. I can't remember if you said the engine had ever overheated but you might consider having another head ready to swap on. Depending on how many miles are on the current head and the odds of warpage. My leaking head didn't show any signs of combustion chamber leakage but is about .007" bent. Bowed up in the middle, but it leaked on the end.

Retorquing won't crack the head, they're actually pretty flexible. The odds are probably against it fixing the leak though. I would just check the torque on each bolt to see if you had some loose ones that might explain the leak. Start with a low number and work up to spec. Good to know anyway, for future work. Maybe you had an older style gasket that was supposed to be retorqued after a few miles and wasn't, allowing a leak to develop.

[rcb280z]

Leon, I am tossing that around as well. If I have to remove the head I should go on and do an "overhaul" of the complete engine. I want to do a compression test as well to determine whether or not to overhaul it.

Zed, no on the overheating. The current head has 197,000 miles but had a valve job 97,000 miles ago. I do recall retorquing the head after so many miles when I had the head rebuilt. It was resurfaced but the block was not because the machine shop said it was "good", IIRC.

[Zed Head]

Just curious, but do you remember the brand of head gasket?

[rcb280z]

Im thinking it was a felpro back then but not 100% sure. That brings me to another question, what would be the best gasket if I were only to replace the head gasket? Haven't decided which way to go yet. Just head gasket or whole overhaul. After 97,000 miles Im thinking overhaul. But I need to do compression test first before I decide.

[LeonV]

A compression test is a good idea and if it shows any signs that something is wrong, make sure you check leak-down as well. If all is healthy, I'd take the head to the machine shop to get checked. An alternative is buying a used head as mentioned above, sending that head to the machine shop, and then just swapping heads.

[rcb280z]

Good idea as well Leon. Going to run compression test this week sometime and post results.

[rcb280z]

All plugs out (plugs look really good), throttle open all the way, remote starter in hand, compression gauge hooked up and the results are from 1-6:

150-170-155-152-172-170. Took another reading of the lower ones with identical results. I squirted a small amount of oil into the 3 lower cylinders, waited about 5 minutes and tested the 3 again. Here are those results:

(1)152 (3)158 (4)152. Didn't raise the numbers enough to be considered a ring issue. The funny thing is, the engine burns 1/2 a qt of oil every 3 months which about 2300 miles. Now I'm thinking maybe I didn't squirt enough oil into those cylinders when I retested.

Next I checked valves for those 3 cylinders and discovered they were off from .001-.002. After adjusting the valves I ran a compression test again and got the same numbers as the first test. If #1 cyl had around 170 then I could suspect the head gasket between 3-4 was "going" but, that wasn't the case. I must have more than 1 thing going on here. Coolant leak, maybe some valve issues. Anyway, I'm still not sure what I'm going to do or should do next.

[rcb280z]

ZedHead, I remembered something....I did use the felpro gasket. Now I see they are "perma-torque". I don't remember that when I replaced the HG 97,000 miles ago.

[LeonV]

You can do a leak down test but those compression numbers aren't awful. I bet some valves are just not sealing as well as the others. If your oil consumption isn't the rings, it could be the valve stem seals, an item that gets replaced during a head job.

[rcb280z]

Yeah Leon I agree the numbers aren't awful. Because I couldn't manipulate the numbers on those cylinders with some oil I'm assuming the valves are not sealing as good as they should be. So I will start looking for an engine overhaul kit because like I said before if I take the head off I may as well do a complete overhaul. My timing chain is on "number 2" mark so it has stretched. There are a couple of things leading me in the direction of overhauling the engine. The good thing about is I don't have to do it right away. That gives me some time to search for a good machinist and recommended engine overhaul kit. So with that said any suggestions on an engine overhaul kit? Anyone?

Thanks.