Head gasket seeping - advice sought

[7T1240]

Hello all.

I'm seeing a small amount of coolant seeping at the center of the block / head mating point on the oil filter side. The amount is minimal, but it is there. Please advise me - should I go through the torquing sequence for the head and see if this eliminates the seeping? Or do I need to remove the head and install a new head gasket? Any other suggestions on how to address this?

Thanks,

Gary S.

[bobc]

Gary,

I see no harm in trying to torque the head bolts first. I doubt this will fix the problem though. If you're only talking an occasional drop or two, not seeing anything in the oil, then you might want to just keep it under observation a while. If it's your daily driver then I'd change the head gasket.

Best,

Bob

[jwtaylor]

When I first bought my 240 I had this same problem. A re-torque of the head did not stop it. I kept a close eye on it and after a couple of years the gasket blew. The head was warped, most likely overheated by the PO at some point. I had another head ready to go so down time not to long.

[7T1240]

Gary,

I see no harm in trying to torque the head bolts first. I doubt this will fix the problem though. If you're only talking an occasional drop or two, not seeing anything in the oil, then you might want to just keep it under observation a while. If it's your daily driver then I'd change the head gasket.

Best,

Bob

Bob and John,

thanks for your replies. The Z is not a daily driver. Since purchasing it 4 years ago, I do drive it on a regular basis, including about once a month in the winter. It's time for an oil change, so I'll do that to see if coolant is present (I haven't seen any in previous changes). As far as how much is leaking, I don't even really see a drop or two.

The evidence is some paint peeling off the engine block below and a little weep line right at the gasket. Maybe the heat from the engine is drying / evaporating the coolant?

Gary S.

[esprist]

Bob and John,

thanks for your replies. The Z is not a daily driver. Since purchasing it 4 years ago, I do drive it on a regular basis, including about once a month in the winter. It's time for an oil change, so I'll do that to see if coolant is present (I haven't seen any in previous changes). As far as how much is leaking, I don't even really see a drop or two.

The evidence is some paint peeling off the engine block below and a little weep line right at the gasket. Maybe the heat from the engine is drying / evaporating the coolant?

Gary S.

If you see head gasket leak wether it is oil or water, first thing you need to do is that you need to take off the head, measure the worpage of the head and block. Normally more-torque to the bolts are not recommended. Sometimes, it gets worse by doing so. Most old Z cars (streight 6 is a long engine) have this problem regardess of mileage on the car. If you are not driving it everyday, please keep your eyes on oil and coolant condition and level. If it starts to leak into the combustion, you will see a steam coming out from dip stick hole and PCV passage(or creamy water at oil filler cap). If you see consistant loss of water, then you might consider removing the head off for farther diagnosis.(Machine shop will tell you all)

Good luck!

Esprist

[bobc]

Gary,

If it's only that amount, then I'd just say keep an eye on it and enjoy driving your car. Be prepared to replace it in the future, by buying the materials now and start asking around for a good machine shop. It may blow out in the future or it may not. Since it's an occasional driver, you have the luxury of replacing the gasket whenever the problem gets worse.

That's just my two cents!

Best,

Bob

[WingZr0]

Crap, got the same problem now with my daily driver 280z and the rebuilt engine only has 700 miles on it. New head too. Started seeping under number 3 and 4 spark plugs then out to the others. No oil in water or oil burning so put in some Silver Seal in the colant couple days ago. Waiting to see if it holds up. Getting the head retorqued this weekend during the value adjustment.

Edited October 13, 2009 by WingZr0

[70 Cam Guy]

Crap, got the same problem now with my daily driver 280z and the rebuilt engine only has 700 miles on it. New head too. Started seeping under number 3 and 4 spark plugs then out to the others. No oil in water or oil burning so put in some Silver Seal in the colant couple days ago. Waiting to see if it holds up. Getting the head retorqued this weekend during the value adjustment.

In your case I would hope the shop would warranty their work if they built the engine (if it's needed)

[Ronaldo1973]

for me to avoid this issue in my next engine rebuild , "Is it recommended to use RTV sealants between the head gasket and the block?"

[esprist]

for me to avoid this issue in my next engine rebuild , "Is it recommended to use RTV sealants between the head gasket and the block?"

The answer is "NO" You shouldn't need it. I would used capper spray on Genuine Nissan headgasket(very well made) and used RTV sealant only where head, block and front cover meet.

Esprist

jdm-car-parts.com

[7T1240]

If you see head gasket leak wether it is oil or water, first thing you need to do is that you need to take off the head, measure the worpage of the head and block. Normally more-torque to the bolts are not recommended. Sometimes, it gets worse by doing so. Most old Z cars (streight 6 is a long engine) have this problem regardess of mileage on the car.

Esprist

Ataka, hello. When you say most old z cars have this problem, is it simply from usage and heat cycling, or is it indicative of the car having been overheated?

Crap, got the same problem now with my daily driver 280z and the rebuilt engine only has 700 miles on it. New head too. Started seeping under number 3 and 4 spark plugs then out to the others. No oil in water or oil burning so put in some Silver Seal in the colant couple days ago. Waiting to see if it holds up. Getting the head retorqued this weekend during the value adjustment.

Silver Seal - did this help?

Gary S.

[esprist]

Ataka, hello. When you say most old z cars have this problem, is it simply from usage and heat cycling, or is it indicative of the car having been overheated?

Silver Seal - did this help?

Gary S.

Over heated? It could certainly do bad on the head, but Not necessary........

Copper spray definitely helps to seal the gasket better, but streightless of block and head is a must especially if you are installing metal gasket with studs.

Esprist

jdm-car-parts.com