What is my next step???

[Capt Mark]

Guess what I found today?............

I discovered the head gasket was leaking, I warmed it up pop the valve cover to

re torque the head and it is maxed out, my guess it was over torque and the bolts are

maxed out as well…..

History, for those of you that do not know I bought this 70/240 after it was sitting for

some 6 -7 years and am bringing it back to life….the OD says 130K miles the previous

owner said the head was done 30k back.

What do you guys think should do, pull the motor or just redo the head again?

What would your next step be??

[Bambikiller240]

Not sure what you mean when you say " I warmed it up pop the valve cover to re torque the head and it is maxed out". "What" is maxed out?

What, Where, and How is the head gasket leaking? (What fluid? Leaking Where? How bad?)

[Capt Mark]

Hi Carl,

It is leaking a little oil down on the block just above the dip stick, I went to re torque the head to specs and the bolts did not budge, I tried to back them off a 1/4 turn and the bolts would not budge. So I closed her up to consult the experts……

What do you think? need more info?

Thanks Mark

[Bambikiller240]

Well, how bad is the oil leak down the side of the block?

I drove a 240Z with what I call a minor seep at that area for 2 or 3 years without any problems. (I just wiped the area clean periodically and kept an eye on it)

I could have driven it further, but due to an accident and the need to switch all my "goodies" to another chassis, I had the time to rebuild the head and replace the head gasket.

How hard did you try to loosen the head bolts? They are torqued to 60 lbs/ft and have been subjected to countless heat/cooling cycles. Sometimes it takes some strong effort to start them to loosening.

PS, That area is where an oil passage goes up into the cylinder head to supply oil to the top-end of the engine.

[Capt Mark]

Roger that....I set my torque wrench to 55lbs/ft, I did not want to push it due to history of the car. I suspect it has been leaking for a while do to the build up and if the head was done 30K back they probably did not use new bolts over torque them exceeding the yield strength and did not re-torque them as required. BUT who knows….I think I will just drive it and see what happens… BTW under the valve cover was not too bad, some typical build up but no real sludge issues.

Thanks Capt Mark

[Bambikiller240]

Yeah, Lot's of guys don't replace the head bolts, but I would strongly recommend that you do so, whenever you decide to pull the head next.

[beandip]

I agree with bambi about replacing the bolts when you pull the head . Have you done a compression check ? Have you noticed any oil in the coolent or water in the oil ? If all three are good I wouldent pull the head unless the oil leak is sugnificant.

[Ed]

When you do replace the head bolts I would recommend using an air impact wrench to loosten the bolts. If they are by chance rusted in place you might break one removing it.

[Capt Mark]

Carl......New head bolts are on the list......

Beandip......Oil is clean, I need to do a compression check ASAP

Ed......I am sure they are rusted in...thanks for the air impact tip

I think I will drive it till the rainy season (summer) I have most

of the suspension parts to do as well........

Thanks for the input.....

Mark

[Capt Mark]

I have continued to drive it and power has stayed about the same....

Got a compression tester today and did a compression test today and it is all over the place......

#1 = 153 psi

#2 = 155 psi

#3 = 150 psi

<------head leaking here

#4 = 151 psi

#5 = 162 psi

#6 = 160 psi

What should the approx range be, L24 w/ and E88? I could not find

any specs in the books or on the net......

Thanks again for your help.....

Capt Mark

[Bubbleguinea]

are you kidding?? those are *good* numbers for an engine with a LOT of miles one them...are you getting oil consumption?

did you do the compression test correctly on a hot engine with no sparkplugs and throttle wide open?

those numbers are only +/-10 PSI which isnt bad at all.

stock is about 170psi. ive got 185 cause i've bored the engine out and shaved the head and decked the block....

[Bambikiller240]

The L24's (in good "no complaints" condition) that I've checked typically have about 155-165 or better, even with 125,000+ miles on them.

Nissan Factory Spec (Page ET-4 of my Nissan L20A/L24 Engine Manual) is 171 to 185 lb/sq in @ 300-400 RPM

** if you have the later version of E88 head, factory spec might be a bit lower.

EDIT: Nope, even the 73 FSM still quotes 171 to 185 lbs/sq. in. and 73 HLS30-U's came withthe smogged "late" E88 head.