replace head bolts with studs without removing head

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I have a veeeery slight seep on the HG. Id like to either retorque the headbolts or just replace them with studs.

Dont want to remove the head, can i replace the studs one at a time and retorque initial then when they are all in do the second and third passes?
 
replace one at time, keep tension on head gasket. did that on an RB. never retorqued them. Follow stud manufacturers torque specs.
 
Naplm00 said:
I have a veeeery slight seep on the HG. Id like to either retorque the headbolts or just replace them with studs.

Dont want to remove the head, can i replace the studs one at a time and retorque initial then when they are all in do the second and third passes?
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Are you thinking that going from bolts to studs will fix a leaking head gasket?
Let me know how that works for you.
 
Naplm00 said:
head was never retorqued so im hoping the extra clamping pressure will help it from becoming a leak, yes
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Leaking coolant or oil and where is it leaking? And is this leak on a new build or an engine that has some use on it?
Head studs are not cheap. You will spend some money and time swapping those in, to find it did not help.
If the head bolts are tighten to the factory specifications the head gasket is already crushed and held in place by the bolts. More torque is not going to crush the head gasket more.
More torque (more clamp load) will help to stop the high cylinder pressure in a built racing engine from having the head gasket get pushed out and fail from moving around.
 
Naplm00 said:
Engine is a new build has about 1500 or 2,000 miles on it.

It's an oil seep under the intake side, very minor.

Studs are relatively inexpensive I think at around $150. Clamp pressure on the studs is 80 ft pounds. That's higher than stock
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Are you sure the oil leak is coming from the head gasket? There is one pressurized oil line through the head gasket. It feeds the rocker arm shaft and is located back by #6 cylinder towards the rear of the block. Even the oil drain backs are on the distributor side of the engine. There are no oil lines
on the intake side of the engine. The most likely leak source is the valve cover gasket. Or if you have an automatic transmission, the lines that run to the cooler are on the intake side of the engine. Maybe a pinhole leak in one of those lines.
I would do more looking.
 
Naplm00 said:
I'm surprised of this too.. valve cover gasket is new and torqued properly. I've had all sorts of issues with leaks on this motor since it was built I'm just trying to get them cleaned up.

Maybe it's due for another valve cover gasket. I wish there was something better than cork
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cork gaskets have worked on a lot of engines for many years.
When changing out the gasket try these tips:
1) With the valve cover off the engine, closely inspect the bolt holes. They need to be flat, after many dis assemblies and re uses the metal around the bolt holes can get bent in. If they are use a metal block and a light hammer to reshape the metal flat.
2) Try the valve cover on the cylinder head without a gasket. it should fit all the way on and not rock. Look to verify that there is not some excess stock or other item preventing the valve cover from setting all the way down.
3) Without the valve cover in place, run each valve cover bolt in to a mounting hole and run them all in to verify that there is not debris in a hole or a bad thread that is preventing a bolt from running into the proper depth.
4) Be sure the valve cover gasket contact surface and the rail of the cylinder head is absolutely clean and flat.
5) Put a light coat of Permatex Hi Tack on the valve cover gasket area and set the gasket into the valve cover. be sure it is fully seated and in position. That will keep the gasket in the valve cover when the valve cover is removed from the head.
6) Assemble the valve cover to the head, install the bolts, do a loose-hand tight to all. Generally I don't use a 'torque' spec on valve cover and oil pan gaskets. I found that will over press the gasket and cause it to squeeze out. I get all the bolts started, then working from the inside out tighten each a bit then go around repeating the sequence. A good hand tight is all it takes. Check the valve cover bolt tightness after a short drive and then after a hundred miles or so, if any loose bolts are found, tighten them a bit more.
7) Verify that you have a functioning PCV valve connected to manifold vacuum and a breather on the valve cover that lets filtered air in. If the crankcase is not ventilated properly pressure will build up and that will cause oil leaks.

good luck and post back on what you find.
 
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A higher tq value for the stud [ v bolt ] does not necessarily mean that the clamping force exerted by the fastener will be greater. Stud probably has fine threads for the nut, which requires more tq to overcome the friction of the additional area of thread engagement; actual clamping force on the head could be the same.
I would doubt that re-torqueing is going to fix a weeping issue because it will take substantially extra clamping force to stop the weeping. May work if the original fastener was under-torqued.
 
Unless you have the very hard to find original style THIN steel head gasket, there's ZERO need to retorque. Modern composition style head gaskets do not need retorquing. If the head gasket is the composition style and it is seeping, you have the beginning of a head gasket failure. Squeezing it down harder with retorquing or head studs ain't gonna do it.
 
I believe you can certainly successfully replace the bolts with studs one at the time. Whether it will fix your issue, will remain to be seen. I will recommend this though. If it was ME, I would drain the coolant first and then do the job.
 
Nap,
Have you looked at a ARP catalog or website? The tq value in the tightening process is based on the bolt material [ metallurgy ], the threads used & the friction value of the lubricant used on the threads. The final clamping force of the bolt or stud is based on the material, which should be the same whether stud or bolt; the tq # is merely what is reqd to achieve that.
Studs are often used on race engines that are stripped regularly because it saves time.
 
RRR, you are correct.

As ARP says, their recommended tq values represent 75% of the fasteners yield strength. If the bolts & studs are made of the same material, then the clamping force is the same for both.
 
Bewy said:
RRR, you are correct.

As ARP says, their recommended tq values represent 75% of the fasteners yield strength. If the bolts & studs are made of the same material, then the clamping force is the same for both.
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Close, but not exactly. The studs will more consistancy because of the thread quality & hardened washers. Even with lube, old threads, cleaned or not + the spot-face surface quality can cause a pretty large variation on the amount of stretch per rotational-drag torque on cap screws.
 
Naplm00 said:
this is site is so polarizing, what a circle jerk about an obvious answer. over it
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If it was so obvious then why the question? I was thinking it was a good discussion for your benefit. Nobody gets a paycheck for trying to HELP you. You might consider that before throwing our an almost insulting statement. I searched for about 15 minutes for the factual link I posted. I can just as easily ignore you next time.
 
how is it insulting? and yea it a circle jerk . just ignore me , this community is toxic
 
Naplm00 said:
how is it insulting? and yea it a circle jerk . just ignore me , this community is toxic
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Naplm00, your statements in your most recent posts do a lot to explain why your engine issues have not been resolved. Remember, you are the one with the motor issues, not me, not Rusty or the other folks that offered insight. Apparently even Doug D has walked away from you. Put me in that group also.
 
Naplm00 said:
this is site is so polarizing, what a circle jerk about an obvious answer. over it
Click to expand...
Look Dude, You can;

1) do what my68 suggested, and verify where the seepage is.
2) retorque the head bolts and verify they are/are not to spec(tip-You can tack on an extra 5ft-lbs no problem)
3)go ahead and swap studs in one at a time, I'd do it in torque sequence 10lbs shy of spec, then do them to spec in sequence 2x.
Not being there or having been involved with this, We can only provide information & suggestions, & many "simple" things in life don't have easy answers. I was looking for the sheet of paper I recorded the torque values on when I did a set of rod bolts to stretch. Snap-on 1% accurate dial wrench, I wanted to see the variation bolt to bolt in drag-torque to achieve the .0067" stretch value. I can tell You the lowest was in the high 50's, & the highest was in the low 80's, & that's for real.....didn't see that comin'.....but that's what it was...
 
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