R16 Long head bolt damage

[ScottieR]

I’m wondering if anyone knows exactly what might happen if the long head bolt on the R16 is used without the engine lifting bracket in place?

I’m a complete noob when it comes to head gaskets, I’ve done various engine, gearbox & diff swaps in the past, but I tend to try to keep them all as sealed units
But when my R16 ended up with milkshake looking oil I thought I’d bite the bullet and pop the head off to see what the issue might be.
Once I got in there I found that the gasket appears to be mostly ok, but I did also find that the previous owner has installed the long head bolt without also installing the engine lifting bracket.
Aside from the fact that I’ve got water in my oil, the head seemed to be seated fine and all head bolts felt like they’d been tightened to roughly the same amount when I removed them.
So what I’m wondering is, if that rear bolt has been torqued to spec but is ¼ inch longer than the other bolts, is it likely to have damaged the block where it’s bottomed out?
Does anyone have an experience with this?
Is there any way I can tell if damage has been done without removing and pulling down the engine?

Thanks,
Scott

[Habitat.pat]

Scottie, I’m sure others will post on this, but if you are interested in finding out if the bolt did bottom out, put the head on without a head gasket & run the bolts down until they bottom out. Do not torque. You can now measure the distance between the head & the bottom of the bolt head & compare it to the thickness of the used gasket. That will tell you if that bolt was applying enough clamping force.

When reassembling the engine run a bottom tap down the bolt holes to clean out the cruft so you can get an accurate torque.

Peace, Pat

[Bwk2000]

Hi Scott. The long head bolt must be used with either the bracket or washers. It’s unlikely that the PO damaged the block by not including this step but rather got a false reading from his torque gauge when tightening down the long bolt since it bottomed out before the proper clamping force between the head and block could be applied (I’m sure he thought it was).

If so, that’s the area where the mating between the head and block would be weakest and likely to blow out a piece of head gasket or maybe even just seep past. Examine that area of the head gasket closely - I’m betting that’s where the coolant leak originated. Hopefully an easy fix!

Let us know.

Kai

[Gregs672000]

I'm not very familiar with R16 heads, but if it's still off you could have it pressure tested for cracks and check for warp just to be sure. However, the bolt issue sounds likely if the bolt does indeed bottom out without the bracket.

[ScottieR]

Thanks for the info guys.

Pat, your suggestion of putting the head on without a gasket and bolting down until the bolts bottom out is a great idea. And I will definitely chase the threads before putting it all back together.

Kai, thanks for the reassurance that there probably wasn’t any damage done by the PO. To my, admittedly very untrained eye, there was no sign of any blowout or even any seepage on the back corner where the long head bolt goes. In fact there was very little sign of gasket damage at all which of course worries me a little because it might mean the head gasket wasn’t the actual problem. But for now I’m going to try to stick with your positive thoughts and hope that it is indeed an easy fix.

Greg, I agree that having it pressure tested and checked for flatness by a professional would be the ideal course of action, but I was hoping to just throw the head back on and not spend too much time/money on it. I’ll check the head and the block for flatness myself as best I can and if I find anything worse than 0.1mm (.0039") then I’ll have to reassess my plan and get a machine shop involved.

Here’s a related question, should all the head bolts have washers on them?
In the CarPartsManual.com manual there is a part 11058-18810 mentioned as “WASHER-CYLINDER BOLT T3,2” with 9 used, presumably the long bolt with the slinger bracket didn’t use one.
My engine is an earlyish, 3 main with iron head if that makes any difference, but there were no washers on any of the head bolts. Has PO failed to put them back on or were there never there on my engine?

Another somewhat interesting thing (to me anyway) was that all the head bolts came out fairly oily except the front right bolt which was completely dry and had a smidge of surface rust, nothing too bad – I just thought it was odd that 1 bolt was very different to the others. Does that seem normal?

Thanks again,
Scott

[david premo]

Just an FYI Scott, when working on R series Nissan engines it necessary to keep checking the torque on the head bolts. They take awhile to settle down, so keep checking the torque until it settles down.
Dave

[Bwk2000]

I think the early iron heads (with factory bolts) did not use washers and that the latter aluminum heads did use them (Note item #25 [the 9 washers] isn’t actually shown anywhere on that diagram).

Also, from what you describe, I wouldn’t be to concerned about the condition of the bolts. Now, if you had oil filling the bolt holes or maybe a heavily rusted bolt(s), that would be a different story.

[ScottieR]

Dave, Thanks for the tip on checking the head bolts. After the initial torquing I was planning on only coming back and re-torquing one time after a few runs/heat cycles, but it sounds like I better do it several more times than that… which might take a while, the rest of the car isn’t exactly “drivable” at the moment anyway.

Kai, thanks for once again giving a positive response rather than the doom and gloom that keeps going through my head. You are 100% correct that the washers aren’t pictured, I did wonder about that. So I guess my engine never had washers on the head bolts. I’ll hopefully be using some new Dorman head bolts, all the same length. So presumably I can use those without washers too, just a drop of oil under the bolt head. I say “hopefully” because last time I ordered a set of these bolts they never arrived.
The 9 bolts were pretty oily, but I don’t think I’d describe the bolt holes as “full of oil”, so hopefully that’s all ok. Once I get the chance to clean everything up and chase all the threads and blow out any dust, oil, debris etc. I’ll visually inspect as best I can, might even take a look using a crappy endoscope thing I’ve got, but I don’t really expect to see anything much by using it.

Another question, Do you guys usually put the head gasket in completely dry or do you use a copper spray or... something else?
I know in general across all engines there’s a fair but of debate with many people claiming the spray is not required for ‘modern gaskets’ but I was wondering if there was a consensus here for use with the R16?
I was planning on putting the gasket on dry because none of the manuals seem to mention using any extra sealant, but reading the instructions over on datsun.org is making me think maybe I should use a copper spray.

Thanks for all the help,
Scott

[Bwk2000]

Fads come and go. Good mechanical principles are forever. Clean, smooth & dry surfaces make for the best gasket mating conditions.

My $0.02 - Avoid any kind of sealant on the head gasket.

[Gregs672000]

Ya, no need for a sealer in my experience. I personally would feel better with proper hardness washers, especially on an aluminum head... you want the resistance to be on the threads, not from the bolt galling into the softer aluminum. Just my thoughts. All my experience is with U20s, but multiple re-torques after several heat cycles (more than one after the initial) have not been necessary (I'm using studs) but I'm no expert and defer to other's experiences and manufacturers recommendations. As said, clean mounting surfaces, clean and tapped holes, proper sequence and steps with a good torque wrench and you should be good to go. Check torque values for the bolts/studs dry, oiled and with assembly lube as they can vary a significant amount.

[ScottieR]

Sounds like the consensus is "No sealant on the head gasket" - I'm fine with that, that was my original plan and it saves me having to go out and find someone who has some in stock.

Greg, I agree with you about the washers on an alloy head, I think it's probably a bit less critical on my old iron head though... at least, that's the argument I'm running with

Thanks.

[DAC21]

Sounds like the consensus is "No sealant on the head gasket" - I'm fine with that, that was my original plan and it saves me having to go out and find someone who has some in stock.

Greg, I agree with you about the washers on an alloy head, I think it's probably a bit less critical on my old iron head though... at least, that's the argument I'm running with

Thanks.

I have no experience having replaced the head gasket, but a lot of reading on 311s over the last three years. I know many have recommended silicone JUST around the oil gallery hole of the gasket.

[Gregs672000]

"I have no experience having replaced the head gasket, but a lot of reading on 311s over the last three years. I know many have recommended silicone JUST around the oil gallery hole of the gasket."


There used to be an issue with U20 heads where they could leak at the back oil return, but nissan and aftermarket (?) fixed that with a built in sealer. I don't know if that was a problem with the R. Good catch though!