Should I oil / grease the wishbone bolts

[HoraceM22]

Morning again
When re-assembling, Should I oil / grease the wishbone bolts. They were dry when taken apart.

[Dilkris]

Just out of interest - are you repairing or rebuilding? What model is it? S1/S2/TC/TCS?

[EuropaTC]

Hi there,
Personally I do apply a smear of grease to the non-threaded section of all bolts that can see rain/salt/etc because I think it helps when you come to pull it apart again.  Whether you should of course is open to debate and you'll probably find as many for as against.

Just bear in mind that oil or grease on the threaded sections will affect the actual torque values on the bolts because friction is reduced and  thus more of your tightening effort goes into the bolt tension rather than overcoming friction to move the nut/bolt.  AFAIK the numbers given in manuals are meant for dry threads because oil/grease/WD40/etc will have differing effects on tightening and the only constant you can rely on is a clean, dry thread.

Brian

[Clifton]

According to this test. Anti seize doesn't change values on threads.

https://www.youtube.com/watch?v=V1Y3aB94lwU

[4129R]

I coat those bolts or any bolts likely to be removed or have motion with Copperslip which prevents corrosion.

[EuropaTC]

According to this test. Anti seize doesn't change values on threads.

https://www.youtube.com/watch?v=V1Y3aB94lwU

Hmm, I didn't get that message.

Admittedly I've only watched it once and could easily have overlooked/missed something but at 24:00 they said that "bolts that are supposed to be lubed, lube them. Bolts specified as dry, keep them dry".

The individual results they got did seem to vary with lubricants and even how much they put on the threads seemed to make a difference. If you are going for 100% repeatability then for me the only consistent situation is clean dry threads because from that video there was a minor difference even between compounds used. 

But to be perfectly honest I'm not convinced it's that critical on our cars, I would hope there's plenty of safety margin in the design to handle the 20-30% changes you may (or may not) achieve.

[Clifton]

22:50

[HoraceM22]

Thanks for all those thoughts.  I was thinking of a smear of copper slip, can't do any harm.

My car failed the MOT (first since 2016 !) on a broken front AVO damper spring and a seized rear brake slave cylinder. Removing the damper concerned me a bit but unnecessarily so, for after removing the shiny bottom bolt, and with just a series of taps, the top shiny stud just slid back into the footwell to halfway, allowing the damper to drop down. I bet it's not so easy on a real 50 year old car.
I was having problems sourcing a suitable spring compressor, but after a while , it dawned on me that I could just cut through the middle coil which gave me the required clearance, such that I could dismantle the unit to get the Part No.( A7.5 -250 )
7.5" long and 250 lbs. Spring rate - 2" bore, although Faulkner said they are 1.9"

It now transpires that AVO are now owned by Turbo Technics in Northampton, quite near to me, but all of these springs (and quite a few others I suspect ) are made by D. Faulkner Springs, but are special order only via TT then Europa Engineering, who had a batch of 20 on order but couldn't let me have a pair, as they were going out as spring/damper units. I tried sweet-talking Richard at Europa and he said he would try and sort a pair out for me.

My car is a '74 TCS. Totally rebuilt (Receipt from last but one owner for £45k!!!! Yes really, £28k labour, £45k total. More than the car was worth, obviously. AND the previous owner to him had had the body off, painted, retrimmed, rewired, new brightwork, screen, rubbers and loads of additional stuff.

I'll work out how much has been spent in this car so far (bills going back to when it was born) but I bet it's getting close to £75k in running costs and general upkeep, Unbelievable.

[BDA]

I’m not sure exactly what you’re asking. If you’re talking about the nuts on pivot pins of the front suspension, I think it’s not a bad idea to put a little anti seize or light lube to ensure that it will be easier to take apart later. Some anti seize on the pins under the bushings might be useful for the same reason. I think it’s a personal preference. I’m not in the habit of doing that and I never have any trouble taking something apart that I put together. My car lives in a garage too. If I parked it outside, that would be different but a Lotus should never be kept outside IMHO.

If you’re concerned about the movement of the wishbones on the pivot pins, there isn’t any. The inner sleeves of the bushings are clamped by the nuts against the frame and so they don’t move. So now might be a good time to remind you that the pivot pin nuts must be tightened with the suspension at ride height or you will likely tear the rubber in your bushings.

[dakazman]

I’m not sure exactly what you’re asking. If you’re talking about the nuts on pivot pins of the front suspension, I think it’s not a bad idea to put a little anti seize or light lube to ensure that it will be easier to take apart later. Some anti seize on the pins under the bushings might be useful for the same reason. I think it’s a personal preference. I’m not in the habit of doing that and I never have any trouble taking something apart that I put together. My car lives in a garage too. If I parked it outside, that would be different but a Lotus should never be kept outside IMHO.

If you’re concerned about the movement of the wishbones on the pivot pins, there isn’t any. The inner sleeves of the bushings are clamped by the nuts against the frame and so they don’t move. So now might be a good time to remind you that the pivot pin nuts must be tightened with the suspension at ride height or you will likely tear the rubber in your bushings.

                   

   Perfectly said. Make life easier for the next guy. Putting anti seize on the shaft always helps.
Dakazman

[EuropaTC]

22:50

Yeah, I got that, they used a lubricant on a bolt and the numbers matched on the rig and wrench.

The next test was using only a small amount of lubricant and the numbers didn't match. 99lbs on the wrench but 130lbs on the bolt rig. I would have thought that if adding thread lubricant made no difference to the bolt stress then it should have been the same, but it wasn't ?

I'm quite happy to admit I have no idea what's going on there other than there seems to be a distinct difference in bolt stress levels between a thread that is fully lubed and one that's partially lubed. It's sort of logical to me and the basis for my original comment on greasing the bolts vs torque settings in the manual, but if it's wrong, it's wrong ?

[BDA]

That video about torque wrenches was very interesting. Thanks for posting it Clifton!

 The "stiction" part is really about the difference between the coefficient of static and dynamic friction. Static friction is higher than dynamic friction and that's why when you get close to your torque and need to turn the nut or bolt just a little more, when you try to turn it that little more it will appear that you really have reached your torque - just as they demonstrated on the video. What I didn't notice them saying is is that when "retorquing" a bolt - as in to retorque your head nuts or bolts as it is commonly recommended - it is necessary to loosen each head nut before retorquing it. Just putting the torque wrench on the nut and pulling it will get you nothing. I was taught that by a friend who was an early mentor of mine and I surprised myself by teaching it to an engine builder I used when I was racing many years ago.

But I think I missed something when they used the anti-sieze on the bolt (at the 22:50 mark). They slathered it on the bolt and the torque was as indicated (101 ft-lbs gave 101 ft-lbs of "tight" as Clifton pointed out but when they just put a little and wiped away some extra, the result was, "the result is still an increase but less of one to be sure. 130 ft-lbs of tight from 99 ft-lbs in..." That seems to be the oposite of what they said since there was no increase the first time. Did I miss something??? Or am I out to lunch again?

[berni29]

Hi

All I can say is that I use copperslip on such bolts.

Berni

[HoraceM22]

What I was actually asking was only referring to the shaft of the bolt, not the thread.

[BDA]

Then my reply #8 above is what you need to know.