Cylinder bolt studs

[indyblue]

What is the difference between #'s 4,5,6 & 7?  #5 is sown as obsolete.  They all appear to be the same on my motor, which can be substituted for others?  I may need to replace some.

[racerrad8]

#4 - The outer four studs are longer.
#5 - same as #7 but they do not have the black rubber sleeve on them.
#6 - Has a shoulder at the base to position the gasket.
#7 - Same as #5 but they do have the rubber sleeve.


What size engine & year engine are you working on?

Why are you changing them?

Randy - RPM

[indyblue]

#4 - The outer four studs are longer.
#5 - same as #7 but they do not have the black rubber sleeve on them.
#6 - Has a shoulder at the base to position the gasket.
#7 - Same as #5 but they do have the rubber sleeve.

Thanks

What size engine & year engine are you working on?

Why are you changing them?

Randy - RPM

'84 FJ1100

I'm not planning on changing any if not necessary.  But I know when I do a project, stuff happens and I am just covering my butt if I ruin one somehow that I can replace them.  I am thinking of cleaning up the rust/crud from the exposed fronts that once had the rubber sleeves and putting heat-shrink tubing around them to replace the rubber.  The sleeves obviously were there to keep road grime from the front tire from corroding the exposed surfaces in the front of the cylinder/head.

BTW, how to remove them from the crankcase (do I even want to try)?  Double nut on top and back them out?  Wouldn't they be bonded with locktite and require a little heat?  The factory service manual does not mention any service procedures for them.

[racerrad8]

I think you will find the 1100 studs are all obsolete, I have not been able to purchase them for several years. The new studs are longer and require the new style nut as well.

You should clean & neutralize the rust from the old ones, paint them with some high heat paint on them and you will be fine. The corrosion is caused by the moisture & debris getting between the rubber and causing the corrosion.

They do have a thread lock on them, plus the years of heat cycling & debris corroding the threads, so removing them can be a probelm. Sometimes they break (andyb), sometimes they pull the threads, and other times you just cannot get them out without heating the case.

I would leave them be or you will have a bunch more work.

Randy - RPM

[indyblue]

Thanks for the info.  I will clean and paint them with POR 15, then use some shrink tube on them for extra protection and to emulate the original rubber sheathing.

[andyb]

They do have a thread lock on them, plus the years of heat cycling & debris corroding the threads, so removing them can be a probelm. Sometimes they break (andyb), sometimes they pull the threads, and other times you just cannot get them out without heating the case.

They can break, they can get absolutely welded in, they can also bend a bit.  Ask me what can go wrong with studs, I can send you a whole bag that looks like the who's who of problems with the damned things