WHITE 666 Cylinder head

[chrismanby]

Hi there.

My White 666 has blown a head gasget.
Normally to remove a cylinder head is no big deal... undo the nuts add a little heat and some light mechanicle encouragement ...
But not so this time. After using 3 crowbars, 6 steel wedges, 2 2½ ton jacks, oxy acetelyn torch and 2 cans of WD 40, the head is still stuck. Seems to be sticking to the head studs.

Have now decided to remove manifold etc. to gain acess for 2 more jacks.

Now for my question. The head studs have a thread size I cant seem to find in my chart of thread sizes. Does onyone here on these Holy pages know the correct size?
It seems that there are 16 per inch, which would make it a 3/4" UNF according to my chart. This does not however fit the diameter. Nothing in my chart, neither metric nor "inch" seems to corrospond to the nuts and bolts on the engine.
I would like to get some bolts so I screw them into the loosend nuts, so I can "motivate" the studs with a large hammer after lifting up the cylinder head on the 4 jacks from beneath.

Alternative solutions to solving the problem are welcome !!

Chris

 

[73m819]

what motor are you talking about, be real careful about jacking or FORCING a long single 6 head, you can crack it fairly easy, then your screwed

 

[NDT]

It is 11/16"-16 and there are 17 nuts per engine. The engine is a Hercules HXD, 855 CID. The studs go all the way down to the main bearing caps, so don't mess them up. Keep soaking with penetrating lube such as Liquid Wrench, and tap the studs with a brass hammer to break the rust loose. Good luck and let us know how it turns out. Love my 666's as well.

 

[zak]

There was a tool made for taking aluminum heads off when there was corrosion between the head and the stud. A metal tube that would fit between the head and stud had teeth filled on the end. It was then rotated between the head and the stud to clean out the corrosion. It was a slow process but it worked for me with aluminum. I would think it could work with cast heads.

 

[chrismanby]

Hi guys.
Thanks for all the info.! much appreciated!
Who would have guessed 11/16 x16 thread ! Just the article to ask for at the local hardware store !
I will try and get some bolts in that size, but here in Europe, even in little "politically incorrect" Denmark, they will be hard to find. Will either make them my self or make a brass piece to protect the studs and thread when "motivating" them. I have thought about making tube tool that could fit round the stud and cut its way down through what ever it is holding the thing back, but the head is cast iron and not much room round the stud. Will update later. Thanks for now.

 

[chevy43]

A little heat from the torch around the head where the studs go through might help. (edit, I see you tried that )

I think the head gasket is all copper. It shouldn't have blown. What are the symtoms?

How about put the nuts back on but losen them about two turns and start the engine and rev it. Maybe that would pop the head loose?

Or make a spark plug addapter and pump in grease or oil till the head comes loose?

 

[chrismanby]

Hi, Just a short update on the issue.
The temperature in Denmark has now risen above zero, so work as been resumed.
I have now succeeded in getting the cylinder head off. Simple job really, just add 2 more 2½ ton hydraulic jacks, a coulple more 5 foot steel rods, 2 extra crowbars, 5 steel wedges, 2 more cans of WD40, a lot more heat and the aid of a good friend.
Nice to have someone help you with the job,, saves you crawling around to get from one side to the other, also learnt some new 4 letter words!

I have taken a lot of photos of the job, so maybe I will write an article for our club magazine.

The work is far from finished, as always when you take somthing appart, you encounter new issues to address before you can put things back together again.

On inspection of the cylinder head and the engine, it looked like the head gasget had failed between the No 4 and 5 cylinder. Thus giving the compression pressure access to the water chamber. This is also what was observed when the incident took place. Cooling water hose was blown off the thermostat housing. Mayb the head gasget has had a leak for some time and water has sept to the bolts. The antifreeze liquid has then been boiled and seezed the bolts to the cylinder head. There was much sticky residue and burnt "substance" on the bolts. The bolt holes in the cylinder head had to be reamed out to normal size, in som ecases this was about 1-2 mm.

Anyway, I need to get on with the next issue .... cracked and warped exhaust manifold.

If anyone would like to know more on details of the above issues, please feel free to contact me via the email address.

Chris.

 

[emr]

WD 40 is worthless once u try PBblaster or Kroil in a red can ...spray, there is no comparison at all, U will love it,

 

[quickfarms]

only the wd40 in the spray cans works for rust the stuff in the spray bottle or gallon can does not work on rust.