A few 20/2 assembly questions

[bschwartz]

I'll apply the sealing info now, as I'm in the middle of a rebuild on my 6/1.

[billswan]

Well guess what I am struggling with some of the same problems. I thought I sealed the threads but I guess not well enough or I just plane missed some. I have about 800 hours on my engine and at about 650 to 700 it started to turn into a leaking mess.  I used cheap rtv and must have been much to stingy with it. It seams you fix one leak here and another one springs up somewhere else.

I am thinking I will have to pull the pump side flywheel and pull the casting that the injector pump bolts to. Seems not only the studs are leaking but the gasket is also. Black mess.......................

Billswan

[flywheel]

I'll apply the sealing info now, as I'm in the middle of a rebuild on my 6/1.

Here is a pretty good way to seal leaks at bolts and studs on the listeroids.  It is best done during a rebuild or whenever your engine is apart.  The parts to be sealed must be oil free, dry and clean. 

This is done from inside the crankcase while the engine is being reassembled.  I have used this method on my listeroid and it works well. 

It works well on any bolt or stud that threads into the crankcase. 

Take Permatex and apply it to any bolt or stud where it projects into the crankcase to seal the threads.  Do this after the bolt or stud is installed.  Where the stud or bolt does not project into the crankcase enough and is in a recess use a small mini brush to seal the threads.

The kinds of Permatex I use is the old paste style stuff, unaffected by gas or oils.  I have some of this stuff that is over 25 years old and it still is good.

This seals the threads and prevents oil from leaking from the inside traveling along the stud or bolt.
                                                                                                                                                              flywheel

[bschwartz]

Would this be a good application for the ace hardware stick stuff I've seen mentioned before?

[flywheel]

Would this be a good application for the ace hardware stick stuff I've seen mentioned before.

No - this is not the right kind of sealer.  Permatex works well because it unaffected by water, gas and oils.  If you ever get it on your hands you know how hard it is to remove. 

You want to seal the area between the threads in the block and studs or bolts AFTER they have been installed.  It prevents oil from traveling out thru the loose fitting Indian fasteners.

The more oil you can keep inside your engine means it will be cleaner on the outside. 

The Ace sealer is very good stuff,  it may work if used like you would on pipe fittings.  I have not used it for trying to seal after stud and bolt installation.
                                                                            flywheel

[bschwartz]

Flywheel, my thought was to use this in the threads of the studs during assembly, not after the fact.
Is there any reason you suggest sealing AFTER installation instead of during?

[flywheel]

Flywheel, my thought was to use this in the threads of the studs during assembly, not after the fact.
Is there any reason you suggest sealing AFTER installation instead of during?
[/quote

Yes, you can use the Ace stuff that way,  its a very good sealant. 

I should have added that the Permatex is used in addition to whatever sealer you used DURING assembly.

The Permatex is just another way of getting extra protection against leaks.  That why you would want to  apply it AFTER the studs and bolts have been installed. 
                                                                               flywheel

[flywheel]

This is what I use for a sealer AFTER fasteners have been installed.  Permatex #1, thick like toothpase but probably does not taste as good!
                                       flywheel

[vdubnut62]

I'm probably going to get horselaughed out of here......but I use the old Indian Head gasket shellac on leaky threads. That stuff sets up and is there for the duration.
  Caution! If you DO put it on a gasket (which I don't), it will also be there for the duration. You may have to throw the part in the fire to burn the stuff off.
Ron.

[mbryner]

So I've been struggling with leaks on my 6/1 recently.   Just yesterday I used teflon based pipe thread sealant on the head bolts and on the rocker arm assembly bolts.  The head bolts aren't leaking anymore (if they were).   It still leaks coolant between the rocker arm assembly and the head.   The teflon based stuff didn't work for that.   Should I try a bunch of RTV silicone or copper-color form-a-gasket stuff next?  That coolant seeping into the valve guides can't be good.

Marcus

[bschwartz]

I had rocker arm leaks too.  It was a bad head gasket seal.

[Tom Reed]

Ditto and ditto. A bit of copper coat between the layers of the gasket solved the problem.

[mbryner]

Since I don't have leaks outside around the head gasket, I guess I try copper coat between rocker arm ass'y and head first, before taking head off again.   Sucks to lose your head....

[cgwymp]

I'm using a slightly different approach -- I've removed all studs, cleaned all the studs & holes with brakleen, and then reinstalled them all with blue Loctite. This will seal them and also keep them from loosening up -- I'm assuming that like other studs they should only be installed hand tight!