Lubes, sealants and different approaches... - Page 2

ChrisBennet · ChrisBennet's Garage

Quote:

Originally posted by sand_man
Okay...got my crank case split open early this morning, and was shocked to see that there was NO sealant between the case halves! I guess with all of this worry about what product to use, I thought for sure the factory must use a sealer of some sort. However, all I can see is just perfectly smooth and shiny surfaces! Can someone explain? I know that the case is a precision casting. I've also rebuilt too many aircooled VW engines to count and nearly all of them had a sealant of some sort between the case halves. I think I'm just gonna use a thin coat of 574 and call it a day! Seeing that there's nothing there from the factory, puts a different perspective on it for me.

The amount of sealant on a factory case is very very thin. It sort of looks like a coat of varnish.
-Chris

sand_man · 12-20-2005, 05:00 AM

I'm sure you're right, Chris, but I dunno. There is NOTHING there for me to scrape. When the case separated, there was also no material spider-webbing between the case halves...sort of like the way an old gasket let's go...part of it on one half and part on the other. Don 't get me worng, I still plan to clean the p!ss out of this thing.

code7rpd · 12-20-2005, 07:24 PM

If you use Three Bond 1104 on the case, do you run a bead and spread it or just run a bead?

Carrera3.5L · Carrera3.5L's Garage

Quote:

Originally posted by code7rpd
If you use Three Bond 1104 on the case, do you run a bead and spread it or just run a bead?

My buddy and I spread it using an acid brush:

Ralph

code7rpd · 12-20-2005, 09:52 PM

Thanks for the pics Ralph. It looks like you don't have to use to much and that coat is thin. How long does it take for the 1104 for dry?

helidoc · 12-21-2005, 10:17 AM

It looks like Threebond 1104 is the cheapest of the lot at about $6 per tube. It looks like that is what was used on my motor previously and what the machinist uses that working on it now uses. I think I am going to use the Dow 730 with the probably false thought that it might squeeze in around the seal areas better.

Carrera3.5L · Carrera3.5L's Garage

Quote:

Originally posted by code7rpd
Thanks for the pics Ralph. It looks like you don't have to use to much and that coat is thin. How long does it take for the 1104 for dry?

Yes, you don't have to goop it on, just a nice even layer around the case mating surface. Make sure the surface is clean and flat and doesn't have any nicks, scratches, etc before starting. While it appears thin, you actually should have some 1104 squeeze out when the case is tightened up.

Another good thing about the 1104 in my experience is that it takes a bit longer to dry than the 574 and isn't as messy to work with. It just seems like you have to have to orchestrate the case mating ritual perfectly when using the 574 before it starts to harden and makes me feel like I have to rush which for me means a mistake is more likely to happen.

We tried to time it so the case got mated before quitting time and had the night to cure before starting work on it again the following day.

Ralph

Mike Juzenas · 12-22-2005, 06:55 PM

Quote:

Originally posted by code7rpd
Mike,
Did you take pics in the class. I took some when I took the class a few years ago but lost them on my hard drive. Do you happen to have a pic of the Dow 730 when it is placed on the case? If you do could you post it. If I remember correctly, Jerry used Dow 730 and placed it on the case half that was installed on the stand (4-6 cyl - right case half) but in Wayne's book he mentions that 730 should be placed on the left case half. Or am I wrong and did Jerry put it on the left case. I do remember him making a point to make a wide arc around the oil relief hole on the case.

Jerry did not use the 730 in class since its a class motor and its pretty expensive stuff. He used some red rtv sealant instead. Jerry put the adhesive on the case half that was on the stand and then lowered the other side onto that case half go Jerry put it on the right hand side. Here are the pics that I have of the case joining part. The application seemed to be a bit sloppy but he had an even squeez out at the end.

Cheers,

Mike

ChrisBennet · ChrisBennet's Garage

That orange sealant looks like Loctite 574 or the Wurth equivalent (not RTV).
-Chris

Mike Juzenas · 12-23-2005, 05:46 AM

Quote:

Originally posted by ChrisBennet
That orange sealant looks like Loctite 574 or the Wurth equivalent (not RTV).
-Chris

Hi Chris,

Maybe someone else at the class can remember what he was using...its was something cheaper because the class engine will never be run and was being used just as an example. What he did say is the bead size was typical of what he used when applying the 730.

Cheers,

Mike

sand_man · 12-23-2005, 05:50 AM

It's hard to tell from the pictures, but I think 574 is slightly more traslucent than what is being used. Boy that sure looks sloppy though!

Mike Juzenas · 12-23-2005, 06:17 AM

I think what Jerry was trying to do is show the "route" that he takes with the bead, i.e. what areas to avoid and on what side of the studs to follow. It is a bit sloppy though...mabye its practice from all that quick rebuilds he had to do while on the race teams!

helidoc · 12-23-2005, 11:53 AM

He was using the orange permatex high heat rtv material for demonstration purposes only. He said to use about 1/16th of an inch of the 730.

Mike Juzenas · 12-23-2005, 11:56 AM

[QUOTE]Originally posted by helidoc
He was using the orange permatex high heat rtv material for demonstration purposes only. He said to use about 1/16th of an inch of the 730. [/QUOTE

So I guess this bead was a little thicker?