GM 3100 head question

fmt1081

ase gold card holder
Aug 15, 2009
12
0
0
IA
it's threaded pipe sealant (white stuff) I always used indian head gasket shelac. if not used it will seep coolant into rocker area. that's my experience. worked on some 3.1's with cracked blocks they made milkshakes though.
 

Vrabel

TOYAHOLIC
May 22, 2008
3,434
0
0
57
Hewitt, NJ
its also good to use on water outlets and pumps. anyplace you fasten a coolant related item. if you ever did a ford v-8 water pump, you'll really understand the importance of using this stuff.
 
Jun 28, 2007
3,259
0
0
NE Pa
The white stuff with teflon is the best. Buicks are known for studs leaking and everyone uses magic stuff....I use the white pipe dope with teflon and have never had a leak and I hust have done the heads at least 20 time:)
 

Vrabel

TOYAHOLIC
May 22, 2008
3,434
0
0
57
Hewitt, NJ
I think the stuff from permatex in a tube is called PST. funny, ya use the stuff so often and cant remember actual name.
 
Jun 28, 2007
3,259
0
0
NE Pa
I think the stuff from permatex in a tube is called PST. funny, ya use the stuff so often and cant remember actual name.

I grab the stuff from work:confused: I started using high temp light blue stuff they use for low pressure steam fitting and its working well. But I hear ya, I can go to the store and know exactly what I need and tell you where it is but I'de be damned if I could tell you what it says on the lable:spit:
 

Cougar281

Well-known member
Sep 11, 2006
1,806
249
63
St Louis, MO
Got the headbolts today, and there's one different one. All the bolts that came off where the same. Its short, so it goes outside the valvecover. Any ideas on this "oddball"?
 

Attachments

  • IMG00120.jpg
    IMG00120.jpg
    52.7 KB · Views: 5

Cougar281

Well-known member
Sep 11, 2006
1,806
249
63
St Louis, MO
is that threaded on top? maybe for a acc mount on a different model

Nope. Only thing I can figure is MAYBE an extra grounding point...

Vrabel, you said that it's not nessicary to shim the rockers after resurfacing; Does that apply to switching the heads as well? I want to put the head that was on the rear of the motor on the front as one of the spark plug holes *might* be questionable (it's ok at this point. I just want to be able to keep an eye on it), so I want it where it can be gotten to if needed fairly easily (much easier than it would be in the back). If the lifters are hydrolic, I'd think that would take up all the adjustment needed for the pushrods, and the rockers would only need to be shimmed to maintain proper lash if the valves where changed or they got a valve job.
 
Last edited:

Mike

hmmm....
Feb 17, 2007
2,184
0
36
San Angelo, TX
Some 3.1's, front wheel drives, had the shorter bolt or the threaded stud/bolt due to the wishbone strut mount to the radiator bracket. That bolt is to center that bracket.
 
Last edited:

Cougar281

Well-known member
Sep 11, 2006
1,806
249
63
St Louis, MO
Yet another question :rolleyes:.

Do the head bolt holes (in the block) need to be absolutely bone dry? I blew out what coolant was in them, but there's still some moisture in there. They might be dry by mid-tomorrow, but in case they aren't, I'd like to know if I can put the heads on with some moisture in there.

Also, what's the thread sealant for again? Reason I ask is not one of the bolt holes are open to the coolant. They're all dry.
 
Last edited:

Vrabel

TOYAHOLIC
May 22, 2008
3,434
0
0
57
Hewitt, NJ
thread sealant is for bolts that go through water passages. good to put on head, waterpump, and t stat bolts.
 

Cougar281

Well-known member
Sep 11, 2006
1,806
249
63
St Louis, MO
Ok guys, motors mostly back together. Another unknown... How the heck does the part in the attached pic go together? Obviously, the black "heater pipe" goes into the threadded fitting and gets locked in place by the plastic clip, but how does it seal? The O'Ring and flat rubber "washer" came out of it. The thing is, the "washer" doesn't appear to do anything; when it's inside between the "heater pipe" and the fitting, it's not tight, it just rattles around, and if I put the O-ring inside the lip of the aluminum fitting, when I push the "heater pipe" into the fitting, it just pushes the O-Ring in and doesn't get a good seal. So how do I put it together so it seals? I can't find any exploded views ANYWHERE.
 

Attachments

  • IMG00126.jpg
    IMG00126.jpg
    31 KB · Views: 4

Mike

hmmm....
Feb 17, 2007
2,184
0
36
San Angelo, TX
Ok guys, motors mostly back together. Another unknown... How the heck does the part in the attached pic go together? Obviously, the black "heater pipe" goes into the threadded fitting and gets locked in place by the plastic clip, but how does it seal? The O'Ring and flat rubber "washer" came out of it. The thing is, the "washer" doesn't appear to do anything; when it's inside between the "heater pipe" and the fitting, it's not tight, it just rattles around, and if I put the O-ring inside the lip of the aluminum fitting, when I push the "heater pipe" into the fitting, it just pushes the O-Ring in and doesn't get a good seal. So how do I put it together so it seals? I can't find any exploded views ANYWHERE.

I believe you may be missing one more plastic piece unless you have a groove down a ways in the adapter for the oring. The o ring goes in then the plastic round pressure ring. The other piece is an orifice and should go in first.
 
Last edited:

Cougar281

Well-known member
Sep 11, 2006
1,806
249
63
St Louis, MO
I believe you may be missing one more plastic piece unless you have a groove down a ways in the adapter for the oring. The o ring goes in then the plastic round pressure ring. The other piece is an orifice and should go in first.

Hmmm... That's all that came out, and there doesn't appear to be any groove for the O-Ring.... Think I would be better off getting a brass nipple and replacing the aluminum part and pipe with some heater hose?
 

Mike

hmmm....
Feb 17, 2007
2,184
0
36
San Angelo, TX
Hmmm... That's all that came out, and there doesn't appear to be any groove for the O-Ring.... Think I would be better off getting a brass nipple and replacing the aluminum part and pipe with some heater hose?


So long as the o ring stays in place and seals, that may be all that is necessary. I was just thinking or I thought I remembered another piece. Sorry about that.


The brass fittings, that will work however, that orifice should be incorparated if possible. Autozone, O'reilly (sp), Napa and Advanced all have the adapter in stock for cheap. You need some pressure differential to keep the heater core from clogging over time. No big deal though. Just a thought.
 

Cougar281

Well-known member
Sep 11, 2006
1,806
249
63
St Louis, MO
It's ALIVE!! :frank: Looks like I'm going to have to get a replacement O2 sensor as it's throwing a P0134. It's got two other codes that I can't seem to figure out for sure what they are. They are P1641 & P1671. Mitchell says 1641 is a MIL circuit fault, but there seem to be several different possible defenitions, and 1671 isn't listed in Mitchell. Any thoughts on those two?