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| | | | Joined: Jul 2006 Posts: 451 Shop Shark | | Shop Shark Joined: Jul 2006 Posts: 451 | Any good techniques when installing firewall rubber grommets and such? use of gasket sealer, silicon sealants, rubber cement? I will be gradually sealing off the cab with speedo, e brake cables, wiring, clutch rods, choke cables, etc. want them in and to stay obviously. Any tricks or advice for the good seal.
Cavebull | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | | | | | | Joined: Oct 2006 Posts: 843 Shop Shark | | Shop Shark Joined: Oct 2006 Posts: 843 | | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | No goop, just soap as Cletis said. They self retain. The metal cables will stress the grommets big time. The secret there is use clamps to guide/retain the cable as straight thru as possible and keep it from moving at the grommet. If you want to be trick you can make special metal feedthrus for those types of cables or don't use a grommet there.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Mar 2004 Posts: 6,212 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,212 | Sometimes you have to put the grommet on the cable or wire BEFORE you install it in the firewall...dito soap & water if they are tight. Mike B  | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Some even have to be slit, make it diagonal.
Ed
D
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: May 2012 Posts: 574 'Bolter | | 'Bolter Joined: May 2012 Posts: 574 | or heat them slightly in hot water
1949 Dodge Coronet 1955 2nd Chevy 4400 1.5 ton 1955 2nd Chevy 3100 1/2 ton 1955 2nd Chevy 3100 1/2 ton 1957 Chevy 5400 LCF 2 ton 1966 Dodge D100 Sweptline 1968 Chevy P20 stepvan 1969 GMC LWB pickup 1972 GMC Sprint 1974 CP30 shorty bus There are three things that I've learned never discuss with people: religion, politics, and the Great Pumpkin.----Linus Van Pelt Trying to understand the behavior of some people is like trying to smell the color 9  | | | | | Joined: Jul 2006 Posts: 451 Shop Shark | | Shop Shark Joined: Jul 2006 Posts: 451 | looks like soapy water wins. I have used hot water to soften vinyl parts for installing on dive gear... that one slipped my mind totally.Thanks,
Cavebull | | | | | Joined: Jul 2006 Posts: 451 Shop Shark | | Shop Shark Joined: Jul 2006 Posts: 451 | Advice on installing the grommet for the engine harness. Should I pull the dash harness socket through the hole in the firewall into the engine compartment, push the grommet completely over it and install it in the firewall, then push the socket's shoulder back into the grommet - or - seat the socket's shoulder into the grommet first and then soap it and install the assembly into the firewall.
This beast is tight! ANyone cut a small slit in the sheetmetal of the firewall and screwed these things in?
Cavebull | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Up until now it didn't matter what vehicle we were talking about, but now it does if you want a comprehensive answer. It sounds like 60-66. If you are talking 60-66, you had two ways you mentioned, try them both and see which one works. The grommet does have to go over the connector first if it will.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Jul 2006 Posts: 451 Shop Shark | | Shop Shark Joined: Jul 2006 Posts: 451 | 1963 Chevy truck C-10.
Cavebull | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | Up until now it didn't matter what vehicle we were talking about, but now it does if you want a comprehensive answer. It sounds like 60-66. If you are talking 60-66, you had two ways you mentioned, try them both and see which one works. The grommet does have to go over the connector first if it will. FYI: My connector keeps coming out and grommet stays in firewall.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Jul 2006 Posts: 451 Shop Shark | | Shop Shark Joined: Jul 2006 Posts: 451 | From the "for what it is worth" file.
1) Put the firewall grommet in hot water (140-150 was what mine read)to soften it up a bit. Add a bit of Palmolive dish washing soap.
2) From inside the truck, push the dash harness wire connector (socket) though the firewall hole into engine compartment.
3) For leverage, I climbed into the engine compartment, straddled the engine with a foot on each side of the frame, and sat on the valve cover. I recommend removing the oil filler cap. Note: I tried leaning over the radiator and on my side from the fender and just could not push force and leverage.
4) Take the grommet, position it, tapered end, toward the firewall. Push it completely over the dash harness socket onto the wiring.
5) Push the grommet into the firewall hole and use a finger to to push all the way around and outward to make sure the firewall sheet metal is fully seated within the groove of the grommet.
5) Plug the engine harness (plug) into the dash harness (socket). This gives you something substantial to hold onto.
6) Angle the dash socket’s lip into the grommet’s internal groove on the bottom, backside (the area you cannot see from your vantage point), leaving the top forward portion visible. While holding the complete wiring harness connection firmly with the right hand and using the left to hold the right hand and twist, push the assembly into the grommet while simultaneously twisting it clockwise like you were threading it in. This will more than likely require a full 360 turn with constant pressure, but the wiring will take a single turn no problem. You know it is in completely and correctly in if you can turn it back counter-clockwise without it popping out. I actually felt it when it slipped into place in the grommet when I turned it backward
I tried to put the grommet into the firewall with the socket inserted into the grommet first and no luck. Note, this takes no prying or modification of the firewall hole or grommet.
Sorry no pictures but dang sure not taking it to do it again for staged photos.
Leadbelly | | | | | Joined: Jul 2006 Posts: 451 Shop Shark | | Shop Shark Joined: Jul 2006 Posts: 451 | Working my way around the truck replacing gaskets and rubber gone by the wayside. For what it is worth, after doing the body lift of 2 1/2" and looking at the PO's mounting technique of a larger radiator it turned into a total redo. Had a hard time figuring out, but the rad and such were kind of mounted per a 292, V6, or V8. Anyway missing parts, rotted rubber, etc. I made new staples for mounting the rubber to the drip pan and side shields, finishing up the top mount mods and I'll be done and moving on. A few pictures of the process are on the following Flickr page. Radiator rubber replacement Cavebull | | |
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