Oil Pan Gasket

DetroitDan

DetroitDan

Member
Mar 28, 2017
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I am getting very close to getting the Chief ready for use.

When I bought it, I noticed the oil pan had a coating of oil and grime.

When I changed the oil, I could see that the pan gasket is the source of the leak.

The Mobil 1 10W-30 is coming out a little more readily than the old oil.

I read the instructions in X7425 -- the job looks pretty horrible.

1) Is pulling the final drive and trans a reasonable "driveway" job?

2) Does anyone have any idea what it would cost to have the gasket replaced professionally?

Dan "Dripping in Detroit" Wallace

--
Dan Wallace
Detroit Metro
1974 Canyon Lands 260
Headers, 3.55, 16"
Floor plan 26-9
 
Dan,
When you line up all the small equipment needed, it is not that big of a
job to do.
You do need to create space by separating the trans from the block, which
will help to clear the final drive.
Get under there and look so you get a better idea.
Let me know when you'll be doing it as we can assist you via phone and
smart phone photo even on weekends and evenings.

On Tue, Jul 25, 2017 at 6:24 AM, Dan Wallace
wrote:

> I am getting very close to getting the Chief ready for use.
>
> When I bought it, I noticed the oil pan had a coating of oil and grime.
>
> When I changed the oil, I could see that the pan gasket is the source of
> the leak.
>
> The Mobil 1 10W-30 is coming out a little more readily than the old oil.
>
> I read the instructions in X7425 -- the job looks pretty horrible.
>
> 1) Is pulling the final drive and trans a reasonable "driveway" job?
>
> 2) Does anyone have any idea what it would cost to have the gasket
> replaced professionally?
>
>
> Dan "Dripping in Detroit" Wallace
>
>
> --
> Dan Wallace
> Detroit Metro
> 1974 Canyon Lands 260
> Headers, 3.55, 16"
> Floor plan 26-9
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
Forty years ago, I had this 68 Olds Cutlass wagon with a 350 and automatic. It had a very bad oil leak from the pan just below the front main seal. I
was putting in a quart every 100 miles. It looked like to fix it that I was going to have to...at a minimum, loosen the trans and slide it back, and
lift the engine to get at the pan. Then there was the frame and all of the steering that was in the way. It was going to be an awful job. So instead I
cleared out as much of the old gasket as l could with a knife, and took brake cleaner and cleaned the area thoroughly. Then, took silicone gasket
sealer and using my fingers squished the sealer into the opening. Smoothed out the gasket sealer and let it set for two days. I drove that car
another 10 yrs to 180K miles. Never leaked another drop from that spot. Not saying that this is the answer...just saying...what ya got to loose? If
it doesn't work, you were going to take it apart any way, and the only cost is a tube of gasket sealer and a comparatively minor amount of time.

Just my relatively informed, off the cuff, back yard mechanic, gut level, eyeball it up and guestimate, opinion....that's all...
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Dan,

Hoo bloody ray! You read the manual, good on yah, Mate!

I would suggest you get your GMC up off the ground and go through the manual's procedure step by step to ascertain if the task is
within your skill set and if you have the tools and equipment to do the job.

Check the Black List to see if there are any fellow GMCer's willing and able to help you do it.

Call Cinnabar (they are 90 miles from Detroit in Sandusky) and ask them what they charge to do the job. Don't be surprised if they
are reticent to quote, tell them all you want is a budgetary (ball park) figure for financial planning purposes.

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Dan Wallace
Sent: Tuesday, July 25, 2017 11:24 PM
To: gmclist
Subject: [GMCnet] Oil Pan Gasket

I am getting very close to getting the Chief ready for use.

When I bought it, I noticed the oil pan had a coating of oil and grime.

When I changed the oil, I could see that the pan gasket is the source of the leak.

The Mobil 1 10W-30 is coming out a little more readily than the old oil.

I read the instructions in X7425 -- the job looks pretty horrible.

1) Is pulling the final drive and trans a reasonable "driveway" job?

2) Does anyone have any idea what it would cost to have the gasket replaced professionally?

Dan "Dripping in Detroit" Wallace
 
> Forty years ago, I had this 68 Olds Cutlass wagon with a 350 and automatic. It had a very bad oil leak from the pan just below the front main
> seal. I was putting in a quart every 100 miles. It looked like to fix it that I was going to have to...at a minimum, loosen the trans and slide it
> back, and lift the engine to get at the pan. Then there was the frame and all of the steering that was in the way. It was going to be an awful job.
> So instead I cleared out as much of the old gasket as l could with a knife, and took brake cleaner and cleaned the area thoroughly. Then, took
> silicone gasket sealer and using my fingers squished the sealer into the opening. Smoothed out the gasket sealer and let it set for two days. I
> drove that car another 10 yrs to 180K miles. Never leaked another drop from that spot. Not saying that this is the answer...just saying...what ya
> got to loose? If it doesn't work, you were going to take it apart any way, and the only cost is a tube of gasket sealer and a comparatively minor
> amount of time.
>
> Just my relatively informed, off the cuff, back yard mechanic, gut level, eyeball it up and guestimate, opinion....that's all...

One other thing that might help seal it as you are applying the silicone. Attach a vacuum cleaner to the hose from the valve cover port going to the
air cleaner. That will put negative pressure on the crank case and draw in the silicon in the leaking area. I did this one time on an intake
manifold end seal that was leaking oil. I let it run for about an hour. Then I let it set up (dry) for about a day.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
^^^ Im with Larry and Ken. Have rigged oil pan leaks likee that before. Use the good stuff.
Also, slight ly tighten the pan boltsonce it sets up
Key is getting it clean then cleaning again.
Pulling some vaccuum is an idea worth trying.

--
76 Glenbrook
 
And of course I'm kicking myself for NOT doing the pan gasket while I had the trans out...

When the trans and final drive are out, you have full access to the whole pan. I didn't even think about it until a week later.

Oh well. Next time.

--

Jared Kohl
Rappahannock County, VA
1973 Painted Desert "Onslow"

I have yet to experience what it takes to do a pan gasket. Most people talk about pulling the engine.

Even dropping the tranny/final drive, i wonder how you can get at the front well enough.

Hopefully someone will chime in on a success story on a pan gasket and how it was accomplished.
--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/

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Unsubscribe or Change List Options:
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Jared,

You have to raise the engine as the front of the pan hits the main bearing cap and the cross member and won't come out.

Regarding the oil pan gasket C. Boyd noted:

Auto-Zone shows Fel-Pro oil pan gasket # OS30471C as standard for the 350 diesel and is shown as optional for the 455 and 403.

This gasket also has a steel core which won't extrude.

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Jared Kohl
Sent: Wednesday, July 26, 2017 9:48 AM
To: gmclist
Subject: Re: [GMCnet] Oil Pan Gasket

And of course I'm kicking myself for NOT doing the pan gasket while I had the trans out...

When the trans and final drive are out, you have full access to the whole pan. I didn't even think about it until a week later.

Oh well. Next time.

--

Jared Kohl
Rappahannock County, VA
1973 Painted Desert "Onslow"

I have yet to experience what it takes to do a pan gasket. Most people talk about pulling the engine.

Even dropping the tranny/final drive, i wonder how you can get at the front well enough.

Hopefully someone will chime in on a success story on a pan gasket and how it was accomplished.
--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/

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Unsubscribe or Change List Options:
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_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Thank you all for your great suggestions!

I am going to start with the super clean, vacuum, sealer trick.

I'll bet it is going to be adequate to make it through December.

It's worth a try!
--
Dan Wallace
Detroit Metro
1974 Canyon Lands 260
Headers, 3.55, 16"
Floor plan 26-9
 
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