Head gasket leak?

J

jim d.

New member
Dec 23, 2017
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So folks we've made it a little bit further in our journey. But I fear there's more than just an oil leak somewhere. Today we drove it for about
45mins and parked to go on a hike at Enchanted Rock in Texas. Came back and noticed a few more oil drips than normal. Not a puddle but more drip
spots. We drove down to Fredericksburg and are parked at the Yellowstone campground. Started doing a sneaky oil change and noticed that dipstick had a
bit of rust on it. Run roh. Pop open the cab engine cover and notice that the oil is coming out of the head gasket(I'm pretty sure). This isn't
something I can take care of in campground it's above my expertise without some assistance. Anyone in the Fredericksburg area know any good shops or
recommendations that would be very helpful. I'm going to make some calls in the morning. thanks everyone.
--
Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.
 
Is it possible that you have a valve cover gasket thats leaking? One way to possibly tell where its coming from is to wipe everything down and get
it dry as best you can. Get some baby powder or talcum powder and dust it on the side of the engine you think the leak is coming from. Run the engine
a bit and see where the powder is now wet.

--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
Jim,
Call Dick Patterson (705)325-4554
Tell him I told you to call him.
He can tell you if it is a head gasket leaking or not as there are no oil
pressure at the head.
Be sure to know the differance between the valve cover ad the head.
Should you not be sure call me and I will discribe the two. (800)752-7502.
I'm here to help.

> Is it possible that you have a valve cover gasket thats leaking? One way
> to possibly tell where its coming from is to wipe everything down and get
> it dry as best you can. Get some baby powder or talcum powder and dust it
> on the side of the engine you think the leak is coming from. Run the engine
> a bit and see where the powder is now wet.
>
>
> --
> 77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson
> carb and dizzy.
> Mid Michigan
>
> _______________________________________________
> 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
 
> So folks we've made it a little bit further in our journey. But I fear there's more than just an oil leak somewhere. Today we drove it for about
> 45mins and parked to go on a hike at Enchanted Rock in Texas. Came back and noticed a few more oil drips than normal. Not a puddle but more drip
> spots. We drove down to Fredericksburg and are parked at the Yellowstone campground. Started doing a sneaky oil change and noticed that dipstick had
> a bit of rust on it. Run roh. Pop open the cab engine cover and notice that the oil is coming out of the head gasket(I'm pretty sure). This isn't
> something I can take care of in campground it's above my expertise without some assistance. Anyone in the Fredericksburg area know any good shops or
> recommendations that would be very helpful. I'm going to make some calls in the morning. thanks everyone.

Jim,

You are in Texas, you have a copy of the Black List. (If you did not download it before you left home, you can still and we will say you did.) There
are about 40 members in Texas, start tracking on a map and calling....

Now, to your problems:
It is unlikely that you have a headgasket oil leak. (There is no high pressure oil in the deck face.) It is very possible that you have a bad valve
gear cover gasket. While it is still a PITA, it is much more serviceable. It also could be that your crankcase pressure control is fouled and so you
have higher pressure at all the gaskets than should be there.

Do us a favor, get some paper towels and brake cleaner and try to get a good look at where the leak is. I have expensive stuff I use because I could
"acquire" it from part employers, but it is not that different than any spray on powder deodorant or foot powder spray. Between those two, you should
be able to identify the leak location. Do you have your GMC Thumbdrive? Look in the maintenance manuals for a picture that shows where the leak is
and post the manual number (there are 3)and the figure number. Then we will all know exactly what you are seeing.

If it is a cylinder head cover (valve gear cover), before you do anything else, get the right small socket on an extension and the shortest ratchet
that you can and try to snug up the fasteners. If you over tighten these, they will leak for sure. I hope you have a GMC Belly Board, you will need
it.

Back to the high crankcase pressure. There is a PCV valve plugged into the right side cylinder head cover. These can go bad and cause high crankcase
pressure. When you are under there next, pull that device out of the rubber grommet it is in and do this very precise and technical performance test:
Shake it.... If it rattles, it is good. If it does not, replace it.

Rust on the dipstick is common. It is because combustion by-products go up the tube and condense on the bare metal.

Good Luck and keep us posted.

Matt - the refugee from engine dyno land

--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
> Jim,
> Call Dick Patterson (705)325-4554
> Tell him I told you to call him.
> He can tell you if it is a head gasket leaking or not as there are no oil pressure at the head.
> Be sure to know the differance between the valve cover ad the head.
> Should you not be sure call me and I will discribe the two. (800)752-7502.
> I'm here to help.
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.appliedgmc.com
> 1-800-752-7502

Jeff,

See those numbers?
Load them both in your speed dial Now.
JimK has pulled the (sensitive male anatomy) out of the fire for most of us at one time or another.
Dick Paterson could probably sit down and write a copy of the engine side of the manual (with the required corrections) from memory.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Don Virta Garage in Cedar Park, TX, 512-921-8142 is only 90 miles from you. It's on the north side of Austin.
He's pretty good on GMCs.
But, I don't think you've got anything to worry about. AND, there's most likely someone in Fberg that wouldn't mind tightening things up for you. What's your phone number? I'll have Steve McAnally reach out. He probably knows of a good local shop if you want it.

We gonna see you in Kerrville on the 25th?

Billy

-----Original Message-----
From: On Behalf Of Jim D.
Sent: Monday, January 15, 2018 6:01 PM
Subject: [GMCnet] Head gasket leak?

So folks we've made it a little bit further in our journey. But I fear there's more than just an oil leak somewhere. Today we drove it for about
45mins and parked to go on a hike at Enchanted Rock in Texas. Came back and noticed a few more oil drips than normal. Not a puddle but more drip
spots. We drove down to Fredericksburg and are parked at the Yellowstone campground. Started doing a sneaky oil change and noticed that dipstick had a
bit of rust on it. Run roh. Pop open the cab engine cover and notice that the oil is coming out of the head gasket(I'm pretty sure). This isn't
something I can take care of in campground it's above my expertise without some assistance. Anyone in the Fredericksburg area know any good shops or
recommendations that would be very helpful. I'm going to make some calls in the morning. thanks everyone.
--
Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Back to the high crankcase pressure. There is a PCV valve plugged into the right side cylinder head cover. These can go bad and cause high crankcase
pressure. When you are under there next, pull that device out of the rubber grommet it is in and do this very precise and technical performance test:
Shake it.... If it rattles, it is good. If it does not, replace it.

[/quote]

There is also a breather filter on one of the valve covers. They can also get plugged and cause high crankcase pressure leading to excessive oil
seeping out various places and in extreme cases can lead to excessive oil consumption. Don't ask how I know this...;).


--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Sorry. This was meant to be private.
bdub

-----Original Message-----
From: On Behalf Of Billy Massey
Sent: Monday, January 15, 2018 8:25 PM
Subject: Re: [GMCnet] Head gasket leak?

Don Virta Garage in Cedar Park, TX, 512-921-8142 is only 90 miles from you. It's on the north side of Austin.
 
When you have the valve cover removed from the engine, get a small hammer and flatten out the underside of the bolt holes. Overtightening will distort
them. A good place for minor messy leaks.
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG
 
I also seriously doubt that you have a head gasket leaking oil. There is no pressurized oil at that head seam. I would buy a new PCV valve and
install it (around $3.00) and less than a minute or two to do it. I would go around the valve cover bolts bolts and LIGHTLY try to tighten them with
a SHORT handled ratchet. If you turn them too tightly you will bend the valve cover lip where the bolts go through the holes and it will have to be
removed and straightened.

If you can not tell exactly where the oil is coming from, I would take either some spray engine cleaner or brake cleaner and wash away the oil in the
area. You might want to clean it up even if you can tell where it is coming from.

Which side is leaking? If it is the driver's side it is an easy job to replace the gasket if necessary. Passenger side is a little more difficult
because the AC compressor bracket is in the way and needs to be removed. I would get new gaskets with a steel core. If no one else posts the part
number I'll go find it.

When replacing, clean up the covers and examine the holes. and put a light coat of silicone on the lip of the cover. Use the valve cover bolts to
keep the gasket aligned and place the cover and gasket on a flat surface to dry overnight. By morning the gasket should be stuck to the cover as the
silicone set up.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Sorry for the late response to everyone. Couldn't get the internet to work after I posted and I get very limited service with my phone. Thanks
everyone for the info. Im going to wipe the engine down as best I can as we are parked currently and its sleeting/snowing out and surprisingly cold.
Born and raised in NH you never think that Texas would get this cold or snow. Now I might have jumped to conclusions with the head gasket leaking and
slightly panicked with the oil sprayed on stuff. Now my valve covers are blue which are bolted to the cylinder heads which are bolted to the engine
block. It looked like a majority of the oil is below the cylinder heads and it appears to be on both sides. Ill check the PCV valve as well when Im
cleaning things up. This being our first major excursion(3months in) I get a little nervous with any engine problems as its not my strong suit. Im an
autobody technician by trade so I can figure my way around cars fairly quickly. Just out of my comfort zone a little bit with old motors. I have the
blacklist saved but I couldn't get any internet service on my phone which its saved on but ill be calling Dick Patterson here in a few. Once again
thanks for all the support guys. My number is (603)235-1576
--
Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.
 
Remember that drips are annoying but don't necessarily indicate anything
worse than a leaky this or that. Since you are new to old engines, you may
not realize just how much old engines leak compared to new engines. It's
possible but not easy to stop all the oil leaks--too many seams bolt sheet
metal to iron. It was pretty normal in the day for there to be evidence of
oil drips. New engines are quite different in that regard, and usually
don't leak unless something is wrong.

If you are using oil at an acceptable rate (a quart no more often than
every 500 miles), and if the engine is running good with reasonable oil
pressure, then I don't think you have a serious problem.

I had leaks from the front timing-chain cover (which is sandwiched between
the water pump and the block)--it's plate steel and subject to distortion,
especially where it meets the oil pan.

If you have a lot of blow-by, the crankcase will get pressurized despite
the positive crankcase ventilation (which is what PCV means). This will
blow oil out seams that are not at all designed to withstand much pressure.
Blow-by is the result of worn rings, but that just means the engine is a
bit tired, not that it is in immediate danger.

So, my opinion is to believe the smoothness of the engine, the gauge
readings, and the oil consumption to a greater extent than drips.

Rick "who just put in a fresh engine, and MIGHT not have leaks at the
moment" Denney

> Sorry for the late response to everyone. Couldn't get the internet to work
> after I posted and I get very limited service with my phone. Thanks
> everyone for the info. Im going to wipe the engine down as best I can as
> we are parked currently and its sleeting/snowing out and surprisingly cold.
> Born and raised in NH you never think that Texas would get this cold or
> snow. Now I might have jumped to conclusions with the head gasket leaking
> and
> slightly panicked with the oil sprayed on stuff. Now my valve covers are
> blue which are bolted to the cylinder heads which are bolted to the engine
> block. It looked like a majority of the oil is below the cylinder heads
> and it appears to be on both sides. Ill check the PCV valve as well when Im
> cleaning things up. This being our first major excursion(3months in) I get
> a little nervous with any engine problems as its not my strong suit. Im an
> autobody technician by trade so I can figure my way around cars fairly
> quickly. Just out of my comfort zone a little bit with old motors. I have
> the
> blacklist saved but I couldn't get any internet service on my phone which
> its saved on but ill be calling Dick Patterson here in a few. Once again
> thanks for all the support guys. My number is (603)235-1576
> --
> Jim DeMellia and Jen Radefeld and our cat Ickis
> NH natives
> 1975 GMC “Palm Beach” ,455, her names Linda
> Full time RVers exploring the beautiful and unusual parts of the country.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
'73 X-Glacier 230 "Jaws"
Northern Virginia
Offlist email: rick at rickdenney dot com
 
Once again guys a day late and dollar short. Didn't stick around Fredericksburg very long. As much as we aren't on a timeline we still have places we
are supposed to be stopping at certain times. So cliff notes. I tried to call Dick Patterson to no avail, not a big deal at least I have his number
for future issues. I got a hold of a buddy back home old gear head. He reiterated what you guys said, these motors are going to spit at you growl and
sometimes question your sanity but if it sounds like it's running good it probably is and she sounds great when running. . I tightened all the valve
cover bolts which were all loose. I crawled under and tightened what I could get at on the oil pan which were also loose and then the tranny cover
bolts which were also loose. Seemed to help a little with the "drips". Little bit of oil at the base of the distributor cap as well after I cleaned
the engine up. Still seem to get some extra dripping in the oil filter area, just above it from what I can see. Also oil pressure gauge shows just
above half while driving and when idling drops down to low. Going to dig out the original manual about the oil pressure which I vaguely remember being
in there. Thanks again guys
--
Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.
 
Be very careful on overtightening all of those bolts. One of the main causes of valve cover leaks is that they were over tightend and deformed the
metal cover itself. One of the replies on this thread was suggested to remove the valve cover and carfully pound out the bases where the bolt holes
are to make sure they are flat. Over tight can cause more/worse leaks. The torque values should be in the manual, but Im pretty sure they are in Inch
pounds, not foot pounds. Good luck on your continuing travels. Good stuff.

--
77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy.
Mid Michigan
 
Now when I say loose some of them I could of taken off with my fingers. Tightening the valve cover back down I just snugged them back on. Didn't get
aggressive with any of the hardware mentioned.
--
Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.
 
Next time you change the oil, remove the oil filter adapter and check the o-ring between the adapter and the block. Not actually an o-ring because the
OEM ring was actually square. Many of these have been replaced by the square o-ring from the old oil filter. Not a 100% solution, but will work. It
stands a little proud of the groove and may seep oil.
Parker has an o-ring that works, but you have to find a Parker supplier that will 'sell' you just one. Local Parker dealer gave me one for free. He
said the cost of selling it far exceeded to cost to process the sale. I seem to remember it as a number 4 in size.
I would just take the removed oil filter adapter with me to the Parker supplier and see if he is willing to match it with his current stock on hand.
It is not square, but will provide a good seal.
I'm enjoying following your adventure.
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG
 
There is also a Dorman part number available for that gasket. It was in stock at my local auto parts store. Unfortunately the box with number on it
is 11 miles from here so I cannot supply the number.

If you want it you can search this forum for it. I know it has been posted here several times.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
G'day,

I can! :-)

http://www.gmcmhphotos.com/photos/g6677-oil-filter-base-to-oil-cooler-adapter-sealing.html

Regards,
Rob M.
The Pedantic Mechanic
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 Ken Burton
Sent: Sunday, January 21, 2018 9:14 PM
To: gmclist
Subject: Re: [GMCnet] Head gasket leak?

There is also a Dorman part number available for that gasket. It was in stock at my local auto parts store. Unfortunately the box
with number on it
is 11 miles from here so I cannot supply the number.

If you want it you can search this forum for it. I know it has been posted here several times.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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GMCnet mailing list
Unsubscribe or Change List Options:
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Thanks Rob,

Dorman 917-036
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Thanks guys. Next oil change I'll take a look at changing the gasket. So far after tightening everything back up that was extremely loose, the oil
drips have subsided to a reasonable amount. Now tho it seems like my "granny gear"(downshifting when going up hills or passing) is starting to
struggle. It will downshift and kick the secondary on carb open only if I put my foot into the floor. We were coming out of Caprock canyon the other
day and climbing a hill and I was nervous we weren't going to make it. We maxed out at 20mph any more Hill and we would have been crawling.
--
Jim DeMellia and Jen Radefeld and our cat Ickis
NH natives
1975 GMC “Palm Beach” ,455, her names Linda
Full time RVers exploring the beautiful and unusual parts of the country.
 
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