The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 12-21-2005, 08:26 PM   #1
formula_raider
Registered User
 
Join Date: Nov 2005
Location: San Marcos, Tx
Posts: 62
Started new engine for 1st time

Today I was a nervous reck...always get nervous when I start an engine for the first time. I double checked all my connections and fluids, primed the engine and it kicked over and stumbled until I adjusted the timing by ear then I revved it up to 2,000 RPM to break in the cam. All the time I was looking for any leaks. I had made up stainless steel braided transmission lines and power steering lines and was worried that I did them correct. No leaks in engine, transmission, power steering, etc.....then I saw it!!!! Very, very small drip comming from the front of the cylinder head right by the #1 cylinder. It was anti-freeze....it looks like the cylinder head gasket failed and has an extremely slow leak. Temperature stayed reasonable and I broke the cam in. Changed the oil to see if any water got into the oil.. but it is hard to tell with all the extra cam lube and assembly lube that mixed with the oil. I am sooooo PI**ED. It took me 4 years to finish this engine, and it really sounds good. I went with the Felpro steel shim gasket to get my compression ratio up....it is a thin gasket but I took that in consideration and had my NEW vortec heads surfaced to make sure the contact was smooth. And I used new ARP bolts. These gaskets are used all the time in "hot rod" magazines. Does anybody have any idea what I should do.....is it worth taking the header and valve cover off and trying to retorque the head. Or am I going to have to bite the bullet and replace the head gasket again. Its enough to make a man want to quit the project.
Attached Images
  
formula_raider is offline   Reply With Quote
Old 12-21-2005, 08:41 PM   #2
formula_raider
Registered User
 
Join Date: Nov 2005
Location: San Marcos, Tx
Posts: 62
Re: Started new engine for 1st time

The color is PPG "Screaming Yellow". I think you will be OK if you use a composition gasket, they are thick to fill in head flaws, I had to go the steel shim way because I wanted my compression around 9.25:1. I put the heads on myself, they look good.....the block however was not smoothed BUT it is a brand new block.
formula_raider is offline   Reply With Quote
Old 12-21-2005, 08:55 PM   #3
FormerMember
Account Suspended
 
Join Date: Feb 2004
Posts: 3,051
Re: Started new engine for 1st time

I would pop the valve cover and torque the head down, before I yank the head.
FormerMember is offline   Reply With Quote
Old 12-21-2005, 09:33 PM   #4
davidh
Senior Member
 
davidh's Avatar
 
Join Date: Feb 2004
Location: Ponca city now kingfisher Oklahoma
Posts: 1,221
Re: Started new engine for 1st time

All the motors I've done I've never had that problem. I had to change out a front seal before however. They need to get hot to seal. retighten everything and check again.
davidh is offline   Reply With Quote
Old 12-21-2005, 10:07 PM   #5
phantom dually
Project92 SWB stepside
 
phantom dually's Avatar
 
Join Date: Feb 2003
Location: Louisville KY
Posts: 4,793
Re: Started new engine for 1st time

I would recheck the head torque also. How much compression diffrence will you see going with the thicker gasket??
__________________
92 C1500 stepside 496 Stroker Competiton Engineering Ladder bars/QA1 coilovers. Dana 60 rear with 4.10 gear and posi. Bonspeed Palisade 20x12 in rear w/335/30/20 and 20x8.5 front w/245/40/20. 5/8 drop with Belltech springs/DJM spindles/drop shocks. WWS Progress thread http://67-72chevytrucks.com/vboard/s...d.php?t=140448
phantom dually is offline   Reply With Quote
Old 12-21-2005, 10:09 PM   #6
Green Machine
Senior Member
 
Green Machine's Avatar
 
Join Date: Jul 2004
Location: Estherville, Iowa
Posts: 3,371
Re: Started new engine for 1st time

I have always used the steel shim head when possible and have not had a problem so far(now watch my next one f**K up). Some things to ponder ---Was that the plain steel gasket or the coated one ?? Is your torque wrench accurate ? Don't know about the coated gasket, but the plain steel ones need to be coated with something before assembly, I always use a spray product called copper coat. Did you run a tap through the bolt holes in the block ?? Did you put a non hardening sealer like permatex on the head bolt threads ? If the block was decked did they put the head alignment pins back in the block ?Did you torque down in steps like 40 55 65 ? And in the proper sequence ?? I always tighten the short bolts to 65 and the long bolts to 70.

You could use bars leak, if you know you did everything else right, hate to use that stuff unless in a real bind though. If you know everything is straight and follow the steps above a shim gasket will not leak. If all else fails GM and
maybe some others make a compostion gasket that is only .28 thick so it won't mess up the quench distance "too" bad.

Could intake be leaking a bit and running down there ?? Just some thoughts...

Look at the good side - at least it is warm enough there that you CAN work on your truck if you want/need too.....not here, prolly can't do squat until spring, now that pisses ME off...........lol
__________________
1968 C10 307 3spd Long Fleet ------ http://67-72chevytrucks.com/vboard/s...d.php?t=201103
1970 C10 305 Super T10 Long Fleet --- http://67-72chevytrucks.com/vboard/s...d.php?t=202285
1971 C20 383 TH350 Dana Posi ----- http://67-72chevytrucks.com/vboard/s...d.php?t=206894
2001 GMC Sierra 1500 C3 6.0

Last edited by Green Machine; 12-21-2005 at 10:22 PM.
Green Machine is offline   Reply With Quote
Old 12-21-2005, 10:45 PM   #7
formula_raider
Registered User
 
Join Date: Nov 2005
Location: San Marcos, Tx
Posts: 62
Re: Started new engine for 1st time

Green Machine.....you brought up some good points and I keep running them through my head and it makes me more mad because I was meticulous at putting this engine togeather. The engine was a "NEW" longblock from GM Performance parts about 4yrs ago....it is the "thriftmaster" 350 or replacement 350 that GM sells rated at 210HP. I took the heads off and replaced them with Vortec heads and had some work done to the bowl and valve springs. My head builder said it would be a good idea to shave a VERY tiny slice off the head to make the surface smoother, I agreeed...and it was smoother, better than the new block. I installed the Fel-Pro Rubber Coated Steel Shim gasket #1094 with a compressed thickness of .015. I see these gaskets being used ALL the time in hot rod mags. I used new ARP bolts and I used ARP teflon lube on the threads. I cleaned the head surface with lacquer thinner to make sure it was free of any oils. I torqued the heads in about (4) sequences all the way to 65lbs. I did everything by the book....thats what freaks me out. The ONLY thing I can think of is that maybe my torque wrench may be off....It is old....however the other head is fine. I thought about copper coat, but since it was a rubber coated gasket I decided not too. I will try to take off the valve cover and re-torque; dont know what else to do.
formula_raider is offline   Reply With Quote
Old 12-22-2005, 12:53 AM   #8
Green Machine
Senior Member
 
Green Machine's Avatar
 
Join Date: Jul 2004
Location: Estherville, Iowa
Posts: 3,371
Re: Started new engine for 1st time

Sounds like you are as picky as I am, should be assembled just fine. I would beg or borrow a good torque wrench and re-torque, try at 65 first, then set it to 67 to see if you can get a little more. I've never used new bolts, maybe new ones strecth a little at first ?? And I always tighten the long ones 3-5 more because they stretch more when hot.

Always remember to loosen up your torque wrench when done, as the spring can get weak if you store it tight.

Hope that does it, maybe the finish on the block is a little too aggressive, and a drop or two is getting past there ??, but the rubber sealer should fill most imperfections I would think. I hate to say this, but could it be leaking where you can't see it also?, sorry.
I used to know a tractor mechanic that put Bar's leak in ever motor he did a valve job on to prevent leaks, not saying he was right but I have used it to seal rusty frost plugs before and it works.

There is also that fine silver powder stuff thats supposed to work good too, IIRC there is some GM car with aluminum heads that GM REQUIRES you to put in some sealer, maybe that silver stuff, when you change antifreeze to plug microscopic flaws in the castings.
__________________
1968 C10 307 3spd Long Fleet ------ http://67-72chevytrucks.com/vboard/s...d.php?t=201103
1970 C10 305 Super T10 Long Fleet --- http://67-72chevytrucks.com/vboard/s...d.php?t=202285
1971 C20 383 TH350 Dana Posi ----- http://67-72chevytrucks.com/vboard/s...d.php?t=206894
2001 GMC Sierra 1500 C3 6.0

Last edited by Green Machine; 12-22-2005 at 12:57 AM.
Green Machine is offline   Reply With Quote
Old 12-22-2005, 01:23 AM   #9
Guardrail
And Don't Call Me Shirley
 
Guardrail's Avatar
 
Join Date: Oct 2005
Location: Cameron Park, CA
Posts: 115
Re: Started new engine for 1st time

I had this happen to me on a 307 using that same head gasket. I got pretty worked up about it because I had already sold the car. The new owner was chomping at the bit to come and get it, and I really was dreading tearing it down again. He suggested "letting it ride" and low and behold it sealed itself in less than a day of using the car. I'm still in contact with the new owner and hasn't leaked a drop since that first day. If this leak is very slow, take it out and drive it some. Sometimes things just take a while to take a set....

If that doesn't prove out, don't be afraid of Bar's Leak. You can run it for while then flush it out if you don't want it in there.

Now if it's a BIG leak, it may be time to begin drinking heavily..............
__________________
Rick Tucker
1969 C20/Custom Camper (the Green Machine)Sold
1970 GMC 4000 COE (future Ramp Truck)
1972 K10 Longbed (restoration begins June 2020)
Guardrail is offline   Reply With Quote
Old 12-22-2005, 09:07 AM   #10
68cajun
68 C/10
 
68cajun's Avatar
 
Join Date: Oct 2003
Location: Houma Louisiana
Posts: 367
Re: Started new engine for 1st time

I have used those gaskets twice with the same results you had, leak.
I will not use them again.
__________________
(2009) GMC Sierra Denali 6.2 AWD
(67 C/10 fleetside SWB)
(2018GMC Yukon Denali) Wifes Car
68cajun is offline   Reply With Quote
Old 12-22-2005, 09:45 AM   #11
truckdude239
Senior Member
 
truckdude239's Avatar
 
Join Date: Sep 2005
Location: Lewisville, Nc
Posts: 10,230
Re: Started new engine for 1st time

bars stop leak use it in my other truck one day and it stoped up my thermastat come to find out that was what me leak was the whole time the gasket on my stat house was bad but thats not realted to this thread lol i just will never use it again i flushed my system out and i still have troblue with my stats sticking
__________________
David fuller
Ase Certified Mechanic
Click here to help support our board!!


1971 Chevy c-10 under going a 4.8l LSx swap

Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305

2007 Honda Accord my daily 145kmiles
2002 Honda Accord 4 door With 330k(sisters car)
2005 toyota Avalon 228k( brothers car)
2002 Sububran 5.3 245k
2000 Tahoe 5.3l 378

General manager for Marco's Carwash & lube
truckdude239 is offline   Reply With Quote
Old 12-23-2005, 08:19 AM   #12
LONGHAIR
just can't cover up my redneck
 
Join Date: May 2004
Location: Columbus OH
Posts: 11,414
Re: Started new engine for 1st time

Quote:
I used new ARP bolts and I used ARP teflon lube on the threads.
I would be willing to bet that your leak is past one of the head bolts....and you are lucky if it is only one. I know that every torque wrench and every torque spec sheet will tell you that the torque values are for "lightly lubricated" threads.........but not all of those head bolt holes are blind. The bottom row hits water for sure. I ran into this on my first rebuild in my first car more than 25 years ago. I didn't even get it running before the leaks started IIRC. I just drained the radiator, took the headers and valve covers back off. Then loosened all of the head bolts and coated the bottom ones with some sealer and re-torqued everything. It worked out fine.

Extensions do not affect torque readings. If you put 50 pounds of force at one end.......50 pounds of force comes out the other. That would be like saying that a deep-well socket would be different from a shallow. The only way an extension would lessen the torque is if you twisted it (perminently) Then some of the force you applied would have been wasted in the twist and you would have a ruined extension.
The thing that affects torque is when there is some off-set from the center of the drive, like a crow's foot. These affect the leverage by changing the total length.

The thing that really needs to be stated here (and is a mistake made by many) is that there is no way to "check" the torque that is applied to a bolt with-out loosening it. You have to release and re-apply the torque. It takes more force to move the tightened bolt than is actually applied to it.

Last edited by LONGHAIR; 12-23-2005 at 08:31 AM.
LONGHAIR is offline   Reply With Quote
Old 12-23-2005, 11:18 AM   #13
formula_raider
Registered User
 
Join Date: Nov 2005
Location: San Marcos, Tx
Posts: 62
Re: Started new engine for 1st time

I bought a beam type torque wrench yesterday because my existing torque wrench is a "click" type and probably needs calibrating; at this point I dont have the time to send it off and pay $$ to get it calibrated. I am going to take Green Machine and a few others advice and take off the valve cover and header and loosen up the bolts and re-apply the torque sequence. I did coat every bolt with the ARP teflon sealer, I will recheck when I get them removed.
formula_raider is offline   Reply With Quote
Old 12-23-2005, 11:25 AM   #14
Green Machine
Senior Member
 
Green Machine's Avatar
 
Join Date: Jul 2004
Location: Estherville, Iowa
Posts: 3,371
Re: Started new engine for 1st time

Just to save any swearing, and you probably know this, but drain the antifreeze if your're going to remove any head bolts.
__________________
1968 C10 307 3spd Long Fleet ------ http://67-72chevytrucks.com/vboard/s...d.php?t=201103
1970 C10 305 Super T10 Long Fleet --- http://67-72chevytrucks.com/vboard/s...d.php?t=202285
1971 C20 383 TH350 Dana Posi ----- http://67-72chevytrucks.com/vboard/s...d.php?t=206894
2001 GMC Sierra 1500 C3 6.0
Green Machine is offline   Reply With Quote
Old 12-23-2005, 04:32 PM   #15
glock35ipsc
Next project: 1970 K10
 
glock35ipsc's Avatar
 
Join Date: Feb 2004
Location: Fort Collins, Colo 80524
Posts: 6,685
Re: Started new engine for 1st time

Quote:
Originally Posted by LONGHAIR
I know that every torque wrench and every torque spec sheet will tell you that the torque values are for "lightly lubricated" threads.........but not all of those head bolt holes are blind. The bottom row hits water for sure.
I think Longhair hit it the nail on the head. I have seen this countless time with virgin SBC builders. I use Ultra Blue on each head bolt that hits water. Never had a leak.
__________________
Bob

1970 Chevy K10 LWB "Goldie" 350/TH350 next project!!
1981 Chevy C10 LWB 355/TH350 - My son's truck

LS SWAP FORUM! Tons of LS swap info here!
PLEASE CLICK HERE TO SUPPORT THE GREATEST BOARD ON THE NET!
CLICK HERE FOR THE FAQ INDEX by KRUE
glock35ipsc is offline   Reply With Quote
Old 12-23-2005, 07:28 PM   #16
OJOE
Crew Cut
 
OJOE's Avatar
 
Join Date: Dec 2005
Location: MONTGOMERY,AL
Posts: 757
Re: Started new engine for 1st time

now then you have some good advice but i will give you the bad news. time to go to work and fix the leak. good luck
__________________
85 SWB 1/2 TON CREWCAB/5.3
03 CHEV 3500 DURAMAX CREW CAB
85 CHEV SWB/TPI
06 CHEV TAHOE (WIFES)
30 MODEL A HOT ROD
07 HARLEY DAVIDSON BAGGER
09 STREET GLIDE
AN D A LOT MORE JUNK
OJOE is offline   Reply With Quote
Old 12-23-2005, 07:54 PM   #17
hoser
Account Suspended
 
Join Date: Nov 2005
Location: ILLINOIS
Posts: 145
Re: Started new engine for 1st time

Quote:
Originally Posted by glock35ipsc
I think Longhair hit it the nail on the head. I have seen this countless time with virgin SBC builders. I use Ultra Blue on each head bolt that hits water. Never had a leak.

Ultra Blue = silicone?

Does adding the sealant to the threads affect the torque?
hoser is offline   Reply With Quote
Old 12-23-2005, 09:15 PM   #18
chops333
Registered User
 
Join Date: Aug 2005
Location: mount airy n.c.
Posts: 243
Re: Started new engine for 1st time

every car gm ever sold new has radiator sealant pellets put in the rad. they didnt do just because they did because of new motor coolant leaks
chops333 is offline   Reply With Quote
Old 12-23-2005, 10:20 PM   #19
glock35ipsc
Next project: 1970 K10
 
glock35ipsc's Avatar
 
Join Date: Feb 2004
Location: Fort Collins, Colo 80524
Posts: 6,685
Re: Started new engine for 1st time

Quote:
Originally Posted by hoser
Ultra Blue = silicone?

Does adding the sealant to the threads affect the torque?
I have always torqued them all the same. Never had a problem with one since 1985.
__________________
Bob

1970 Chevy K10 LWB "Goldie" 350/TH350 next project!!
1981 Chevy C10 LWB 355/TH350 - My son's truck

LS SWAP FORUM! Tons of LS swap info here!
PLEASE CLICK HERE TO SUPPORT THE GREATEST BOARD ON THE NET!
CLICK HERE FOR THE FAQ INDEX by KRUE
glock35ipsc is offline   Reply With Quote
Old 12-23-2005, 10:32 PM   #20
hoser
Account Suspended
 
Join Date: Nov 2005
Location: ILLINOIS
Posts: 145
Re: Started new engine for 1st time

Quote:
Originally Posted by glock35ipsc
I have always torqued them all the same. Never had a problem with one since 1985.


Does adding the sealant to the threads affect the torque?

hoser is offline   Reply With Quote
Old 12-23-2005, 11:36 PM   #21
glock35ipsc
Next project: 1970 K10
 
glock35ipsc's Avatar
 
Join Date: Feb 2004
Location: Fort Collins, Colo 80524
Posts: 6,685
Re: Started new engine for 1st time

Quote:
Originally Posted by hoser
Does adding the sealant to the threads affect the torque?

What affect could it have? 65# of pull is 65# of pull, regardless of whether or not the threads have oil, silicone, or anti-seize on them. Like I said, done it every time I've built a SBC or BBC, never had a problem.
__________________
Bob

1970 Chevy K10 LWB "Goldie" 350/TH350 next project!!
1981 Chevy C10 LWB 355/TH350 - My son's truck

LS SWAP FORUM! Tons of LS swap info here!
PLEASE CLICK HERE TO SUPPORT THE GREATEST BOARD ON THE NET!
CLICK HERE FOR THE FAQ INDEX by KRUE
glock35ipsc is offline   Reply With Quote
Old 12-24-2005, 01:00 AM   #22
formula_raider
Registered User
 
Join Date: Nov 2005
Location: San Marcos, Tx
Posts: 62
Re: Started new engine for 1st time

Well, I tore the engine down enough to re-torque the heads. I just broke them all loose then I checked the bottom bolts to make sure that I put sealent on them....I DID. Every single bolt long and short I even put a small dab under the flat washer as ARP says to keep the bolt from grabbing when they make contact. This is the professional ARP teflon sealent made for this...it is rated at 10,000PSI. Anyway...I used my new beam type torque wrench because at this point...that seems to be the only thing that I can think of that failed (my old clicker type torque wrench needing calibration). Re-torqued the head in (3) progressive steps to 65lbs. Put it all back togeather. Started it. Ran for about 10 minutes with no leaks. Then I saw it again after I shut it off for about 5 minutes. AAAAAAHHHH!! It did however seemed to be a much slower leak....I mean it is like a bead of sweat that forms after 5 minutes. At this point...I dont know if my retorqe help it or just running it and letting it cool down for a day has helped. I see no evidence that it is leaking into my combustion chamber (exhaust shows no condensation, no water in the oil.) I guess I will keep a close eye on it and drive it a few miles and see if it seals up. I will probably run a compression test on all the cylinder just to get a base line on the new engine for a comparison at a later date. Im disappointed.....but im still hanging on to hope.
formula_raider is offline   Reply With Quote
Old 12-24-2005, 02:01 AM   #23
glock35ipsc
Next project: 1970 K10
 
glock35ipsc's Avatar
 
Join Date: Feb 2004
Location: Fort Collins, Colo 80524
Posts: 6,685
Re: Started new engine for 1st time

Run it for a couple hundred miles, all the while watching it for signs of progression. Then retorque the heads; that is, check them to be sure they have not loosened up. Don't loosen them and then retighten. Just slowly check them with a good torque wrench to be sure they are on spec..
__________________
Bob

1970 Chevy K10 LWB "Goldie" 350/TH350 next project!!
1981 Chevy C10 LWB 355/TH350 - My son's truck

LS SWAP FORUM! Tons of LS swap info here!
PLEASE CLICK HERE TO SUPPORT THE GREATEST BOARD ON THE NET!
CLICK HERE FOR THE FAQ INDEX by KRUE

Last edited by glock35ipsc; 12-24-2005 at 02:03 AM.
glock35ipsc is offline   Reply With Quote
Old 12-24-2005, 10:20 AM   #24
hoser
Account Suspended
 
Join Date: Nov 2005
Location: ILLINOIS
Posts: 145
Re: Started new engine for 1st time

Quote:
Originally Posted by glock35ipsc
What affect could it have? 65# of pull is 65# of pull, regardless of whether or not the threads have oil, silicone, or anti-seize on them. Like I said, done it every time I've built a SBC or BBC, never had a problem.
Pull?

Its twisting force not pull. I think your confused with the clamping force a torqued bolt produces not a big deal I guess.

Friction form torquing affects final torque.

Thread engagement affects torque each brand of fastener has a different thread engagement thats why I like to use OEM bolts if I am going to use something like ARP then I will be using their torque value.

I remember reading instructions and tech data on Hilti anchors they spell it out in big bold letters NOT to add any kind of lubricant to their bolts when you torque them up including water because it will affect the torque, one job I was on they had a bunch of hilti bolts fail they sent them to their lab and found traces of cutting fluid on the threads, the cutting fluid was coolant used in the band saw used to cut and drill the metal plates that were fasten to the floor, new procedure was to wash the plates with solvent before installing this cured the failure problems, no more over torquing because of the lubricant.

No doubt oil water silicone and other gasket sealers ALL have a DIFFERENT lubricating property how much does this affect torque? This is why I am asking to get a better understanding, it could be the answer to all the distorted bores and pulled threads I have found over the years on home builders projects.

Things go wrong and fail for a reason usually its something in the details like missing your torque or over torque, not following proper torque procedures, when things go wrong its usually some real small detail that caused it and its usually hard to find, open discussion is the path to finding it.

hoser is offline   Reply With Quote
Old 12-24-2005, 12:15 PM   #25
LONGHAIR
just can't cover up my redneck
 
Join Date: May 2004
Location: Columbus OH
Posts: 11,414
Re: Started new engine for 1st time

With-out splitting hairs...I really believe that the point of having something on the threads is to prevent galling. This would give you a false reading that the fastener was tighter than it really is. I think that the most important factor here is that the threads are clean and not totally dry. The holes should have a tap/ or thread cleaning chase run through them and the bolts should be spotless too. Any trace of the old sealer should be gone. I'm sure that the sealer would affect the feel of the bolts as you screw them in by hand..........but as you approach the full torque value, it has to be minimal.
Don't use rusty/pitted old bolts. They will give you falsely high readings, provide less thread contact and contribute to leaks.
LONGHAIR is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:23 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com