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.

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.

Re: Started new engine for 1st time
 

I would pop the valve cover and torque the head down, before I yank the head.

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.

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??

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

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.

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.

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..............

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.

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

Re: Started new engine for 1st time
 

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.

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.

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.

Re: Started new engine for 1st time
 

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.

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

Re: Started new engine for 1st time
 

Ultra Blue = silicone?

Does adding the sealant to the threads affect the torque?

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