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planet6racing
04-07-2004, 08:14 PM
OK, so I put my engine all together and torqued everything properly.
Monday I started the engine and brought it up to temperature. Noticed an
oil leak, so I shut the car down and fixed that yesterday (new sensors for
autometer gauges needed to be even tighter). Today, restarted the car and
brought it up to temperature. After a couple high RPM revs (5500 RPM),
walked around the car to check for oil, but saw water on the ground. Upon
further inspection, water is coming from the front right side of the
engine (when facing it from the front) at the head gasket joint.

The head and block were decked flat and I'm 99.9999999% certain I torqued
and yielded all bolts per the specification. My first inkling is to pop
the valve cover and add another 10 degrees to the bolt on that side, but
I'm not so sure that is a good idea. The other option is painful: pull
the head and start over. It is mostly painful because it would require
removal of the front cover and dropping the timing chain.

Anyone have any suggestions?

------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

gsbaker
04-07-2004, 10:24 PM
Bill,

I agree. If everything is flat and the gasket is good, something must be loose.

It sounds like you are using torque+angle so adding 10 degrees can't cause any real damage even if it is the wrong approach. If that doesn't work I'd try loosening and re-tightening the head.

Gregg

planet6racing
04-07-2004, 11:33 PM
Yeah, thinking about it, I'm going to get the good torque wrench from work (NIST Traceable) and torque everything again.

Thanks, Gregg.


------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

joeg
04-08-2004, 08:11 AM
What kind of car? I'm not convinced its the head gasket... yet

planet6racing
04-08-2004, 09:32 AM
Geez, Joe. You've been on this board for a while, you'd think you would know what I drive!!! http://Forum.ImprovedTouring.com/it/smile.gif

It's a 92 Saturn. The head bolts are torque-to-yield, so it is possible that one of the bolts isn't properly torqued/yielded. As many have pointed out to me, the Craftsmen torque wrenches can be off, thereby resulting in a lower starting torque and therefore never truly getting the bolt to the proper tension.

The easiest thing to do (short of selling the car) is to pop the valve cover and re-do the entire tightening procedure with a real torque wrench. If it continues to leak after that, well, then I'll have some thinking to do.


------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

Tom Donnelly
04-08-2004, 10:31 AM
Bill,

On some cars its a good idea to re-torque the head after one run at operating temperature. I don't know if this applies to saturns or not. It was absolutely manditory on my old mgb and triumph.

Tom

badal
04-08-2004, 11:28 AM
Any chance the head bolts are bottoming out in the holes before they clamp the head?

------------------
"Bad" Al Bell
ITC #3 Datsun 510
DC Region MARRS Series

joeg
04-08-2004, 12:12 PM
Good Point, Al. Maybe the new washers have less height.

I assume that the replacement gasket came with new bolts and washers.

If it is decided to un-torque and re-torque, then you should not be reusing the fasteners.

Those "torque-to-yield" puppies came stock on my car, but I have never built or re-built a motor with them. I switched over to allen head cap screws of the same length or ARP studs.

planet6racing
04-08-2004, 12:33 PM
The bolts were brand new. I thought about the ARP stud route, but decided against it for some reason.

I'll check the bolt length. With the head and block both shaved, it is possible that the bolts may be too long.

I just hope it is all this easy. A bad head gasket might make me blow a gasket...

------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

ITSRX7
04-08-2004, 01:10 PM
I was thinking also that if the head and block shaving wasn't perfect, you would have an issue as well.

AB

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Andy Bettencourt
06 ITS RX-7
FlatOut Motorsports
New England Region
www.flatout-motorsports.com (http://www.flatout-motorsports.com)

whenry
04-10-2004, 10:30 PM
When you originally torqued the head, did you apply the full torque value or step the torque? My guess is that the head is not properly torqued, followed closely by the wrong length of head bolt. It would seem to be a major screw-up for the head/block surface not to be correct. Ain't racing fun? YMMV
the good news is that you really cant screw it up any worse at this time except to warp the head by running the motor too much. Go ahead and try all the possible solutions in problem solving but be prepared that you are going to have to remove the head and confirm everything from the beginning of the install.

planet6racing
04-10-2004, 10:55 PM
Well, thanks for the help, all. But, the bad news is the head must come off.

The bolts are the right length. The torque was stepped as per the FSM. I even loosened them and went through the whole procedure again. Oh well, first race isn't until June so there is some time (although I'm still plenty pissed!).

But, the other question I have: The transmission is rotating when the car isn't in gear (i.e. the rotors are spinning but the car isn't in gear). I just rebuilt it and everything looked fine and I put in a new-to-me torsen. The spinning can be stopped by hand, but it seems a little odd...

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Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

Greg Gauper
04-11-2004, 01:06 AM
If you mean the car is up on jack stands and the tranny is in neutral and the engine is running and the front wheels turn but can be stopped by hand.....

I think this is caused by the cold tranny oil providing just enough friction and drag to cause the gears to spin. My Honda does this also.

lateapex911
04-11-2004, 01:21 AM
Bummer Bill-

I have only rebuilt the "odd ducks" of this world, my rotary, and my 911, so my head experiece goes back to my college V8 days...worthless.

But, after working on the 911 with my buddy the ME, I have an appreciation of a good tq wrench. Gotta get me a new one actually. Might be a good thread topic.

Now I know that Saturns and Mazdas are 3 planets apart, but my RX-7 does the same thing in neutral.

I think your worries are up top.

Lets hope its just a gasket!

------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

[This message has been edited by lateapex911 (edited April 11, 2004).]

planet6racing
04-18-2004, 10:54 PM
Well, just wanted to thank everyone for their advice and support.

The engine is once again back together. New head gasket, new bolts, and some sanding of the grinding waves in that area have solved the problems. Now I just have an oil pan leak! http://Forum.ImprovedTouring.com/it/smile.gif

As for the trans, one long engine run up through the full RPM range seems to have taken care of the problem.

Thanks again! I guess I can take the For Sale sign down now... http://Forum.ImprovedTouring.com/it/wink.gif

------------------
Bill
Planet 6 Racing
bill (at) planet6racing (dot) com

gsbaker
04-19-2004, 07:14 AM
And the crowd goes wild!

All Hail Bill!

http://Forum.ImprovedTouring.com/it/smile.gif http://Forum.ImprovedTouring.com/it/smile.gif

Gregg

Team Rocket
04-23-2004, 07:05 PM
Just a comment on this thread: Generally, torque to yield bolts should not be re-used unless it specifically says so in your manual. There are some bolts where you "stretch" the bolt to get a more precise load - some rod bolts come to mind. In fact, measuring the length of a fastener before and after load is applied is a great way assure that you have consistent loading or clamping load. Another way to do it is by applying a torque, then going an additional number of turns (or additional angle) which streches the fastener. This can also be very consistent because of thread pitch. But if you torque a fastening device to its yeilding point, then it may not return to its original length when you release the load. So then you re-install it and stretch it again. And again...

What is not done enough in automobile manuals is defining the lubricant to use under the head of the fastener to assure a constant load vs torque relationship. But perhaps the margin of error in torque values is so large in these uses that it's not that important.

Jim