I was thinking!! (strange??)

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Apr 03, 2003 19:44:33
Gary Lloyd

Tony has been a firm believer in not tightening in the studs, in fact, I believe he said to back them out a turn. OK, I see his point, but then I read this from University Motors, isnt that John Twist, the MG guru?? Also, Tom says he tightens them in all the way, like I did!!

Re: engine cooling leakage
Author: Eric Welty (---.mis.prserv.net)
Date: 04-02-03 07:02

I had the same problem on my rebuilt engine, and posted it here on this BBS, and was reminded of something that I saw whilst surfing all things MG but chose to ignore. Hey, if I didn't do everything twice, what would I do with my spare time?
Anyway, I redid the head as per below (from University Motors, I think), and have run it for 15 minutes or so, so far so good!

MGB WEEPING CYLINDER HEAD: The rule is, all rebuilt B series engines weep between the block and head, between the 2nd and 3rd spark plug. Some actually piss. To remedy this problem: That center exposed head stud, RH side, between #2 and #3 is the guide stud -- the hole in the head is 3/8 whereas the other holes are 7/16. Clean out the stud hole in the head with a 3/8 drill. Polish that stud, at least. Ensure a chamfer at the threaded hole in the block. Chase the threads on the stud, nut, and block (3/8-18 and 3/8-24). Ensure the head is planed to 0.001." Ensure that the top of the block is cleaned to a SMOOTH finish. Fit the studs back into the block with only about 5 lb-ft torque. Place a THIN film of clear silicone, RTV, sealant on the RH side of the head gasket. Into that EXTREMELY THIN film, place two strands of stranded, flexible wire about six inches long, twisted together, along the outboard side of the gasket, between its edge and the water jacket holes so that the thickness of the head gasket is effectively increased by several thousandths. Goodbye leaks.

Now I think he tightens them in more than I did!! I just put them in finger tight, but snug!! Any ideas?? I underestand that Tony has had great success his way!! I was just wondering what is the correct way?? Also, I have over a 1000 miles on my engine, retorqued them once (hot). Should I be retorquing again?? I used a stupid copper gasket!! I didn't know that I could get a very forgivin Felpro at that point!! I had not dicovered this site yet, nor could i use a computer!!

Apr 03, 2003 20:07:53
John D. Weimer

Man, I don't know. I put the studs in only snug, used a Fel-Pro head gasket, torqued it once, but 5 ft lb over spec, took off, and haven't had a problem in 9 years. I did clean and straightedge the top of the block and none of the stud oles were raised, so I didn't chamfer them.

Same like you, no computer, no BBS. Unlike you, I had never messed with an MG before and didn't even know anybody who had. It was Bently manual and intuition all the way.





Apr 03, 2003 20:09:12
tony barnhill

If Eric Welty had done it my way, he wouldn't have had to put a ROPE between his head gasket & head! And, if he'd used my method he wouldn't have had to use RTV SEALANT....hell, that's another example of a DFPO putting a bandaid on a problem without solving the problem!

Here's what John really says about torquing down an MGB head: "I wire wheel and oil the studs before fitting them. I run them, oiled, into the block to about 5 lb-ft, and then torque the head in an ascending pattern of 10 - 20 - 30 - 40 - and finally 50 lb-ft on the MGB."

....if you do it like John describes, its the same as my method of taking them all way down & then backing off a bit...5 lb-ft doesn't even seat the bolts in their holes & allows them to snug down as you're increasing the torque!

Sticking a rope between the head & gasket!! Hell, I bet he also uses STP to increase compression! &, fills his tranny with sawdust to quieten it....

...Gary, you really should get on John's mailing list so you get his weekly updates!!

Apr 03, 2003 20:15:32
David Maples

5 lb-ft torque, finger tight, backed out a turn
I think all of those are just a different shade of the same meaning.
Which is: you want the torque to be spread between the top threads and the bottom threads. There isn't any way I know of to make sure the torque is EVENLY distributed. You pays your money, you takes your chances.
.... then you pays your money again....... sometimes.

A suggestion about the advice of Mr. MG guru Twist:
"all rebuilt B series engines weep between the block and head"
That advice might have been given for earlier years. Namely, before the fly-cutting head deckers were commonly available at most machine shops. Maybe I've been lucky, but neither of my heads have leaked. Used fly-cutters on both of them (also decked the blocks). Both of the heads were 18Vs (early 70s). Maybe Mr. Twist's advice is more applicable to the 60's heads.

Apr 03, 2003 20:15:50
Steve F

Actually, that's not Eric's suggestion, that is from John Twist. It's on several MG web sites.

Apr 03, 2003 20:22:08
Gary Lloyd

Hey, like I said, I tightened mine in all the way, used a copper gasket and it doesn't leak!! Actually 5 lbs is 'snug'!! Did you think I was saying you were wrong?? Chill out man!! Now, how do you get John Twists weekly letters?? Sometimes you make me laugh!! Also, should I retorque again?? If so, hot or cold??

Apr 03, 2003 20:30:21
David Maples

I'm curious about the hot or cold retorque myself. I've seen it recommended both ways. What's up with that?

Apr 03, 2003 20:36:57
John D. Weimer

I don't know about any of this silly crap. I know what the old man who taught me the trade told me to do, I do it, have always done it , and it has always worked. To give you some idea of how many times I did it; in one three week stretch I remember doing 3 short blocks and 5 valve jobs. Three of these wret V-8s so that makes 8 heads. These weren't send the heads out jobs, I did three angle seats and the whole bit on every valve job I ever did. I have no idea of how many heads I've had off and on and never, I mean NEVER had a problem with one. Sometimes I think people create their own problem just by trying to do every damn thing they see in a book on a single job.

Apr 03, 2003 20:41:47
Tom Bedenbaugh

I have built too many British engine to count. From MG's to Jags. I always snug the studs into the block using a Snap On stud puller. Never used a toqure wrench to do it, but I figure it would be about 5 ftlbs. I never put anything on the head gasket, and I have never had a head weep or ever leak. I do have every head decked, and every block check for flat surface. As for retorquing. I retorque after first start up, at 100 miles and lastly at 1000 miles. On cast iron heads I toqure hot. On aluminum stone cold.

Apr 03, 2003 20:45:44
John D. Weimer

I've never re-torqued a head. I don't think it's necessary if you use a good gasket to start with and I know I'm going to catch hell nine ways from Sunday for saying so. Screw it, if anybody thinks they are going to influence, impress, or change me on this subject they're wrong again. I've enjoyed nearly 40 years of total success with my methods in this area and I'm not changing one thing.

Apr 03, 2003 20:46:13
Gary Lloyd

GOOD!! Thanks Tom!! That is what I will do!! How many lbs torque?? Time to retorque tomorrow night!!

Apr 03, 2003 20:46:51
Tom Bedenbaugh

I have seen people make a job more difficult than it is many times. There is now way I would fool with that silly wire trick. I had a bunch or people tell me I needed to put copper wire around the combustion chamber on the Midget engine because I would blow a head gasket at 235lbs of compression if I didn't. Well, it's been 7 years now and I'm still waiting for it to blow.

Apr 03, 2003 20:47:01
Gary Lloyd

With copper gaskets John??

Apr 03, 2003 20:50:29
chris roop

Same as for knowledge. I cranked them in, used a Fel-Pro, and no trouble. I currently have two cars that have had weeps. One was cured by retorqueing the head, the other, we'll see what develops. It's hard to figure what someone else may have done before you got there.

Apr 03, 2003 20:50:44
Tom Bedenbaugh

Heres my thought on it. How much trouble is it , and it's cheap insurance. I know there are head gaskets that don't need to be retoqure, but the last thing I want to do is have to pull a customers head to replace the head gasket free of charge. Let alone the bad word of mouth that will follow.

Apr 03, 2003 20:56:14
chris roop

But I bet you opened your shop manual, turned thrice counterclockwise, held it above your head and said "May I be blessed in this endeavor!".
That's the trick. Works every time for me. :)

Apr 03, 2003 20:56:26
Gary Lloyd

So, what should I retorque it to??

Apr 03, 2003 20:59:25
David Maples

Do 50 Gary.

Apr 03, 2003 20:59:55
chris roop

?The reason has to do with metal expansion. Torque hot, all is expanded and when it cools, it goes tighter. If you tried to torque tighter than the recommendation when cold, the metal would snap. It is more elastic when hot.

Apr 03, 2003 21:00:55
David Maples

Incrementally.

& don't forget to open the shop manual, do the chant, etc.

Apr 03, 2003 21:03:53
chris roop

Check your book. JDW is probably right, but like Tom, I am a belt and braces guy. Unlike Tom, I sometimes read the numbers wrong I guess. And it is nice to get a fix before blowing stuff.

Apr 03, 2003 21:08:24
John D. Weimer

No, never a solid copper gasket. Some of the old flathead engines had copper with asbestos sandwiched between, but they had three times the head bolt or studs as found on most OHV engtines. They would wear a good man out torquing their heads, espcially a straight eight flathead Pontiac. I always cleaned the bolt holes in the block, the threads on the bolts, oiled the bolt threads, and under the bolt heads. Any time I had the head studs out of one they got the same treatment, no torque check, just snugged to the bottom with a pair of pliers to be sure they were bottomed out. Head torquing was always done in sequence and in three torque steps until tightened to spec, but then once more to 5 ft lb over spec after it had sat 30 minutes or more while I did something else on that job. It ends up about the same as retorquing by giving the gasket a little time to settle in, but after you crank the engine up you're done and don't have to do that again.

The Jettup will be a different story. It has torque to yeald head bolts. First step id 45 ft lb, next turn them down another 90 degrees then run the engine up to operating temp, let it cool and turn them down another 45 degrees. In that last step you have to be sure you make the full 45 without stopping. A lot of engines are torque to yeald now but this is my first one.

Apr 03, 2003 21:31:32
Gary Lloyd

Sorry David!! I don't chant!! :o)

Apr 04, 2003 07:50:47
Dave Livingston

Isn't that something like "I've got this neat solution, now I have to go out and find a problem that it fits?"

Apr 04, 2003 12:13:46
John Castle

If the book slips off your head whilst performing this ritual, is it a bad omen?

Apr 04, 2003 19:24:08
Gary Lloyd

You guys are weird!! Where is Tony??? I just asked a question!!

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