Some Good News Finally!!

Okay!! The one block I took in, had a crack by the distributer drive, so it's a boat anchor!! I took the other one in with the siezed pistons, and it is fine!! It is virgin also!! There is no ridge and we can go stock pistons!! Perfect!! I do have a complete set of 20 overs, but why???? Crank? stock and perfect!! Okay, now this is where I get confused. The machinest said that one crank was cast and the other was steel. Obviously, that means (in american iron talk) forged. Right?? Obviously, we go with the steel crank, but what years were they stock?? I believe it came out of the '69 block!!

Gary....have the machine shop mic the entire length of each cylinder....make sure they've kept their original shape throughout the entire piston throw because I think you're planning on dropping new pistons in there without boring! Remember the last engine that was done half -a$$.....bore it 10-over & put in new 10-over pistons...those sleeves won't be in their original shapes.......Tom B?

Hopefully David Kiehna will chime in here....but remember when he found that his 'B had a Marina engine? He did some research, and wasn't a primary difference a different crank? Maybe the cast crank is a Marina unit...

Two things,Gary. I would think if the piston were frozen in the block it would need to be board. Second, the only crank I have had break was the steel crank. This car belong to a female who was the original owner. It had never been hot rodded. I'm not sure but I think they started using steel cranks in 76.

No Tony!! Of course they will mic the whole thing!! If we bore it will be 20 over, because I have the pistons!! The machine shop that I have doing the work now are awesome!! I have used them on at least 10 engines and i trust them totally!! If they tell me it is fine with stock bore, that is what we will do!! The will balance and everything else!! Do you want to see that piston and rod???

Gary, if you already have the 20 overs, spend the extra change and bore the block so we all can sleep better at nite

REALLY??? Are you saying use the cast???

Chuck, if they tell me it is good, I will stick with stock, but I will test the rings and check end clearances!! It is like Wray said, if Tom says that a mouse (or whatever) can pull a cart, I will hitch it up!! I feel the same way about these guys!! I hope I am right!! I do seriously respect yopur ci=oncern though!! I will run it past them!!! Money is not the issue!!

If Tom's only seen one broken crank out of the zillions he's come across, that probably means either one is just fine! Use the straightest one :-)

I'm saying that I only had one MGB crank break and it was steel. I also saying there is no way I would build a use motor and not boar the cyl.

Bore it 20 over and use you new/old pistions, check the deck on the block and head, re-deck as needed, get new rings and cam, mic the crank and turn or polish it as needed ect. ect.. Don't do if half ass in any way and check the position of that oil hole on the rods.....away from the cam........

Even if the cylinder s hit specs?? If you say not, then I will bore!!

What a guy!! The cam only has 3000 miles on it!! Go ahead, spend my money and I won't be able to build Kim's garage next year!!

At $16 bucks a hole, why not???? You said you have new 20 overs right???

If the pistons were rusted in, there's pretty much no chance the cylinder walls will be perfect - even if the diameter measures in spec. They'll almost certainly have to be bored to clean 'em up...

Heres the thing. There is going to be some cyl wear. Unless this car was totaled driving home from the dealership. Also pistons stick because the rings are corroded to the cyl walls. That usually leaves a ring in the cyl wall.

Well, I would definitely look after it was honed, but if you say it has to be done, it will be!! Like I said, money is not the issue!! Well, within reason!!

Listen guys!! All I said was that the original diagnosis of the machine shop was..........!! They originally told me there was no way that I would get away without a bore job, but when it came out of the hot tank it looked really good!! Now if they hone it and it has a funny thing, they would never let it go!! Neither would I!! Anyway, i am spending the bucks, whatever it takes!! It is not anything about saving $100!! On engines i spend waaaaaaay tooo much!! I just got screwed last time!! Anyway, thanks for the concern!! You guys are alllll great!!

Lemme ask you a question, Gary: If you don't bore it, which pistons are you gonna use? The ones that were stuck to the cylinder walls by their rings? How many sets of those types of pistons do you want...I've got several engines like that & I'll punch the pistons out with a hammer & block of wood & give them to you...FREE!

Oh, what I heard Tom say about cranks was that they don't break but in his experience steel is easier to break....my assumption from that: donot use the steel

Gary, if $$$'s isn't an object, bore the sucker - don't waste time honing - you've already got 4 new 20-over pistons

I wonder why the steel crank breaks easier!! Isn't that weird?? Which pistons do you think I would use??? Oh, and I would not even think of using the rods that I had to hammer on!!! Let's see how the cylinders mic today!! If there is any question whatsoever, it will be bored!! If 20 overs don't work, then I will buy 30 overs!! I just feel that the closer it stays to the way it was designed, the better it is!! There must be a reason that they chose that bore, right?? I am real glad that I asked about the oil holes, 'cuz now I know why they did it!! It isn't backwards at all, it just looks that way to an eye that is untrained in MG tecnology!!

So, Gary, with that philosophy ("I just feel that the closer it stays to the way it was designed, the better it is"), you agree with me that a ZS carb with all emissions operating is the correct way to go on late 18V engines...good, dlad to hear you're all about keeping everything original since that was apparently best!

An interesting article on the MGB vs Marina engine with a paragraph on point re the crankshaft (forged vs cast)
Al

<http://www.motoplay.co.uk/mgcc/sf/990303.htm>

Thank you tony!! As usual, youere so busy patting yourself on the back, you missed the point!! I really don't care what carbs that you run!! If you like a Webber, run it, if you like SU's enjoy!! You like th ZS's?? GOOD!! I was talking about overall engine design and cylinder wall thicknesses!! I can see that you are bound and determined to try and make me look stupid, but I really don't care!! YUP!!! I do feel stupid!! That is why I am asking!! I did think that I had done everything correct, but obviously I didn't!! Enjoy while you can!! What does Steven say?? 'insert knife and twist!!'??? Enjoy!! It won't last forever and I can deal with it!!

I read it and it looks like the cast crank is the cheap one!! What's up with that!! Tom said the only one he saw broken was the steel one!!! The article is exactly what I thought would be the case!! I trust Tom TOTALLY, so now I am confused!! I was leaning toward the steel crank, but last night Tom gave me reservations!! Thanks again!!

I think Tom said they are all good Gary. it happens that out of the hundreds of cranks he has dealt with the only ONE to break happened to be the forged crank. I'd have them both checked for straightness and journal size and use the one in the best state

No, Gary....what I was trying to get you to understand is that is been 20+ years since that engine was produced....there have been several technological advances since then...&, lots of ways to improe on the original design....boring 20-over is part of the normal maturity of a block...it doesn't affect anything....think about NASCAR & other racing forums...they prefer 'seasoned' blocks...that means, they've been used & proven & probably are bored..........
..the carb example was just to show that any improvements are okay!

I think we have a little terminology problem here about crankshafts.
forged, cast, etc.
Per Peter Burgess "How to Power Tune MGB 4 Cylinder Engines":
"The best cast crank is the flat sided one to be found in 18V engines from 1971-74."
Engines earlier than 71 had a "steel crankshaft" (P. Burgess words).
If I've got this right, pre-18V engines had a "steel crankshaft". After 71 all engines got a cast crank. Burgess prefers the cast crank with the flat, rectangular counterweights as opposed to the later rounded, lobed crankshafts.
How does this jive with your experience Tom?

Gary - do you have P. Burgess's book? If not, I highly recommend it.
pg. 35 discusses Rocker arms & shaft.
Just reading it brings several questions up;
1. Are you using the steel or the aluminum rocker posts?
2. Are the rocker arm pads centered on it's respective valve tip?

Burgess says that you can adjust the pushrod length to accomodate any head skimming. Adjust the pushrods at the round pads on the bottom (lifter end).

Refresh my memory here. What engine model are we dealing with? I've forgotten.

Thanks David!! Cast rocker posts, and a '66 engine!! My real question why does it matter if, as I was told by somebody, that all parts are interchangable?? Dumb question?? If it is sorry, I am trying to figger this thing out!! Tom said that the newer style lifters and older style rockers weren't interchangeable, so that may be my problem with the adjusment screws. Anyway, if they are not, simple!! I just e-mailed a guy that Wray reccommended, and he just sent me an article of about 30 pages!! I just printed it and will read asap!!

Going back to the bible here (Burgess), he says that the non-18v lifter/pushrods can be swapped with the 18v lifter/pushrods as a set BUT
a BIG BUT - "the valve train geometry will need careful checking."
Sounds like Tom B. and Burgess are in agreement.
Morale of the story here is that if you do swap the non-18v lifter/pushrods to the 18vs, you've got to put in the pre-75 18v rockers.

See, Tom is always right!! Tom said that I could plane the pedistals and accomplish the same thing!! I trust Tom!! I am leaning towards that, because I do not have a newer rocker assembly!!

You know Gary I would think that the steel crank would be the best. I have cast cranls in both my cars, and they both have seen in excess of 7k many times. I do like the cast B crank because it is some lighter. I really don't know what I would do in your case. My partner was just as puzzled as I was to see a 5 main B crank break. Let alone a steel one. Also what made it more misterious was knowing the car and owner. We had been maintaining that car for over 15 yeras and knew the owner was not a female that would ring it out.

Jeez, Gary! I've told you all along you can use either set of lifter/pushrods in the correct combination & that there's no reason to deck the pedestals but you keep coming back to that...David's told you thst, DW's told you that......has anyone else on the BBS jumped in to agree with decking them? NO! Are you listening to us - we're all saying the same thing - you keep going back to your original position!

Here's the deal: nobody beat on that rod with a hammer...they were put in backwards in an unmatched set, one of them (the unmatched one) allowed too much heat to build up in the bottom of the cylinder...the wrist pin separated & the rod beat itself to death...you probably also have some problems with your pushrod/lifter combination or how they fit together...forget the head, its not the problem...forget vthe pedestals. they're not the problem....&, parts is parts so long as they're used in proper combinations or as matched sets....whatever/whoever did whatever incorrectly to your short block is your problem!

I guess I'm the only one not trying to be tactful (but I'm trying to help): buy the book, follow it when you build the next engine, use new pistons bored 20-over, balance everything & put it together at least twice like David says!

Damn Tony!! Do you want to see the rod?? The wrist pin didn't and could'nt come near the marks!! The machine shop agrees!! Somebody tried to straighten it!! I have offered 3 times to send it to you and you have never even acknowledged it!! Tom said that I could deck the pedistals, but he said he didn't know why I would when I could just get a new rocker assembly and braze up the hole and grind it off level!! The reason?? Because I have them, and know what it needs and the machine shop said they can do it easily!! I have a spare set of this style if it doesn't work!! Anyway, I have been chatting with Wrays friend Steve and we will see what he says!! I printed out about 20 or 30 pages that he already sent me!! if I deck them, and it doesn't work, what have I lost?? I will know right away!!

Gary...I'm not saying the rod beat itself up on the wrist pin..I agree with you that there's no way that could've happened...however, the piston was moving around as the rod slammed itself into the bottom of it...&, the bottom of the block at the cylinder opening was just sitting there as the rod slammed itself into it...hang onto the rod, you may need it in litigation...we'll look at it over beers next summer in Victoria! (if you have a digital camera, snap a photo)

You miss the point buddy!! The wrist pin was totally intact!! It never moved in the piston!! Just a little end came off the c-clip and ran back and forth thru the wrist pin before it came out thru the rings and killed half the misquitoes in Boise!! :o) Trust me!! I will try and take a picture!!

Now, so we are clear on what I said. I had this situation with the valve ajustment screw once. It was an early engine that I converted to later push rods, and tappets. Out of frustration I swapped the early rocker assm out with the later one and it solved the problem. I have measured the rocker towers on the two different types. The only difference I found was the distance from the center of the rocker shaft to the base of the tower was less on the later tower. I have done other conversions and not had the problem.

Yes Tom!! I did understand that, and I really appreciate your help!! I will get it sorted out!! At least now I know what the problem is, but some people just are having a hard time with it!! Later rocker assembly or mill the pedistals, right??

Well, I was at the machine shop today and we decided that we will use whichever is the best!! I will send you an article concerning MG engines!! If you don't mind, let me know what you think!! Some things the guy says go against what the Haynes Manual says!! Coming at you!! :o)

Haynes manual? Your shop is using that piece of crap! Do you know how Haynes manuals are produced? Haynes taoesk cars apart their way & tells you that was the way to do it...then, they put hemt back together & tell you that was the way to do it...&, they do it for every car out there....Haynes are good for toilet paper only - no, they're not even good for that, paper's too thick....

...go get a Bentley & give it to that shop so this engine will at least have some sembalance to what Abingdon designed!

Ooops, "semblance"........though 'sembalance' does seem appropriate in this instance!

Now Tony, the Haynes isn't all that bad. Sure, the Bentley is great for specs and such, but lacks pictures, which for some people is a big help. Yes, the Bentley is tops when it comes to engine mechanics, but if you're wanting to know how to remove a windshield wiper motor, or brake caliper (I'm just using examples) then it's great to see a picture and be able to read what they're talking about.

For anyone who's not mechanically minded, but has an MG, I always recommend the Haynes. Chances are they won't be tackling major engine or transmission repair, but they should know how to do minor stuff. Heck, I like the Haynes over the other brand as well (I can't remember it, but it's the ones at all the Autozone's, Pep Boys).

It's like AOL and the internet: Anyone who's not computer/internet savvy, I recommend AOL. Mail is relatively easy to get to, they have built in popup stoppers, virus scanners, etc etc. You can get all this stuff but it's not in a packaged deal. It's like a giant mall. You don't have to look far for something you might need. But everyone knows the best products/deals are at a little hole in the wall off the beaten path.

Hey, I'l admit it: I'm a computer dummy!I like AOL because everything is handy & neatly packaged...but, lots of times I just close it off & use Internet Explorer

...but, a shop using Haynes? Are they a "mechanically challenged" shop?

You're right on the money there, Tony. I totally agree a shop should use something a bit better than the Haynes.

I still use AOL for e-mail only. I've had it for about 12 years. We're on cable now, so it only costs us $7 or $9/month (under the BYOP-bring your own provider plan).

You're smart to clost out AOL and use IE. Even though you dial into their system, it's slow going through their browser (or at least it used to be before I got cable).

NO!! I used it and have used it lots of rimes with lots of engines!! Anything that was wrong was set straight thru the Haynes manual!! I have only had one engine assembled at a machine shop in my life! It was a disaster!! Okay!! I know I have had a disaster this time, but I will fix it!! I don't reall care anymore how much time or how much money!! It will be good!! Anyway Tony, I have sure gleaned a lot of information from everybody on here and the web!! I have even learned a lot from you, even though sometimes your reply gets my hackles up, but i just put that don to the fact that you guys sure must have a different way to replying to a simple question down there!! Thanks though!!

Take the ball and run big guy!! BUT first get the facts right!! Why do you assume everything in it's dumbest degree?? I don't get it!! What shop uses the Haynes?? Certainly no shop I know!! Maybe in Alabama, but not here!! What a guy!!!