MG MGB and MGB GT Tech Talk
The $#@^&!!!!! rod looks bent!!! It looks twisted and bent, and the funny thing is that the first time the shop insalled it backwards, and I turned it around!! The clip busted on opposite sides!!! Bad rod, right??? What a piss off!!!
That explains the bronze in the oil. I imagine that with a bend, the rist pin would be pushing into the one keeper until it popped.
Glad you found it, sorry it was so spendy to get an answer.
Us canaadians have nothing but money!!! :o) Not really!!!!
You have some left? Come on back! :)
I wish we had remembered to do the listening test with the screwdriver, but things started moving in a different focus with the oil cap.
So how is the block?
Screwed!!! I need a new block!! I could sleeve it, but I don't think so!!
I thought you had a block up there. I'll check to see what is under the bench tonight when I get home.
I wonder if the rod installed the wrong way caused the twist/bend? In any case it must be a relief to find the cause of your woes, even though it cost two blocks to do it! Good luck with the rebuild.
I'm still not convinced the rod was bad...same hole, different rod? yet, same problem?....
Gary: is it your original crankshaft to which both rods were connected? I need to know to follow through on a theory I have......is it the same crankshaft that was connected to both rods?
It was same rod same crank!! Will be different rods and different crank!! Where do I get those teflon plugs?? I do have a block, but it is pretty rusty!! I am soaking it to get the pistons out now!! A 12 lb sledge should do it!!
If it was a bad crank, it would show in bearing wear, and it doesn't! But, I will not take a chance!!
Not necessarily would it show in bearing wear if the rod cap was properly torqued...look the crank journal over real closely....
1) did they inadvertantly widen the journal ever so much so that the rod was sitting flush on the crank but operating at an angle in the cylinder?
2) how are your thrush washers?
3) were thrust washers the correct size (yes, they come in different sizes)?
4) do thrust washers show any wear marks?
5) Is it possible that the rod in question was from a different engine & required a different size thrust washer than the other rods?
...or, it could be a rod with a slight bend in it that wasn't noticeable when you built it....when you go back with your new engine, check the rods end to end (& balance them)...&, pay the $$$'s to have all reciprocating parts balanced to one another by a competent machine shop (&, I mean ALL reciprocating parts - harmonic balancer to flywheel !!!)
Tony, I did pay to get it balanced!!! It was a wrong choice in machine shops!! I asked the local British car shop who they used, and they gave me it's name!! I will definitely go back to my original shop!! I would say that if I can see a bend and a tweak, that it is a screwed rod, but I will let the experts with equipment for that tell me!! I will not under any circumstances use that rod, an unmatched set of rods or that crank!!
Not trying to piss you off, Gary....just trying to get to the source of the problem.....
You couldn't piss me off!! :o) I appreciate the help!! I have the rod in my truck, will get it checked today!! I will bring home my compressor tonite to finish stripping the block!! Thanks again to everybody for the support and help!!
Gary...when I said: "pay the $$$'s to have all reciprocating parts balanced to one another by a competent machine shop (&, I mean ALL reciprocating parts - harmonic balancer to flywheel !!!)".....I meant DYNAMIC BALANCE them!!!!
...&, don't forget to take a set of rings & bearings to the machine shop so they can incorporate them into the balancing of the rods & pistons....you probably know all that, but it does't hurt to go over it again in light of things that have happened (for other bbs-er's edification)
Tell me if I got this right....
Outbound trip - clip came loose and the resulting banging around twisted the rod.
Return trip - twisted rod caused rings to go bad in it's cylinder
Or was the rod twisted at the start of the outbound trip?
Neat mystery here. What's the next chapter?
After reading Gary's saga, I've added another step to my rebuild procedure: put a straight edge on the rods.
A while back, I had a bad set of problems with my B's engine that were all sorted out finally. I'm giving the crown of bad luck back to Gary, he's earned it....
Set a short piece of 2X4 or 4X4 on the piston and slam it with that sledge, she'll break loose. Then just keep working it back and forth with a wrench on the damper bolt. I've never seen a bent rod cause a problem like you had, but there's a first time for everything. Since it was bad enough you can see it and it didn't go ahead and break, maybe so. Your crank is probably OK. They can set it up in the crank grinder and put the dial indicators on it and tell pretty easy. Man, I'm glad I had my rods reconditioned when I did my engine.
That is what I did Tony, I never build an engine without it!!! Thanks though!!! I seriously do appreciate all the help!!! And Yes, the rod was bent, and the funny thing is that it threw the clip on the same side both times!! I think that the machine shop should have picked it up the first time!! I know why we didn't in Boise, but that is totally different!! I am just going to run another block down to the shop right now!! It has never been bored and the crank is 10 over on both and looks perfect to my eye!! I'll keep my fingers crossed!! :o)
The rod was twisted, that is what caused all the problems!! A decent machine shop would never have let it thru!! Oh well, live and learn!!
Ask your machinist to make you up some. Take him a piston. I still bet it was the rod.
It was the rod!!! No doubt in my mind!! It is tweeked and it showed at the machine shop!!!!
Gary: Sorry to hear of all your troubles. Hope all turns out well. Feel like I should be knocking on wood, or something, as I dropped of my bottom end for rebuild this week. Tony, thanks for the advice re dynamic balancing. Do other posters agree that it should be done?
Bill - re dynamic balancing:
Do it. The cost is merely incremental. The avoided cost is high. The insurance premium is low. Engine life and performance is enhanced.
Gary, check your bill on the first job and see if they have anything about reconditioning the rods on it. If so, you may have gotten a free ride all the way to Wyoming and back.
Wouldn't that be something, but unfortunately it was about 7 years ago!! Next restoration, engine last!!!! :o)
Absolutely!!! Always balance!! Everytime I don't, I get bit in the ass!! Unfortunately, I thought I was still balanced in Boise!! Anyway, lets get Loma on the 'good repair guy' list!!!!
Gary, I've followed your adventures with great interest. I'm glad you and Alida, and your car are back home. I'll bet you some home pickled cucumbers that this rebuild will be bombproof. When you going to post a picture of your Hard Luck Trophy?
They didn't give me a trophy!! Everybody just laughed at me!! Maybe it was the Canadian accent!!! :o)
That bronze in the oil kept working the mind. Didn't make sense if it was a guuide.
I don't do it the way others do. I don't have problems. Still, it is not a bad thing, and if you are going racing, should be done.
