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Bearing Nightmare

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UmmYeahOk

UmmYeahOk

Jedi Warrior
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Ok, so I had my crank milled. It took them forever and when I got it back I was told that the rods were now .020 and the main .010. So I order bearings. Well I got a set off ebay and theyre apparently too small. There was some size difference some point in 67. So I order ones for a 68. Of course they were back ordered. Eventually they arrived and appeared to fit. We torqued them down to spec and each and every main bearing cap is now CRACKED!!! When removed, the plastic gauge wasnt even affected. After measuring the mains were fine, and I could have just got normal bearings instead of some fancy milled number.

Someone here might ask why we didnt measure ourselves in the first place... ...well, we're not professionals, they were. Do you question what a doctor prescribes you? No, you just take it, assuming they know what theyre talking about. If you die because they prescribed the wrong thing, is it your fault?

I dont know how much main bearing caps cost, I just Victoria British doesnt sell them. Anyone know someone that does. My husbands emailing Spit Bits right now
 
This might be a problem as the caps are matched to the block and line boring at the factory matches them perfectly. This is why they are not sold separately.
 
You can fix this but as Paul said, the caps are machined as matched assemblies when the engine is first built.

Unfortunately the fix requires that you first find a donor engine and/or a set of unmolested bearing caps. Take your engine all back apart. Take the block and new bearing caps to the machine shop (maybe not the one you used for the crank!) and tell them what happened. They will machine a bit off the new/donor bearing caps and bolt them to the block. The hole for the bearing shells will no longer be round but not to worry. They will line-bore the bearing caps and block at the same time to get everything back to the stock size. It's not cheap but it's doable. It's very similar to what is done when they re-size con rod journals.

I really, really feel for you. I'll inquire with one of my friends to see if he has any caps.
 
something doesn't add up. If the journals were not machined .010 under, and were, in fact, standard size, then putting .010 under bearings in there should have smashed that plastiguage so thin it would have been unreadable. Unless the added thickness was preventing the bearings from ever coming close to seating, and that's also what caused the caps to crack. And Paul is right about the bearing caps. this could get sticky.
 
Banjo said:
If the journals were not machined .010 under, and were, in fact, standard size, then putting .010 under bearings in there <span style="font-weight: bold">should have smashed</span> that plastiguage so thin it would have been unreadable.
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I agree, it sounds like the caps were already damaged before torquing. Was the crank in the engine when it fell over on the stand?
 
No, the crank wasn't in it when the engine went over. The bearings were thick enough that when it was torqued (to 60 ft/lbs) they did this ^ (although not so dramatically) and didn't seat all the way. Since the plasti-gauge was at the top, the bearing didn't press down that far.

Anyone know of a reasonable source for a GT6 block? The only person we know of that has one is the British Parts shop near us that wanted over $1500 for a bonnet because 'the car is so rare'. :frown:
 
UmmYeahOk said:
Someone here might ask why we didnt measure ourselves in the first place...
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I bet you will, next time!
 
Call Scott Harper at Team Triumph. 330-392-7176. www.teamtriumph.com

He is great to work with. He has sort hours but is always willing to answer your questions and has lots of parts.
 
TR3driver said:
UmmYeahOk said:
Someone here might ask why we didnt measure ourselves in the first place...
Click to expand...
I bet you will, next time!
Click to expand...

I SHOULDNT have to. I SHOULD be able to trust the word of a professional.

Wanna know why we do our own work? Because everyone else, the "professionals," lie, make mistakes, then bill me for them. And with things automotive, we're talking this happens 95% of the time. Why do you think we change our own oil? Because only 5% of "professionals" are capable. I HATE having to trust others. But I know sometimes you just have no other choice.

They can't espect their customers to own a digital caliper. If they did, then they wouldn't have told us .010
 
Is a TR6 donor block a possibility here, or are the mains not sized the same?
 
dklawson said:
You can fix this but as Paul said, the caps are machined as matched assemblies when the engine is first built.

They will line-bore the bearing caps and block at the same time to get everything back to the stock size. It's not cheap but it's doable. It's very similar to what is done when they re-size con rod journals.

I really, really feel for you. I'll inquire with one of my friends to see if he has any caps.
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Do you know roughly how expensive that would be?
 
...<span style="font-style: italic">life is good</span>...
 
Called the guy. He was busy and couldn't talk but said he has my number and will call tonight. Sounds like he still has it and has recieved a lot of inquiries on it as he wanted to make sure I was in the DFW area. Should I email him too, or wait for his call?
 
I think the TR6 block is different on its bottom surface and uses a different oil pan. I have no first hand experience with this, I just remember a friend of mine having to modify the crossmember under the engine on his Triumph 2000 when he transplanted a TR6 engine.

Sorry, I don't know the cost of line boring. It was common on very early engines (not Triumph specific). It was also something that was fairly common on performance air cooled VW engines. You don't hear much about it anymore and you would probably have to call around to find out who in your area could even do it. Still, it's a possibility if that engine in Plano isn't available or correct for your needs.
 
UmmYeahOk said:
Should I email him too, or wait for his call?
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Email him a nice note - grab everything and make his life happy and yours too.
 
If it twir I in your predicament; I was email, call, snail mail, drive over, run, send smoke signals or something...

Meanwhile, I'm heading down to the barn to gaze at my GT6 tub, sitting up on saw horses...
 
hilsideser said:
If it twir I in your predicament; I was email, call, snail mail, drive over, run, send smoke signals or something...

Meanwhile, I'm heading down to the barn to gaze at my GT6 tub, sitting up on saw horses...
Click to expand...

I wish I were that close to restoration as you. Mine may look in better shape, but we still have rust repairs before we get it on saw horses
 
UmmYeahOk said:
I SHOULDNT have to. I SHOULD be able to trust the word of a professional.
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OTOH, if you are building your own engine, you SHOULD have the right tools for the job and you SHOULD use them.

BTW, a digital caliper isn't the right tool for the job. But a suitable micrometer can be had for less than the price of the bearings.
 
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