TheSamba.com :: View topic

Fri Mar 03, 2023 11:37 am

Yeah.....I hadn't read about machined bore errors much in the ten years I've enjoyed pouring over this site.

Sad reality is that is cheaper to buy bearings then purchase accurate tools needed to do measurements. Unless I'm being a tool snob and I can find good values.

Buddy that measured previously is over 2 hours away each direction.

Got Mahle bearings on the way.

Fri Mar 03, 2023 9:39 pm

When my murdercyle engine went together.....I also had to get several silver line sets to get them all to the right size.

Sat Mar 04, 2023 7:47 am

If you have a 0-1" mic buy a ball attachment for it (Amazon $20) and you can measure the wall thickness of the bearing to see if they are the problem.

Wed Mar 08, 2023 8:22 am

new Mahle main bearings on #4 and #1......still binds.

Don't know what else to do except send crank, bearings, with case to the machinist. Great....... more time mo money.

Wed Mar 08, 2023 8:55 am

The only solution is to measure, and find a solution.

There are bore gages and micrometers on Amazon pretty cheap. If I was and engine builder by trade, I'd spring for better ones, but the cheap Chinese ones seem to be decent. I doubt I could get better measurements with the expensive stuff. A $1,000 set of golf clubs does not make a hack like me PGA material.

Wed Mar 08, 2023 9:14 am

yeah without KNOWING more about measuring tools it's hard to KNOW the "Value" of diff manufacturers.

Been recommended 'GoodSon' tools. Never heard of them but maybe just maybe they will stand behind their products. No terribly expensive.

Is there is a way to measure that the bores are aligned correctly?

Wed Mar 08, 2023 11:38 am

Wed Mar 08, 2023 11:40 am

thanks.....

Wed Mar 08, 2023 12:00 pm

Couple questions. Your problem is the #4 bearing, near the crank pulley? Is the pulley installed? Can you put it together without the #4 bearing, no pulley and ALL the nuts fully torqued? Need to isolate better

Need to measure case bore, fulley torqued, measure bearing od for crush and measure oil clearance with bearing in case, fully torqued. Any machine shops around that can do some measurements for you?

Wed Mar 08, 2023 12:05 pm

no machine shops with 2 hours that will measure anything 'Lesser' than a Porsche.

seriously tho, no machine shops.

mics and telescoping bore gauges on the way.....Mo money, Mo money

Wed Mar 08, 2023 1:44 pm

Been suggested to try and scrap bearing if ID is off.

Given my track history.........that seems an unlikely path to success Lol.

I have plenty to practice on tho.

Wed Mar 08, 2023 6:33 pm

Best place to START is measuring the crankshaft with a micrometer, and using a dial bore gauge to measure bearing ID.

This is not the fastest or best way to do it, but it is the most foolproof, so lets do that before you get me too excited about how to check every dimension on the blueprint.

Clatter just drove us all nuts with his "crank no spin" saga.
He LEARNED to use a dial bore gauge and that showed that the clearance was ok, but crank still no spin.... so at that point he started losing faith in the whole process and running in circles, distracted with info overload.

Turned out it was the crank in the end, Crank was tapered and too big near the #1 radius. He had just measured the crank in one spot. oops

Thu Mar 09, 2023 6:46 am

Good plan. I had a guy help with measuring crank and case bout 5 months ago when engine ate cam gear.

But that was before the bore. Just waiting on the tools!

Thanks all!