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MGB Talk to me about bottom end bearings

Thanks folks. New bearings will be going in, simple and cheap enough to do. Will need help and advice as usual as it's my first time doing this, but excited to dive in when I get some time.
 
Any progress Drew?

You may want to check out "Plastigauge" as well. Give you a good idea as to clearances before final assembly.

And as there seems to be another, more comprehensive engine build in your future, a set of micrometers could be useful tools to add to your collection. I'd say hunt E-Bay for those as "lovingly used" Pratt &Whitney or Starrett ones. 1"~2" and 2"~3" to begin with, along with 'standards'. No digitals (just my personal opinion)!
 
I have one apart now that was leaking oil everywhere and was told the motor was fresh. Resealed the whole motor and test drove to find that it was pumping oil out the vent tube.
long story short, broken number 4 piston.....
bits are slow coming now.
 
Gah. BTDT, D. "It's ready to reassemble." DB 2/4 DHC came to us in literal bushel baskets, short block and trans were in the chassis, said to have been rebuilt. Pulled gearbox drainplug and got a quart of water! Sand in wheel bearings, bottom end never touched. Previous "shop" had the car for years, milking the owner. I'm convinced it was sabotage. For us it's always been: "Trust but verify". Precisely why my suggestion for Drew to at least check bearings.
 
Second time it has happened to me. First one was a TD that was told the motor was done. Started it and heard a faint click click. Found that the motor had been sleeved and the recessed area at the bottom had not been revealed enough.
bad for me trusting the customer. In the end it always cost them more than letting me get on with it the way I would normally.
 
Any progress Drew?

Unfortunately no, haven't really even walked out to the shop more than once since my last update. Working long hours/7 days now as we plan for school reopening in the fall, so not sure when I'l be able to get back to this project. Still hoping to at least get a shopping list together for y'alls review in the next week or so.

Thanks for the tip on the micrometers. I have a cheapie digital one for rough measurement, but nothing else.
 
Break-in oil for assembly. And keep all surfaces surgically clean.
I hope you have a torque wrench. The newer ones are really better and more accurate. A spare oil filter cartridge after the break-in period would be a good investment too.
 
With an "indefinite" initial start-up time, I'd use the Lucas additive for final assembly. pd's torque wrench and hospital cleanliness suggestions are appropriate as well.

And as mentioned before, PlastiGauge to insure you don't have some "odd" machining unknown to you. Remember; some of these engines have been passed through MANY hands, some we've seen "rebuilt" on the cheap, one journal differing from the rest. Grantura will agee, certes. In our collective experience I suspect we've seen about everything imaginable done to "just get it out the door!"

Read up on high zinc content oils for run-in and leave the engine "dry" until your initial startup.
 
+1, Doc.
Try Valvoline VR1. It is high zinc content. Lucas is great of assembly. Be sure to coat the bores before fitting pistons, and turn the motor by hand after you install each piston/rod assembly.
 
Thanks all. I already run VR1 in my cars so I'm good there. I'll get these parts ordered and pick up some of that Lucas additive to have on hand for the actual assembly.

In this case I actually know the fellow who rebuilt the engine (in the 1980s) and it's been on the road since then. He will have done things right. May still try and play with some plastigauge just for fun, we'll see. I will verify that all the bearing shells really are marked as .010 before I install the new ones.
 
:thumbsup:
 
Nice shiny pile of parts arrived today. Might have some time to dig in this weekend, we'll see how things go.
 
There is a front and back to pistons and . Do you remember which way they came out ?
 
Engine is still in one piece. I will be carefully marking the caps as I take them off. Pistons are not coming out as head is not coming off. Just doing a bottom end refresh.
 
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