Exactly !!!!! This is the point we are trying to get across.

When I was in the biz 4 cyl balance was $125. When parts for the old balance machine went NLA they spent $28000. for a new computer driven machine. Price of balance went up. I built my first Cooper S engine in 73/74 and when I started it and got it running perfect it shook so bad at certian RPMs I took it apart and had it balanced and installed new rings. Never built another without balance. Steve (CTR)

Hope your build works out OK.

Mine is but a fairly standard 1293 (because that was the bore available) but with new bits - cam/lifters/push rods, connecting rods, crank, lightweight flywheel, clutch....

All rotating bits will be balanced by a shop that has done A Series engines for quite some time...including my 1380...at a cost of $125 (price for 4 cylinder engines).  The shop is not in a high rent district and that probably helps.

My bits are ready for balancing...the second engine needs a SPI clutch (an MPI clutch was sent) and crank lapped then both can go off together

For the sake of a few bolts and 1/2 hour's time i would un assemble it and get it balanced. I hope when you get it all together and running it does not have any unusual vibrations as you will have wished you took the advice. Good luck with the build.

Mal stop me man, Hey I'm OK. I'm sure it will be just fine it was before. What I do could be called silk purse. I try for the very best result. I'm sure you do as well. Let us know how it goes. Steve (CTR)

The engine is already assembled.

 

 

 

 

 

 

The engine is already assembled.

 

 

 

 

 

 

Spend another $20 and get the crank checked, piece of mind is worth it.

I just got my flywheel and clutch back from the machine shop.  They are balanced and no metal had to come off or be added.  It only cost me $20.  Next I will take in a new harmonic balancer to be balanced.

dog...do yourself fav. not trying to be smart here..... but your way over your head in this dept.

your best bet and the smartest thing for you to do is.....

find the best machine shop around... next... take the block, crank, rod's, piston's. cam and bearings, frt. balancer, flywheel, piston rings...the whole shooting match along with the " Correct " eng. spec's from the shop manual which you can buy from Don, to him..

ask him nicely if would assemble the lower end for you. balancing , align-bore, tell him, you want the competition package done on her.

don't even ask him " how much " when he calls and says it ready, just go down there with a wad of cash and pay the man and thank him.

do you know how to set the ring end gap? PLASTIGAUGE the crank bearings? which way the piston rings go on the piston as well as how to index them on the piston? and this is just the tip of the iceberg.

how to install and prime the oil pump??? set cam timing??? i know you don't ......

with that done and you somehow manage to assemble the rest correctly.....you will be able to beat the liven crap out of her for a long time. let them pistons reach for the stars. it'll take it...

dog... if you don't do this...make sure you have road side asst.

Not that it matters but FYI I began working in the auto aftermarket in 1965 at age 16 with a work permit. I managed the largest auto machine shop in eastern Va. for 25 years. They celibrate their 95th this year. I have been retired from there 15 years. I am still welcome to drop by and use any machine in the shop. Little known fact Vizard has driven my race cars and I have a collection of pre publication manuscirpts I have proof read for him. I have nothing to gain from leading you astray. Do what you want to. As dear old dad said advice is worth what it costs you and this I give you free. Steve (CTR)

PS: Nick Swift came over and drove one of my vintage cars to a VIR Gold Cup win as well. 

 

My reply was based on your question.

That said I agree with Steve and Malcolm about balancing the crank. For not a lot of money the crank could/should be done also.

Your engine, your dime.

Your dime do what you want but over the years i have seen and heard about many non Mini machine shops and their opinions of what needs to be done and not and the engine failures/problems soon after re builds. For the small cost while it is all apart and especially as it is a 1275 3 bearing engine why wouldn't you do it ?????? - asinine not to imo. Just my 02c.

I trust my engine rebuilder implicitly.  Someone who has been rebuilding engines for 30 years+ and is still in business should know what they are doing.  If my crankshaft has only been reduced by .010 and .010 mains and rods is shouldn’t change the factory balancing.  According to Vizard’s book crank balancing is fine if you have the cash and the time, but not really cost-effective.  Granted, it does make for a smoother revving engine, that is assuming that it is out of balance in the first place

Really !!!!! I would look elsewhere and for a knowledgeable Mini person to do my work if i were you, a Mini crank absolutely needs balancing don't do it and you will regret it down the road.

I sometimes feel I'm wasting my time talking to you guys. If you don't have your shaft balanced you will have wasted your money. In the 25 years I worked at an auto machine shop I'd guess I worked on over 1000 balance jobs. In our hay day we got 17 sets of V8 heads out each day. Had two crank grinders running all the time. Do what you want to do. Steve (CTR)

OK, I just found out my engine rebuilder DOES do balancing.  He indicated that 4 cylinder cranks usually are fine and don't need balancing.  I need to take in my pressure plate and flywheel.   He doesn't need the clutch.  I think that I will buy a new harmonic balancer, they appear to be cheap anyway.  Sounds like $75 for the job, such a deal.

Maybe I should not go here, but I would not bother with a rebuild damper/ balancer. All I have seen are junk. They have had run out in and out up and down. MSC offers new as well as several other suppliers. That must be a clutch only price. The boys here get $125. to do the flywheel, back plate diaphram, pulley and damper using my balanced crank. Doing the rods, pistons and crank with all rotating parts other than disc current price is $250 to $280. Steve (CTR)

//damperdoctor.com/index.php?route=common/home

You can get your damper repaired at this place. The original rubber is probably hard as a rock now. $50 for balancing the motor is a good price.

Jerry

I would order a new front pulley and damper. If reusing the old pulley check for seal wear and possible wear in the bore and keyway. I keep a crank on hand that has been balanced by it's self to use as a mandrel to mount front or rear bits for balance. Pull your crank and have it balanced then have them add parts and balance each as they go. Four cyl engines have the worst natural balance characteristics. I have always felt balance is a good way to spend money on these engines. As for the clutch disc don't bother with it as it is light and stops in a different place each time. The heavy race paddle disc should be balanced. This is what I think others may dissagree. Steve (CTR)

Randy, I've been using Fort Wayne clutch in (Big surprise here) in Fort Wayne IN for years. They make/rebuild clutches with Kevlar and ceramic, and can balance the flywheel and pressure plate (not disc/diaphram). As long as it can be mounted on his balancer. They also do driveline repair.

They're average on price, around $40-50 to balance.

They did a Kevlar clutch for my ole 911, machine flywheel & pp, rebuild disc w/Kevlar was close to $400 w/shipping.

FW Clutch have rebuilt a number of NLA clutches for vintage cars we've worked on. I'm sure there are more, that's who our shop and myself have used.

//www.fortwayneclutch.com/

SxS