How to balance an Engine?

[Challenger_7]

Hello again and please enlighten me some more.
The flexplate arrived 2 days ago and the mech will be taking my car in tomorrow.
I opened the package and found an installation note from B&M which warns about ensuring perfect alignment between the engine and transmission and ensuring that this should not exceed .008". Everything is understood in that paper, photo attached, except the part where they explain how to check the alignment, (the higlighted part). They say "Rigidly attach indicator to crankshaft and indicate on the oil pump bore in the case". What is "indicator", a special tool or is it part of the engine?
A photo will also help, if possible.

Thanks again.

[John_Kunkel]

While dial checking the case/crank alignment is a good idea, it's seldom done because it requires emptying the case.

The the "flex" in flexplate is intended to allow for some misalignment. The B&M flexplate is less flexible than the original factory style but few people experience problems because of it so just bolt it in and go.

It's a good idea to trial bolt the flexplate to the converter to be sure all of the holes line up before installing it on the crank.

[firefighter3931]

While dial checking the case/crank alignment is a good idea, it's seldom done because it requires emptying the case.

The the "flex" in flexplate is intended to allow for some misalignment. The B&M flexplate is less flexible than the original factory style but few people experience problems because of it so just bolt it in and go.

It's a good idea to trial bolt the flexplate to the converter to be sure all of the holes line up before installing it on the crank.

Just bolt it in and go ! 


Ron

[Challenger_7]

The the "flex" in flexplate is intended to allow for some misalignment. The B&M flexplate is less flexible than the original factory style but few people experience problems because of it so just bolt it in and go.

Ok thank you both, I will do just that, bolt on and go!
But for the sake of argument, if the B&M is less flexible than the original one, how then is it going to do a better job and rid me of the vibrations Just trying to follow the logic of things.

[firefighter3931]

[But for the sake of argument, if the B&M is less flexible than the original one, how then is it going to do a better job and rid me of the vibrations Just trying to follow the logic of things.

The scallop (cut out) in the B&M flexplate is what fixes the balance issue.

The stronger SFI rating means it won't break when you drive hard. 



Ron

[Challenger_7]

Thank you Ron. Where would we be without the wonders of technology

My luck that the mechanic has caught a serious flu, so I will have to wait a bit longer before feeding you back.

Have a lovely week end All.

Farouk

[Challenger_7]

As I had mentioned in my other topic, seeing so many irregularities in the transmission/converter, I decided to open the engine up and check things inside, before installing the "B&M" flexplate. The engine is confirmed to be a 1970 400 engine (with a cast date on the block 11.10.70), originally blue in color, and has signs of corrosion inside one of the cylinders. somehow water must have gotten inside and stayed there for a very long time, thus causing pit marks in that particular cylinder.
The heads have been "shaved" once, and there is leakage between some cylinders at the cylinder head gaskets. The cylinders have already been bored 20 thou over, and will probably need another 20 to clear the pit marks of the corrosion.
The crank shaft has the main bearings standard, and the piston bearings at ten thou over. All will need to be machined another ten thou so will be left with main bearings at ten over, and piston bearings at 20. I suppose it is acceptable to have a difference here?
Pistons are the flat type and will be replace with oversize ones. Of course the valves will be grinded or lapped, as the need arises, and everything else checked.
The cam shaft seems to be a non standard one, probably a higher rpm one, but no idea what. I will take some measurements of the cams to have some idea.

With this, and having taken a few pictures of the various parts pof the engine, I left the mechanic to send the engine to the machinist on monday and carry on with the work.
Any comments or words of caustion willbe appreciated.

Thanks, Farouk

[firefighter3931]

The engine is confirmed to be a 1970 400 engine (with a cast date on the block 11.10.70), originally blue in color, and has signs of corrosion inside one of the cylinders. somehow water must have gotten inside and stayed there for a very long time, thus causing pit marks in that particular cylinder.

Thanks, Farouk

Farouk, are you sure on those casting dates ? A 1970 "B" engine would be a 383...not a 400.  Maybe you should have the machinist measure the bores to see what you've got there. The 400ci didn't go into production until the 1972 model year.


Ron

[Challenger_7]

Yet again our Guru proves to be on the alert all the time Ok blame me for my limited knowledge , and as usual, help me clarify some points.

1. I saw on the side of the body of the engine, below the actual engine number, what appeared to be the number I quoted. I went back to the pictures and looked again, funnily the one with paint on looked clearer than having brushed the paint off, and what seems to be the number now is 11.16.73. Does this make sense. Attached is the pic of the casting date after brushing.
2. The engine number photo is also attached. There is a number that appears to be 3698630.400.(something looking like I or 1 after the 400).
3. Then on the front of the engine, there is a stamp with some numbers on it. Pls see attached photo. What are these?
4. I have also attached the photo of the piston that is on the engine now, and in any case, I asked the machinist to measure the cylinder for me.
5. Now the first of the reports coming back on the cylinder heads is that there is a bit of play on the valve guides, and the mechanic says there are no new guides for this engine. What they normally do is find the same size valve with a thicker stem and bore the guides accordingly. Is this correct or I can find new guides??
6. There is also the letters XL cast on the upper front of the engine. Any important significance?

Cheers, Farouk

[Challenger_7]

Two other things; out of the main bearings (five in all), only the middle one has a bearing with a lip (or whatever you call it). Photo attached. Is this normal, and as you can see, the lip does not go all the way down, is this correct?

I also included a photo of the "fleplate" that was on the engine, also very weird looking. Is this also normal? I would have expected to see a round one. You can also see the new converter under it with the weights grinded off, as suggested.

Thanks again, Farouk

[Steve P.]

All normal. The bearing in your hand is the THRUST BEARING. It keeps the crank from moving too far forward and back. The flex plate is mopar stock. Nothing strange there.

I totally believe all motors should be internally balanced. Many are not and I don't know why, but this leaves nothing to go wrong.

And for what it's worth, I met a guy a few weeks ago that has used many 440 Source kits and loves them. Never any problems. He does have his machine shop check EVERYTHING though, just in case...

[firefighter3931]

  Steve's observations are right on the money. 

I don't see anything to be concerned about in there. Just have the block hot tanked and magnafluxed to check for cracks. Also have the cylinders measured for taper to see if it needs an overbore. 



Ron

[Challenger_7]

Thank you both for the replies. I feel much better now, and thanks Steve for your assurance on the 440 source kits. It is appreciated
Ron, the cylinders will have to be rebored due to some wear and rust on one particular cylinder that has developed into pits. If we can find 40 oversize pistons available here, this is where we will have to go, otherwise we will insert a new sleeve (quicker and cheaper than importing new set of pistons).

Will keep you posted. By the way, do the XL letters cast on the front of the engine have any significant meaning?

Thanks

[Challenger_7]

Hello friends.
I have completed reboring the engine to 20 over, crank regrinded 10/20 over and installed everything new and now getting ready to paint the engine.

At this point and out of curiosity, I asked the mechanic to show me the harmonic balancer and here are the pictures. One thing attracted my attention, the part number on it, which has "318" at the end. Does this mean that it is for a 318 engine? If not, how can I get a confirmation if this is correct for my 400 block or not

I woud appreciate a quick response in case I need to change it.

Thanks and hope you all have a lovely week end.

Farouk

[Challenger_7]

The long journey is almost over, and we will see if all worked out well.

The engine has been completely overhauled, assembled back and today was being re-installed into the car. Hopefully we will start it tomorrow or the day after.
Keeping fingers crossed that the B&M flexplate will do the trick and will have no more vibrations

Attached is a pic of the back of the engine, now painted orange.

[firefighter3931]

Looks very nice Farouk....hopefully the flexplate fixes the vibration issue. 


Ron

[Steve P.]

I think you'll be good to go.. Let us know.............   

[Challenger_7]

Hey guys, guess what.
Thanks to your good advice and guidance, the engine is purring like a tame cat All I need now is a new carb, as the current one is too small, but good enough to run the car in.
By the way, what would be the recommended running in proceedure. 500 KM, change of oil/filter then 1500KM before a new change? Pls advise.

Summary of events: Bought the car with a badly vibrating engine and leaking g/box. Ended changing all components of the gearbox, new converter (neutral balance), a B&M flexplate, reconditioned the engine completely (new cylinder sleeves) and new valves, new starter and new fan blade (but with clutch as I could not find the same type).
Hopefully tomorrow the car will be released to me to start the running in of the engine, after which time I will make one final post on this thread.

Lesson learned: Vibrating engine: install B&M flexplate, use neutral converter, all rest being normal you should be ok!

Thanks to all who contributed here, and a special thanks to Ron for being there all the time.

Attached photo is after having started the engine.

Cheers, Farouk

[firefighter3931]

That is excellent news Farouk ! 

I would change the oil/filter immediately after breakin and again at 500 miles then again at 1500 miles. After that normal intervals...say every 3000 miles or so. 

Enjoy the car and don't beat on it to hard for the first few weeks....3500-4000rpm short bursts to seat the new rings. After that....let er RIP ! 


Ron

[Steve P.]

  All the way..   Good luck buddy..   

[Challenger_7]

Ron and all. I took the car out on Saturday and Sunday and did 300 miles of gentle breaking in including the recommended short bursts. Only very occasionally going to 3500.
I was rather sad to note that there are still vibrations in the engine at different RPMs. It is nothing compared to what was there before, but they are still there
They are more significant at some levels than others. What do I do, and how bad is this for the engine?
Apart from that, the car handles like a dream and I discovered that the car, whilst originally was a 6 cyl car, was actaually exported to Lebanon, purchased here from the dealer and has been very well preserved. Everything in it is still original except for the engine/gearbox. Also it used to be Orange/white top Vynil, white interior but now changed to red/black/black. It stayed with one owner till 3 years ago whereby the new owner changed the engine to the 400, sold it to another person from whom I bought the car. Both owners never really drove the car.

Please tell me there is still something I can do to get rid of the vibrations

Just sharing with you, attached photo taken on Saturday just outside the city of Beirut

Cheers

[firefighter3931]

Farouk, are you sure it's coming from the engine ? Try reving up the motor in park and see if you have any vibration. It mght be a u-joint or driveshaft out of balance.


Ron

[Challenger_7]

Yes Ron I did check it out whilst not in motion.

According to the RPM counter attached to it (i.e. not 100% sure of its accuracy), at 900 the whole car rattles loudly, 1200 rattles less, 1700 rattles a bit louder, 2400 or there about rattles enough to vibrate even the console plate.
In between the rattling sort of fades away, or sways off and comes back but softly.

Please advise me what to do, even if I have to pukk the engine down again.

Regards

[firefighter3931]

Damn, that is disappointing. Ok, it's obvious something is causing the engine to go way out of balance. I would start by checking the pullies and belts.....remove the belts and fire up the engine to see if it still vibrates. Next, check the tq converter bolts to make sure that they haven't loosened off.

It's gonna be an internal or external balance issue. Start with the external (easy) things first. I'm starting to question your torque converter....i wish there was an easy way to verify neutral balance with it.


Ron

[Challenger_7]

Thanks Ron, I will do as you say in due course and let you know.

Can you explain to me what is the meaning of "Verifying neutral balance with it"? Are you saying to verify if the converter is indeed balanced without the weights on it?
If you recall, when I bought this converter, it had weights on it that we grinded off. I can always look for a new one that comes with no weights, and pray that it is indeed neutral balanced and try it on the engine.

Farouk