You should never lubricate the back of the bearings. You never install piston & ring assemblies dry. The ring gaps in the new rings are still too big. A 2mm ring gap is excessive. It needs to be less than half that gap. When cranks are machined, the bearing size is said to be UNDERSIZE, not oversize. Regarding the camshaft, remove that sprocket, & throw it in the bin. Replace it with an alloy sprocket. The dots on the top of the pistons denote to front of engine. The oil holes in the conrods are there to spray oil onto the cylinder walls. Don't bother arguing with me on this, because I used to do this work for a living, both full time & part time.
Thanks for your advice, right or wrong this is the way I choose to build my motors and to date I’ve not had an issue. For some clarity the Pistons and rings were not installed dry as you state. Ring gap measurements were an approximate measurement as stated in the video and the old rig was 2mm not the new ring was considerably smaller. Thanks for watching and your comment, enjoy the upcoming episodes.
It appears to me that you have plain old cast iron compression rings. Those are what I prefer when not reboring cylinders as I have found them to seat quickly and be more forgiving of imperfections in used bores. I did a 327 Chevy 45 years ago using basically the same methods as you. It was a sweet runner and gave me probably 75% life of a new engine. Keep doing what works for you!
Hi there again. I worked for a company that built 1000 engines a week . They never lubricated back of bearings. There is no Benefit. Plenty of oil between the crank and the bearing. Clearances will change if you have lube under the bearing. But on a basic rebuild probably has heaps of clearance like your doing. Ring gap is 3-4 thou per inch. So your ring gap should be about .012 “ approximately not .080” But still enjoy your video. Cheers
Thanks for the info mate really appreciate it as this is how we learn. Putting lube on the back of the shells is something an old engine builder of 75+ years told me he used to make sure they seat properly. right or wrong so far has worked for me. Glad your enjoying the videos. Cheers.
Had an FJ years ago that I repowered with a modded 253. The grey motor I took out looked like it may have been something a little special, it had a little alloy tag on the side that said something like "Genuine Holden sports balanced engine". For the life of me I cannot remember what I did with that motor, but then it was 40 odd years ago.
Interesting, never seen that before but would like to find out more. I did consider a 253 v8 but it’s getting difficult to licence them and the engineering process is getting out off hand. Cheers and enjoy. Cheers and enjoy.
It's Amazing all these engine building experts in the comments that I've never heard of... It doesn't matter if you oil the back of the bearings, as soon as the engine is running oil will get there. There are no seals to prevent it and the machining process provides multiple paths for oil to get behind the bearings. You arm chair experts need to do some research. I've been doing this for 50 years. I've never torn down an engine and the back of the bearings were dry.
Hit the nail on the head Jeffrey, could not have said it any better. There is many reasons engines fail and this is not one of them. This was taught to me by an old qualified mechanic who worked on them when they first came out pre 1948. He worked as a mechanic from the age of 14 until his passing last year aged 96. So he knew a thing or two…… Cheers mate enjoy the videos. Regards Peter.
i built dirt track engines for years when setting oil clearences on the bearing never have it wet because that space tightened toward the crank in micro measurement you can see this easily not so easy with the naked eye... for what your doing it is nothing i see wrong with it it kinda like the oil thing which is better you ask a thousand people you gonna get at least 500 diff answers.. in the end it works !!!!!!!!!!!!!! for you..
Be careful when cleaning the ring lands with the broken end of a ring, and for that matter, a wire brush. The upper and particularly the lower faces are sealing surfaces for the rings and a scratch on them will cause some amount of blow-by.
Thanks for that, I’m always careful using that method. Since purchased a ring grove cleaner so should make life a little easier next time. Cheers and enjoy.
@@petersbackyardbuilds I have a ring groove cleaner but still prefer the broken ring method. Near 50 years as a mechanic gives one the "feel" to get it right.
Hi James, yes I have used it before when building a performance engine. I had checked the rods off camera using an internal micrometer just to make sure nothing obviously stood out.
Including you two others have said this. Please explain why? FYI. A couple different engine builder friends of mine one in particular who was building engines for 75+ years until late last year when sadly he passed aged 95 said this is good practice to help seat the bearings properly as bearings mainly fail from incorrect placement/ fitment. Cheer for the feedback. Enjoy the build.
You want the bearings to seat to the metal of the block and for the crush to be correct. By adding lube you are potentially adding to the chance of a spun bearing. As mentioned before the tolerance will be all over the place too depending on how much was added to each particular bearing shell. Of course this is my own opinion and if this is the way you wish to do it then go for your life.
@@petersbackyardbuilds i understand that what he is saying it closes the gap on start up so it instantly clearences itself. i just myself never practiced that but hey what works for you dont change
I was under the impression that the reason for NOT lubing the under side of crank and conrod bearings isn’t due to an added risk of spinning a bearing, but was more due to the helping DIRECT heat transfer away from the journals, through the bearings, to the block and conrods. I’m not a professional engine builder so I could be wrong though. I’d like to know peoples thoughts on this…
Hi Casey, in my experience a spun bearing is not caused from excessive lubricant, it’s generally the opposite lack of lubricant causing excessive heat which leads to it seizing to the crank than spinning in the journal. It’s a divided topic, on older engines like this one it is what I choose to do and has never let me down. If this engine was professionally bored, had the crank ground or a race engine when the tolerances are tighter etc would I lube the backs of the bearings. No. Cheers and enjoy the videos.
You should never lubricate the back of the bearings. You never install piston & ring assemblies dry. The ring gaps in the new rings are still too big. A 2mm ring gap is excessive. It needs to be less than half that gap. When cranks are machined, the bearing size is said to be UNDERSIZE, not oversize. Regarding the camshaft, remove that sprocket, & throw it in the bin. Replace it with an alloy sprocket. The dots on the top of the pistons denote to front of engine. The oil holes in the conrods are there to spray oil onto the cylinder walls. Don't bother arguing with me on this, because I used to do this work for a living, both full time & part time.
Thanks for your advice, right or wrong this is the way I choose to build my motors and to date I’ve not had an issue. For some clarity the Pistons and rings were not installed dry as you state.
Ring gap measurements were an approximate measurement as stated in the video and the old rig was 2mm not the new ring was considerably smaller.
Thanks for watching and your comment, enjoy the upcoming episodes.
You are correct do not lube back of bearings
I have to agree: how do you think that #2 rod bearing spun to begin with?
@@jimwinchester339 It wasn't because of oil behind the bearing.
It appears to me that you have plain old cast iron compression rings. Those are what I prefer when not reboring cylinders as I have found them to seat quickly and be more forgiving of imperfections in used bores. I did a 327 Chevy 45 years ago using basically the same methods as you. It was a sweet runner and gave me probably 75% life of a new engine. Keep doing what works for you!
Hi and thank you.
Appreciate your kind words and feedback.
Cheers and enjoy.
Hi there again.
I worked for a company that built 1000 engines a week . They never lubricated back of bearings.
There is no Benefit.
Plenty of oil between the crank and the bearing.
Clearances will change if you have lube under the bearing.
But on a basic rebuild probably has heaps of clearance like your doing.
Ring gap is 3-4 thou per inch. So your ring gap should be about .012 “ approximately not .080”
But still enjoy your video.
Cheers
Thanks for the info mate really appreciate it as this is how we learn.
Putting lube on the back of the shells is something an old engine builder of 75+ years told me he used to make sure they seat properly. right or wrong so far has worked for me.
Glad your enjoying the videos.
Cheers.
Had an FJ years ago that I repowered with a modded 253.
The grey motor I took out looked like it may have been something a little special, it had a little alloy tag on the side that said something like "Genuine Holden sports balanced engine".
For the life of me I cannot remember what I did with that motor, but then it was 40 odd years ago.
Interesting, never seen that before but would like to find out more.
I did consider a 253 v8 but it’s getting difficult to licence them and the engineering process is getting out off hand.
Cheers and enjoy.
Cheers and enjoy.
It's Amazing all these engine building experts in the comments that I've never heard of...
It doesn't matter if you oil the back of the bearings, as soon as the engine is running oil will get there. There are no seals to prevent it and the machining process provides multiple paths for oil to get behind the bearings. You arm chair experts need to do some research. I've been doing this for 50 years. I've never torn down an engine and the back of the bearings were dry.
Hit the nail on the head Jeffrey, could not have said it any better.
There is many reasons engines fail and this is not one of them.
This was taught to me by an old qualified mechanic who worked on them when they first came out pre 1948.
He worked as a mechanic from the age of 14 until his passing last year aged 96.
So he knew a thing or two……
Cheers mate enjoy the videos.
Regards
Peter.
i built dirt track engines for years when setting oil clearences on the bearing never have it wet because that space tightened toward the crank in micro measurement you can see this easily not so easy with the naked eye... for what your doing it is nothing i see wrong with it it kinda like the oil thing which is better you ask a thousand people you gonna get at least 500 diff answers.. in the end it works !!!!!!!!!!!!!! for you..
Thanks mate appreciate it.
Yes it works for me on these engines.
Be careful when cleaning the ring lands with the broken end of a ring, and for that matter, a wire brush. The upper and particularly the lower faces are sealing surfaces for the rings and a scratch on them will cause some amount of blow-by.
Thanks for that, I’m always careful using that method.
Since purchased a ring grove cleaner so should make life a little easier next time.
Cheers and enjoy.
@@petersbackyardbuilds I have a ring groove cleaner but still prefer the broken ring method.
Near 50 years as a mechanic gives one the "feel" to get it right.
Cheers mate I’ll keep that in mind.
I find the broken ring way to be fine so shall see how the new tool works.
Your ring gap in still a little to big. I like to use oversize rings and file the gap to minimum spec. Just my opinion.😀
Question : mate did u clean out those oil channel tube on the crank ?
Sure did, if you watch carefully before I remove crank from lathe I used brake cleaner and compressed air.
@@petersbackyardbuilds i so that but also so a blocked oil port ith crank polish i figured you cleaned them more off camera as so many do.
Yes cleaned the ports thoroughly.
What brand rings did you get? I'm doing a similar thing but with a honda
Hi mate, ACL make good products. Never had an issue with them.
Cheers.
You should plastigage the crank
Thanks mate as the crank wasn’t machined and I’m only giving it a refresh it’s not necessary in my opinion.
Cheers and enjoy the videos.
@@petersbackyardbuilds The rods could be out of round not just the crank. Have you used or know how to use plastigage ?
Hi James, yes I have used it before when building a performance engine.
I had checked the rods off camera using an internal micrometer just to make sure nothing obviously stood out.
@@petersbackyardbuilds Those engines are tractors to i guess
They sure are, all 40hp if your lucky. Enjoy the videos.
Cheers
how to spin a bearing lube the back.
Do your research. A bearing doesn’t spin because of lube on the back.
Question. Did you lube the bearing shells between the block and caps?
Yes, very slight amount helps when aligning caps.
Should never lubricate bearing backs. Takes away tolerances and it lubricates what ?
Including you two others have said this.
Please explain why?
FYI.
A couple different engine builder friends of mine one in particular who was building engines for 75+ years until late last year when sadly he passed aged 95 said this is good practice to help seat the bearings properly as bearings mainly fail from incorrect placement/ fitment.
Cheer for the feedback.
Enjoy the build.
You want the bearings to seat to the metal of the block and for the crush to be correct. By adding lube you are potentially adding to the chance of a spun bearing. As mentioned before the tolerance will be all over the place too depending on how much was added to each particular bearing shell. Of course this is my own opinion and if this is the way you wish to do it then go for your life.
@@petersbackyardbuilds i understand that what he is saying it closes the gap on start up so it instantly clearences itself. i just myself never practiced that but hey what works for you dont change
I was under the impression that the reason for NOT lubing the under side of crank and conrod bearings isn’t due to an added risk of spinning a bearing, but was more due to the helping DIRECT heat transfer away from the journals, through the bearings, to the block and conrods.
I’m not a professional engine builder so I could be wrong though.
I’d like to know peoples thoughts on this…
Hi Casey, in my experience a spun bearing is not caused from excessive lubricant, it’s generally the opposite lack of lubricant causing excessive heat which leads to it seizing to the crank than spinning in the journal.
It’s a divided topic, on older engines like this one it is what I choose to do and has never let me down. If this engine was professionally bored, had the crank ground or a race engine when the tolerances are tighter etc would I lube the backs of the bearings. No.
Cheers and enjoy the videos.