Help analyze my engine
Thread Starter
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
Jackson,
Thanks for the advice. I will try to weigh the parts to find the closest match. can I swap the whole Piston/Rod combo or should I weigh and swap just the rod?
Also, do you think I will have a problem pressing out the Pin with a vice or will I need a stronger press?
Thanks again for your help.
Thanks for the advice. I will try to weigh the parts to find the closest match. can I swap the whole Piston/Rod combo or should I weigh and swap just the rod?
Also, do you think I will have a problem pressing out the Pin with a vice or will I need a stronger press?
Thanks again for your help.
Thread Starter
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
Don't skip the machine shop check on your parts, I know what your thinking this is a running engine when I took it apart. There are a lot of good reasons to have the shop look stuff over I'm just going to mention one, having a few thousands more clearence in the bores if you were to just try and hone the cylinders is not ideal but won't hurt the rings are still going to seal every thing will still be going up down Ok. but what is a big deal is the sizing on your big end of your rods and the rod journals.You need to have a shop with the proper tools machines do that and your going to need new rod bolts.
Does anyone know a good machine shop in Chicago?
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Thanks for the nudge here. I was hoping to do this myself, but you raise good points. I did carefully measure all of the journals and they came up very clean and consistent, with no out of round or taper either. The rods scare me a bit here.
Does anyone know a good machine shop in Chicago?
Does anyone know a good machine shop in Chicago?
to a machine shop, You don't know how many times the rod bolts
have been torqued and streched, $ 60.00 bucks for new rod bolts
and what ever the machine shop charges for resizing is cheap insurance. Let them check your rods all out first before buying the rod bolts ARP is a good brand for rod bolts.
Last edited by Little Mouse; Jan 4, 2008 at 12:59 PM.
Thread Starter
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
I measured the journals with a mechanical calipar in several different degrees and across each journal. I realize that the actual measurement tolerance could be off with a calipar, but the consistency from measurement to measurement should be accurate. Each journal measured where it should and with 0 deviation across the different journals. I had also plastigaged several rods and mains to check oil clearance. Each came up about .003.
I heeded your advise and called a machine shop. I am thinking of getting new rods and pistons and honing from 30 over to 40 over. They could check over the block and crank at that time. This would also let me pick a compression ratio that I like. He said that I could get new rods for about the cost of bolts and labor for tearing them apart. I will likely need 1 new piston and possibly one new rod anyways.
I heeded your advise and called a machine shop. I am thinking of getting new rods and pistons and honing from 30 over to 40 over. They could check over the block and crank at that time. This would also let me pick a compression ratio that I like. He said that I could get new rods for about the cost of bolts and labor for tearing them apart. I will likely need 1 new piston and possibly one new rod anyways.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
I measured the journals with a mechanical calipar in several different degrees and across each journal. I realize that the actual measurement tolerance could be off with a calipar, but the consistency from measurement to measurement should be accurate. Each journal measured where it should and with 0 deviation across the different journals. I had also plastigaged several rods and mains to check oil clearance. Each came up about .003.
I heeded your advise and called a machine shop. I am thinking of getting new rods and pistons and honing from 30 over to 40 over. They could check over the block and crank at that time. This would also let me pick a compression ratio that I like. He said that I could get new rods for about the cost of bolts and labor for tearing them apart. I will likely need 1 new piston and possibly one new rod anyways.
I heeded your advise and called a machine shop. I am thinking of getting new rods and pistons and honing from 30 over to 40 over. They could check over the block and crank at that time. This would also let me pick a compression ratio that I like. He said that I could get new rods for about the cost of bolts and labor for tearing them apart. I will likely need 1 new piston and possibly one new rod anyways.
something like the cheaper low grade chinese stuff. hes probably talking about a $300.00 set of 5140 grade chinese steel rods.
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Thread Starter
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
These pistons have two separate pins pressed in from both sides. I can see the gap between the two pins. Is this irregular or unsafe. I have not seen this in any of the books that I read.
Thread Starter
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
I honed the cylinders and cleaned the block this weekend. The bores cleaned up pretty nicely. There were a couple of wears spots that did not get any real contact with the hone. They are fairly small and thought I would let them go. Would you guys take a look and let me know your thoughts?
Thanks
Thanks
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
I honed the cylinders and cleaned the block this weekend. The bores cleaned up pretty nicely. There were a couple of wears spots that did not get any real contact with the hone. They are fairly small and thought I would let them go. Would you guys take a look and let me know your thoughts?
Thanks
Thanks
Also ... too bad you didn't put up pics of 2 pins in each piston ... could be those are wrist pin "buttons" for a floating pin ... I'm guessing since I cannot see it at all.
I've never seen any motor with 2 separate wrist pins ... but I have seen a floating pin with a button on each side. I've never seen a pressed pin with buttons but I guess it's possible ... I guess. And ... there could be buttons with spirolocks beneath ... who knows? Hopefully your shop will inspect & measure closely ... & will shed much light on this & guide you. Let us know what the shop finds, measures & suggests.
Thread Starter
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
I'll post a pic of the pins. I saw a burned spot on one, but didn't know what to make of it at the time. I now believe the mechanic/hack, cut the pin in half (hence the burn) and pressed in from both sides. I just can't figure out why. Here is a pic:
What is the best way to asses the condition of my bores. I checked the taper with an old ring and the ring gap only changed .001 from top to bottom, checked in several places. The piston to cylinder gap was tight with a .004 feeler. The book said .0045 is the limit. I don't like the scratches, but they are very thin (fingernail won't catch). Any ideas on checking of the bores? I will try to make a bore gauge and check for out of round.
I read a book that said cast rings seal better than Moly when the bore is not perfectly straight. Have you heard this? I don't mind going with cast rings.
What is the best way to asses the condition of my bores. I checked the taper with an old ring and the ring gap only changed .001 from top to bottom, checked in several places. The piston to cylinder gap was tight with a .004 feeler. The book said .0045 is the limit. I don't like the scratches, but they are very thin (fingernail won't catch). Any ideas on checking of the bores? I will try to make a bore gauge and check for out of round.
I read a book that said cast rings seal better than Moly when the bore is not perfectly straight. Have you heard this? I don't mind going with cast rings.
Thread Starter
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
Ok. tonight I fabricated a bore gauge. I took a small welding rod down to exactly 4.279). I then used feeler gauges of different sizes to measure a couple of bores. I came up with:
parallel with Crank: 4.282 @ top / 4.2815@ bottom of ring travel
90* to Crank: 4.283 @ top / 4.282@ bottom
Is this enough to warrant a bore 10 over?
I will bring it to a shop for final meaurements, but I am trying to see what type of pistons I can work with. There are more avilable for 30 over than 40 over.
Thanks.
parallel with Crank: 4.282 @ top / 4.2815@ bottom of ring travel
90* to Crank: 4.283 @ top / 4.282@ bottom
Is this enough to warrant a bore 10 over?
I will bring it to a shop for final meaurements, but I am trying to see what type of pistons I can work with. There are more avilable for 30 over than 40 over.
Thanks.
