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Rotating assembly problem ...
#578142
01/10/10 01:09 AM
01/10/10 01:09 AM
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Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer
OP
master
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OP
master
Joined: Nov 2003
Posts: 6,293
Rock Springs
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Man... Number 1-2 pistons fell right in, good side clearance about .020-.025...Next Number 3 went right in felt good floated good on the rod. Each rod and piston I install, I have a habit of checking how easy the rods float in the crank, and I spin the motor over etc..Install number four..uh oh...I have no side clearance, well maybe .003-.005 if that. The rod doesnt float on the crank very well. I notice if I pull only the number 4 cap it has the side clearance it needs, this is with #3 still torqued etc. I So I pulled the piston and rod mic the width of the rest of the rods/caps..they are within a thousandth or so. I have some plasti gauge in the tool chest i throw a piece on and re check it..It looks like it has some taper. Its good toward the outer thrust, but toward the center of the rod journal it looses a good .001. Its not binding on the radius or fillet of the crank...I could turn the engine over with the both rods installed, and there was no binding, no mhar'n of the bearing..nothing. I take it back apart, swap bearings..look..look..and look some more... I dont know. I gave up for the evening, but Im going to have a go at it in the A.M...Any suggestions???? I thought about swapping out another piston like #6, or #8, they are all ready installed and have idea clearances/margins etc..I figure if this fixes the problem..It is in that rod, if its still there..its in the crank. This stuff was suppose to be checked out. I paid to have all rods check, and the crank checked, all bearings clearances set to my spec. This really is starting to @!@$ me off. Yes, some problems occur during a build..I feel this type of problem shouldnt have happened. This isnt some $500 small block Chevy that he hurried through the machine shop...Its been there for a year too.  This really sucks.. Its going to be fixed what ever it takes. I can still knock out a few things as work goes. I can continue degree in the camshaft, clay the pistons, check valve to valve through the #4 bore. Figure out a length for Manton push rods.
[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
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Re: Rotating assembly problem ...
[Re: jamesc]
#578144
01/10/10 01:24 AM
01/10/10 01:24 AM
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Joined: Aug 2009
Posts: 2,048
Mooresburg, Tn
'72CudaRacer
top fuel
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top fuel
Joined: Aug 2009
Posts: 2,048
Mooresburg, Tn
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Bob, I'm sure that you checked this, but make sure the rod cap wasn't installed backwards when it was machined. I agree that you should swap another assembly in to check.  Brian
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Re: Rotating assembly problem ...
[Re: '72CudaRacer]
#578146
01/10/10 01:32 AM
01/10/10 01:32 AM
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Joined: Apr 2004
Posts: 1,981
SE Michigan
TS3303
top fuel
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top fuel
Joined: Apr 2004
Posts: 1,981
SE Michigan
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Quote:
Bob,
I agree that you should swap another assembly in to check.
Brian
I agree and if that cures it you may also want to put a different piston on the offending rod and check again.
could be a bad piston as Rowin4 is suggesting.
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Re: Rotating assembly problem ...
[Re: '72CudaRacer]
#578148
01/10/10 01:49 AM
01/10/10 01:49 AM
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Joined: Apr 2004
Posts: 1,981
SE Michigan
TS3303
top fuel
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top fuel
Joined: Apr 2004
Posts: 1,981
SE Michigan
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Quote:
Jim,
Thats a cool head light you got in your hood scoop... Did it come with the Wayne County Speed Shop distributor gear?  
Brian
lol thanks, no wayne county parts on the car or NOS ever. just a cool fall night that we idled too long in the water. little back fire that they put out with compressed air, refired and went on and won the round. I have a larger version but this is Bob's thread.
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Re: Rotating assembly problem ...
[Re: Bob_Coomer]
#578152
01/10/10 10:37 AM
01/10/10 10:37 AM
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Joined: Jan 2003
Posts: 16,928
NC
440Jim
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,928
NC
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Quote:
This stuff was suppose to be checked out. I paid to have all rods check, and the crank checked, all bearings clearances set to my spec.
This really is starting to @!@$ me off.
Yes, some problems occur during a build..I feel this type of problem shouldnt have happened.
Sorry to hear of your assembly problem. Depending on what the cause turns out to be, the individual part checks will only find certain things, and the assembly checks are typically where other problems are found. I doubt they checked a new set of rods for straightness or width variation, etc. likely just the size and bearing clearances. Same with the crank rod journal, I doubt they measured the journal width, just the diameter and maybe for taper etc.
Quote:
I have no side clearance, well maybe .003-.005 if that.
This makes me think the bearing could be rubbing the crank radius. Since all the others had extra side clearance. What bearings and crank do you have?
Good thing you assembled it carefully and found it. Let us know the root cause.
As mentioned, swapping a piston/rod from another hole will tell you a lot. Piston pin bore, piston clearance to rod, bearing shells, rod cap, rod direction, rod width variation (spot), etc. See if the bearing locating tang in the rod is the same distance from the side as a "good" rod.
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Re: Rotating assembly problem ...
[Re: 1_WILD_RT]
#578153
01/10/10 10:41 AM
01/10/10 10:41 AM
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Joined: Aug 2008
Posts: 941
Texas, USA
ChrgrCuda
super stock
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super stock
Joined: Aug 2008
Posts: 941
Texas, USA
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I had this same problem, and had to find out the hard way about the bearing being upper and lower specific on my smallblock stroker. I felt like an idiot after pulling my hair out and finding this on my own.
68 Cuda Notchback [Email]10.86@120[/Email]
69 Charger R/T 440/505
2009 Challenger SRT8
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Re: Rotating assembly problem ...
[Re: rowin4]
#578154
01/10/10 11:04 AM
01/10/10 11:04 AM
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Joined: Dec 2009
Posts: 68
Detroit, MI
RawnDart
member
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member
Joined: Dec 2009
Posts: 68
Detroit, MI
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Quote:
You or the shop didn't put that rod on the piston backwards ? turning the rod around in the bore will make the straight side of the bearing to hit on the chamferd side of the crank ? 
That was my first thought, as well. I recently made that mistake with my 390 when I was assembling it.
I also remembered what a PITA spiro-locks are to remove without breaking anything.
I hope that it's something simple like that for you.
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Re: Rotating assembly problem ...
[Re: Bob_Coomer]
#578155
01/10/10 11:57 AM
01/10/10 11:57 AM
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Joined: Jul 2009
Posts: 413
Norway (old world)
Oyvind Mopar
mopar
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mopar
Joined: Jul 2009
Posts: 413
Norway (old world)
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I have been into similar problems where the rodcaps or the rod has been surfaced (as a part of reconditioning a rod, making the hole smaller before honing to size), and taken too much, and also not perpenticular to the sides. It all looks Ok untill you tighten the parts together, then the two halves are tilted when viewed from the side, and there will be no sideclearance. You can check this with some dye or marker on the whole sides of the rod and cap, then tighten, and turn the crank, pushing the rods to either side, and dismantle / check for the fit if even or not. Or, you can bolt the rod together outside the engine and put on a flat, and look for gap against the light, on either side. If it is inclined, I would demand a new rod from your machine shop; balanced to the same value as the others (if he got the records for them). Everytime such a job is done the rod gets shorter and you end up with a sheettt motor.  The quick and dirty fix is to file it flat again on the sides.  But the boltholes are no longer straight, and the bolt head surface or the threads will also be tilted and can fatigue the rodbolt in a shorter time.
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Re: Rotating assembly problem ...
[Re: Oyvind Mopar]
#578156
01/10/10 01:16 PM
01/10/10 01:16 PM
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Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer
OP
master
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OP
master
Joined: Nov 2003
Posts: 6,293
Rock Springs
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Thanks guys for the idea's....I wished it was as simple as the rod being installed backwards. These HXN bearings are super narrow, and the rod will touch the side of the crank well before the bearing does. When I plasti gauged this yesterday i made the piece long enough to extend from the radius to the center of the cap...Its not a radius problem. here is a bad picture, but you can see how narrow the bearing is and its location to the radius. 
[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
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Re: Rotating assembly problem ...
[Re: Bob_Coomer]
#578157
01/10/10 01:45 PM
01/10/10 01:45 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Bob, from looking at that pic it looks like the rod is over quite a bit on the wrist pin... is it hitting the piston .... hard to tell 
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Re: Rotating assembly problem ...
[Re: B G Racing]
#578162
01/10/10 05:47 PM
01/10/10 05:47 PM
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Joined: Jan 2003
Posts: 16,928
NC
440Jim
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,928
NC
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Quote:
It certainly doesn't look like a radius issue. 
From that pic, I agree. Assuming the rod cap is the same.
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Re: Rotating assembly problem ...
[Re: Oyvind Mopar]
#578166
01/10/10 07:15 PM
01/10/10 07:15 PM
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Joined: Dec 2009
Posts: 1,074
detroit, mi
POS Dakota
super stock
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super stock
Joined: Dec 2009
Posts: 1,074
detroit, mi
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Quote:
Could also be the rod is bent or twisted or both....
That's what it almost looks like from the picture. ALmost like the small end of the rod was finished at an angle.
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Re: Rotating assembly problem ...
[Re: B G Racing]
#578168
01/10/10 08:21 PM
01/10/10 08:21 PM
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Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer
OP
master
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OP
master
Joined: Nov 2003
Posts: 6,293
Rock Springs
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OK Just got home....I figured out the problem...Here is what I did... Before I took out the problem rod and piston I wiped the journal clean and threw on a piece of plasti gauge. The results showed some problems. It was clear that there is no interference with the radius or bearing. The results showed no crush of the plasti gauge near the fillet/radius, which was good. It showed taper though.. about .0015 clearance were the crush began, and the closer to the center of the journal the plasti gauge widened to show only .001 or so clearance. The # 3 rod shows .003 and floats good all the way across the same journal. So I continued to trouble shoot further.... The number 8 and 7 have very good side clearance and margins. So I decided to pull number the #8 piston and install it in the number 4 hole. I first pulled the cap back off #8 and wiped the surface clean. I then proceeded to plasti gauge this rod and cap assembly. Although I feel plasti gauge is a kind of a back yard shade tree mech deal..it can serve a purpose. I torqued it down and pulled the cap back of and viewed the results...It looked great..Nice even crush, I cut a pretty long piece and placed it diagonal across the journal cover most of the cap.. There was no sign of taper etc...Clearance was right at .003 which was what I wanted. I popped out the piston and rod assembly. Installed it in the #4 hole wiped the journal clean and added a piece of plasti gauge here..I torqued it down and pulled the cap.. Again it was a mirror image of before.... No taper and clean margins.. right on the money at .003 oil clearance....so... Being pretty anal. I pulled every cap, and plasti gauged every journal..they were perfect. I now know its in the rod. Looking at the rod cap, it has the same misalignment regarding the bearing offset as seen in BG part II thread. The wrist pin and small end floats nice and easy you can see both the wrist pin floating and turning on the rod, and in the piston working it back and forth. I went ahead and put the bearing back in the rod and torqued it too spec, I forgot too check the bearing number before I done this..Who knows it might have a miss matched bearing half's.. Sorry I didnt get no pictures..I felt on edge and wasnt in the picture taken mood...LOL... I am glad its not the crank.. I did get the cam degree'd..Im not sure how to install the cam so...Atleast I know the timing chain is correct..I first degree'd it on the 4° advance keyway...it cam in right at 105.5-106 ICL checking it twice....I then started from scratch and installed it at 0° (straight up) and degree'd it again...it came in at 109.5-110 ICL checking it twice again...I feel pretty confident that if I use the +2° advance key way..I probably wont degree it and check it, although I probably will LOL. well the kids have made me a B-day cake so.....
[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
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Re: Rotating assembly problem ...
[Re: Bob_Coomer]
#578172
01/10/10 08:59 PM
01/10/10 08:59 PM
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Joined: Jan 2003
Posts: 32,394
Quicktree
I Win
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I Win
Joined: Jan 2003
Posts: 32,394
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Quote:
Quote:
you better pull that crank and take it to get miced. and forget abot the plastic guage in this case.
I may end up doing just that Tony...
I will see what he has too say about this...He usually is very thorough..
I always have him set bearing clearance for me.. By doing this he torques up everything with the bearings installed and uses a dial bore gauge and mic..
I choose the bearing clearance..he does what it takes to make it to my specs...Never had a problem..
This way there aren't suppose to be any surprises during assembly.
When we first got the kit, the crank was on the high end of tolerance (big side)
Then the problem with new World Block the mains which required a line bore/hone to fix a tight main with taper...With the first set of bearings I was only going to have about .0025 on the rods...I wanted more, so he sent the original bearings back and exchanged them for the HXN, which added a extra thou of bearing clearance.
I plan to ask why this problem occurred, and if I had not check, and double check everything, and went on a run the engine it could have been bad...very bad...
He has been doing my machine work for almost 20 years. But I dont care if its been a 1000 years...I can not, and will not tolerate a error that could have destroyed a pretty high dollar engine...Fact is if this one breaks..there probably wont be any Do-Overs..so its gotta be right from the start..
take it somehwere for a second opinion  . don't take the chance.
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Re: Rotating assembly problem ...
[Re: rowin4]
#578174
01/10/10 10:24 PM
01/10/10 10:24 PM
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Joined: Jan 2003
Posts: 32,394
Quicktree
I Win
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I Win
Joined: Jan 2003
Posts: 32,394
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Quote:
Quote:
you better pull that crank and take it to get miced. and forget abot the plastic guage in this case.
What part of glad it wasn't the crank didn't you understand? 
after his last 2 posts I don't think he's sure and using the plasti guage is really not the best way to varify it don't you think? but hay if your sure run that thing. maybe you will warranty it
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Re: Rotating assembly problem ...
[Re: Quicktree]
#578176
01/10/10 10:38 PM
01/10/10 10:38 PM
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Joined: Jun 2005
Posts: 6,257
gulfport, ms, west mi
rowin4
master
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master
Joined: Jun 2005
Posts: 6,257
gulfport, ms, west mi
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Quote:
Quote:
Quote:
you better pull that crank and take it to get miced. and forget abot the plastic guage in this case.
What part of glad it wasn't the crank didn't you understand?
after his last 2 posts I don't think he's sure and using the plasti guage is really not the best way to varify it don't you think? but hay if your sure run that thing. maybe you will warranty it
I see nothing wrong with using plasigauge, it's been used for years, not the most accurate way , but it will show a problem as Bob found.
it's ok to butt heads, just don't do it with a butthead
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Re: Rotating assembly problem ...
[Re: rowin4]
#578177
01/10/10 10:41 PM
01/10/10 10:41 PM
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Joined: Jan 2003
Posts: 32,394
Quicktree
I Win
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I Win
Joined: Jan 2003
Posts: 32,394
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Quote:
Quote:
Quote:
Quote:
you better pull that crank and take it to get miced. and forget abot the plastic guage in this case.
What part of glad it wasn't the crank didn't you understand?
after his last 2 posts I don't think he's sure and using the plasti guage is really not the best way to varify it don't you think? but hay if your sure run that thing. maybe you will warranty it
I see nothing wrong with using plasigauge, it's been used for years, not the most accurate way , but it will show a problem as Bob found.
well  with that but I would still have it double checked if it were me
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Re: Rotating assembly problem ...
[Re: dodgeboy11]
#578180
01/10/10 11:17 PM
01/10/10 11:17 PM
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Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer
OP
master
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OP
master
Joined: Nov 2003
Posts: 6,293
Rock Springs
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Quote:
Give him the chance to figure out what happened, don't assume he screwed up and be glad you did your part of it. Remember, it's the assembler's job to catch things. If it had blown up it wouldn't have been your machinist's fault, it woulda been yours. Thankfully your meticulous nature caught it. But again, give your machinist the chance to figure out if it was a fault of his or if it's not.
Yep..
You gotta understand this guy..I swear before the Mopar Gods, he is the type that if he found a envelope of money at the entrance of a bank, he would promptly take it in side and turn it in.
I kinda agree with Tony..A second opinion wouldnt be a bad idea. But I know he wont lie, I plan to ask him how closely he looked at the rods. he wont lie.
Heck at this point, I wouldnt care if the crank needed turned to correct any problems..Yes it sucks, yes its more money, but hay..you know it will be right.
Plasti Gauge...
We amateur engine builders have used it. I try to keep it around. No it has no business in a performance engine assemblers hand.
Its only down fall is it just wont tell the whole story. It can read tapper to a point. It wont tell you if a rod is egg shaped. But in a questionable area it can really be useful. I knew that if the problem went away with the diff piston and rod..It pretty much eliminated the crank as the root cause.
We are only human. Anyone can make a mistake...Ever been gaping a ring and forget were you are on a particular ring gap cause you got side tracked a few seconds?
LOL....
[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
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Re: Rotating assembly problem ...
[Re: Bob_Coomer]
#578181
01/10/10 11:41 PM
01/10/10 11:41 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Plasti Gauge... We amateur engine builders have used it. I try to keep it around. No it has no business in a performance engine assemblers hand. Its only down fall is it just wont tell the whole story. It can read tapper to a point. It wont tell you if a rod is egg shaped. But in a questionable area it can really be useful. I knew that if the problem went away with the diff piston and rod..It pretty much eliminated the crank as the root cause. We are only human. Anyone can make a mistake...Ever been gaping a ring and forget were you are on a particular ring gap cause you got side tracked a few seconds? LOL....
Years ago when I used plastigauge I had a issue, I
measured it and it showed tight(for what I wanted)
so I took my rods to a shop and had them checked,
he measured them to be right where I wanted them...
found out that if the plastigauge is old it doesnt
work right.... bought some new plastigauge and it
showed correct.... since then I bought the proper
equipment to build engines with
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Re: Rotating assembly problem ...
[Re: Bob_Coomer]
#578183
01/11/10 02:03 AM
01/11/10 02:03 AM
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Joined: Feb 2007
Posts: 1,025
Las Vegas, NV
dodgeboy11
super stock
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super stock
Joined: Feb 2007
Posts: 1,025
Las Vegas, NV
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Quote:
Anyone can make a mistake...Ever been gaping a ring and forget were you are on a particular ring gap cause you got side tracked a few seconds?
LOL....
LoL, I have to start on the second ring due to the fact that it grinds so much faster than the top ring and if I start on the tops first, the very first second ring I do ends up a bit larger gapped than I woulda liked.. 
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Re: Rotating assembly problem ...
[Re: B G Racing]
#578184
01/11/10 07:36 AM
01/11/10 07:36 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
After each engine build we like to do a spot check of a least one rod and one main bearing with plastigage to check and confirm our clearence measurements during the build,surprizingly it come up very similar.At the construction co.on in chassis(frame)rebuilds on the big diesal Cat,Cummins,Detroits and etc,its the only way we can check the mains.These engines see over 300,000 miles and 7000 hours between rebuilds.
I'm surprised that you even have plastigauge in the
shop Bob
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Re: Rotating assembly problem ...
[Re: MR_P_BODY]
#578185
01/11/10 09:55 AM
01/11/10 09:55 AM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
Quote:
After each engine build we like to do a spot check of a least one rod and one main bearing with plastigage to check and confirm our clearence measurements during the build,surprizingly it come up very similar.At the construction co.on in chassis(frame)rebuilds on the big diesal Cat,Cummins,Detroits and etc,its the only way we can check the mains.These engines see over 300,000 miles and 7000 hours between rebuilds.
I'm surprised that you even have plastigauge in the
shop Bob
It's a great checking tool,keeps Chaz,Donny and Curt Jr on their toes.
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Re: Rotating assembly problem ...
[Re: Quicktree]
#578187
01/11/10 10:30 AM
01/11/10 10:30 AM
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Joined: Mar 2006
Posts: 9,847
MI, usa
dvw
master
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master
Joined: Mar 2006
Posts: 9,847
MI, usa
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Quote:
you better pull that crank and take it to get miced. and forget abot the plastic guage in this case.
I have used snap gauges,dial bore gauges and plastigauge in the past. Done correctly they will all show pretty close. Done incorrectly any of these methods can be inaccurate. My question in this case is this. If the lower bearing bore of the rod was not perpendicular to its centerline,how would this have been checked with a dial bore gauge? Yes the rod could be checked on a surface plate or with a checking fixture. With a "home build" careful assembly practices and plastigauge located a problem. I use any and all resources to locate problems during any build,engine ,trans,or chassis. Not trying to argue techniques here. Just trying to show that there are many resources available to locate a problem. I applaud Bob for careful assembly practices for catching a problem before it cost him. So many guys I see don't take the time and then can't understand why there stuff breaks or runs slower than there buddy's "exact same combo".
Doug
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Re: Rotating assembly problem ...
[Re: dvw]
#578188
01/11/10 10:37 AM
01/11/10 10:37 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Quote:
you better pull that crank and take it to get miced. and forget abot the plastic guage in this case.
I have used snap gauges,dial bore gauges and plastigauge in the past. Done correctly they will all show pretty close. Done incorrectly any of these methods can be inaccurate. My question in this case is this. If the lower bearing bore of the rod was not perpendicular to its centerline,how would this have been checked with a dial bore gauge? Yes the rod could be checked on a surface plate or with a checking fixture. With a "home build" careful assembly practices and plastigauge located a problem. I use any and all resources to locate problems during any build,engine ,trans,or chassis. Not trying to argue techniques here. Just trying to show that there are many resources available to locate a problem. I applaud Bob for careful assembly practices for catching a problem before it cost him. So many guys I see don't take the time and then can't understand why there stuff breaks or runs slower than there buddy's "exact same combo".
Doug
In this case if the rod is believed to be twisted
(just a IF) you could mount 2 rods on the journal
and try putting a wrist pin into both rods(1 pin
both rods)
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Re: Rotating assembly problem ...
[Re: Bob_Coomer]
#578189
01/11/10 10:40 AM
01/11/10 10:40 AM
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Joined: Jan 2003
Posts: 16,928
NC
440Jim
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,928
NC
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Quote:
OK
Just got home....I figured out the problem...
Looking at the rod cap, it has the same misalignment regarding the bearing offset as seen in BG part II thread.
It will be interesting to know if the problem was with the bearing shells, or the rod locating tang slot.
If it was the bearing, I don't see how the machinist would have caught that. Unless he marked each bearing with each rod when he checked clearances. If it was the rod tang slot location, he might have seen it, may not.
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Re: Rotating assembly problem ...
[Re: 440Jim]
#578190
01/11/10 11:09 AM
01/11/10 11:09 AM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
Quote:
OK
Just got home....I figured out the problem...
Looking at the rod cap, it has the same misalignment regarding the bearing offset as seen in BG part II thread.
It will be interesting to know if the problem was with the bearing shells, or the rod locating tang slot.
If it was the bearing, I don't see how the machinist would have caught that. Unless he marked each bearing with each rod when he checked clearances. If it was the rod tang slot location, he might have seen it, may not.
This is the case where plastigage is a savior.Everything may have miced up perfect and the rod may have incurred an issue after the fact like maybe got tweaked in the rod vise while torqueing the bolts or what ever.We have a similar issue years ago,it was so stupid it was hard to believe.When we installed and torqued the cap it almost locked up the engine.We did what Bob did and plastigaged it and found it was clamping on side tighter(no clearence)We checked the rod and there was no problems.By accident we found some tiny bumps on the back of the bearing shell that you cound hardly see with the naked eye.It was like and oxidation in the coating.We changed the insert and the problem went away. 
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Re: Rotating assembly problem ...
[Re: B G Racing]
#578192
01/11/10 12:10 PM
01/11/10 12:10 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
This may be a long shot,but I seen guys hit the crank counterweight while installing the piston and rod causing a little burr on the rod that will tighten up your rod to rod clearence.Like I said it's a long shot.
Like ya say... could be anything
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Re: Rotating assembly problem ...
[Re: Quicktree]
#578194
01/11/10 12:28 PM
01/11/10 12:28 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
with usinf plastigage for checking. didn't we argue about this with another builder a while back but once an issue is detected it's time to pull it out and do some serious checking.
No arguement,just different schools of thought. We can have 3 different people get different reading on a micrometer,Chaz has feather fingers,Curt Jr has vice grip and Donny is King Kong with all thumbs.Every tool has it's place.Some of us do some don't.As far as Bob's issue I would not be in a hurry to take the crank out till I pinpoint the exact problem.
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