[gomickeygo]

Where to start with this thread...

I have built several stock performance Pontiac motor so I figured how hard can it be. Well...... Let me start by saying this is becoming a nightmare. I took my block to a local machine shop, very reputable place, to have them do the cylender hone and install camshaft bearings. I told them to take a look at the main for straightnes and lifters housing for any honing. I get the block back according to them it's good.
Camshaft bearings seemed okay until I placed my camshaft and noticed it was hard to put in. After putting it into place it would not turn. I thought that maybe the bearing didn't seat square. I took it back and they seemed to just ream out the bearing. Not happy but they say it normal?
Any takes on this? I will post pic.
I started checking bore hole measurements on my mains and they all check out at 2.999. I place my crank and just tighten the bolts enough to start torquing when I noticed the crank won't move. Again...... So remeaure everything I have .0036 high side to .0032 low side main bearing clearance. Also a .002 end play after some sanding on the thrust bearing. I noticed funky bearing wear so I figured a lined boring was in place. So I took it back and tell them the problem. They did a light bore hone and what seems a hone on the bearing to make up for bearing and diameter size. Is this possible ?
I want to measure but I'm so frustrated! I have no end play now and I have shaved off about .003 on the main bearing due to no end play in the beginning. How much can you remove?

My next question on crank end play. I seen videos and I seen everyone do it different. Are the measurement taken in resting position? Meaning if I push my crank back and remove the screw driver I should set it to zero. The move it forward remove screw driver and that end result should be my clearance?

Right now if I move it backwards with a screw driver i get to zeros out my indicator. If I move it forward with enough pressure I will get .006 but if I remove screw driver it set to zero. either direction. I can hear it move due to lube. It moves with pressure but the more pressure the higher the number vs a natural movement.

I know this sounds stupid but my buddy claims that's how it's done. Back in college years I learned it was the natural state of resting measurement.

Please help as I'm trying to build a street strip vehicle.

[Tom Vaught]

Checking crank thrust clearance is as you posted, use screwdriver move crank to rear of engine and set dial indicator to 0.0100, then put the screwdriver on the opposite side of a counter-weight and force the crank the opposite direction. Now you read for example 0.0040" so you have 0.006" of crankshaft end play.

I have seen tight camshaft bearings in some cases with a perfect installation. There are camshaft bearing tolerances in bearing manufacture process. Mike G probably has too.

As far as material removed from the thrust bearing surface, I would not be concerned about a .003" shaving. How did you remove the material. I have used a piece of flat glass or a precision flat surface plate with a 9" x 11" sheet of 1000 Grit Ultra Fine Silicon Carbide Sandpaper and some machine oil.

When you assemble an engine expect to "fine tune" a lot of the given parts in the process.

Tom V.

[JSPONT]

What bearings did you use? Do you have a dial bore gauge to measure the mains? Make sure you measure the rods too. I had to but 2 sets of mains to get the clearance I wanted. The rod bearings you can switch around, move the looser one to the tighter rod...
You are checking the crank with out the rear main seal in correct?
Was the crank new or cut? Did they check the decks for square?
Those blocks are rough finished and require a lot of machine work to get into specs. I am not knocking them, they have to do it like that. So many different crank,rod,and piston combos so they must be machined to what you have and your specs.

[Probird]

Torque one main bearing at a time and turn the crank before tightening the next one. Move to the next one and check crank rotation again until you find which main bearing is the culprit. Then carefully measure everything there to figure out problem. Did you have crank checked for straightness?

It's common to hone the cam bearings.

[gomickeygo]

New Ohio crank 4.50, 3.00 crank
Not sure if they checked for squareness
Using 113 m federal mogul

Found out that main 2 and 3 where not aligned right. one was to the right and the other was to the left. Fixed that problem. Just curious if honing bearing was okay. It's seem like it would sucks to change bearings in the future. I just got the block back and haven't measured anything yet.

[p4msi1]

On my IA2 I had to finish drilling out the oil passages to get pressure to the right side galley and up to the pressure port next to the distributor along with all the other standard machining processes. Long story short I pulled the motor 5 times to get it all straight. In the end when you mat the throttle, it will be worth it. Check check check

Steve

[taff2]

Main bearings shouldn't be honed that's for sure, how the hell would you be able to change a set of shells in the future? You would have to take the block back to a machine shop to get the new shells honed again! Find a different machine shop ffs!

[mysticmissle]

unfortunately those things are all part of building a performance motor. My IA2 the main bores were fine. I have heard of more than one that needed to be align honed.
I did have to chamfer the bearings to clear the crank shaft radius. I would check there for any shiny spots on the main bearings.
My cam tunnel was to spec but on a freshen up the new cam bearings might have been to the high side also, therfore the cam would not go it easily. Had to bring back to machine shop and they honed out the cam tunnel and put new bearings in and all was well.
All small issues, but the only way to find them is to diligently check and recheck everything. good luck

[mgarblik]

You have listed many concerns here about your engine build. Each item you listed could ruin your engine if you put it together and hope for the best. They all need to be addressed and corrected properly. 1. tight camshaft: Four things can make the camshaft turn tight. 1. the camshaft is bent, it should be checked on V blocks. 2 One or more journals are big, they can be measured with a micrometer. 3. Camshaft bearing is cocked in the bore, need to replace bearings. 4. Housing bores are rough or small, need slight hone operation to get to exact size. Next, you said the crankshaft turns tight. The same 4 types of issues can cause this. 1. A bent crankshaft, needs to be checked on V blocks 2. Main journals are too big and not enough fillet radius clearance, Crankshaft will need to be verified. 3. Main housing bores twisted, not in alignment, or not to size. (I have NEVER seen an IA II delivered with housing bores out of the tolerance range). They may not be perfect on spec, but always within acceptable tolerance. Crankshaft end play: The crank shaft MUST have free movement, back and forth. Place your dial on the crank nose and pry fore and aft. The crankshaft must have free movement of .004-.006"

Now, with all this being said, This is my recommendation. I don't know your engine builder and I will not bash any shop based on an internet post. But all the items you mentioned can be addressed by sanding, grinding, honing and otherwise modifying the bearings. THIS IS NOT THE CORRECT WAY TO FIX THESE PROBLEMS. The bearings are precision made, mass produced parts. If the block, crankshaft, and camshaft are all correct, they will fit the un-modified bearings and everything will turn easily, like butter. The camshaft, you should be able to grab the nose with your thumb and index finger and turn with little resistance. The crankshaft, you should be able to push on a counterweight with 1 finger and turn it. If these parts are tight, when you start the engine, they WILL make clearance by shedding bearing material and ruining your sizeable investment in this engine. If the engine shop's, "go to fix" for tight rotating parts is to make clearance in the bearings, I would be very concerned. This is not rocket science. It takes time to figure out what is wrong and a desire to make it right like it should be not just put a "band aid" on it and make it your problem.
I hate to say this but if they are mad at you now and think you are a PIA, you are better off taking the entire assembly to a well respected shop and start over. Best of luck to you.

[charlie66]

If you need a screw driver to get the full rang of end play something is wrong. You should be able to do this with ease by hand. Sounds to me it might be bearing interference with the radius of the crank shaft. I have a Ohio forged crank shaft in my motor and had to chamfer the rear main bearing because of this. I heard they make the radius larger for added strength .. You can check this by simply removing all the main caps and looking down on the block/crank and you will have a clear view of the parting ends of all your mains bearings to see how close they are to the radius of the crank shaft..

[chiefbigb]

I don't see where the type of block your using changes anything on how you build the engine. These blocks like the other brands race blocks need to have everything checked and rechecked. I have seen thrust bearings have a bit of play in the block on stock factory machined units. I check endplay with no thrust bearing then install it. If my measurement is much less both directions I don't think I'm running into the radius. Check it with no thrust cap and then with it. I seat the cap. Move the crank rearward then forward to center the bearings then torque from there. If you bought 3 blocks each one would probably be different in one way or another.

[gomickeygo]

what's upsetting is that I'm 750 in machine work and any machine shop around here charges 800 bucks for complete machine work. line boring to freeze plugs (includes balancing). The only thing done so far is balancing, cylinder honing since it was only .005, cam bearing being installed and a light line hone on the mains. The bearing have been honed to make up for the clearance. like someone motioned here, how am I going to change them in the future especially if I'm running close to .004 main bearing clearance? that means 40,000 miles from today Im going to change them and take it back to them?
I will be posting picture today if I can. it will help understand my frustrations. but for now I will be taking it back to them due to no end play.

[Rob B]

Another issue with the IA2 blocks is the lifter bores. If your using standard diameter lifters, your more than likely gonna need to hone the bores out to get them to fit. Paperwork with the block will even tell you this. You do not want to have the short block all assembled only to find when you try to put your lifters in that they are to tight and you have to pull it back apart.

[chiefbigb]

Welcome to the world of aftermarket parts. World products stuff dart and so on are not much different. You make the numbers right and it should be fine.

[gomickeygo]

Thanks guys! Guess i started and i have to keep on going.
Took the block back and their answer was u didnt mention anything about end play. Now the drama will begin... I specified i wanted the crank done right. Guess their right is different than mine.

[JSPONT]

Find another machine shop, do yourself a huge favor!!

[gomickeygo]

I got my block back but ran some quick measurement and I have to ask is the main spec at 3.195 to much specs call for 3.188-3.189

[Tom Vaught]

Was this deal done before or after you had the discussion with them?

That is a massive difference.

Tom V.

[gomickeygo]

After.

[gomickeygo]

Found out that the main where miss aligned. They had to hone it but they told me that it was a little over spec but within spec. Wtf? I asked what where the specks and they couldn't give me a number. I measured 3.1962 to 3.1956