Tear down diagnosis

[assault187]

Alright fella's I pulled the motor this evening and all I have left to do is pull the crank and check the bearings for good measure. I found the obvious heavy coating of oil on the pistons and slight scoring on the piston walls but the cylinders look good and the cross hatching is still very visable. I was SUPRISED what I found when I removed the oil pan! Now when I had this motor built by the shop I had supplied EAGLE H-BEAM rods that I had picked up from a local shop for $325 or so. Well when I removed the oil pan I noticed the rod bolts did not have ARP inprinted in them,....I wiped my eyes and looked closer and wiped the oil off the surface to find it says CROWER. I thought no way...Popped the piston and rod out of the #1 and found I have CROWER I-BEAM rods! Now I'm thinking this block wasnt meant to be mine so I'm going to check the cylinder bore, piston size and make sure all that is well. I took some pictures that I plan on posting for my progress.

 

[assault187]

I contacted someone who works at she shop that assembled the block, He said they didnt even carry Crower rods untill recently so they must have givin me someone elses block.

I want to check the bore size on the block to make sure I have the proper size rings and pistons. What would be the measurement for a block bored .020 over and 30 over or even the stock bore size for the cylinder walls?

EDIT:

Stock bore size: 85MM
.020 over: 85.5MM
.030 over: 85.75MM
.040 over: 86MM

correct?

 

[olmytsi]

Damn Nick. Are you even sure of the pistons you have now?

 

[assault187]

Damn Nick. Are you even sure of the pistons you have now?

The pistons are Ross as they should be, They have ROSS stamped into the inside of the piston.

 

[blcknspo0ln]

1 inch / 25.4 mm = .039 inch/mm x .5mm = .020 inches
.75 = .030
1 = .040

Ross pistons .020 over for 27psi+

.0055 PTW clearance
Top rings @ .019 gap
Bottom rings @ .023 gap
Mains @ .002 clearance
Rods @.002 clearance

Does this look good? These are the specs I plan on going by when I re-do everything and for reference when checking whats in there already

These are actually very similar to the specs I was looking to get at the machine shop. Ideally I wanted .0055, .019, .022,.002,.002 in the same order, but ended up with a slight variance, but still acceptable. These were for my ross 8.3:1 and eagle H-beams.

 

[assault187]

I removed the rings from the pistons and checked the gap in the cylinder walls, Top and bottom rings for each piston were gapped pretty big. My feeler gauge only went up to .025 and they were all larger, when I got up to .027 (by combining feelers) I left it at that knowing they were too big....

I did notice some scoring on the crank which I could feel with my finger nail, Is this acceptable? It seems to be the worst on cyl#3. The rod bearings looked OK to me, and the crank has been polished once before. I'll post pictures tomorrow after ESCO.

 

[delta448]

I removed the rings from the pistons and checked the gap in the cylinder walls, Top and bottom rings for each piston were gapped pretty big. My feeler gauge only went up to .025 and they were all larger, when I got up to .027 (by combining feelers) I left it at that knowing they were too big....

That's where the oil went through. Did you ever figure out the piston to bore clearance? I'm just curious what it was. I'll bet you got the right block and just the wrong rods and pistons, nobody would intentionally gap a compression ring that wide.

I did notice some scoring on the crank which I could feel with my finger nail, Is this acceptable? It seems to be the worst on cyl#3. The rod bearings looked OK to me, and the crank has been polished once before. I'll post pictures tomorrow after ESCO.

If you can feel it with a fingernail, it's too rough.
I'm looking forward to any and all pics.

 

[assault187]

That's where the oil went through. Did you ever figure out the piston to bore clearance? I'm just curious what it was. I'll bet you got the right block and just the wrong rods and pistons, nobody would intentionally gap a compression ring that wide.

If you can feel it with a fingernail, it's too rough.
I'm looking forward to any and all pics.

As for the piston to wall clearance, Im not sure how to get an accurate measurement...Could someone fill me in on how to do this correctly as I have never done it before...

I have lots of pics, They should be up tomorrow evening.

 

[delta448]

The cheapest way to measure PTW clearance is using a set of ribbon style feeler gauges. They are about 12" long and usually come in sets of 0.0005", 0.0010", 0.0015", 0.0020", etc. To use them, place a ribbon and the piston in the bore, pulling gently on the ribbon. When you find the ribbon that requires about a 5-8 lbs pull to remove with a slow drag, you've found PTW. If you're not sure what 5-8 lbs feels like, use a set of fishing scales.

However a much better way to do it is to use a caliper or external mikes on the piston and a dial bore gauge or internal mike in the cylinder and measure the difference directly by simple subtraction.

 

[SlowSpyder]

I use 5w30 full synthetic, and I always let the car idle up to normal temp before driving it. Also keep in mind I am also running the forward facing oil filter housing so there is no oil pressure lost to an oil cooler or anything.

did you use synthetic oil to break in the new motor??

 

[assault187]

did you use synthetic oil to break in the new motor??

I used conventional oil for break in for about 1500-2000 miles then switched over

 

[assault187]

The cheapest way to measure PTW clearance is using a set of ribbon style feeler gauges. They are about 12" long and usually come in sets of 0.0005", 0.0010", 0.0015", 0.0020", etc. To use them, place a ribbon and the piston in the bore, pulling gently on the ribbon. When you find the ribbon that requires about a 5-8 lbs pull to remove with a slow drag, you've found PTW. If you're not sure what 5-8 lbs feels like, use a set of fishing scales.

However a much better way to do it is to use a caliper or external mikes on the piston and a dial bore gauge or internal mike in the cylinder and measure the difference directly by simple subtraction.

Ahh...good idea! I recently bought a digital micrometer too.




EDIT: The website I use to host my pictures is not working at the moment, I'll try again tomorrow

 

[assault187]

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slight scoring on the piston

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I cleaned the piston and this is what remained...The Punisher mark

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Suprise! Crower Rods

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scoring on crank journals. I guess I should replace the crank?


I'll snap some pics of the ring gap as well

 

[mach4g63t]

I don't think I saw this anywhere in the thread, but check the block to see if it's warped/uneven. I'm assuming since you've swapped 3 heads on it, all of them were freshly decked? Check the motor.

You can probably just have that crank polished, depending how badly it is scored. If you can't really feel it with your fingers, just have a machine shop micro polish it.

 

[assault187]

I don't think I saw this anywhere in the thread, but check the block to see if it's warped/uneven. I'm assuming since you've swapped 3 heads on it, all of them were freshly decked? Check the motor.

You can probably just have that crank polished, depending how badly it is scored. If you can't really feel it with your fingers, just have a machine shop micro polish it.

The reason 3 head have been on the car.... 1st head was a 7 bolt 2g head, 2nd head was a 6 bolt head, 3rd head was a built 6 bolt head. They were not really swapped out to diagnose anything, it was just part of my upgrade path. BTW if you missed the 2nd page here, I am checking the motor

As for the crank (if its mine) it has been cut once already and not recomended to be cut again. To my knowledge, if you can feel the scoring with your finger nail they are too deep to polish out.

 

[blcknspo0ln]

I would definitely go and find a virgin uncut crank, going .010" is up to you, but having known its been cut before leaves me very wary.

 

[assault187]

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Thats a .035 gap...All rings were simalar!

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piston bore size

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Cylinder bore size

So the PTW clearance is .004. Im sure I'll get that extra .001 to equal .005 PTW when the cylinders are clean considering you have that slight ring at the top of the cylinder

 

[assault187]

I found a replacement crank, Will it be necessary to re-balance my rotating assembly with the replacement stock crank?

 

[delta448]

Yes. Or at least I would.
Imbalance is bad for the entire engine, but will destroy the bearings the quickest.
I would get the balance done with the flywheel included. Invest in a good damper if you haven't already, but don't include it during balancing.

Also, your PTW isn't really accurate if you're measuring the cylinder above the ring travel where the ridge is. That could be as much as 0.010" more, depending on the mileage, oiling and load level the engine has seen.

 

[assault187]

Yes. Or at least I would.
Imbalance is bad for the entire engine, but will destroy the bearings the quickest.
I would get the balance done with the flywheel included. Invest in a good damper if you haven't already, but don't include it during balancing.

Also, your PTW isn't really accurate if you're measuring the cylinder above the ring travel where the ridge is. That could be as much as 0.010" more, depending on the mileage, oiling and load level the engine has seen.

I'll get the assembly balanced then for good measure.

As for the PTW, I did take that into mind when doing it but I didnt think it would be that durastic of a change for such low mileage. Since I'll be bringing the rotating assembly to the machine shop, I'll bring the block down as well to get an accurate PTW clearance value and to have the block decked and cleaned.

 

[assault187]

Im looking to pick up MAIN and ROD bearings....


ACL tri-metal or Mitsu OEM?

 

[delta448]

In my opinion, ACL. But I'm sure there will be others who post an opposite opinion.

Mitsu bearings are great quality but weren't designed with the kind of power you'll be going after with the HX-40 in mind. IMO ACL Race bearings are about the best available.

 

[mach4g63t]

Yep, ACL's.