Crankwalk?

[prove_it]

That sounds very logical. I get the point of priming the engine, but like in your case it actually hurt you. Be sure to really stare at the cranks thrust surface, it should be fine as the crank is harder that the bearing, but be sure.

Haven't heard much about the bearings you bought, will be nice to see how they work out.


How many times have the rod bolts and main cap bolts been torqued? Don't overlook those guys now that your doing it again.

 

[Coltsfan]

The crank is scored and groovy. Crank number two is at the machine shop for a polish and clean. Probably worth the $86 in hindsight. Keeping my fingers crossed, because I only have one more spare 6 bolt crank laying around the shop after this one.

The bolts have been torqued a (guessing) minimum of 4 times in the past. Once when it was built, again when someone else was in there and removed the balance shafts (maybe), two more times when I plastigauged it and assembled it, and who knows besides that. I'm leaving the head on for this procedure, so not dealing with head bolts at least.

I've assembled a bunch of engines in the past, and this is the first one I know of that isn't still running to this day, so I'm feeling a little befuddled. This is the first time I ever skipped having the crank looked at by a machine shop, and inevitably polished, but it looked so good I assumed it wasn't that important. Perhaps I put a nick in one of the thrust surfaces and simply overlooked it.

The mottled look of the rod bearings has me wondering high spots on the crank, low oil pressure, too much linear movement of the crank, or what?

Ps. Sorry for the horrible photo quality.

 

[prove_it]

Hard to see anything in that pic. I've rebuilt engines without having the crank polished before with no ill effects.

Also, I'd invest in new bolts. I don't think you wanna be kicking yourself for not doing it now.

 

[Coltsfan]

I'm going to take my chances with the bolts. Come to think of it, the rods were out of a virgin block, so the only one who has torqued those has been me and the factory.

Factory nitrided crank #2 polished and ready for action. Machinist said, "That is some hard material!"

 

[prove_it]

Do you REALLY want to take chances on bolts?

 

[Coltsfan]

Well how often are you supposed to replace them? I'm not building a monster.

 

[prove_it]

No, but constant torque stretches the bolt/studs and weakens the torque holding ability.

 

[iceman69510]

None of the 6 bolt bolts are torque stretch bolts, but they can certainly stretch over time. I can't remember off-hand if there is a measurement spec in the manual for these parts. I personally would not be too concerned about the main bolts, but would want to check the rod bolts if there is a spec. This is not as crucial as in a 7 bolt engine.

 

[prove_it]

Rod bolts worry me more. How many times have you heard the phrase "spun a rod bearing". I've far more spun rod bearings than main bearings.

 

[Coltsfan]

Well the rods were actually the original parts from the engine that's currently in my Colt, and I'm pretty sure they were only used once. A machine shop checked them and said they were good years ago, and they sat in a box ever since.

I have my lower gasket set, and new ball joints, and outer tie rods. Just waiting for all my main & rod bearings to show up Monday.

 

[prove_it]

I might still have a set of ARP factory rod bolts if your interested. BNIB. You'd have to have them pressed out and pressed in, but wouldn't be a bad idea for less than 100 bucks total.

PM if interested and I'll check my stash.

 

[FlyingEagle]

You have to resize the rods in that case. At least old school motors were that way. I am assuming they would at the very least have to be checked,
but I can almost guarantee a machinist will say they have to be resized when the bolts are changed out to non-factory types.

 

[thomcasey]

If you go to ARPS, you have to have the line honed to size once torqued to spec as they will be oblong as they compress

 

[Coltsfan]

Not pulling the pistons out of the bores. The rod bolts stay.

 

[MuffinMan7580]

I wouldn't worry about stretching the rod bolts either. Rod bolts are pretty resilient, and would be the last likely cause IMO to cause a spun rod bearing.

 

[Coltsfan]

Just an update on 631:
Crank #2 is polished, I have another new lower gasket "conversion" set as they call it, and the Sealed Power main and rod bearings arrived on Monday. All I need to get for it now is the time. It has the ultra plush, smooth running, noise free, helical cut oil pump in there. Maybe that's why it tore up the bearing. LOL
I'm also thinking that I should take a closer look at the oil filter housing to make sure it wasn't ported for some stupid reason.

 

[prove_it]

Why would you say some dumb reason? If it's ported that's great news. Stock wise they have issues with OVER pressurization. If it's ported, it's not going to lower the pressure to unsafe levels. The regulating spring controls that, if the spring is bad or been cut, then that's an issue, but not porting it.

 

[biglady112]

Ported filter housing are bad news. As well as cut springs. We do everything we can to get as much oil pressure as we can. Why that fad ever took of I don't know. We have never had over oiling issues in anything that we do. We have different needs as all of ours cars tend to live most of their time under heavy loads and high rpms.

 

[iceman69510]

Thus the difference. On a BSE car I have seen the resulting high cold oil pressure blow off an oil filter on a street car.

Pained me to do mine when I did, but I didn't like 110 psi either, as extremely high oil pressure can wash out bearings.

 

[prove_it]

A ported housing will still hold 90psi at redline, how is it bad news? That's like saying too big of a fuel return line will drop fuel pressure.

Cut regulator springs, yes, very bad. Ported housing, good, allows for proper oiling in the system. You CAN have too high of pressure without a BSE, pending on oil weight and bearing clearances.

BSE or not, a ported housing can only aid in proper oil pressure control.