Measure crank while in case half?

[jsoderbe]

Hi guys,

I bought a 3.2 Carrera engine from a wrecked car a few weeks ago. When dismantling it I found that it has been in a very serious accident, since the fan belt trolley, fly wheel, pressure plate and even the clutch has visible impact damage.

So, I want to make sure the crank is ok and not bent from the impact. I will partly disassemble the engine since I need to weld the left side case anyway. So, my question is if I can measure the crank while in the right case half (which I am leaving alone on the engine stand)? I plan to leave the P&C on the right side, but remove the cam house on that side too.

Any thoughts?


Regards,

Johan

[roblav]

No. I would question your path in continuing and consider selling it for parts.

[HawgRyder]

You would need to get the micrometer at 90deg to the crank to get a correct measurement.
With the crank still in the saddle...you can't do this.
As to the possibility of being bent....v-blocks and dial guages are the aproved way to check a crank...and that requires it to be out.
Bob

[jsoderbe]

So I cant measure for "wobbeling" in the case while turning it?

Roblav, please elaborate on why I shouldnt use it?


Regards

Johan

[HawgRyder]

If the crank is bent...you might detect a slight rubbing or tight spot in turning it.
You might even see it try to "climb" out of the bearing half.
I guess in a pinch...you could remove the center bearing half shell...and use a dial indicator on the crank as you turn it.
Bob

[crummasel]

If you are going that far, why dont you do a complete disassembly and make shure you can access properly everything what requires measuring especially in that case?
Further since the welding needs proper preparation and cleaning you will anyway be better off when completely disassembled.
Further 2: It may be preferable to torque the hollow case halves together again after cleaning and preparation as you probably want to preheat it prior to welding (at least i would do it) and that way you may reduce the risk of warping of the welded half. (saying that without knowing which welding process you will use and which portion you are going to weld)

[roblav]

When you said measure, I thought you meant measure the journals. If you have the engine that far apart, you may as well take the crank completely out and accurately measure the journals for wear. What I've found on these later engines is that the countershaft bearings wear before the crank journal bearings. So you might want to take the case apart to check those as well. It'll also be easier to weld the case half with it apart.

A method to measure if the crank is bent might be something like using a dial gauge and measure runout at the flywheel flange and nose flange while rotating the crank in a case half (or the complete case). Measure forward/aft runout as well as laterally. I believe the the spec books provide the tolerances. (This is what Bob suggests as well.)

My point earlier is that it sounds like the engine has some potentially very major issues, and it might be worth selling the pieces and obtain another short block (case/crank). I would not even consider buying a car that had a welded up case. Maybe others would...