Bellhousing alignment tool.

[Tiger]

Hi,

can someone please recomend a good bellhousing alignment tool.
I have found this one, http://www.precisionmeasure.com/fixt5.htm

is it ok?

thanks!

André

[dhardison]

André,

In my opinion you don't need a specialized tool. I easily aligned my bellhousing with just a standard (i.e. cheap) dial indicator and magnetic base. I'll admit that it took a couple minutes to get the base located correctly on the end of the crank, but after that it worked fine. Here are a couple examples:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=623

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=5646

HTH,
Dan

[Tiger]

How did you manage to center it on the crank ?
I mean, how did you get 100% sure that it was centered ?

thanks
André

[dhardison]

It doesn't have to be centered on the crank centerline. As long as the dial indicator magnetic base doesn't move while on the crank flange, the indicator plunger will rotate concentrically inside the bellhousing bore. I took measurements in four different locations (45 degrees apart).

Here's a good little article that I've saved over the years. Also, listed below that is a link to a Lakewood bellhousing alignment PDF doc.

Bellhousing Alignment
On any engine using a standard shift transmission, with or without an adapter, it is important to check the bellhousing locating bore location relative to the crankshaft. The potential for transmission failure or premature wear is so great, due to misalignment at this point, that no engine should be assembled without being checked. The checking procedure is quite simple. Correcting misalignment is not so simple but must be done to insure normal service from the transmission. A dial indicator is required, as well as a suitable means to mount this instrument on the engine crankshaft.

A dial indicator (right) is a device that has an arm or contact point, suitably connected to a pointer, that moves in front of a dial with markings on its face. These markings usually represent .001" each. The purpose of a dial indicator is to measure in thousandths of an inch that can be read directly on the dial of the indicator.

To check a bellhousing, mount it on the engine it's going to be used with, make sure there are no burrs or dirt on the block or bellhousing. All bellhousing to block bolts should be in and tight. Mount the dial indicator on the crankshaft of the engine using a suitable magnetic base attachment or mechanical clamping means. The contact point of the indicator should be touching the bore of the bellhousing. The indicator must be mounted rigidly enough so it does not move on its mounting to prevent false readings. Rotate the engine by hand with the spark plugs removed and observe the reading on the dial. Keep adjusting the dial assembly until the needle moves the least amount per rotation. When you have acheived the least amount of needle movement throught he 360 degree sweep of the indicator, this is your runout. You can then determine the direction it is offset by the movement of the needle.

The total number of thousandths misalignment of the bore relative to the crankshaft is read directly on the dial. Total runout should not exceed .007", with .010" being maximum. The greater the misalignment, the sooner transmission problems and failure will occur. A symptom of misalignment is unusual wear of the pilot bushing. We have checked stock Chevy bellhousings on engines that were out more than 1/32" (.032"). Some Ford one are reportedly worse. Anything over .010" runout must be corrected before the engine and bellhousing are put in service or you can count on pilot bushing, transmission, and clutch problems, followed by transmission failure. The simplest way to correct misalignment is to try another bellhousing or bellhousings. Machining the bellhousing is the best cure but offset dowel pins are simpler. Shims between the block and bellhousing will also work if you have the patience to use this method. Offset dowel pins are sometimes available from "speed shops."

Take a look at this doc by Lakewood (specifaclly page #4). You'll need the Adobe Acrobat Reader to view the PDF document. If you can't view it let me know and I'll copy/paste the alignment instructions for you.

http://www.danhardison.com/misc/lakewood.pdf

HTH,
Dan

[Tiger]

Dan,

thanks alot, I finally got it right.
I'll use a mag stand or just make up a holder myself
thanks for the PDF file as well.

André