Opinion on Broach Marks (Photo)

[Ken K.]

Look at the photo below, are the broach marks correct on this pad? They look a little too heavy to me. (Deep grooves) I didn't think they were that noticeable.
What's everyone's opinion? Thanks

[John L.]

Re: Opinion on Broach Marks (Photo)

Yep -- hey look a little odd maybe from a belt sander ??

[Terry F.]

Re: Opinion on Broach Marks (Photo)

They look nice to me. Just my humble opinion. I wish people would take pictures of the deck surface when the engine is being assembled. It would make it easier to see if the broach marks continue in a linear fashion across the deck surface. Does the block look good in regards to casting date, etc.

Terry

[Michael H.]

Re: Opinion on Broach Marks (Photo)

Totally incorrect in my opinion. Looks like just lines carved into the surface and they don't even run parallel to each other.

[Mark #28455]

several points

The broach marks shouldn't cross - they should always be parallel. That being said, big blocks typically have more pronounced marks than small blocks. In addition, when they start to corrode, the corrosion starts in the depths of the grooves - crevice corrosion - so it appears to highlight the marks.

If you were trying to reproduce the marks, one common way is to "texture" the pad with a hand held belt sander. Things to look for are that the parts of the deck that project beyond the heads on the sides of the block won't have the same grain pattern, that the pad which has been sanded now sits a few thousandths of an inch lower than the deck surface, and that if the sander moved, the lines won't all be parallel.

If you are looking at original blocks, not all have the same depth of marking as it also depends upon whether the factory cutters were sharp or dull - probably deeper marks with a sharper cutter.

A huge part of the puzzle is covered by the head. As noted above, you really want to see if the grain continues all down the deck surface too.

Good luck,
Mark

[mike mccagh]

Re: Opinion on Broach Marks (Photo)

nay, mike

[Tracy C.]

Re: Opinion on Broach Marks (Photo)

Ken,

Certainly consider myself a novice "broach mark / stamp" inspector, but these marks look over pronounced and do not appear to be aligned properly in relationship to one another.

I've yet to see factory marks that you could acually feel/detect by dragging a fingernail across. These appear to be that deep. Further more, I would think this surface texture would eventually lead to head gasket leakage it they did go completely across the top of the cylinder case.

tc

[Gary S.]

Re: Opinion on Broach Marks (Photo)

Right click on the photo, click on "save photo as" and save it to your My Pictures file. Then you are able to zoom in on these marks and see what everyone is talking about. The lines are not parallel and appear way too deap. Just my two cents though.
Gary

[Bill Farmer]

Re: Opinion on Broach Marks (Photo)

Here is the auction on ebay. There may be other indicators in the photos.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=4574384419&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

[Michael H.]

Matching Numbers

Well, I guess it does have "matching numbers". Just not likely the "original" matching numbers. (it's all in the wording) Next time we see that car, a few years down the road, it will likely have a completely different surface on the ID pad and all new numbers.

[Ken K.]

Re: Matching Numbers

Thanks for the input. I seen the car on ebay. I didn't think the engine pad looked correct. Thanks.

[Tracy C.]

at least it has "100 SHAKE DOWN" miles on it *NM*

[Rob A.]

Re: Opinion on Broach Marks (Photo)

I don't believe they are original broah marks. The last time I saw "broach marks" like these, was on an engine on which when the heads were removed, you could see the block was resurfaced in the stamp pad only, in order to restamp the numbers.