pan rail cracks.

S

scooder

Well-known member
Whilst looking through a thread about a bad engine deal. It was mentioned that pan rail cracks in a flathead are fatal.

I've not had the misfortune to have to deal with these cracks yet. But there is a possible block in back that has a pan rail crack. I've sort of loosely thought in the past, drill each end and weld or, cold stitch with plugs, or drill each end vee it and cold epoxy fill or maybe even do a short (real short, couple of inches depth) fill with hard block or the like. But never really thought that this crack was fatal.
So is it fatal? Is it fixable? This particular engine would only be a fairly stock build for the street.
What do y'all think?
Thanks in advance,
Martin.
 
Problem as I understand it is, most if not all pan rail crack are cracked internaly also,That being said if you have the time go ahead and try it then pressure test the block, you may luck out.
If you do let us know what you find out GOOD or BAD.
 
I seen a few with a crack right in the middle of the pan rail about 3-4in. long. I figgered that it's been there for yr's and the gasket covers it. SO, what I've done is drill a small hole about 1/8 on each of the crack and take my small die grinder or Dremal tool with a small burr and V that crack a little and fill it with JB weld, let it set overnight and file it off flat, never had a problem. Knock on wood. Walt
 
I agree with Walt, I think it's not that Big a deal, unless I'm missing something here. Kind of interested in why some say it's fatal?
If I get into this engine and build him up I'll do a photo build on the repair, and pressure test and if it looks like a fix, I'll flick it in the truck and put some miles on him. And report good and bad, hopefully just good. Be nice to report that these cracked engines don't need to be scrapped.
Martin.
 
scooder said:
Whilst looking through a thread about a bad engine deal. It was mentioned that pan rail cracks in a flathead are fatal.

I've not had the misfortune to have to deal with these cracks yet. But there is a possible block in back that has a pan rail crack. I've sort of loosely thought in the past, drill each end and weld or, cold stitch with plugs, or drill each end vee it and cold epoxy fill or maybe even do a short (real short, couple of inches depth) fill with hard block or the like. But never really thought that this crack was fatal.
So is it fatal? Is it fixable? This particular engine would only be a fairly stock build for the street.
What do y'all think?
Thanks in advance,
Martin.
Click to expand...

Hi Martin, over the years we've seen tons (maybe literally) of blocks with those specific cracks. Almost all had cracks in other locations as well as the obvious ones in the pan rail area!

When you are operating as a business and rebuilding any Flathead you can not take a chance on a repair if it's not 100% "guaranteeable". Most times it isn't. You have to able to stand behind every unit you build and be confident about sending it to someone.

As an individual who may want to try his or her own repair it becomes a different game. If it fails there's no one to blame and any monies/labor "wasted" are on them.

In the photos below you can see how the cracks run, they didn't stay on the gasket surfaces but went up the interior walls. That's both sides of the casting. One made it clean back to the bellhousing area?

Thanks, Gary in N.Y.

P.S. Here's a couple shots of "pan-rail-cracks", this particular block has other severe cracks in numerous spots! It has become our "test-block" for fitting purposes, mainly for checking large-bore stroker clearances. It has 8 different bore sizes to accommodate most of the available piston o'sizes.
 

Attachments

  • Flathead Block Cracks A.JPG
    Flathead Block Cracks A.JPG
    72.2 KB · Views: 237
  • Flathead Block Cracks B.JPG
    Flathead Block Cracks B.JPG
    67.9 KB · Views: 205
I'd call that a little more than a pan rail crack. I've seen plenty of these cracks and junked all the bocks. I always mag them but you can see those cracks with out glasses. Walt
 
Gary, they be some cracks for sure! If mine had those I wouldn't consider repairing them. It'd be a good candidate for port experiments. The crack mine has is only 'bout 2" max, and far from any main journal area. And this engine would remain my engine.
Thanks for your input.
Martin.
 
Cheers Mr coupe, forgot Mart had done this, thanks for reminding me.
So is the consensus as follows? Something like Marts one and the type me and Walt pertained to are fixable, with a couple of options. And something like the pic Gary has, is terminal. Seems fair.
If the crack migrates inside or outside or both a little, 1" or so, still not terminal. I feel if the crack is inside and is heading off to the main journal area's,then it probably should be called no good.
Think street very low stress engine here. Not a 300+ cube with blower.
Thanks again for imput.
Martin.
 
Let me add this, if you are talking only these "smaller, fairly contained" cracks, besides the repair, I would recommend a "fill" inside the pan rails. I would fill it up to the point where it just slightly covers the pan bolt bosses!

This would give a little extra insurance against leaking. It would have to be fairly clean in there!

I would use either Moroso's "Engine Block Filler" or their "Ceramic Engine Seal", both work well. This is only for "back-up", I would want the repair to hold on it's own.

Thanks, Gary in N.Y.

P.S. Using these "repairable" cracks as an example, and having a shop do the entire build, where would you "draw a line in the sand" when building a unit for a customer. Assuming the builder does the actual repair, at what point is it NOT his responsiblity?? What if you shell out $6000.00 (this is a nominal "low" price on a good build) and the repair just happens to fail??? Not necessarily immediately, maybe a month or two down the road?? Exactly who's fault would it be AND how would you expect it to be resolved?? Just curious! I'd have to think even if the issues/risks are entirely covered by both parties before the build starts AND both agree to go forward, there's going to be someone real unhappy if it don't last! When we deliver a unit I have no room to be only 99.9% sure it will survive, it's GOT to be 100% or we pass on the build.
 
When you are talking $6000 and up OF MY MONEY for an engine, I would want nothing questionable. Speaking here of blocks, about $500 for a good core seems prudent. I'm sure many factors, such as sentimental value, will arise to complicate the issue.
 
Hi Mart.

Yeah, if it's a simple one like mine, like Walt said, they are a simple fix. I do have another block that has one like Gosfast's motor, but even worse, it goes right across the centre web. I decided that was beyond my skill set and it's sitting outside now. I can't quite get around to chucking it though.

Good luck with it.

Mart.
 
I have a 8BA Engine with pan rail cracks, bought it for the parts.
But ive been thinking to brazing the cracks shut, since think the thing is to stop a leak. And I guess there will not be much force going thru that part of the engine.
 
Where i come from, no engine blocks are to be found, hence i do not own one (maybe one day, and if i do, chances are it will be cracked) i believe in fixing them, "But nobody else fixes them", well too bad for everyone else then, because i believe in using science to create technology to overcome problems.

Mr 42 said:
I have a 8BA Engine with pan rail cracks, bought it for the parts.
But ive been thinking to brazing the cracks shut, since think the thing is to stop a leak. And I guess there will not be much force going thru that part of the engine.
Click to expand...

Yes please try that. Report back how well it works for future assessment.
 
Hey dumb person. Sorry, but I can't help from asking. Where in South Pacific Islands are you (which islands)? Do you not have many old Fords cruising round out there? Apologies scooder for going off-topic for a moment.

Miles. (NZ)
 
You must log in or register to reply here.
Back
Top