Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 06-14-2020, 04:03 AM   #1
Sckxyss
Junior Member
 
Join Date: Apr 2020
Location: Lachute QC Canada
Posts: 26
Default Rusted block, repairable?

Hello.
I just got a B engine I know who need to be sleeved but what about this pitting on the valve seats.

Do I need to worry about this?

Regards.
Attached Images
File Type: jpg 20200614_043832_resized.jpg (39.6 KB, 373 views)
Sckxyss is offline   Reply With Quote
Old 06-14-2020, 05:19 AM   #2
chrs1961815
Senior Member
 
chrs1961815's Avatar
 
Join Date: Jul 2018
Location: Spring Grove, Illinois
Posts: 1,371
Default Re: Rusted block, repairable?

I would be concerned about the valves not sealing with that degree of pitting. You can get away with pitting on the head gasket surface because of the crush, low compression, and the spray many use.

Since the block needs to be sleeved, it has probably been decked several times which means it may or may not be a good idea to deck the block again to get rid of the pitting.

Also, B engines are notorious for cracks, so be sure to give it a thorough inspection.
__________________
"The more things change, the more they stay the same."
chrs1961815 is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 06-14-2020, 09:14 AM   #3
midgetracer
Senior Member
 
midgetracer's Avatar
 
Join Date: May 2010
Location: Bismarck ND
Posts: 1,189
Default Re: Rusted block, repairable?

usually pits like that indicate a crack somewhere in that cylinder. You can install new valve seats to solve the pitting, however I would magnaflux the block to see if there is a crack in that cylinder area.
midgetracer is offline   Reply With Quote
Old 06-14-2020, 09:39 AM   #4
rotorwrench
Senior Member
 
rotorwrench's Avatar
 
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 16,367
Default Re: Rusted block, repairable?

I'm not sure how far a person can go when shaving the deck but it would likely need a good skim of the surface to insure good sealing. Valve pockets can be counter bored to install replaceable seats. The more machine work done, the higher the cost.
rotorwrench is offline   Reply With Quote
Old 06-14-2020, 10:01 AM   #5
ronn
Senior Member
 
Join Date: Feb 2011
Location: NNNNNNNNJJJJJJJJJJ
Posts: 6,758
Default Re: Rusted block, repairable?

get another block..........
ronn is offline   Reply With Quote
Old 06-14-2020, 10:15 AM   #6
Kurt in NJ
Senior Member
 
Kurt in NJ's Avatar
 
Join Date: May 2010
Location: on the Littlefield
Posts: 6,140
Default Re: Rusted block, repairable?

Sponsored Links (Register now to hide all advertisements)
Why do you say it needs sleeves?
with that rust there is a good chance that there is a crack through the valve seat toward the cylinder ---this crack is common with "B" blocks
If not cracked a replaced valve seat will fix the rust , the other pitting in the combustion chamber area won't matter as long as it doesn't go under the gasket surface
Kurt in NJ is offline   Reply With Quote
Old 06-14-2020, 10:33 AM   #7
Jack Shaft
BANNED
 
Join Date: Dec 2019
Posts: 1,196
Default Re: Rusted block, repairable?



this is rusty .Im actually going to try and save it. B blocks have varying casting thicknesses,they are way more prone to cracking and machining issues than an A block.Some B blocks are thick in the valve seat and pocket area,some are thin.I have one with 21 crack pins in the deck..step into the machine shop lightly,magnaflux and sonic test prior to committing to it
Jack Shaft is offline   Reply With Quote
Old 06-14-2020, 11:57 AM   #8
Jim Brierley
Senior Member
 
Join Date: Jun 2010
Location: Temecula, CA
Posts: 4,066
Default Re: Rusted block, repairable?

A/B blocks can be safely bored to 4" (.125" oversize), many were bored to 4.062" by racers back in the day. Your rust indicates water entered from somewhere, maybe just the head gasket?
Jim Brierley is offline   Reply With Quote
Old 06-14-2020, 11:54 PM   #9
40 Deluxe
Senior Member
 
Join Date: May 2010
Location: now Kuna, Idaho
Posts: 3,774
Default Re: Rusted block, repairable?

Do you know any history of this engine? Was it stored outside or in a leaky shed for years? You should be able to find the blueprint dimension for the distance from the pan rail to the deck surface, which will tell you how much the block has been resurfaced, if any.
How deep are the pits in the cylinder wall? It may clean up without sleeving. B blocks no longer grow on trees so if there are no fatal cracks either you (or the next owner) should save it.
40 Deluxe is offline   Reply With Quote
Old 06-15-2020, 12:06 AM   #10
Terry Burtz, Calif
Senior Member
 
Join Date: May 2010
Location: Campbell,CA, USA
Posts: 313
Default Re: Rusted block, repairable?

Drawing A-6015 specifies that the dimension from pan rail to the top of the cylinder block is 11.500/11.505 inches.
Terry Burtz, Calif is offline   Reply With Quote
Old 06-15-2020, 07:22 AM   #11
Sckxyss
Junior Member
 
Join Date: Apr 2020
Location: Lachute QC Canada
Posts: 26
Default Re: Rusted block, repairable?

Thanks for all your replies. What's the issue of shaving the deck too much, too little material left or piston clearance. Obviously it stay outside for a long time and the pitting will compromise sealing, two cylinders are pitted too that's why it needed to be sleeved. A crack have been fixed already and the block suppose to have been pressure tested.
I don't think it have been shaved before, you can see a "M" stamped on the surface at the top of the upper cylinder and it's still very clear. I will try to measure the pitting but I will remove the remaining rust with electrolysis before.
Best regards.

Last edited by Sckxyss; 06-15-2020 at 07:31 AM.
Sckxyss is offline   Reply With Quote
Old 06-15-2020, 07:40 AM   #12
WHN
Senior Member
 
Join Date: Mar 2017
Location: Connecticut Shoreline
Posts: 1,815
Default Re: Rusted block, repairable?

If you decide not to use, I would give it to someone else to try an save.

As mention earlier, there just aren’t a lot around.

Your trash is my treasure.

Enjoy.
WHN is offline   Reply With Quote
Old 06-15-2020, 08:04 AM   #13
chrs1961815
Senior Member
 
chrs1961815's Avatar
 
Join Date: Jul 2018
Location: Spring Grove, Illinois
Posts: 1,371
Default Re: Rusted block, repairable?

Yes the more shaving you do the more piston ping becomes a problem as they get closer to the head. If it has not been shaved before it is worth doing it.
__________________
"The more things change, the more they stay the same."
chrs1961815 is offline   Reply With Quote
Old 06-15-2020, 09:06 AM   #14
BRENT in 10-uh-C
Senior Member
 
BRENT in 10-uh-C's Avatar
 
Join Date: May 2010
Location: Eastern Tennessee
Posts: 11,484
Default Re: Rusted block, repairable?

Quote:
Originally Posted by Sckxyss View Post
Thanks for all your replies. What's the issue of shaving the deck too much, too little material left or piston clearance. Obviously it stay outside for a long time and the pitting will compromise sealing, two cylinders are pitted too that's why it needed to be sleeved. A crack have been fixed already and the block suppose to have been pressure tested.
I don't think it have been shaved before, you can see a "M" stamped on the surface at the top of the upper cylinder and it's still very clear. I will try to measure the pitting but I will remove the remaining rust with electrolysis before.
Best regards.

If I were in your shoes, I would find the best antique engine rebuilder in your area.

If it were in my shop, I would treat it as a rare or 'one-off' engine where replacement was not an option. Terry is correct on the pan to deck measurement however if we did not have a measurement (-and I would do this anyway on this particular block) I would use a sonic tester and map out the areas that are pitted to know the thickness in all the areas. If I recall correctly, the Ford print called for 0.375" deck thickness, and as long as it measures 0.350" or greater after a surfacing, you are probably OK. If not, then I would use a TIG and something like Muggy Weld 77 to fill the pits. Preheat the block, fill the larger pits, stress-relieve and resurface. Not going to be cheap, but the repair would be solid.
__________________
.

BRENT in 10-uh-C
.
www.model-a-ford.com
...(...Finally Updated!! )

.
BRENT in 10-uh-C is offline   Reply With Quote
Old 06-15-2020, 10:50 AM   #15
Jim Brierley
Senior Member
 
Join Date: Jun 2010
Location: Temecula, CA
Posts: 4,066
Default Re: Rusted block, repairable?

What size is your bore now? It will likely clean up with another .030", and not need sleeving. If there is no sleeve, it won't cause any problems.
Jim Brierley is offline   Reply With Quote
Old 06-15-2020, 04:25 PM   #16
Dave in MN
Senior Member
 
Dave in MN's Avatar
 
Join Date: May 2010
Location: Jordan, MN
Posts: 1,410
Default Re: Rusted block, repairable?

Model "B" engines can quickly become "money pits" as the more you do to them the more they seem to require.

It is difficult to give an assessment based on only a partial view of two of the 4 cylinders.
I would guess you are showing us the worst area of the block. If you still have close to 11.5" total block height, a light decking of the top, just enough, to provide a good surface for the gasket would be required. Don't try to eliminate all the pitting in the combustion chamber as it is not necessary. The bad pitting in the valve area could be worked around by installing oversize valves and with the light decking you should be good. The increased diameter seat cut would get you to good metal. If it were my block, I would use larger valves, keeping them set high, before risking cutting in hardened seats, or cutting deep for standard size valves.

I used this method on two "B" blocks with bad pitting as you show. They both are not high HP engines and are still in service.

To counter the previous experience, I also had a badly rusted "B" I rebuilt for myself. I decked both the top and manifold surfaces to fully clean it up. I also needed to install three helicoils adjacent to the decked manifold surface. (More lost metal!) It failed at about 15,000 miles. The removed metal from the manifold surface weakened the block, enough so that it cracked at two of the head bolt areas with helicoils into the adjacent water jacket openings. I should have left the manifold surface alone as the gasket would have sealed it. Lesson learned, the hard way about removing too much metal and about money pits!
Good Day!

Last edited by Dave in MN; 06-16-2020 at 03:50 PM.
Dave in MN is offline   Reply With Quote
Old 06-15-2020, 09:31 PM   #17
Sckxyss
Junior Member
 
Join Date: Apr 2020
Location: Lachute QC Canada
Posts: 26
Default Re: Rusted block, repairable?

I don't have the perfect tool to measure the damage but shaving .030" will remove most of the pitting for a proper gasket seating and I have 11.5 of total block height. My idea was to install a high compression head and the Brumfield 5.2 have extra material to be shaved to 5.9 so no problem for clearance I think. The bore is actually 3.890" but the pitting on one cylinder is deep, probably .050" The engine came with the sleeves and pistons anyway. My main concern is the metal remaining around the exhaust valve and port, approximatively .300" at the thinnest point. The lobes on the camshaft are pitted also.
Attached Images
File Type: jpg 20200615_215839_resized.jpg (56.8 KB, 83 views)
Sckxyss is offline   Reply With Quote
Old 07-13-2020, 07:52 PM   #18
Sckxyss
Junior Member
 
Join Date: Apr 2020
Location: Lachute QC Canada
Posts: 26
Default Re: Rusted block, repairable?

And this corrosion on the exhaust port. It will leak?
Attached Images
File Type: jpg 0-12.jpg (62.6 KB, 116 views)
Sckxyss is offline   Reply With Quote
Old 07-13-2020, 11:09 PM   #19
Jack Shaft
BANNED
 
Join Date: Dec 2019
Posts: 1,196
Default Re: Rusted block, repairable?

B block casting variations are common,some decks are thick,others are thin.Sonic testing is very touchy and as a result isnt reliable unless performed correctly which is very time consuming.I have a B block with 21 crack pins in the deck.Most of the pitting in the combustion chamber is ok,your concern is the fire ring area of the headgasket.Way more reliable to pressurize a late 31 A block than to deal with a B block
Jack Shaft is offline   Reply With Quote
Old 07-14-2020, 03:56 AM   #20
chrs1961815
Senior Member
 
chrs1961815's Avatar
 
Join Date: Jul 2018
Location: Spring Grove, Illinois
Posts: 1,371
Default Re: Rusted block, repairable?

At least on Model A engines, pitting is very forgiveable. I was able to spray copper sealant on my head and exhaust gaskets and have never had a problem with pitting there. Of course the pitting was not extreme and I cleaned the surfaces with a sander.
__________________
"The more things change, the more they stay the same."
chrs1961815 is offline   Reply With Quote
Old 08-27-2020, 04:51 PM   #21
Sckxyss
Junior Member
 
Join Date: Apr 2020
Location: Lachute QC Canada
Posts: 26
Default Re: Rusted block, repairable?

Quote:
Originally Posted by Jack Shaft View Post


this is rusty .Im actually going to try and save it. B blocks have varying casting thicknesses,they are way more prone to cracking and machining issues than an A block.Some B blocks are thick in the valve seat and pocket area,some are thin.I have one with 21 crack pins in the deck..step into the machine shop lightly,magnaflux and sonic test prior to committing to it

Good luck to save it, i found an other rusted block for cheap and everything was seized. After two weeks in the electrolysis bath i was able to move the camshaft a little bit but i broke the block trying to unseized the tappets. It is thin at this place.
Sckxyss is offline   Reply With Quote
Old 08-27-2020, 05:41 PM   #22
Jack Shaft
BANNED
 
Join Date: Dec 2019
Posts: 1,196
Default Re: Rusted block, repairable?

Thanks,got two 8BA'S and two 59AB'S cheap..Ive got time on this one,if I can't save the block no big deal.

Like flathead V8's, B engines are good if you get a good one. In my opinion A blocks are way better,Ford had a low casting rejection rate with the A block (96% casting rejection rate in '32 with the V8,it would have ran anyone else broke). Find a late 31 A block,they are the best,build with confidence, odds are you won't get hurt by a crack.
Jack Shaft is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 08-27-2020, 06:26 PM   #23
Sckxyss
Junior Member
 
Join Date: Apr 2020
Location: Lachute QC Canada
Posts: 26
Default Re: Rusted block, repairable?

The worst is i trade this corroded B block for a working A engine. The smart guy event put grease on the camshaft so i will not see it was pitted. I have some A blocks and many parts to build a good one anyway. Regards.

Last edited by Sckxyss; 08-27-2020 at 06:32 PM.
Sckxyss is offline   Reply With Quote
Old 08-27-2020, 06:56 PM   #24
Jack Shaft
BANNED
 
Join Date: Dec 2019
Posts: 1,196
Default Re: Rusted block, repairable?

I learned my lesson with model a people,no trades,no labor...set a price and I'll buy it if its a good deal..good luck
Jack Shaft is offline   Reply With Quote
Old 08-28-2020, 08:31 AM   #25
daren007
Senior Member
 
Join Date: Apr 2015
Location: Saint Cloud Mn
Posts: 745
Default Re: Rusted block, repairable?

The spray many use?
daren007 is offline   Reply With Quote
Old 09-12-2020, 06:51 PM   #26
Sckxyss
Junior Member
 
Join Date: Apr 2020
Location: Lachute QC Canada
Posts: 26
Default Re: Rusted block, repairable?

Sponsored Links (Register now to hide all advertisements)
Finally i buy a diamond B block from a barn find BB truck.
A bird nest in the exhaust manifold, squirrel nuts in the water pump but no cracks on the block. Pistons are nominal size, need oversize pistons and fresh cut of the valve seat and after ready to go. Not cheap but at least this one have a counterbalance crankshaft.
Regards.
Sckxyss is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 05:58 AM.