The Terry Burtz 5 main bearing engine blocks are back on track.

[denniskliesen]

I’ve built this engine and helped a good friend with his. What page or pages are you referring to?

Was there a user guide shipped with the block? There was a guide shipped with the block on the first run. My new kit is at the warehouse and I’m picking it up Monday so I don’t know what is in the box this time.

[Terry Burtz, Calif]

In section 2) Common Sense and Assembly Sequence in the "Builders Guide" found at www.modelaengine.com, there is a paragraph addressing how to check for oil system leaks.

The paragraph found in the "Builders Guide" is pasted below.

It is important to verify that there are no open passages or leaks from the pressurized oil system. When the short block is assembled, remove the lower bolt (A-21111) from the Cylinder timing gear cover side (A-6017) and apply 40 PSI air pressure while checking for leaks at the rear main oil galley plug, the castle nuts for main bearings, the interface between the cylinder block and flywheel housing, the rear main seal, and the interface between the rear main bearing cap and cylinder block.

[denniskliesen]

Terry, thank you for posting that. I don’t think some people are reading the online guide. Is there a guide that is shipped with the block? I highly recommend reading the online guides.

[JOHNCL]

Terry, the pasted paragraph is not the response I expected. My point is that your photographs could better include, say, arrows pointing out the galley plug locations. You've asked for suggestions, BTW. I am surely not the only one who worked to find the plug locations.

John

[plumber3]

Terry
Is there any advantage to seal the inside of the block with a ceramic or paint type block seal?
Also do you have a price and availability on your new 5 bearing cam. Is it a 340 cam similar to Bill Stipes?
Joe

[Terry Burtz, Calif]

Sponsored Links (Register now to hide all advertisements)

Joe,

The new camshaft has a 0.340-inch valve lift, the intake and exhaust lobes are separated by 113 degrees, and the seated duration is 248 degrees.

It is made from nodular iron which is the material of choice and used in nearly all new production engines.

The lobes are induction hardened to Rc 58/62 to minimize wear, and the 5 bearings and center gear are hardened to Rc 40/52 to keep the gear teeth from becoming brittle.

The new camshaft has passages that will supply pressurized oil to the plunger at the front of the camshaft and if the new camshaft is used with our “New Engine Kit”, there will be 17 pressure-fed bearings instead of 16.

Ford drawing A-6250 was used for all interfacing dimensions.

The new camshaft can also be used in all Model A, Model B, Russian GAZ, and German G28T engines.

The retail price is $375, and the 1st production run is complete and being transported in a shared container.

[JOHNCL]

The more I have thought about the four mains' studs for cylinders #1 and #3, and worked with trial fittings of the studs, nuts, and bearings the more I have been thinking of adding O-rings beneath the castle nuts (in addition to the other sealants suggested by Terry. Those studs and their holes are subjected to the same oil pressure as the bearings. I want to avoid any leakage at the castle nuts' interface with the block. What do you guys (and Terry) think?

[denniskliesen]

It’s worth a try if you can find o-rings thin enough. Snyder’s and some others sell a flat washer with a rubber seal in the inner hole of the washer. It would also be worth trying packing and possibly an o-ring at the inside of the bore. It would need to be thin.

[Chris Haynes]

I picked up my Block, Rods, Crank, and Flywheel from Terry today.

[johnneilson]

I think these are what you are referring to, I have used them in other applications.
https://www.mcmaster.com/standard-wa...s-and-washers/

John

[Lawrie]

I Use a metric viton o ring,1.5 mm section and If I remember correctly 10 mm id.I made a special little installer for them and insert the down the reduced part of the stud from the bearing cap end,
Lawrie

[Model A Ron]

How many engines are now state side? Just amazing this project came to life. My hat is off to you.

[SAJ]

JOHNCL, when my Burtz engines arrive soon, I will look to see if Dowty washers will do the trick.
I use these on the rear main bolts on my original engines and I think I have them under the external mains castle nuts too from memory.
Are these what Dennis and John are referring to?
My Dowty washer kits have a stiffer Shore A 80 Buna N than standard O rings for better sealing in this application .
SAJ in NZ

[Ruth]

Originally Posted by JOHNCL

I have been thinking of adding O-rings beneath the castle nuts (in addition to the other sealants suggested by Terry. Those studs and their holes are subjected to the same oil pressure as the bearings. I want to avoid any leakage at the castle nuts' interface with the block. What do you guys (and Terry) think?

Snyder's has sealing washer available. https://www.snydersantiqueauto.com/p...id=978757&cat=

[denniskliesen]

Originally Posted by SAJ

JOHNCL, when my Burtz engines arrive soon, I will look to see if Dowty washers will do the trick.
I use these on the rear main bolts on my original engines and I think I have them under the external mains castle nuts too from memory.
Are these what Dennis and John are referring to?
My Dowty washer kits have a stiffer Shore A 80 Buna N than standard O rings for better sealing in this application .
SAJ in NZ

The leak I’ve experienced usually in a similar situation was around of from the threads. I’ve never seen brand name, what was called a Dowty washer. They might differ from what is available here. The conversation I’ve had with Terry was his concern that original Model A engines did not have washers under the nuts. We do what we have to stop the leaks.

[Terry Burtz, Calif]

Thanks for everyone's comments.

To keep the exterior completely original and not have sealing washers under the castellated nuts, I like Lawrie's solution of using an O-ring around the 7/16 inch stud that fits into a 1/2 inch hole at main bearings 1 and 3.

The wall clearance between the stud and wall for main bearings 1 and 3 is 1/32 inch.

During the design, I tried to find 1/32 inch cross-section O-rings that would work, but they are not available in the diameters needed.

Lawrie's post made me look at metric O-rings, and they are available in diameters that I think will work.

A 1 mm cross-section O-ring is .0397 inches.

The 1/2 inch hole is 12.7 mm.

My thoughts are that a 1 mm (.0397 inch) cross-section x 12.5 mm (.4921 inch) OD O-ring will work. The ID of this O-ring is 10.5 mm (.4134 inches) and will stretch when installed on the 11.1125 mm (.4375 inch) stud. I'm thinking is that the stretch on the ID will increase the OD to be greater than 12.700 mm (.500 inches).

McMaster Carr O-ring 9262K156 or 1295N129 are both 1 mm cross-section x 12.5 mm OD and oil resistant.

Other O-rings that are 1 mm cross-section x 13 mm OD will work but they may be slightly harder to install because the 1 mm cross-section will need additional deflection.

McMaster part numbers for 1 mm cross-section x 13 mm OD O-rings are 9262K163, 1174N102, 1247N102, 1171n102, 9263K549, 1295N131, 1185N12, and 5233T19.

This information will be added to the next revision of the "Builders Guide" found at www.modelaengine.com.

[Model A Ron]

But how many manufactured in china and are now in the USA? It's just hard to think that a Model A can get a new china made engine after 90 years!!!

[Benson]

Terry,

Have you looked at Rocket Seals in Denver, CO for O-Rings or seals?

They have supplied parts for the Space and Defense Industry since 1956.

THE LARGEST O-RING AND SEALING PRODUCT INVENTORY IN THE WORLD
Since 1956, Rocket Seals distributors have offered OEM and MROs the sealing product inventory and specialized expertise you can trust.

https://www.rocketseals.com/

[JOHNCL]

Terry, and you other builders, thank you for your valuable comments. I believe the O-ring on the 7/16" part of the stud followed by sealant impregnated wrapping string and possibly another O-ring could create a long compressive seal continuously compressed by the engine oil pressure. The top-side washers under the castle nuts can still be used when their appearance does not distract from judging standards. I would bet that existing builds that have not experienced oil leaks have used the wrapped string idea put forward by Terry in the manual.

[Terry Burtz, Calif]

The latest revision of the “Builders Guide” dated 3 January 2022 is on the website (www.modelaengine.com) under the tab “Guides”. Added material includes a head nut torquing sequence, source of Silv-O-Lite thin ring pistons, a caution about using pistons with offset wrist pins, sealing the #1 and #3 main bearing studs with an O-ring, added part numbers for SKF/Chicago rear main seals, added engine builders and parts suppliers, and unwarranted modifications. Please use this latest “Builders Guide” when building an engine.

We will be at the Turlock, CA Swap Meet on January 29 and 30, 2022 (www.turlockswapmeet.com) held at the Stanislaus County Fairgrounds. We will be in building VO and sharing space ID with John Lavoy which is across the aisle from the snack bar.

We will display the “New Engine Kit”, “New Flywheel”, and “New Camshaft”, and offer a discount for orders placed at the Turlock Swap Meet. I will be there to answer any questions.