Testing blocks in the home shop

[Karl Wolf]

Originally Posted by Ken/Alabama

Gotta ask, so is peening around a valve seat a bad idea? I’ve never done it but I have a Kwik-Way tool for that very purpose. Just curious

If it's to hold a loose seat in place, bad idea.
It will not transfer heat well and will likely rattle around.
May further damage the block.
If the seat fits tight, won't hurt, but no help.

Karl

[Karl Wolf]

I had a shop with a flame cutter use a head gasket to cut a steel plate for the combustion chamber shapes, then I clamped the plate to a cylinder head to drill the head bolt holes.
Gasket material is a theatrical dance floor rubber like material called "Marley".
This comes in huge expensive rolls. You may be able to hunt up used from a theater.

Karl

[Dave/Green Bay]

Flatjack9 here on the Barn fills the block with water then pressurizes if you see water anywhere you have a problems makes it easy to check. exhaust posts . Dave/Green Bay

[GB SISSON]

How many lbs pressure would be considered normal for a machine shop test?

[B-O-B]

Just remember to coat the plywood as it could swell if it got too wet too long.

[flatford8]

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Originally Posted by GB SISSON

How many lbs pressure would be considered normal for a machine shop test?

I have the Speedway kit. I think it works great and I tested a Merc block I tested at 55# for an hour and a half. I figured it was worth working on.......Mark

[40 Deluxe]

My idea is to bolt on the heads and water pumps. Use short lengths of radiator hose with freeze plugs clamped in the ends to block off. Get a cheap leak detector kit that uses florescent dye and a black light. Use the dye meant for oil and mix with Diesel fuel and fill the block. You will need little or no pressure as Diesel is good at wicking its way through tiny cracks. Carefully drain the diesel fuel, pull the heads and use the black light to look for cracks.

[GB SISSON]

Originally Posted by 40 Deluxe

My idea is to bolt on the heads and water pumps. Use short lengths of radiator hose with freeze plugs clamped in the ends to block off. Get a cheap leak detector kit that uses florescent dye and a black light. Use the dye meant for oil and mix with Diesel fuel and fill the block. You will need little or no pressure as Diesel is good at wicking its way through tiny cracks. Carefully drain the diesel fuel, pull the heads and use the black light to look for cracks.

I like this. Sounds like it would be hard to miss a crack with this system. I would still use rubber head gasket and dummy water pumps. This way I'm only testing the block. Amazon has a Mastercraft UV test kit with everything needed for the test. Price is 60 bucks. I have used trailer balls in the past to cap off hoses on my run stand. BUT... With Mark's 55 psi in there the block better be filled with liquid and not much air. Think 'potato cannon'.....

[Scotty's 52 F3]

I made water pump block off plates with a gauge, used heads and head gaskets. I used a bicycle pump to pressurize a water filled system and looked for leakage the next day.

I also pumped up with air only and submerged it in a big plastic tub over night and found no bubbles or burps. Gauge held steady.

I did find the typical "part number" cracks with dye penetrant and that was it. I was lucky.

If I did have bubbles or water leaks with this setup I would not be able to look into the cylinders but, I WOULD know there are cracks to investigate.

I made my test kit with what I had on hand.

[GB SISSON]

Originally Posted by Scotty's 52 F3

I made water pump block off plates with a gauge, used heads and head gaskets. I used a bicycle pump to pressurize a water filled system and looked for leakage the next day.

I also pumped up with air only and submerged it in a big plastic tub over night and found no bubbles or burps. Gauge held steady.

I did find the typical "part number" cracks with dye penetrant and that was it. I was lucky.

If I did have bubbles or water leaks with this setup I would not be able to look into the cylinders but, I WOULD know there are cracks to investigate.

I made my test kit with what I had on hand.

Excellent job there Scotty! I have every reason to believe that your double testing procedure was at least as thorough and accurate as I would get from a machine shop. Maybe on the first test I would use the diesel fuel and dye procedure, as when the heads or plates are removed the light will show just where that pesky crack is. If the block was on a typical engine stand, wouldn't the water/diesel/dye drip onto the floor below the affected cylinder? Another question... Would the block off heads and water pumps be the exact same parts for testing all 24 stud engines?
I almost wonder if it would even be necessary to magnaflux a block that passes Scotty's x2 procedure. Of course there's that part of me that wants to make some kinda coil by wrapping a cast iron sash weight with a thousand turns of copper wire and some diodes and vacuum tubes with a big rheostat and a couple of knife switches.... Obviously I know nothing about magnafluxing (or electricity for that matter.) What test would a typical machine shop perform first, and why?

[Scotty's 52 F3]

Thanks Gary. I had a set of head gaskets that were given to me is why I used them. I don't remember the brand. I sprayed them with white grease to hopefully be able to reuse them for testing purposes. I never tried though. I only had the one extra block. I stuck them in a plastic bag just in case.

My water pump plates are 1/4" plate I had laying around. Rubber sheet gasket material. It's been a few years so I don't remember if I made one water pump plate and checked one side at a time. I think you can flip it and use on both sides. I'd have to go dig out my kit from the shed.

I know my heads aren't cracked either.

[cas3]

I made a water pump block off plate just so I could fill the block with evaporust. It worked on both sides, although for this purpose I only did one side at a time. 1/4" thick, used silly cone for the seal.

[flatford8]

“What test would a typical machine shop perform first, and why?” you have to come up with a way to really clean the inside too......I’m not sure if that should be done before or after the pressure test....does anyone think that cleaning the scale out could expose a crack., post pressure test. Making the test wrong. I used 55# as a test pressure because someone on here said they used 80# and somebody else said 25# was plenty....I went in the middle...Mark

[Tim Ayers]

Originally Posted by deuce5wndw

https://www.speedwaymotors.com/Offen...Kit,25045.html

I bought one of these and it works like a charm!
edit: I just noticed they are on backorder! Sorry

Same here. Will be using it for three blocks in a few weeks.

[flatjack9]

Originally Posted by flatford8

“What test would a typical machine shop perform first, and why?” you have to come up with a way to really clean the inside too......I’m not sure if that should be done before or after the pressure test....does anyone think that cleaning the scale out could expose a crack., post pressure test. Making the test wrong. I used 55# as a test pressure because someone on here said they used 80# and somebody else said 25# was plenty....I went in the middle...Mark

I would clean as much scale and debris out first before testing.

[Karl Wolf]

Having done this in an automotive machine shop for years...
1) magnaflux top of block
2) pressure test block, 30 lb. air pressure would be ok.
3) use soap in water to look for bubbles. All over, inside and under block.
4) as a finish, raise air pressure to the point where the pressure
the test plate starts to leak air- 50/75 lbs. Look more.
Karl

[GB SISSON]

I have a pretty powerful pressure washer. I have an extra wand I could alter if needed. Seems maybe with the flywheel end up high, one could blast down into the head cooling holes, starting in the back, maybe a steel wire too. Drag/blast out loose stuff, then soak with vinegar/evaporust/some kinda acid?

[flatford8]

I found a broken parking brake cable that I used on my drill. I tipped the water pump openings down and ran the spinning cable in every place I could get it. Then used air pressure. A lot of stuff settles in there.......Mark

[GB SISSON]

Originally Posted by flatford8

I found a broken parking brake cable that I used on my drill. I tipped the water pump openings down and ran the spinning cable in every place I could get it. Then used air pressure. A lot of stuff settles in there.......Mark

Excellent! A rotary whip with ragged ends. I have a couple nice long cables from a tonner. I was thinking it could unwind up there if you spun it in the wrong direction and then I got to thinking you might have the outer casing involved as well. Pretty much a rotor-rooter, I like it! So after this, it's the pressure test. While the test kit is hooked up a good time for a vinegar soak?
Can't wait to learn about magna-fluxing.

[Scotty's 52 F3]

I did like you mentioned and blasted as much as possible with my pressure washer.

Then used cable in a drill and more picking and blasting.

Then a soak with phosphoric acid and it looks like new metal inside. It only dissolves rust. Will not damage the block.

I got it at Home Depot in the paint dept. Kleen Strip I think? It's for paint prep. About $14 a gallon the last time I bought it. I used it straight.