A motor, mid range, acting lean, until 5500 RPM

[Skoontz]

Jeff:

Is that the same Goober Von Schloppen that is red in color, made by Permatex, used in a two part blend? We use that in the gear case and it stopped all the leaks...If not, I'll get some of the stuff later in the week....No money right now, work has never been this dead in 30 years....

[G Stillwill]

You can also use Loctite 518 jell seal same stuff. The 1.69 oz will do about 15 A motors. You can use it to seal the gear case halfs to but I have better luck with Three Bond 1194 for those which is the same stuff as the no longer avalible Yamabond#4 . The permatex you used wont last and will leak if it already hasnt.

[trident]

Loktite 518 (Gel-Seal II) is the right answer. The old Permatex goop washes out as a 2 stroke crankcase sealer.

Trick is use a very thin film of LokTite. Too much and the case cover will 'float' on it, as a sort of formed in place shim, making the factory line bore out of round. Then the crank train rattles around...

BTW, the LocTite porosity seal is #290.

Hope this helps.

Jerry Wienandt

[Skoontz]

Thanks again guys. I'm betting we have a combination of allot of stuff going on here. Time to yank it down and get back to the lake next weekend.

[johnsonm50]

Preventing the shimming effect while sealing the imperfections is what Ive seen in the manual as to why to use jel seal and not general purpose sealer. Carb 2nd-ary air will usually manifest as pulsing in small OMCs so I doubt carb porosity. Rich or lean should be looked at as well as double checking the carb internals and mix for the possibility of contamination. And just in case, Ive always found that if you "adjust" the carb in a barrel it will be lean on the boat. good luck

[ram95]

Bill, when you read this note, please don't think I'm trying to be a smart-as. I just think it might be helpful for you to know exactly what the OMC manuals say (which aint gonna help too much) so at least you know there isn't some magic cure in them.
From your description of events, it would sound like a 'fuel' problem. OMC manual 210641 (for the EKT-10S APBA Class A Racing Motor) isn't any help - it sends you to OMC Manual 507508 - which on page 2-17 you will find "Carburetor Cleaning, Inspection and Repair-All Models" . And, you will find the disclaimer/statement about NOT using a hot tankl or soaking in carb cleaner, and their reason "Soaking the carburetor will remove the casting sealing compounds and the sealing compounds used to seal around the metering tubes". They suggest you use "a syringe filled with isopropyl alcohol". If you have OMC Manual, 507547 pg 2-34, it will show/tell you how to invert a carb and fill the float cavity with alxohol to see if it leaks out around the spill tube in the carb throat. It also tell you to get some "OMC Ultra Lock" to seal it if it leaks.
Now you know what the factory has said. I doubt that this "leakage" thing is where your problem is. Except, maybe the little rubber tube in the float cavity is hardened and poorly connected - check that out.
Hope I've saved you from running out and buying a bunch of manuals you don't really need or that are of little help. Good luck.
Alex, the Mad Russian 12A DSH

[ram95]

Bill, since I already have all this tech crap laying here all over the bench (and time on my hands), OMC Ultra Lock pn is 500422 but it's same as LocTite 271. Also, something a lot of guys neglect to do is clean off ALL the crankcase sealant the factory used in the first place. It is really hard to see cause it's so thin but it is there. And when you put your sealant on top of it you can create internal crankcase pressure passage. Here again, OMC ( BRP!!! ) has some good stuff which works. PN 771050 "OMC Gel Seal and Gasket Remover" works so you can disolve the old 518 or whatever was on your crankcase flanges. PN 771087 "OMC Cleaning solvent" cleans the flanges prior to using 518. PN 772032 is "Locquic Primer" ( LocTite 7649 is same ) and is used to 'prime' the surface before applying the 518 sealant - it helps the sealant cure. There are other ways to get-er-done but this stuff works and I keep it on hand.
Alex

[ricochet112]

Bill, when you read this note, please don't think I'm trying to be a smart-as. I just think it might be helpful for you to know exactly what the OMC manuals say (which aint gonna help too much) so at least you know there isn't some magic cure in them.
From your description of events, it would sound like a 'fuel' problem. OMC manual 210641 (for the EKT-10S APBA Class A Racing Motor) isn't any help - it sends you to OMC Manual 507508 - which on page 2-17 you will find "Carburetor Cleaning, Inspection and Repair-All Models" . And, you will find the disclaimer/statement about NOT using a hot tankl or soaking in carb cleaner, and their reason "Soaking the carburetor will remove the casting sealing compounds and the sealing compounds used to seal around the metering tubes". They suggest you use "a syringe filled with isopropyl alcohol". If you have OMC Manual, 507547 pg 2-34, it will show/tell you how to invert a carb and fill the float cavity with alxohol to see if it leaks out around the spill tube in the carb throat. It also tell you to get some "OMC Ultra Lock" to seal it if it leaks.
Now you know what the factory has said. I doubt that this "leakage" thing is where your problem is. Except, maybe the little rubber tube in the float cavity is hardened and poorly connected - check that out.
Hope I've saved you from running out and buying a bunch of manuals you don't really need or that are of little help. Good luck.
Alex, the Mad Russian 12A DSH

The carbs on the legal "A" motor don't use the rubber hose for the idle circuit, it was the later models that did. Those that did have the hose were modular carbs and had plastic bowls and top covers (phenolic?).

ADD; 1989 and newer used the rubber tube inside.

[trident]

Clean is good.

Zip Strip, any hardware store... same active ingredient as many gasket/sealer removers.

Also, in classes where permitted, a light draw file dress up of mating surfaces knocks off any dings, nicks, and raised areas around dowel pins. Better fit, better seal.

The goal is perfect metal to metal seal, which is impossible. Just enough sealer to fill micro imperfections is the goal. Any ooze around edges after torquing indicates too much sealer.

Hope this helps.

Jerry Wienandt

[Skoontz]

Alex:

Greatly appreciate the tech help. I'll play with this in the next few days, but let me ask here. Does it make any sense to pressurize the crankcase first, we do this all the time after installing natural gas pipes by sealing the pipe with one end having a 0-15lb gauge, then using a bike pump or compressed air with a regulator. With gas pipe i usually pump to 15lbs and if it holds overnight, it will pass inspection so we can fill the trench. With this, I would use it to spray soap water around the crankcase halves and upper/lower seals, just for yucks and giggles to see if we have a crankcase pressure issue, carb issue, or a little of both.

Anyhow, thanks again, I'll picture post when I get on this thing and tell you all what happened.

[Dave M]

File ?

Clean is good.

Zip Strip, any hardware store... same active ingredient as many gasket/sealer removers.

Also, in classes where permitted, a light draw file dress up of mating surfaces knocks off any dings, nicks, and raised areas around dowel pins. Better fit, better seal.

The goal is perfect metal to metal seal, which is impossible. Just enough sealer to fill micro imperfections is the goal. Any ooze around edges after torquing indicates too much sealer.

Hope this helps.

Jerry Wienandt

I thought y'all only used bridgeports, and left the files to Lyle.

[trident]

Nah, we just leave the hacksaw and big hammer to Lyle. Everybody uses files... notice though, the suggestion was lightly dress...

OK, on this pressure thing, follow me here... we get alternating positive and negative pressure pulses on each cylinder. Everything in the crankcase is 'sealed' to the outside by rings (with end gaps), reeds, seals and so on, but there are 'leaks' between cylinders, like the labyrinth seal center main bearings. Pressure oilers are 'leaks', too. V-6's have ring gaps in the crank seal rings. The point here is that the block and case with endcaps needs to be sealed to the outside on the splitline, but all those other 'seals' only have to hold for, what, milliseconds?

Don't bother with a 24 hour leakdown test. Or even a 5 minute one...
Just clean, seal, and properly assemble the short block and be done with it.
It ain't Rocket Surgery, just attention to detail.

Jerry Wienandt

[jtower3941]

Hi
Have a 102 Yamato just cleaned carb. Manual say 1 1/2 turns of approx 38 klicks for needle adjustment for starting. How many klicks richer or leaner could be expected for racing.

Jim