Exhaust log pressure testing.

[1973 Hondo]

Got the new 455 started last sat, and when the engine got to temp i had white smoke, right off the bat. So i took it home and dropped the logs and ran the water from the house with no leaks, so i took off the manifold and all four corners were soaked and had been dripping in the cylinders? so i replaced the gasket with a valley pan, and have not tried it yet, but if this doesnt fix my problem, im thinking it might :confused: be my exhaust logs, Does anyone know how to pressure test these? Just being paranoid i guess.

[Blown 472]

What was the outside temp when you fired it?

[Oldsquirt]

Hondo, any competent machine shop should be able to pressure test your logs....
Now, about that intake gasket. If you are running an aftermarket aluminum intake manifold, you should not be using the stock style "valley pan" or "turkey tray" intake gasket. You need to run composition style gaskets. As far as I know, only Mr Gasket makes these for the Oldsmobile. You should have no trouble finding them.

[Blown 472]

Check out SCE gaskets, they make some really nice stuff, I was having trouble with the intakes on my ford sucking the center ports into the runners, I talked to SCE about the felpros and was told since felpro got sold they changed their material thus causing this problem. I have seen this on chevys too.

[Wet Dream]

Hey Squirt, I'm getting ready to replace the cast intake and install the aluminum one on a friends boat this weekend. When I did mine (al intake) I unknowingly used the turkey tray with the blue goo and haven't had any probs to date. I was told that you can even use the blue goo instead of any material. Is this true?

[1973 Hondo]

Outside temp was around 65 to 70 and engine temp was 140?

[Oldsquirt]

Wet Dream, if you check with any of the manufacturers of aluminum intakes, you will
find they recommend composition gaskets or in Edelbrocks case "in a marine/competition
application, contact Mondello Performance...for correct gasket kit". Mondello recommends Mr Gasket.
Unless much time/money was spent getting a perfect match between manifold and head, you would be foolish to eliminate the gaskets and just use silicone sealant. Way too much variation in the surfaces. Would you really want to risk having a cylinder run lean and possibly burn a piston? That was how I learned the "turkey tray" lesson many, many years ago.
For those situations where you do use silicone(around the water ports, in the corners between head and block and even across the block end rails), use the black or ultra-black. On exhaust manifold gaskets, use the high-temp red. The blue stuff is low performance in comparison. Toss it in the trash.
Hondo, you are aware that the hot water being discharged from the engine exits via the exhaust, right? If you saw steam(as opposed to a flow of hot water)coming from the exhaust, you may have had insufficient water flow. When you run it "on the hose" you will see both hot water and some steam. Perhaps more details about the exact situation.....

[1973 Hondo]

But i also had a little water in the oil, it was definatly steam, i just dumpped the back end of the boat in the water to test it on the trailer. When the temp got to 140 it started steaming bad, and you could smell steam?

[Oldsquirt]

Mike, the water in the oil could quite likely have come from the intake gasket not sealing around the water crossover ports. Another possibility(often overlooked) is the steel timing cover plate. They get corroded around the water ports and leak into the oil. I don't see too much chance of the intake leaking water that then goes into a cylinder. Kind of a difficult path, but not impossible. If you had steam from both exhaust tips, I'd think it even more unlikely.
If you did indeed have steam from both tips, I would lean towards insufficient coolant flow. The alternative would be having a double failure in the engine, one on the left bank and one on the right. This just seems unlikely.

[1973 Hondo]

Ok I can believe that , but , what about the water in the oil, it seems like the water was dumping in the cylinders at all four corners of the intake gasket? The gasket was soaked.

[1973 Hondo]

SO waht your saying is, the water cumming out was to slow , ie evaporating before it could get out? It looked like i had a good flow?

[1973 Hondo]

LMOA guess i know where my mind is? I meant coming....LMFAO

[1973 Hondo]

Also i had just water in the valley of the engine, just standing water?

[HOOTER SLED-]

Had the same problem before. Changed the intake gasket two times. On the third time. I used the metal gasket with black high temp RTV. It finally worked. I made sure to use plenty of sealant(not over do it). Third times a charm I guess. Good luck.

[Blown 472]

1973 Hondo:
SO waht your saying is, the water cumming out was to slow , ie evaporating before it could get out? It looked like i had a good flow? Freudian slip???

[Blown 472]

1973 Hondo:
Also i had just water in the valley of the engine, just standing water? That could have come from pulling the intake.

[1973 Hondo]

Ok so what is good flow and good pressure out of the jet pump? Jacuzzi wj model? Or should i say how do you set it for the best results? Sorry for all the ? but im the fng learning the hard way!!!