I am still having problems with my 460 in my Sleekcraft. I have tried the ideas you guys gave me but no luck. I have posted on the Just Jets, but I thought maybe someone over here had some insight, I am desperate! A ton has been spent on trailer and cosmetics. Out of money and patience.
The Engine is building too much crankcase pressure (I think) it is blowing oil out around the distributor and out of the dipstick. Even at a quart low, it is doing it. It is soaking the engine down. The motor runs good and doesn't knock or noticeably smoke. It has good oil pressure. I have now two breathers. One on each valve cover. I have the pcv valve also on one valve cover and I have replaced the o ring with the correct one on the distributor. I have even put rtv silicone around the distributor, but it is coming out around it!
This weekend we finally got enough water in our lake to run the boat and I have this major malfunction. I do not know where to go, nor what to do. I hate both physically and financially to pull the engine, especially if I don't know what the problem is. Any advice would be greatly appreciated. Please help, I am out of ideas.
Thanks!
Obviously you're building excessive crankcase pressure. Have you tried a compression/leakdown test to check the engines shape? Worn valve guides or rings will let combustion gasses into the crankcase and give the effect you're experiencing. Knowing what you're working with will point you in the right direction, and it might unfortunately be the dreaded rebuild. Maybee yoou'd luck out with just a valve job.
Craig
Craig
I 2nd that
I guess the next step is a compression check.
When I got the boat the guy said it had a stuck valve in it at one time. I replaced the intake manifold with an aluminum one, and the engine was very clean with no build up in it. We will see what the compression check reveals, I will post the results. Maybe someone else is having the same malfunction. It sure is discouraging.
Do the comp test with a warm engine! Not cold. That will only tell you what the comp IS not where or how much compression is being lost due to bad piston/rings, valves or even a leaking head gasket. You need to do a leak-down test after the comp test to be absolutely sure what & where your problem is. Not being a Ford guy I cant say this for sure but you could be over oiling the top end possibly, do you know what oil pump is in it or how the engine oiling was set up?
I assume since the engine has never been apart, this is the orig. oil pump.
It is a hardin marine 320 hp, 460 from 1976.
I also am not a ford guy, so I am really at a loss.
If I have a leak down, does this cause the engine to pressurize the pan and blow oil out the distributor?
I say run a PCV
Sounds like a cylinder leak somewhere...maybe stuck rings in one cylinder or something! Good luck!! [Go with the leak-down test] T.R.C
[QUOTE]Originally posted by 76 Sleekcraft:
If I have a leak down, does this cause the engine to pressurize the pan and blow oil out the distributor?
No, if you pressurize each cylinder 1 at a time you have a special gauge that shows how much air is leaking as compared to how much you are filling the cylinder with. For instance if you found that you had 1 cyl that was leaking 90% you should be able to determine where it is going by listening into the crankcase or through the carb or out the exhaust! The air that is leaking when you test just blows past what ever is not sealing that cyl properly & causes no harm when doing it. If you had a completely sealed crankcase you'd blow every seal & gasket the second you lit the ignition but you don't, you said you have 2 breathers & a PCV just like any normal engine. Do the leak down test if you are not sure you have good compression in all holes, if you do have good compression and they are all near the same there is something else going on but I suspect based on your info that you have 1 or more cyl's that are not sealing at all or very little.
Just my opinion & how about a rating for explaining the leak down
I agree with what the others have told you. Do a compression test first and then a leak down test. FYI, you'll need a leak down tester to do it. Snap on and many others make them or perhaps you can find someone close to you that can loan you one or even help you do it. Not a difficult process, just the gauges (good ones) can be a little pricy. The leak down tester is a different piece of equipment than a simple compression gauge tester. Just wanted to clarify this since it seemed you're not familiar with it.
Your problem could also be a blown head gasket into the oil valley or something relatively easy to fix but if so the engine probably would run poorly in addition to the oil blowing out everywhere. From the sounds of it you have some serious crankcase pressure goin on. Hopefully it will turn out to be something less than a complete rebuild for you. Those 2 tests will tell you what's up though. Just listen where the air's going on the leakdown and it will guide you to the problem. (you will need a source of compressed air to do the leakdown test). A cheap trick I learned many years ago is to use a piece of vacuum hose up to your ear and probe around with the other end. You can pretty much pinpoint the air leakage doing this. Like a stethascope except cheaper.Here are a few links I found to tell you more about how a leakdown test works.
http://www.geocities.com/dsmgrrrl/FAQs/leakdown.htm
http://ourworld.compuserve.com/homep...ols/Tip420.htm
http://www.530i.org/530i-Test-leak-compression.htm
http://wabisabi.swarthmore.edu:9673/.../leakdown.html
Hope this helps and good luck.
[ October 22, 2002, 12:58 AM: Message edited by: Rexone ]
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