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Still leaking oil

J

jclays

Regular Contributor
The on going saga. As I have previously posted my port engine has an oil leak that appears to come from the front crankshaft/harmonic balancer seal. I've changed out the seal twice and now have replaced the harmonic balancer and seal. This mornings sea trials results were........ still the same leak. No more, no less. Trying to narrow down the leak. Appearances are from the front of the engine. The engine is mounted nose up a few degrees hence I do not think it is possible for a leak in the real of the engine to travel forward. No holes found in the timing chain cover.
 
Sounds like it isn't at the balancer-seal interface...that leaks the timing cover itself (maybe a pinhole from rust) or the pan-cover interface...

are the cover and pan bolts all tight?
 
Doesnt leak at low RPM 700 to 1000 harbor cruise speeds. My regular cruise RPMS of 2300 I will leak about 2/3 of a quart in a 28 mile run.
 
Try cleaning oil leak area and then put in a leak detection dye. With this you should be able to pinpoint the cause of the leak. The dye and light set up can be purchased at any good auto part dealer.
 
The pan/timing cover got me one time. I put it together dry, new pan gasket, without RTV along the big circle, big mistake.
 
Are you sealing the crankshaft/balancer key-way?

Often oil will whick it's way through the key-way, and out the front of the harmonic balancer. When it does, it's somewhat difficult to see where it's actually coming from.

Gravity doesn't necessarily play a role in this, in as much as mild crankcase pressure does.

If you pull the balancer again, try using an RTV sealant at/on the key-way area.

Also, and perhaps a long shot here...... do you have a short bolt installed at this location (blue arrow).
On some SBC's, this hole is open to the fuel pump push rod area (shown by the red line).
 

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First the crank pulley installs onto the balancer, then the large washer installs, then the bolt head mates to the washer.
That is a total of three surfaces, none of which are gasket or O-ring sealed.


.
 
This may help explain the path that the oil may follow.
 

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Filp Flop said:
There's no way in h*ll that 2/3 of a quart is gonna come from there !!.
Ricardo, Is that the only pic you could find ?. Pull up your big boy pants and quit trying to prove everybody wrong. :rolleyes:
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Filp Flop said:
Nice double talking when you're trying to save yourself from being a idiot. :mad:
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Your adult like forum contributions are greatly appreciated!

This is a forum. Members post their issues, and we read about their issues, and we try to help.
The OP's oil leak issue has not been resolved via several front seal replacement attempts.
We've made suggestions in hopes that one suggestion may cover something that was an over-sight first time around.

If you suspect where his oil leak is originating, let's hear your take on it! You are an expert, correct?
And while at it, try offering a few photos for him! They may help!

Otherwise, if you are not able to make a suggestion yourself, then what purpose do your posts serve, if not to disrupt the forum?

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Man; some rough talk around here. What happened, someone leave the door unlocked? I can stay at work to catch this grief.:mad:
 
diver_dave said:
What happened, someone leave the door unlocked?
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Dave, yes I believe so.
This is the same person who has joined again, under the radar, simply to disrupt these threads.
It's sad to see that an adult would be willing to spend their time this way, rather than actually helping the OP. :mad:


But back to the oil leak....... any updates???


.
 
RicardoMarine said:
Are you sealing the crankshaft/balancer key-way?

Often oil will whick it's way through the key-way, and out the front of the harmonic balancer. When it does, it's somewhat difficult to see where it's actually coming from.

Gravity doesn't necessarily play a role in this, in as much as mild crankcase pressure does.

If you pull the balancer again, try using an RTV sealant at/on the key-way area.

Also, and perhaps a long shot here...... do you have a short bolt installed at this location (blue arrow).
On some SBC's, this hole is open to the fuel pump push rod area (shown by the red line).
Click to expand...
Thanks for your reply Ricardo. I did put RTV on the keyway and also behind the big fat washer and even to the mating surface of the pulley but to no avail. Gonna check for the short bolt you are talking about. Dont think that is the case because I've had this boat since 06 and I started chasing this leak early summer. Its a bugger to find.
 
I thinking of wiping the underside of the pan and leak area clean with a solvent then putting a mirror (large) under the engine with a light on it. My son has a helmet camera that I can mount in the engine compartment filming the image on the mirror. I will take a short trip at operating RPM and see if I can film the leak and view on my computer. Sound nuts???
 
First of all..... good for you for using the RTV at the KeyWay, and also between the pulley, the large washer and bolt head.
People often over-look this, and end up with a small leak here.

jclays said:
I thinking of wiping the underside of the pan and leak area clean with a solvent then putting a mirror (large) under the engine with a light on it. My son has a helmet camera that I can mount in the engine compartment filming the image on the mirror. I will take a short trip at operating RPM and see if I can film the leak and view on my computer. Sound nuts???
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No.... not nuts at all if you can do this. Whatever it takes to pinpoint this leak......... I say..... "go for it!"


Is it safe to assume that you've checked/tightened the oil pan and timing chain cover bolts?



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Does the front of the pan have RTV between it and the gasket #7 (shown)? It must.. The marine pans are rough cast, maybe even sand casted, and will leak if you only rely on the dry gasket for sealing.

pan.jpg
 
diver_dave said:
Does the front of the pan have RTV between it and the gasket #7 (shown)? It must.. The marine pans are rough cast, maybe even sand casted, and will leak if you only rely on the dry gasket for sealing.

View attachment 6628
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Dont know. Pan has never been removed since I've owned the boat (2006) and has probably been on the motor forever. Never leaked until early last summer.
 
If you want to try the mirror, do it though I wouldn't expect stellar results once the drip gets on the mirror.

You may want to reconsider the dye that diverDave mentioned last year...modest investment and CSI-like results but real...
 
makomark said:
If you want to try the mirror, do it though I wouldn't expect stellar results once the drip gets on the mirror.

You may want to reconsider the dye that diverDave mentioned last year...modest investment and CSI-like results but real...
Click to expand...

Where do I purchase the dye? Do I just top off the crank case with it?
 
This would be a rather unorthodox method.... but it may be worth trying.

Wipe the suspect area down very clean.
Start the engine up, and try to re-create the oil leak.
Shut her down.

Take a clean stretched out piece of white cloth, and press it against the suspect area, and without moving it right or left.
Remove the cloth, and see if the leak has left any tell tale signs on the cloth.

At minimum, it should indicate whether it's to the Stbd side, center, or to the Port side.



.
 
You should be able to get the dye at any decent auto parts store...the bulb at walmart or home depot or the like.

The dye will come with instructions; the ones I've used you just add the little bottle to the crankcase...short periods of running the engine followed by diligent inspection is the best hint I can offer...
 
Will be trying the dye leak detector next trip to the boat. I will more than likely have to pull the harmonic balancer to get a better look around the pan lip and timing chain cover. The seal around the balancer is new with about 10 hours running on it. Will I have to change that out again?
 
Can't you just reach up with a clean paper towel and find oil after a short run? If it is sheeting down the front of the pan, then it's likely not the rotating parts. Fast idle in neutral should be as good as in gear/at speed to make a leak at the front. Did you try pulling the oil dipstick up slightly to make sure the crankcase is not getting pressurized somehow? But, my bet is still forward pan gasket; there is a lot of oil that gets slinged around up there from the chain.
 
In this case, I side with a bad seal on the oil pan..... when the engine is running at higher rpms, the splash in the oil pan flows over the dried out seal. ...Been there, done that.

it is hard to diagnose leaks from a forum, but I think you have all the possibilities listed
 
Cant get at the front of the oil pan/timing chain cover front lip. Old style "U" shaped yoke engine mount. Balancer just clears sitting in the center of the "U" pulling the balancer will let me look down the front for a bit. Will my balancer front seal have to be replaced if I re pull this balancer. The seal is new with about 10 hours of one weekend fishing on it. So is the balancer.
 
Might have found the cause.... Went on a fishing trip last Saturday. Oil leaked as usual only at higher rpms. Upon going below to check the engine oil I noticed that the dip stick was pushed out about an inch. Then I remembered that I've been noticing this every time I check the oil on this engine the dip stick is pushed out about an inch. Too much crankcase pressure? Possibly pushing the oil by the seal? Currently the engines have a PCV valve in one valve cover with a hose going to a vacuum fitting on the intake manifold. The PCV valve rattles when shaken so I know its loose. I check the hose and fitting for vacuum and remove the valve cover to see if the other side is clear.
 
OOOOOOOOOOh. there is a PCV... Doesn't sound like a stock Crusader 454. Each valve cover should have its own hose running up to a flame arrestor set of fittings. Free flow to the raw air intake. Engine is not making enough vacuum at high power settings to scavenge the crankcase, and its building pressure. Easy fix.
 
diver_dave said:
OOOOOOOOOOh. there is a PCV... Doesn't sound like a stock Crusader 454. Each valve cover should have its own hose running up to a flame arrestor set of fittings. Free flow to the raw air intake. Engine is not making enough vacuum at high power settings to scavenge the crankcase, and its building pressure. Easy fix.
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Not 454 twin 350s.
 
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