Logo
FULL SITE MENU

Oil Leak, any good ideas?

C

CaboJohn

Regular Contributor
While I have the floor over the engines off (to work on the port engine) I took a look at an annoying oil leak on the starboard side. It leaks a quart every week or so into the bilge. Doesn't matter if the engine is running or sitting. I cleaned the bilge and put down absorbent material so I could be sure where it was. By standing on my head in front of the engine I easily located the issue. It is the dip stick tube.
On this engine (2002 350) there are two dip stick tubes (one on each side). They don't actually go into the pan, but go into a T fitting that hangs below the pan on the bottom of the engine. The inboard tube (the one most convenient to check the oil) is dripping. I can barely reach under, but where the tube bends to go under the engine it feels rough, as if corroded. And that is where the leak is. It runs around the curve a little ways and then drips off well before reaching the T.
The obvious "correct fix" would be to pull the engine and replace (or maybe weld) the tube (or in my case remove it and block it off, as parts are not available, I could then check the oil from the other tube).
But "pull the engine"" is the expensive part. I have toyed with the idea of sticking something down that tube to block off the leak from the inside and then using the other side, but I am not sure how well that might work. I hate to pull the engine if some rags and a coat hanger might eliminate the leak or get it to a manageable level.

Comments? Ideas?
CaboJohn
 
Don't know if it is a "good" idea but how about taking the oil out of the engine to get it below the leak. Clean and scuff up where you think the leak is. Let it dry. Layer on some JB Weld, perhaps two or three thin coats each coat extending further up and down the tube, (over-lap). It has been my experience that JB Weld, if applied correctly, will outlive your engine !!!

Lot cheaper and less work than rteplacing the tube.....but it's not my boat !
 
I had a oil leak many years ago and tried everything, including marinetex, nothing worked. I thought it was the heat generated, especially when making 45 minute to 2 hour runs. At the end of the season I pulled the engine and replaced the tube and oil pan.
 
The problem with fixes from the outside is that I cannot reach the thing. But moving one, I determined that I could get at it if I only pulled the transmission since it connects to the pan near the rear of the engine.

Further study today convinced me I might be able to get there if I disconnected the hoses to the oil and transmission coolers. It will be tight but I can find a local with skinny arms. But now it turns out it is too tight for a normal wench. I am working up an alternative this weekend. Hoses are reinforced rubber with 1 inch nuts on the end.

If I get the tube out I will have it welded and reinstall. Or I can go the epoxy and heat shink tubing route if I can't find someone to weld metal that thin.
CaboJohn
 
Find someone who know how to oxy-acetylene gas weld--I've done miles of welds in this sheet metal (with my old expansion chamber business). I'll do it for you if you want to bring it to my shop in eastern PA.

Jeff
 
It's been my experience that it is much better to replace the tube then to try to repair it.

If you don't need the tube and the corroded area is above the normal (static) oil level, I'd be inclined to cut the tube just below the leak source and then plug it until you have the time/money/ambition to finish it off...
 
Well, it is nice to know that someone else had to change a tube. I am still having trouble believing that it has failed, and I don't yet have it off.. The leak is well below the static oil level (that is why it leaks) but I do have the tube on the other side of the engine as backup. Unfortunately, I will not be able to get that one off so I cannot move it to the correct side, but I can live with checking oil only if the power deck lid (or whatever you call it) is lifted. So if I cannot repair the leaker, I will block it off and reassemble.
Interesting discovery. The engines (350 Captain's Choice) come from Crusader with two identical tubes. In my installation the top of the inboard tubes (which contain the dipsticks) are about 1/2 inch lower than the outboard tubes, and so read "full" when the outboards are just below the "add" level. Crusader sells three different dipsticks that are selected depending upon engine installation angle. In my installation it appears that Pursuit, once the engines were in and had the correct amount of oil, pushed the inboard tubes down (bending them) until the oil level read correctly. The correct dipsticks for their installation either were not available or they just did not have them around.
I tried pushing the outboard tube (that I may end up using) down to match the inboard but quit after I had moved it about half way home. The drawing looks like the bottom end of the tube attaches to a fitting with a flare nut and an o ring. If I get carried away and break it there I will be pulling the engine for sure.
So if I end up using that dipstick I will punch some new marks and carry on.
CaboJohn
 
Did get the tube off today. Right after the tube turns horizontal to go to the fitting on the bottom of the pan, there was corrosion on the top surface with three pin hole links. Took it to a local shop and the brazed it for 100 pesos ($8). Painted and reinstalled. All is well.
 
Back
Top