FL80 coolant and oil leakage

[RobClipper30]

Hi there to all,

Just purchased a Clipper 30 with a 40 year old Ford Lehman 80 HP Diesel which and a couple of things keeping me up at night thought I’d see if anyone had advice on. I’ve kept on same thread figure they might be related / good for extra context.

The first is the oil. After running it for a couple of hours I’ve seen a bit of oil in the bilge. If I had to guess it would be maybe 50ml at the end of the days cruising. Hard to say because there’s also some water down there (leaky rudder seal, whole other problem!).

After maybe 10 hours or cruising I checked the oil levels recently and i did see the dipstick go from full to in between full and safe..I’ve filled up maybe 300ml to top it up. Is this just kind of normal for a 40 year old engine?

Second thing is the coolant.. on my maiden voyage the alternator belt came off (go figure).. engine got to 220 degrees / max temp on gauge before I realised - maybe 30 minutes in.. the coolant was boiling at that point.. had a mechanic come and fix the belt and top up the coolant which was fine and both the main tank and the smaller plastic secondary tank were full to brim but recently noticed the secondary / plastic tank about 2/3rd full and coolant sitting down in the tray above the bilge. I guess same question here - normal kind of burn for the engine, or a red flag?

Also I’m a complete novice in all things mechanical so please forgive me if the syntax I’m using isn’t correct. Would appreciate any advice or guidance particularly if it’s in laymen’s terms!

 

[Juliet 15]

It's probably more important to identify where the oil is coming from than how much oil is leaking. 50ml doesn't sound like much (for those of us from the US how many ounces or teaspoons is that?).

you may want to locate the piece that appears to be the oil leak source then look it up in the manual. Put a pan underneath the leaking component then you can let us know both where the leak is coming from and how much it leaks in a set period of time. I feel certain there are Ford experts who can help you determine what's "normal" here.

Coolant disappearing after an overheat would worry me. I would first check the dipstick on the oil to see if there are any signs of milky sludge or something that might look like coolant contamination of the oil. If nothing, I'd check the oil level and the coolant level very systematically. For example, check them both cold, mark them, then run a set number of hours. Let them completely cool again (like for a day or more so they're as cold as when you first checked them). I would probably do this 2 or 3 times unless there was a big and obvious change that removed any doubt.

If over that 2 or 3 runs the coolant goes down, the important question is does the oil level go up? If so, you may have coolant going into your oil. That is bad, and I think you'd want a mechanic to diagnose and repair that.

If the coolant goes down but the oil level doesn't increase and you continue to see coolant leaking out under the engine then I suggest you ID the source of the leak. It may just be a gasket that needs to be replaced.

That's my thinking but I could be missing something. What do the engine gurus on here think?

 

[Comodave]

The oil leak may be from overfilling the engine oil. Lehmans don’t like being overfilled. You need to drain all the oil and fill the engine with exactly how many quarts is specified and then mark the dipstick at full. The dipsticks have been known to be wrong according to Bob Smith, he helped design the marinizing of the engines. This is a known issue. I would put some oil absorbent pads under the engine and see where the oil is dripping from. That will give you an idea where the leak is if it isn’t a case of overfilled oil. Then call Brian, Bob’s son, at American Diesel. He is the Lehman guru. 804-435-3107.

 

[SoWhat]

Put some aluminum foil baking pans under engine. Line them them with paper towels. Should be able to narrow leak down.
Clean exterior of engine with isopropyl alcohol or acetone. Jam some paper towels wherever you can. Again, it helps to spot leaks.
Watch exhaust smoke. After warmup should be very very slight amount of white or grey smoke. Worn engine will burn some oil.

I would consider 300ml to be excessive but not critical.

 

[Greg S]

"both the main tank and the smaller plastic secondary tank were full to brim but recently noticed the secondary / plastic tank about 2/3rd full and coolant sitting down in the tray above the bilge"

The small plastic secondary tank is not supposed to be full when engineiscold. Because it was full there was too much coolant so when you next ran the engine, the engine coolant expanded and was pushed into that expansion tank where it is supposed to go. Trouble is, it was already full. Expanding engine coolant caused overflow resulting in the spilled coolant you saw.

 

[Marco Flamingo]

I have the same boat, same age, same engine. At first, my coolant level was dropping after a long run and I found that it was leaking back where the coolant enters the hot water tank. Most of the heater hose had been replaced over the years, but not a couple feet back there. The hose "sweat" when hot and must have mostly evaporated. New hose fixed that issue.

From the picture in your other post, it looks like your coolant overflow bottle is not the aftermarket reclamation type. Those are a sealed system. Your bottle seems to be only an overflow catchment right underneath the original metal overflow tube. I still have the original system and after fixing the HW leak am having no issues once I found the proper coolant level.

If you fill the coolant reservoir on a FL up to the top, it will poop out the excess. The "excess" is about 1/2 of the level in the tank. It seems that more coolant would be better, but these engines doesn't think so. I made a dip stick out of a Pop Cycle stick. Although the tank will hold 2 inches, approximately 1 inch is full and 1/2" is empty. You basically need enough in the tank to "burp" the petcock on the manifold (if you've seen how to do that on TF).