Heat increasing, oil pressure decreasing

[Ando]

Recently went from raw water cooling to fresh water cooling, but the heating issue was there before the change. Not sure about the oil pressure bc in the 2.5 years of ownership, I never paid attention to it until now (ignorance is bliss).

Overheating:
Goes from less than 100 to over 180 in 15min (at idle). I’ve acid washed and dismantled and visually inspected the whole cooling system twice and see no blockages. I did remove the thermostat before each flush. Original gauges, newer senders. I have a new in box Faria gauge that I will test with the sender. I will also adjust the valve to the thermostat a quarter turn and see what happens and then a full half turn to see what happens. And I’ll report back. I also ordered a Groco 3/4” thru hull and coated it with Barnicle Barrier by Petit that I will be installing in place of the original 1/2” thru hull which I assume is calcified. Note: The fresh water cooling system does have a steel wool filter prior to the return to the hx.

Oil pressure:
Never have I ever adjusted the oil pressure valve so I’ll be doing that and reporting back.

Any other ideas, comments, suggestions are invited and appreciated

Here are pics of initial start up and 15 thereafter

[Surcouf]

not sure I would call 180 as overheating.

See the poll, and the comments. Several owners are running at 180 especially with fresh water cooling. A4 will be happy @ 180

https://www.moyermarineforum.com/forums/showthread.php?t=3323

Would also depends if you sail in Maine, or in Florida

[Al Schober]

I'd remove the thermostat and see what happens.
Steel wool filter? First I've heard of such a thing. Is this a commercial item? I'd appreciate more info on it before giving judgment.

[edwardc]

Note: The fresh water cooling system does have a steel wool filter prior to the return to the hx.

I assume this means it is in the coolant side, not the raw water side. If so, I would remove it. There is no need for a filter in the coolant loop, and it will provide some additional obstruction. My experience with Moyer's FWC conversion kit is that it runs at 180 because it is reaching steady-state with the maximum cooling that the HX can handle. The thermostat is open all the time and is not really doing much about regulating. Any additional obstruction in the
cooling quickly results in higher temps at cruise RPM.

[ndutton]

Guys, remember that the gauge temperature is with the engine at idle, out of gear (no load whatsoever) and in 61° water.

[Boat]

180 is normal. mine takes a considerable amount of time to get up to temp. mine would never lift the needle off the peg unless i run at load for awhile. i am PNW puget sound though 54 degree water. the oil pressure on yours looks low to me though

[Ando]

Hi guys. Thanks for all the discourse. It’s comforting to hear that 180 is ok, but more comforting that running at ~150 is also reported & that’s what I’m shooting for. To that end, I will first adjust the valve at the thermostat and report back. Then, I will reopen it and remove the steel wool (yes, it’s on the fresh water side…before the hx return port) and report. Based on those readings I’ll evaluate the next steps (thermostat removal, gauge/sender issue, thermal readings of various areas of the engine etc.)

I still have to adjust the oil pressure valve.

Just gotta get back to the marina first

[Ando]

Update

Overheating issue:
I adjusted the valve going to the thermostat by a quarter turn and the heat hasn’t gone above 150 for about an hour of running time. What does this tell you all? Btw, the first 15 minutes of running time were constant running and the other 45 minutes were of on and off testing of the oil pressure). Which brings me to the second part, which also has me perplexed…

Oil pressure:
No matter how I adjust the oil pressure valve (almost all the way out, half way in or all the way in), the gauge starts and stays at ~0 unless I rev the engine and then it only goes up to a bit less than 20. Any ideas?
Notes:
1. Before starting the first time, I saw that the oil valve was way way out so I turned it clockwise about two turns;
2. Then, for the next hour or so, I turned the engine off then adjusted the valve and started again to check if there was any difference for a few minutes and then off again, adjusted, check a few minutes and off again; and finally
3. when I turn the engine off, the oil pressure gauge shoots to a reading of ~30

[roadnsky]

Not sure if you've already read this?

From Don in the TECH TIPS...

"In the event that you might be facing oil pressure issues that do not respond to normal adjustment (35 to 40 psi fully warmed up at normal cruise, and 20 psi or so at idle), you might want to consider the regulating valve found in the overhaul section of our online catalog before taking on any heavier maintenance on your engine. Many overhauls have been headed off by the installation of this “early model” style of valve.

Another significant aspect to the problem of regulation relates to the fact that the orifice in the block is not always perfectly centered with the centerline of the threaded shaft.

The effect of this misalignment sometimes causes oil pressure to take a nose dive during an adjustment, as the threaded shaft nears the end of its travel and forces the ball (or even the pointed shaft of early model valves) off to the side of the orifice in the block. In these cases, it’s usually necessary to use the regulating valve seatdressing tool shown in the specialty tools section of our online catalog to bevel the orifice slightly, bringing it into alignment with the shaft or ball."

You can read the entire posting HERE

[ronstory]

Ando--

Following Jerry's update above, when I swapped from the "modern" (eg. more cost effective, cheap) version with the ball bearing, spring and bolt/washer/nut to the original integrated cone/pin assembly, it got a few more lbs PSI. Most of it I think was due to a build-up of gunk on the pressure relief mating surface. I used one of Don's tools, but a hardwood dowel and some creative hammering/tapping will clean it up as well.

Also, I got a touch more oil pressure & stability using Indigo's external oil filter. Indigo's solution blocks the original oil regulator port and has an external oil pressure regulator built into the filter holder which make for much more convenient adjustment.

IMO, either is an improvement over the "modern" version.

[Ando]

Parts Are Ordered

Waiting the arrival of the bevel tool and the regulator. I'll keep you posted.

[Dave Neptune]

Ando, I'd try a mechanical gage to confirm the electric. Oil pressure would be somewhat constant and not just drop off as you state, perhaps a sender or wiring glitch.

I have never seen a filter on a cooling system only a strainer on the intake water line. I also feel "steel wool" would be a very poor choice of material and would only cause flow restrictions.

I'd really like to see a pic of this so called "filter" assembly.

Dave Neptune

[Ando]

Ando, I'd try a mechanical gage to confirm the electric. Oil pressure would be somewhat constant and not just drop off as you state, perhaps a sender or wiring glitch.

I have never seen a filter on a cooling system only a strainer on the intake water line. I also feel "steel wool" would be a very poor choice of material and would only cause flow restrictions.

I'd really like to see a pic of this so called "filter" assembly.

Dave Neptune

Awesome idea, Dave. Thx. Can you give me details on the mechanical gauge (type, cost, where to purchase one, and how to use it)? I have a gauge to test compression…will that work or is this something different?

The manual for the indigo hx calls for the placement of a temporary filter between the manifold and the hx return port. I’ll send pics of that part of the manual and the one I installed. I too was worried that it would restrict flow so I tested the unit prior to installing (using a garden hose) and I was surprised to find out that the flow was not restricted at all. I was expecting some back flow (overflow) at the connection between the unit and the hose and there was none. The connection between the two was by hand (not screwed together or anything of the like). A primitive test, but it provided enough piece of mind to put it into action.

[Dave Neptune]

A std oil pressure gage and a cheap one is just fine. Just like the fuel pressure gages only for higher pressure. You can mount a tee at the "sender port" or the aft port near the oil pressure adjustment.

I had both an electric on the gage panel and a mechanical one mounted on the engine so I could see it with the cover off. I cold started my engine with the cover off using a permanent remote start switch so I could see both fuel and oil readings.

Dave Neptune

[roadnsky]

Can you give me details on the mechanical gauge (type, cost, where to purchase one, and how to use it)?

Our host sells one HERE.
It comes with instructions and is very easy to install.
I have it and it is great for comparing to my cockpit "electric" gauge.