New Raw Water Flow Sensor From MMI

[Administrator]

MMI is pleased to announce a new product offering, a raw water flow sensor fully compatible with our Cole-Hersee oil pressure and water temperature alarm system.

Click here for more info!



The trip point is set to detect when raw water flow is reduced to a rate just below normal starter RPM (essentially a little more than a trickle). Although overheating is already monitored by the Cole-Hersee alarm, overheating can be caused by a variety of factors. This sensor provides specific monitoring of intake blockage, system obstruction, and offers impeller protection (spinning in a no-flow environment).

Bill

[roadnsky]

Great addition!
I can think of at least TWO threads current right now that this would have avoided their overheat episodes.

[BunnyPlanet169]

Nice

One of which was mine.

Add to Fall alarm/FWC project....

[ndutton]

Jeff, I count three very recent threads where this flow sensor would have been of great benefit: yours, Taylor's and Jack Connick's. All three involved a zero raw water flow overheat that would have been detected instantly. Yeah, I'm likin' it.

[Mo]

SSSS SMOKIN...I'm impressed. That will counter many incidents of overheating and certainly lend to longer engine life....absolutely. My ear is tuned into sound of my exhaust water "blurping" in the water...it's automatic for me but this is a step up by all means. Bravo.

[hanleyclifford]

Hmmm

Good to 200 degrees. Any reason why it couldn't be used in the antifreeze loop?

[thatch]

"Flow sensor tests"

I was fortunate enough to be asked to do some testing on this sensor prior to it's addition to the Moyer line of products. Since it's installation about a month ago, I have logged about a dozen hours on three seperate trips and have nothing but praise for it's performance. My A4 is fresh water cooled with a "thin shoe" Oberdorfer pump with a 2 year old impeller on the raw water side. The sensor is installed just in front of my heat exchanger, mainly because it was a convienient location. My normal "innitial" start-up procedure on each trip is to start my A4 at the engine via parallel ignition and start switches and then to turn on the water intake after the engine has stabilized which is normally about 5 to 10 seconds. This method accomplishes two things, first it verifies that the flow sensor is working and secondly it prevents excessive water buildup in the water-lift. Despite a claim of a 7% reduction in flow rate, I have found virtually "no" change in my running temps. Over the years I have forgotten to turn on the water intake several times and this "forgetter's alarm" would have prevented those events.
"Note to Hanley" I have been using a "medium output" Bosch electric circulation on the coolant side of my system and I will most likely be adding another sensor to that side also....Great idea, thank's
Tom

[67c&ccorv]

Darn...I already added a raw water flow sensor to my vessel prior to this product coming out!

Mine is plumbed in to the inlet water flow from the raw water strainer to the water pump.

[ndutton]

Darn...I already added a raw water flow sensor to my vessel prior to this product coming out!

That just means you were on the cutting edge already realizing the benefit of such a sensor. Does yours work with the standard engine alarm system or is it stand-alone?

Good to 200 degrees. Any reason why it couldn't be used in the antifreeze loop?

On principle I'd say it could be used there if you're comfortable operating close to it's upper temp limit. Operating at the target FWC temp of 180° you're within 10% of the maximum. Not much margin of safety IMO.

[Mo]

Neil, what does your's run at. I think you removed the T-stat in your FWC'd...is that correct?

[ndutton]

I just had mine out for a good run yesterday. My cooling system is FWC, electric coolant pump, lengthy water heater loop, no T-stat, bypass fully closed.
Previous running temps were 180° - 195°. With the new flow sensor installed in the RW discharge hose (7% restriction) and a new M7 cam shoe in the raw water pump my running temps are now 140°@ 1500 RPM and 155°@ 2000 RPM.

Looks like it might be time to start tweaking the bypass valve.

[67c&ccorv]

That just means you were on the cutting edge already realizing the benefit of such a sensor. Does yours work with the standard engine alarm system or is it stand-alone?

Stand alone system...has a warning beeper and flashing light to alert you.

http://www.aqualarm.net/comerus/store/comersus_viewItem.asp?idProduct=35

[Administrator]

Bumped.

Bill

[ndutton]

Thatch and I were talking about this last week. As Hanley mentioned earlier Tom thinks with electric FWC it would also be a good idea to monitor the flow on the FW side of the cooling system. I've already experienced an electric FW pump failure (the first cheap, off brand pump I tried - lesson learned) so this is becoming particularly interesting to me.

[capnward]

overheating alarm and electric water pump questions

This thread makes me wonder:
1. If the raw water flow sensor is wired to the same alarm as the temperature sensor, how does it tell you that you have a problem in the RW flow? Shouldn't it have its own, preferably different sounding, alarm? But anyway it would be good to know there is a RW flow problem before your engine actually overheats. I am FW cooled, with no t-stat, and a thermostatic mixing valve. I installed a temp alarm on the front of the head this year, next to the gauge sensor, and it told me my RW (Jabsco) impeller had broken. I heard the alarm go off, shut down, then later after it cooled I noticed no water coming out the exhaust. A flow sensor would have told me sooner, before the engine got hot. Putting one in the FW line would be good too, but it would probably need replacing every time the temperature alarm went off, unless it had its own alarm and you shut down before the engine go hot enough to trigger the temperature alarm
2. What are the advantages to having an electric FW pump? Is it to flush the engine without running it? I have the new MMI 502 flange pump, and like it fine. I think I would rather replace an impeller than an electric pump.
3. Re #11; I don't see how restricting the flow by 7% in the RW discharge can make the engine run cooler, i would have thought the opposite. Does a new cam shoe really make a 40 degree difference? How soon do they wear out?
Thanks guys for your collective wisdom.