After enjoying a few hours sailing in the Ocean this weekend, we got down to testing the non-working engine gauges.
#1: Engine Temp Gauge.
Shorted the tip of the Sensor on the engine and the Gauge read max temp. - Ordering a new temp sensor
#2: Engine high temp alarm.
Shorted the tip of the 2nd sensor on the engine and the alarm light lit up and the alarm sounded. - Ordering new high temp sendor.
#3: Fuel Gauge
Gained access to the fuel tank area by removing the cabinet just above the shower seat. Inside I found a wire with a terminal end that had been tie-wrapped to the fuel line and covered with electrical tape.
Shorted that line to the tank body and the fuel gauge read full. - Ordering a new fuel sensor (the one with the magnetic reed switches, not the swing arm type)
I think I lucked out on these items.
Paul
Paul : You'll just have to install the new parts and see it that solves your problems.
BTW, the easiest way to get to the fuel tank is by taking the port side panel off in the aft cabin.
A thought
Quote from: britinusa on August 02, 2015, 12:05:24 PM
After enjoying a few hours sailing in the Ocean this weekend, we got down to testing the non-working engine gauges.
#1: Engine Temp Gauge.
Shorted the tip of the Sensor on the engine and the Gauge read max temp. - Ordering a new temp sensor
#2: Engine high temp alarm.
Shorted the tip of the 2nd sensor on the engine and the alarm light lit up and the alarm sounded. - Ordering new high temp sendor.
#3: Fuel Gauge
Gained access to the fuel tank area by removing the cabinet just above the shower seat. Inside I found a wire with a terminal end that had been tie-wrapped to the fuel line and covered with electrical tape.
Shorted that line to the tank body and the fuel gauge read full. - Ordering a new fuel sensor (the one with the magnetic reed switches, not the swing arm type)
I think I lucked out on these items.
Paul
Paul, what you have to make sure is that your temp sender and temp switch are properly grounded. It could very well be that they are a-okay, but the threads are not grounded. A VERY common problem. You can use a wire with an alligator clip to temporarily ground them to a good engine ground to test the gauges again. It would be rare for both the switch and the gauge sender to go bad.
What happens is corrosion on the bolts holding down the thermostat cap produces a poor ground. That's the only way the ground is transferred to the temp units.
I have been working on a little add-on to ground those units properly. If you want to try one email me offline - I'm looking for a guinea pig to try it out on. Even a slight corrosion will affect the accuracy of the temp gauge (which is only about +/- 15-20% anyway.)
Alternately you can remove the T cap, clean up everything, and reassemble using copper content never seize on the bolt and sender and switch threads -- then clean up the cap well, use a star lock washer under each bolt head to get a good BITE into the T cap. Then paint over the bolt heads well to prevent corrosion from creeping under them.
Ken
Good point Ken (no pun intended)
I'll go down to the boat and run a ohms test between the senders bodies (each of them) and the engine ground.
If high, I'll remove them, clean them up and reinstall as you suggested.
Thanks.
Paul
Quote from: britinusa on August 02, 2015, 12:05:24 PM
Gained access to the fuel tank area by removing the cabinet just above the shower seat.
In 17 years of owning our C34, and in reading
Mainsheet magazine articles since 1987, this is the very first I have ever heard of this "route."
Got any pictures?
Quote from: Stu Jackson on August 03, 2015, 10:37:19 AM
Quote from: britinusa on August 02, 2015, 12:05:24 PM
Gained access to the fuel tank area by removing the cabinet just above the shower seat.
In 17 years of owning our C34, and in reading Mainsheet magazine articles since 1987, this is the very first I have ever heard of this "route."
Got any pictures?
While I know I can take the door off that cabinet opening, I'm pretty sure it is all one piece of fiberglass and no way to get behind it short of cutting a hole in the back of the cabinet.
As we refer to it, the 'bog roll' holder is a wooden cabinet that is removed with just taking out 4 screws.
From the hole left after removing the cabinet box, I can reach the front end of the fuel tank and to top where the gauge is located.
I'm going down to the boat tomorrow (tueaday) night and will take a pic.
paul
To get to the fuel tank, remove the port aft cabin bulkhead/trim panel. To access the fuel tank gauge sender go through the beckson port in the port cockpit seat locker. To get to the shower sump pump, remove the teak toilet paper cabinet. To get to the engine gauges, remove the gauge panel and hopefully you have adaqute slack in the wiring harness and it is well supported to pull it out into the cockpit. That's the way it works on my 1990 C34.
Didn't get to the boat last night, Nature demanded attention (mow the lawn), so I'm heading down there this evening.
Reading some posts that found me, I got this from Boating Magazine 2011
http://www.boatingmag.com/how-to/installing-fuel-water-separator
QuoteStep 1
First, you'll need the proper kit. For outboards, that'll generally mean a filter equipped with a clear plastic collection bowl. For inboards, use a filter fitted with an aluminum bowl for gas, or a clear glass or plastic inspection bowl for diesel. A disposable filter without a collection bowl can also be used.
Paul
Quote from: Noah on August 03, 2015, 08:06:29 PM
To access the fuel tank gauge sender go through the beckson port in the port cockpit seat locker.
My Beckson port is so deep in my locker, there is no way I could ever reach it. If I cleaned out the locker, my 9 year old grandson could crawl in there and reach it but not me.
Not fun for you, but probably for him! Fortunately mine is well placed enabling access the sender and puck up tube assembly.
Anyone know the temp/resistance steps of the Engine Temperature Sensor?
I'm seeing 74ohms at ambient temperature (80+ Degrees)
Thanks.
Paul
Quote from: britinusa on August 05, 2015, 11:37:58 AM
Anyone know the temp/resistance steps of the Engine Temperature Sensor?
I'm seeing 74ohms at ambient temperature (80+ Degrees)
Thanks.
Paul
Always check the wiki first!!! I had posted the complete gauge troubleshooting guide on there in the engines section.
http://c34.org/wiki/index.php?title=Tachometer_Malfunction_Q%26A
Are you sure it's 74 and not 740? 600 - 800 ohms at 75F is normal.
Ken K
Some success.
I was able to install the new Fuel level sensor (removed the aft berth panel to gain access to the tank area, removed the bekson access panel in the port cockpit locker to allow passing the new sensor Up into the locker and then down into the tank) Works great.
No luck with the engine temp and high temp sensors. Installed 2 new sensors, ran the engine for 30 minutes, still shows minimal temperature.
Shorted the new sensors to the body of the sensor housing and the temp gauge read full right, and the temp alarm sounded (pretty weak!) and the light flashed.
I shorted the temperature sensor housing to the arm of the alternator support. Still no temp reading.
Is it possible that the engine earth is the problem?
Paul
Paul : Check to make sure they sent you temp senders and not temp switches!!
Unless me brain is fried (could be the way the day has gone). The temp sender if 1/4" npt, the hi temp switch is 1/8" npt
Ken
Paul
Somewhere in prior post I said to verify the Senders by checking them with a known good ground. You can do that only by knowing you have a good ground. If in question, you wasted your time.
Either ground to the bty negative post or verify you have a good ground somewhere.
A Voltage check between bty pos and the ground you're verifying, or check resistance between the battery neg and the ground you're checking.
The first thing to do if ANYone is having ANY electrical problem, is check, and recheck, and clean connections. DC current depends on both negatives and positives equally, not just positive connections!
Cheers.
Good point Ron.
I'll call CD to verify.
Paul
Quote from: britinusa on August 18, 2015, 09:05:03 AM
Good point Ron.
I'll call CD to verify.
Paul
Paul
It's VERY simple
Temp sender has a post terminal and is 1/4" npt thread (front of the Tstst cap).
Temp switch has a button (slide on) (i.e., takes a "Packard 56 terminal") and is 1/8" npt thread (same as pet cock on the top of the Tstat housing)
You cannot confuse the two.
Ken
Ken : Kubota does have a 1/4" temp sender and a 1/4" temp switch - believe me.
Whether CD has - I don't know?
A thought
Quote from: KWKloeber on August 18, 2015, 09:10:48 AM
Quote from: britinusa on August 18, 2015, 09:05:03 AM
Good point Ron.
I'll call CD to verify.
Paul
Paul
It's VERY simple
Temp sender has a post terminal and is 1/4" npt thread (front of the Tstst cap).
Temp switch has a button (slide on) (i.e., takes a "Packard 56 terminal") and is 1/8" npt thread (same as pet cock on the top of the Tstat housing)
You cannot confuse the two.
Ken
Ken, agreed, the Temp sender I installed has a threaded stud for the connection to the ring terminal on the wire from the gauge.
The Temp switch has a slide on clip. And the thread on the switch is much smaller than the Temp sender.
Paul
Quote from: Ron Hill on August 18, 2015, 11:42:43 AM
Ken : Kubota does have a 1/4" temp sender and a 1/4" temp switch - believe me.
Whether CD has - I don't know?
A thought
Ron what engine is the 1/4" temp switch for -- I'll look up the part number - need a 1/4" switch.
Ken
I guess I could clip a couple of wire extensions to the temp sender and immerse it in a pan of boiling water.
Paul
Quote from: britinusa on August 18, 2015, 01:36:57 PM
I guess I could clip a couple of wire extensions to the temp sender and immerse it in a pan of boiling water.
Paul
yeah only the tip needs to be water, so leave the terminal out and clip a wire/vice grip on the hex to hold it.
Just check resistance between the block or sender in place, to the batt neg.
Batty negative is clean and on the starter bolt?
TStat housing was cleaned, 2 bolt threads cleaned, and reassembled with copper anti-seize and a biting lockwasher under the bolt head??
I think the lower part of the housing is bolted on -- could be corrosion there also.
Ken
Quote from: britinusa on August 17, 2015, 12:32:45 PM
Shorted the new sensors to the body of the sensor housing and the temp gauge read full right, and the temp alarm sounded (pretty weak!) and the light flashed.
I shorted the temperature sensor housing to the arm of the alternator support. Still no temp reading.
Paul
Paul
Since you shorted the terminal to the housing -- and the alarm worked (temp switch wire) and the gauge went high (temp sender wire) it seems that you have a good engine ground. Maybe not prefect, but at least good. I'd check the resistance of the gauge sender at the temps on the troubleshooting guide. You can use a heat gun also to bring the temp up. Also check the temp switch to see if it closes when temp goes up, as there is no telltale for that - (unlike the oil switch/alarm) you never know whether it's functioning until the engine overheats and she alarms (or not!).
Ken
Last night I checked the Connection between the engine and the main battery -ve.
Connected wire from Main Battery -ve to DMM, Connected DMM to Engine block. Resistance = 0.4 ohms
Paul
Are you sure the temperature sender is correct? The gauge requires a sender that provides 240-33 ohms for the gauge to go full scale.
Also, are you sure your engine thermostat is ok and that the engine temperature is not in fact running low?
Quote from: britinusa on August 25, 2015, 08:45:37 AM
Last night I checked the Connection between the engine and the main battery -ve.
Connected wire from Main Battery -ve to DMM, Connected DMM to Engine block. Resistance = 0.4 ohms
Paul
Paul,
0.4 - obviously your engine ground is good enough for the sender to work (very low current.)
What temp are you reading cold and 'hot'? Are you running her under load or at the dock?
Was the ambient resistance 74 ohms or 740 (about normal.)
Ground ruled out, it points to a gauge or a sender problem.
Do you have the OEM gauge, or PO did an aftermarket auto gauge?
Not having hands-on/eyes-on, it's hard to troubleshoot, but my next step might be to pick up an assortment of resistors at Radio Shack and check the gauge according to the gauge/resistance specs that I mentioned earlier that are on the Wiki site -- 75F (700 ohms), 120F (240 ohms), 212F (55 ohms), 240F (33 ohms) . Radio Shack has a set of mini-alligator cables that makes it easier for clipping resistors and testing. That might be a little easier than checking the sender? Then if gauge is ok, go the sender resistance in hot water. BUT remember everything has a +/= to it - gauge/sender up to 20%, resistors, 5% maybe 10%, your meter, thermometer for water temp maybe 10%? So add it all up and temp gauges are very approximate anyway.
Did you remove the cap and verify that there's a thermostat in installed?
Ken
After all this it would ironic if the engine was actually at minimum temperature.
I'll go down to the boat this evening.
Check the coolant temperature
Flash up the engine and let it run 10mins
Check the coolant again.
I can make a variable resistor to test the guage (the old split pencil routine)
Will try that too.
Thanks guys.
Paul
Realize that a diesel won't get to normal operating temp unless under load. Before I changed the WH setup and moved my hoses up to the thermostat bypass loop, I'd run her for an hour at the dock before I got hot water. (OEM the WH was in series with the HX). With the setup after our C30 engines, you start making hot water immediately - before the Tstat opens.