Reduced engine heat to hot water heater & Kubota dealers in CA

Stu Jackson · August 22, 2006, 09:20:04 PM

Situation: The metal connectors between the hoses coming from the thermostat to the larger hoses going from the engine compartment down and under the galley sole to the hot water heater under the galley sink on our Mark I had somehow loosened up. There was clear (dirty!) evidence of water seepage at the metal joints because of a film or streaks running down both hoses. I removed the smaller hoses from under the thermostat housing, didn't lose more than less than 5 ounces of coolant, and tightened the fitting between the two hoses (both supply and return). I also then burped the fresh water cooling system by opening the valve on the top of the thermostat when the engine was hot - no evidence of air in the system. The manifold is full of coolant as is the overflow tank (ala Ron's design).

Issue: The water heater isn't putting out as much heat for hot water after running the engine as we normally do for our 40 minute motor out of the Oakland Estuary to the Bay. I've been doing this for over eight years, and the water is just not as hot as it always (always) used to be. I would estimate only half as warm as usual, or a bit less.

Any ideas?

PS (added 8/23 -- I suspect the thermostat)
PPS -- engine temp is fine

David Sanner · August 23, 2006, 01:16:20 AM

Off the top of my head I'd say you either have air trapped in the system or
your thermostat isn't closing all the way. (how's the engine temp?)

Have you tried slowly burping the system while the engine is running?
(Just cracking the the valve at the thermostat housing, letting some
coolant leak out along with any air that's moving through the system)

Either that or something is plugging the system. Time for a flush?

Gary · August 23, 2006, 06:54:27 AM

Stu,

Would it be helpful in diagnosing the problem to bypass the water heater intake and outlet with a piece of clear plastic tubing? At least that way you could observe flow rate and air bubble blockage.

Footloose · August 23, 2006, 02:37:16 PM

Stu,

Last year when we purchased our C34 we didn't get much in the way of hot water either. I replaced the thermostat and it took care of the problem.

Whenever my car isn't putting out as much heat as it should I replace the thermostat and it resolves the problem. I wouldn't pay much attention to the temp gauge. At least on my car the gauge will barely be reading any lower but the difference in heat output is remarkable.

Winters here in Vermont are tough on sailling. The water is in the wrong phase. I haven't tried iceboating yet.

Stu Jackson · August 23, 2006, 03:28:58 PM

I agree, and thanks. Next ?:

I purchased a new thermostat this afternoon. The old T # (Universal) was 301358 (8 years old). The new "kit" which includes the gasket, is a #200218, and the thermostat plastic bag has this # on it, so I don't think it was just a change in the product # to include the gasket. The salesperson noted that Universal had changed the product # after checking on his computer. The new T is a little wider in diameter at the flange and not as deep.

Anyone have any recent experience on this product # change and T size? I have the puppy in my hot little hands and am prepared to put it in, just want to know if anyone's had this experience, and if you know if it fits. I'm fully prepared to try it out (not a hard job, at any rate), but it'd be nice to know that it will fit in the hole!

Ron Hill · August 23, 2006, 05:21:24 PM

Stu : As I advised an owner yesterday, take the old thermostat and go to your Kubota dealer and get the same one for less than 1/2 the Universal price.
Universal may have two thermostat housings now that they've gone to a switch and a sender for the water temperature on the newer engines - I don't really know?

Stu Jackson · August 23, 2006, 06:10:25 PM

I know, I know, I know, about going to the Kubota dealer. However, the average distance to the closest ones to me is 33 miles. A round trip of 66 miles with the price of gas today would cost more doing that. I "googled" Kubota and found them, but unless I'm doing a major overhaul or buying a ton of spare parts for an extended cruise (don't I WISH

), the cost of the journey (and my time) just isn't worth it.

For those in the Bay Area, they're in Livermore, Rio Vista and Fairfield.

Team Power
Approximate distance from your zip code: 30 miles
2034 Research Drive
Livermore, CA 94550
Phone: (925) 443-7600
Fax: (925) 443-1635
Email: dwalker@teampowerforklift.com

As of 5/7/2011 this number has been reported to be out of service.

Green Valley Tractor
Approximate distance from your zip code: 33 miles
I-80 & Abernathy Rd. - 4135 Abernathy Rd.
Fairfield, CA 94534
Phone: (707) 425-8933
Fax: (707) 425-8034
Email: sales@greenvalleytractor.com

Dolk Tractor Company
Approximate distance from your zip code: 37 miles
242 North Front St.
Rio Vista , CA 94571
Phone: (707) 374-6438
Fax: (707) 374-6430
Email: info@dolktractorcompany.com

I did bring the old one in, hence my post. I'll try the 'stat they gave me, if it doesn't fit, I'll try it again.

Craig Illman · August 23, 2006, 07:35:48 PM

The new housing for the temp sender and alarm is the same size, it just has an additional threaded hole for the alarm. I could have just taken the old housing and drilled and tapped for the alarm sender. My shop is always missing just the right tool, even after almost forty years of accumulating stuff.

Craig

Randy Stolze · August 24, 2006, 05:16:44 AM

Stu,

This probably too late at this point but being retired and frugal, I would test the orginal thrmostat in a pot of water on the stove to see waht happens at 159 degrees. Getting all of the air out of that water heater loop can be a real pia.

Regards,

Randy

Andrew Harvey · August 24, 2006, 06:56:27 AM

When I rebuilt my water pumps 2 years ago I had a heck of a time bleeding the coolant system. A mechanic friend told me to run the engine but leave the rad cap off till the T stat opens and you can see a good flow in the manifold. This actually worked and cleared out all of the air bubbles.

Tom Glennon · September 01, 2006, 11:26:58 AM

I had a similar situation after installing a new Raritah hot water heater. I disconnected the hoses as at the block, then slowly poured antifreeze in one hose, using a funnel, untill clear antifreeze was at the top of the other hose.... reconnected, and then ran the engine, opening the pet-cock on the thermostat. It did burp a little. I found after all that, I had to replace the thermostat (got the Kobuta one) and it was like magic! Engine temp was perfect, and the hot water has never been so good, even after a short engine run, it is steaming! Engine temp is a steady 160 degres too. Hope this helps.

Stu Jackson · September 18, 2006, 10:05:29 AM

On Saturday we checked the thermostat again. When up to operating temperature, the pet cock on the top of the thermostat housing didn't emit much of anything, leading me to believe the thermostat should be replaced. Previously when I had to burp the fresh water, opening the pet cock got coolant bubbles, a burst of air then steady coolant. This time, not much of anything. We tried Andrew's idea with the coolant cap off. With the engine temp OK, we still got no hot water.

I called one of the local Kubota dealers (Livermore) this morning and ordered two thermostats and gaskets. The Universal thermostat cost was $42 (for the one that doesn't appear that it will fit). The local Kubota price was $16.72!!! OK, OK, Ron and the rest of you have been right all along. I tried the tractorsmart.com reference in this thread: http://c34.org/bbs/index.php?topic=978.0 online, but didn't see the Kubota D850 series, so called locally. BTW, Bernd's model numbers for the thermostats and gaskets for his M25XP (D950) are the same as for our D850 (M25) noted in that thread. I got to that thread by doing a search on "D850." They're supposed to be drop shipped from Kubota tomorrow, I'll keep you posted.

One other thing I think remembered from earlier posts: when the thermostat stops working the engine temperature remains low -- am I remembering that correctly?

jmnpe · September 18, 2006, 09:58:34 PM

Stu,

The thermostat can "stop working" either way: stuck open or stuck closed. If it sticks open, the engine has to work hard to get up to temperature.

My previous experience with getting a bubble of air in the water heater engine coolant loop out were, as previously advertised, a real PIA. The engine looked full of coolant, and the temperature was good, but no hot water flow through the engine coolant loop to the water heater ( hence, no hot water...). I finally tried reving the engine pretty fast a series of times in neutral, and there was finally a big "blupe!" out of the open radiator cap, and it was good after that. I also had to do the same thing on the Stamas 44 when I replaced the water heater, so it must be a fairly common occurance.

John

Stu Jackson · September 20, 2006, 12:36:48 AM

Received the new thermostats today (Tuesday, 9/19/06). These match the shape of the original ones. Looks like a "GO" and I'll return the Universal one I bought from Seapower to them, and save $42 - $17. Not a bad deal for a telephone call. The new gaskets are made of a black material - could be paper,too - as compared to the older gaskets which just looked like thick paper or cardboard stock, tan like a shopping bag. These new ones also have a tiny little lip in the ring.

Ron Hill · September 20, 2006, 06:37:11 PM

Stu : If you have a stuck thermostate CLOSED, you'll have hi engine temp in short order of about 10 minutes!!

If you have a thermostate stuck OPEN, it'll take the engine much longer to get up to 160 degrees operating temp - hence it'll take longer to get hot water in the heater. However, if you motor for over an hour I'd guess the the engine temp would be OK in 20 minutes and you'd have hot water in an hour.

If after 1 hour of motoring and you don't have hot water, I'll guess that you've got some kind of blockage in the internal coolant lines??