So I took all of the hoses off of my motor and I'm having problems with the routing after rebuilding the coolant pump and the raw water pump. I believe it came with the hot water heater from the factory. If anyone could give me a detailed rundown of input and output for raw water and fresh water pump and the heat exchanger and the water heater I would greatly appreciate it. The big question for me actually is the transmission cooler. Is it cool with engine coolant or Raw water? Yes, I was an idiot but I thought I would be able to remember and I did remember for a while but I got sidetracked on other projects on the boat and waited too long to reassemble the coolant system. A drawing would be super helpful. Thanks in advance!
37c 3qm30 Kanzaki water house routing please help
- Thread starter Cocoa Beach Sailor
- Start date
Thank you for the reply but my engine manual doesn't seem to show the detail I need. Or I'm not looking in the right place which could be the case. THe Kanzaki ZF45-1 transmission is cooled and I cannot figure if it is in the raw water circuit or coolant circuit. Thanks again, Terry
What you are calling the "transmission cooler" is actually the engine heat exchanger. The Yanmar 3QM30 was a raw water cooled engine that Hunter converted by using a Sendure heat exchanger. The outlet of the raw water pump (port side bottom of engine) goes to the heat exchanger and from there to the exhaust elbow. I can't recall from memory the exact route of the glycol circuit but I think it goes from the top of the exhaust manifold to the hot water heater, back through the heat exchanger and returns to the engine. There is no oil cooler for the Kanzaki transmission. You'll have to get someone to take pictures of their setup for the exact hose connection points.
Note that on the 3QM30 in the H37C, the Sendure heat exchanger was mounted on the bell housing, above the transmission. On the 2QM30 I think it was a different heat exchanger mounted on the starboard side of the engine compartment. Both types of exchangers used sacrificial 'pencil anodes'.
Note that on the 3QM30 in the H37C, the Sendure heat exchanger was mounted on the bell housing, above the transmission. On the 2QM30 I think it was a different heat exchanger mounted on the starboard side of the engine compartment. Both types of exchangers used sacrificial 'pencil anodes'.
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I seem to have a much different configuration. I have the 12 vein impeller raw water pump and it's discharge hose goes back to the transmission where there is a heat exchanger and then it comes back up and goes into the engine heat exchanger which is mounted on the forward top portion of the engine and says Yanmar on it. Assuming that the transmission is cooled with raw water, I have it all figured out and it really wasn't hard at all. I thought I had thrown away the hoses but it turns out I did not. It has been an extensive time in the boat yard doing many things to a boat I bought on the hard. It appears that the discharge from the engine heat exchanger then goes to the exhaust manifold. I have a T fitting for the glycol circuit just to the left of the coolant pump that goes back to the hot water tank and then the return line, actually I have those two reversed the T fitting I would think is the return, but the other line goes to a fitting spliced in just below the temperature switch with a t. Cirrus Minor was hearkened out of The Ether in 1984 by Mystics in the Andes playing didgeridoo's.
Being that late of a year mine might be different or perhaps a newer motor was put in. Originally this boat was the Jolly Roger and it was very well kept for a long time by a gents in Titusville Florida I believe, but the two brief owners between he and I monkeyed about a good bit with a number of things.
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You are right, that is different Yanmar - 3QM30F rather than "H"? - than was standard for the 1980-83/84 H37C. Late production versions (84/85) had the Yanmar 4JHE, which was 40 HP. Perhaps your boat was re-powered at some point; afraid I can't help with that one...
Thank you much anyway, I am hoping it was a repower as the hour meter has but $3,000 on it which is not that much from what I understand but I would be interested to hear your perspective on 3000 hours for a 3qm30. It cranked right up I rebuilt the coolant pump as well as the raw water pump and I'm putting a new alternator and starter on there as well. I put a new pulley on the coolant pump to try to save belt life. I've spent a good bit of time trying to send the crank pulley smooth. I did go with a Hitachi 65 amp alternator from a Datsun and now realize a difference in belt widths between the Hitachi and the Yanmar but I will wait till I run it for a while before I go down that rabbit hole
It would seem that if that is a transmission cooler that this would be first in the cooling line. Then to the engine and then to the water heater. Final step is to go to the exhaust elbow. I picked the transmission as first only because it seemed that you would want that at a lower temp. I could be wrong on this. So it is possible that the pump water goes thru the engine first then the trans. The rest of the circuit seems normal.
Perhaps the two pages in the attached pdf will help? I scanned from Yanmar's official 2QM/3QM service manual.
Are you sure the transmission has a cooling circuit? My 2QM transmission doesn't. And looking at the 3QM both pages in the pdf, I don't readily notice any tubing routed to the transmission.
cheers,
rardi
Are you sure the transmission has a cooling circuit? My 2QM transmission doesn't. And looking at the 3QM both pages in the pdf, I don't readily notice any tubing routed to the transmission.
cheers,
rardi
It is a fresh water cooled motor. The water heater is on the fresh water side. I agree that transmission first seems likely. Since the transmission was designed with raw water only cooling in mind, it is logical that it is raw water cooled. Pump to Trns, To engine heat exchngr, to Exhst it seems. Thanks, CM
Hi, see photos above small heat Exchngr seems first in line from raw water pump then back to engine heat exchngr, then to Exst. This setup does seem to be an odd duck. I see no reference to My Zf45-1 Kanzaki anywhere. I have the heavy duty 12 vane impeller in the larger raw water pump, a much beefier trans than usual. So it seems a repower or something. Thanks
I had a Kanzaki transmission and it was not cooled at all. There may be an oil cooler. On the Yanmar 3JH2E the oil cooler is just above the transmission and is after the heat exchanger.
I do not understand. After the heart exchanger in what manner? Seeing it in person, it is dedicated to transmission. Lines from tran go into heat exchanger. Not so easily perceived from photo.
From my recent readings about Kanz Transmsns, heat X 's were optional on the zf45.