What temperature?

[hanleyclifford]

I see the cast street plumber's fitting at the back of the manifold. I recommend you do likewise at the thermostat intake and the fitting at the front of the manifold. Reversing the hoses on the manifold (The Thatch Modification) would complete the upgrade.

[Vermonstah]

Originally Posted by hanleyclifford

I see the cast street plumber's fitting at the back of the manifold. I recommend you do likewise at the thermostat intake and the fitting at the front of the manifold. Reversing the hoses on the manifold (The Thatch Modification) would complete the upgrade.

what is a "cast street plumber's fitting" and where can I find one? Does MMI carry this? if so, then I missed it in the catalog

i have seen this referenced in other threads, also by Hanley I believe, but i dont know what it is, other than preferable to a squared off fitting where debris can collect at the back of the manifold. i have already been burned by this and would like to take all preventive measures to avoid such a recurrence.

[JOHN COOKSON]

Originally Posted by Vermonstah

i have seen this referenced in other threads, also by Hanley I believe, but i dont know what it is, other than preferable to a squared off fitting where debris can collect at the back of the manifold. i have already been burned by this and would like to take all preventive measures to avoid such a recurrence.

I went with a straight barb on the manifold outlet. No more problems with KRAP plugging up a curved fitting. By the look of the pictures you might have room to do the same.
FWIW.

TRUE GRIT

[Van_Isle]

I think the pics you refer to are of my engine.

[Renegade]

Mine runs right around 160.

[Sloopdogg]

Hi,

I ran my new Moyer exchange engine at 180 degrees by using the Indigo external Thermostat housing and 180 degree thermostat. I installed a fresh water cooling kit with the new engine as well and she ran nicely 180.

Here is a photo of the engine with it installed. I circled the housing

[hanleyclifford]

Originally Posted by Sloopdogg

Hi,

I ran my new Moyer exchange engine at 180 degrees by using the Indigo external Thermostat housing and 180 degree thermostat. I installed a fresh water cooling kit with the new engine as well and she ran nicely 180.

Here is a photo of the engine with it installed. I circled the housing

Very nice installation and that alternator is an object of lust.

[Sloopdogg]

Originally Posted by hanleyclifford

Very nice installation and that alternator is an object of lust.

Ya know, here's the funny thing. The PO installed that sweet charging system but, allowed the raw water pump to leak salt water all over the back of the engine, rendering it useless... There were a few things like that...

I actually sold that boat last fall and I'm "looking" for another, bigger hole in the water... LOL

Danny

[Oldlaxer1]

Originally Posted by ndutton

For RWC engines, beyond about 160°F salt begins to leach out of solution clogging the cooling passages. I've seen manufactured RWC mixing elbows (exhaust) completely closed off with salt. The engine prefers a higher operating temperature like 180 - 190° but in the case of RWC the cooling medium can't tolerate it.

Since adding the Temp and Oil pressure warning system, I seem to be running cooler. At fast idle around 130 and at cruise just under 140. I used to run around 170. I'm guessing there is some resistance in the temp sender wire that I perhaps exacerbated while putting the Tee fitting in the block for the alarm and sender. I'll be checking that this weekend but it got me to thinking, is there any downside to running a bit cooler?

[JOHN COOKSON]

To check the sending unit wiring for resistance: Disconnect the wire at the sending unit and the gauge. Run a jumper wire from one end of the wire with the other end near the other end of the sending unit wire. Measure the resistance. It S\B zero ohms.
To check the sending unit for grounding: One ohm meter probe on the body of the sending unit and one probe on battery ground. Use a jumper wire from battery ground to the vicinity of the sending unit if necessary.

TRUE GRIT

[Oldlaxer1]

Originally Posted by JOHN COOKSON

To check the sending unit wiring for resistance: Disconnect the wire at the sending unit and the gauge. Run a jumper wire from one end of the wire with the other end near the other end of the sending unit wire. Measure the resistance. It S\B zero ohms.
To check the sending unit for grounding: One ohm meter probe on the body of the sending unit and one probe on battery ground. Use s jumper wire from battery ground to the vicinity of the sending unit if necessary.

TRUE GRIT

Hmm, now I'm wondering if perhaps I used the dreaded conductivity killer teflon tape when screwing the Tee back into the block. I can't recall and can't find a picture of my work. Oh well, just another excuse to spend the day at the boat this weekend!

update, I did find a picture and see no evidence of teflon tape.
Thanks John

[edwardc]

Teflon tape will not affect the conductivity of the fitting. When the fitting is tightened, it cuts the tape into little spiral strips where the thread faces touch. These strips are then packed down onto the thread valleys, sealing them off. But the thread faces of the fitting and the substrate are in hard metal-to-metal contact. You can see this when you undo a taped fitting and the tape has been reduced to strings.

[2dogsnight]

Originally Posted by Sloopdogg

Hi,

I ran my new Moyer exchange engine at 180 degrees by using the Indigo external Thermostat housing and 180 degree thermostat. I installed a fresh water cooling kit with the new engine as well and she ran nicely 180.

Here is a photo of the engine with it installed. I circled the housing

I am going to run mine on sea water this season, and if the motor and the boat will perform to my satisfaction then I think will be smart to go with water cooling kit

[ndutton]

Originally Posted by Oldlaxer1

Since adding the Temp and Oil pressure warning system, I seem to be running cooler. At fast idle around 130 and at cruise just under 140. I used to run around 170. I'm guessing there is some resistance in the temp sender wire that I perhaps exacerbated while putting the Tee fitting in the block for the alarm and sender.

I think the difference is because of the Tee. The gauge sender is farther away from the flow than it used to be skewing the reading.

[Oldlaxer1]

Originally Posted by ndutton

I think the difference is because of the Tee. The gauge sender is farther away from the flow than it used to be skewing the reading.

Interesting. So 140 is the new 170 for us old guys? (Just kidding, I'm only 160)

[GregH]

Ok, let's see if I have this correct...

-The engine prefers to be about 180-190F
- for raw water cooled should be below 160 DUE to potenial precipitates at higher temp

Since I'm sailing in the Great Lakes, running at the higher 180-190 range is preferrable yes?

[Sam]

I have an early model 1966 A4 with early model thermostat and it always run at 140 F w/ Lake Michigan water. Every few years I might suck up some debris by the dock and the short 3/8 cooper tube from the water pump to the intake gets a little clogged and the temp moves up to 160 -180 F. I remove and clear the tube and gently run a coat hanger wire in and out of the respective engine intake water jacket, reassemble and it's back to 140 F.

[GregH]

Up Until Aug/Sept was running with Thermostat and no bypass valve. Engine was typically 180-185F. This is in lake Ontario waters that may get up to 70F in the peak of summer.

Switched over to no thermostat and bypass valve and the temp doesn't even make the needle move, even fully open in bypass mode.

Going to toss the thermostat back in, in the spring and see if cannot get the temps back up and the gauge showing this to make sure the sender is working. Then we'll try things again.

IF... if I find the temp send and gauge are working fine and due to the cold lake I cannot get the temps up over 120, would it be valid to run with the thermostat in AND adjust the bypass valve so more goes through the block? I am assuming that once the thermostat opens, it does block the bypass 100%

[JOHN COOKSON]

Originally Posted by GregH

IF... if I find the temp send and gauge are working fine and due to the cold lake I cannot get the temps up over 120, would it be valid to run with the thermostat in AND adjust the bypass valve so more goes through the block? I am assuming that once the thermostat opens, it does block the bypass 100%

Yes, this is what I do.
Each RWC engine is a bit difference due to the amount of corrosion in the water passages and other factors that affect water flow such as pump output and so on.
My particular engine is happy with a thermostat and a bypass value wide open. The restriction provided by the thermostat and the (wide open) bypass valve + pump output + amount of water passage corrosion ++ all balance each other.


TRUE GRIT

Edit: Do an acid flush and get the water passages as clean as possible.

[Capngeo]

Well, I’Ll be

[Capngeo]

Out of the blue the A$ acted up. She would rev up and sound great between 600-2700 rpm, but ingear all i could get was 5.5 K at 1300 RPM. Advancing the throttle over 1300,and she's run rough,and sounded like she was really struggling...so I backed off. I put my hand on the block and something didn't feel right.

[Capngeo]

a few more photos

[Administrator]

Aside: One of the images includes a great shot of the proverbial UHS.

Bill

[Ando]

Originally Posted by Mo

I just got back from the club. A member on this forum had a problem with his C&C 29, she had markedly reduced water discharge with lots of steam; Temp between 160 and 180. His son is visiting from 1000 miles away and they wanted to go out....so I went right down to see the problem.

1. Checked the water intake...clear.
2. Pulled the cover off the impeller to see if it was intact...it was fine.
3. Removed the thermostat...stuck closed.

Mine RWC (with bypass open) fluctuates between 145 and 175 at idle and I have a brand new thermostat from MM. I assumed the reason it fluctuates is bc the valve opens and closes? You think it would be safe to close the bypass and run it cool for the season and track down the blockage in the winter?

[JOHN COOKSON]

Could be the temp sending unit.
The last time I took my temp sending unit out I found two problems: (RWC engine)
The sending unit was coated with a hard water type scale. Lime away and a tooth brush removed it.
There was a lot of KRAP in the sending unit port. I threaded a nipple into the port, hooked a piece of tubing to it, started the engine and blew it out.

Could be a wiring problem sending unit -> gauge.
Disconnect the present wire and run a temporary jumper wire sending unit -> gauge and see if anything changes.

More if I think of anything else.

ex TRUE GRIT