Universal Engine Overheating; Assistance Reqd

[John Martin]

Have a Universal 25 in my CD31. Engine is overheating but have good exhaust water flow.

I have performed the following but still have a problem. Any advise/assistance would be greatly appreciated.

1) Replaced impellor.
2) Good exhaust water flow before & after impellor replacement.
3) Cleaned heat exchanger. Have good water flow through exchanger "out
of boat", replaced 3 of the 4 hoses when re installing heat
exchanger. Heat exchanger is "cool" to the touch.
4) Removed thermostat to determine if it was bad.

Cranked engine and still indicating overheating. Temperature Gauge is working ok.

Next thing I will do is check out the re-circulating pump but any advise would be greatly appreciated.

John Martin



johnmartin55@hotmail.com

[len]

john

have you bled the freshwater/antifreeze side of the system? - there is a little valve to do so, right above the thermostat if i remember correctly -

len
CD 31 Sea Lion
Hingham, MA



md.frel@nwh.org

[Bob Ohler]

John,
After sending my heat exchanger out last year to be serviced and cleaned, I had the same problem. What I found was that the water/anti freeze level was too low after I thought that I had filled it. Assuming that you have a hot water heater in one of your cockpit lockers, there is probably an expansion tank there as well with a radiator cap on it. Check the level there, and see if it is low. This is where you would add your 50/50 anti-freeze / water mix. Add the solution slowly so that any potential air bubble can work its way out.
Let me know if this solves the problem.

Bob O.

john

have you bled the freshwater/antifreeze side of the system? - there is a little valve to do so, right above the thermostat if i remember correctly -

len
CD 31 Sea Lion
Hingham, MA

bobohler@chesapeake.net

[Scott]

I had the same problem same solution, freshwater low due to small leak in the hose that goes to the hot water tank causing the antifreeze in the cooling system to decrease. DO you have an overflow tank?

Scott

John,

After sending my heat exchanger out last year to be serviced and cleaned, I had the same problem. What I found was that the water/anti freeze level was too low after I thought that I had filled it. Assuming that you have a hot water heater in one of your cockpit lockers, there is probably an expansion tank there as well with a radiator cap on it. Check the level there, and see if it is low. This is where you would add your 50/50 anti-freeze / water mix. Add the solution slowly so that any potential air bubble can work its way out.
Let me know if this solves the problem.

Bob O.

john

have you bled the freshwater/antifreeze side of the system? - there is a little valve to do so, right above the thermostat if i remember correctly -

len
CD 31 Sea Lion
Hingham, MA

[M. R. Bober]

Following up on Bob's piece:

Sometimes after adding fluids to the expansion tank you must (repeatedly) bring the engine up to the hih side of the normal temperature range to force out the bubbles. You may have an air lock.
Good luck.
Mitchell Bober
RESPITE
CD330
Annapolis, MD

[Chris Scheck]

There's nothing more frustrating than an engine that runs a little hot. A few things to check ...

1) Intake screen on the keel. After a few coats of bottom paint, the holes get clogged. Use a very stiff wire brush or a drill bit to ream the holes clean.

2) Proper size hoses and elbows in the raw water supply. We had a boat that was plumbed wrong -- some of the elbows and tees were too small and they were restricting water flow.

3) Water passages in block clogged with rust and scale. Not sure what the best way is to clean them.

Hope this helps.



cscheck@aol.com

[Joe Sankey]

I have Universal M18. Don't know if this will help, but had the same problem. Went through EVERYTHING. Ended up small reinforeced hose leading from thermostat was coming unlaminated away from the wire inside; it acted like a check valve to coolant flow. Also, one suggestion the mechanic had at the time (assuming I was not thinking clearly and/or an idiot, which I make no assumption about) was possibility of thermostat going in upside down. I had replaced mine as part of the sequence to fix things, and he wondered whether I had done it wrong. Anyway, good luck. I'm guessing a bubble.
JoeSankey
CD 30 Slow Dance
Magnolia Springs, AL

Have a Universal 25 in my CD31. Engine is overheating but have good exhaust water flow.

I have performed the following but still have a problem. Any advise/assistance would be greatly appreciated.

1) Replaced impellor.
2) Good exhaust water flow before & after impellor replacement.
3) Cleaned heat exchanger. Have good water flow through exchanger "out
of boat", replaced 3 of the 4 hoses when re installing heat
exchanger. Heat exchanger is "cool" to the touch.
4) Removed thermostat to determine if it was bad.

Cranked engine and still indicating overheating. Temperature Gauge is working ok.

Next thing I will do is check out the re-circulating pump but any advise would be greatly appreciated.

John Martin

sankey@gulftel.com

[David Brownlee]

Please see Westerbeke service bulletin 195 (5 Aug 91, revised Jan 92). It recommends replacing the original 2-inch heat exchanger with a 3-inch unit (P/N # 299835). We made this switch and it cured the problem for us. See also #193, regarding alternator mounting. We'll fax these to those who need them.

Ann and David Brownlee
"Windrush"
CD 31 # 1
Havre de Grace, MD



dbrownle@sas.upenn.edu

[will parker]

Thanks for the information. I have the 2" heat exchanger on my Universal M-18. More frequently than I like I must remove it, boil it out, removing old zinc particles, and reinstall. This usually takes care of the problem until next time, which comes around too soon. I don't have access to a fax, but if you could post some or all of Service Bulletin 195, it would be very helpful. Again, thanks for the info.
Will
"Jambalaya"
CD 30

Please see Westerbeke service bulletin 195 (5 Aug 91, revised Jan 92). It recommends replacing the original 2-inch heat exchanger with a 3-inch unit (P/N # 299835). We made this switch and it cured the problem for us. See also #193, regarding alternator mounting. We'll fax these to those who need them.

Ann and David Brownlee
"Windrush"
CD 31 # 1
Havre de Grace, MD

whildenp@earthlink.net