Guest logged in.
Welcome to C&C 27 Association Online Users: 107
Navigation » C&C 27 Association » General discussion » water pump impeller »
Skin:

Current Replies for water pump impeller
 
question water pump impeller (Sailorone)
Posted: 8:03:06 pm on 4/3/2012 Modified: Never
 
You may remember I was looking for a reliable C&C. Well I think I have found it and if all goes well it will be joining the fleet in Ottawa this spring. I want to order parts before I take posession. I want to change the water impeller. How do I know what brand it is? She is a 1976 MK III with an atomic 4. Also, I want to add electronic ignition. The existing distributor is a Delco. Which is the correct kit from Moyner Marine? Thanks


Mike
Ottawa, ON

  Re: water pump impeller (carriden)
Posted: 10:55:29 pm on 4/3/2012 Modified: Never
 
Hey Mike,
The Atomic Four was produced from 1947 to 1984.  There were 3 different models of water pump used, but for the last 12 years of production all of the water pumps were supplied by Oberdorfer.  If your boat is from 1976 then the water pump is an Oberdorfer, unless some previous owner changed it.  If you are ordering replacement impellers, make sure that you buy a spare at the same time, to carry on-board.  I also recommend the Speed-Seal cover plate for the back of the pump.  Fiddling with the screws while crammed head-down in the locker is a major pain.  When I installed electronic ignition on Carriden (a 1980 boat), I used the "Pertronix Ignitor Delco 4 cylinder, Model No. 1146A" from Moyer.  This unit has been reliable and the engine has had no ignition issues in the 2 seasons since installation.  The Atomic Four is a great engine, simple and reliable.  All of the issues which I have had over the past 7 seasons have turned out to be fuel feed issues and not a problem with the engine itself.  However, those fuel feed issues can be a bugger to track down . . .
Good luck and welcome to the fraternity.

Marcus from Carriden

Mk III, Hull #847
Oakville, Ontario

  Re: water pump impeller (davidww1)
Posted: 10:04:10 am on 4/4/2012 Modified: Never
 
I ordered a Speedseal for the rear-mounted pump after having good results with the front-mounted pump (I had a closed-circuit cooling system on my A4). The rear Speedseal never sealed, despite my jumping through several hoops with Speedseal's proprietor to try to diagnose the problem. Eventually he just washed his hands of me, which I didn't appreciate.

Search "speedseal" for the full story along with a contrasting experience with Moyer Marine, who stood firmly behind their products. If you want a quick-release impeller cover (and assuming that Moyer still sells one), I'd go with the Moyer product.


David Weatherston
Towser, Toronto
C&C 27 Mk IV

  Re: water pump impeller (Sailorone)
Posted: 7:24:55 pm on 4/4/2012 Modified: Never
 
Thanks for the info. I am going to have a lot to learn about the motor. I'll get up to speed once I get my hands on it.


Mike
Ottawa, ON

  Re: water pump impeller (sony2000)
Posted: 2:48:43 pm on 4/5/2012 Modified: Never
 
Mike, I suggest changing the impeller on land or in the water this Spring. Then check that it works. Since you are new to the C&C, change the ignition after you have had sometime running the engine on the water. If it doesn't start afterwards, you will know the one and only cause!
  Re: water pump impeller (Capt’n Tom)
Posted: 8:17:39 pm on 7/3/2012 Modified: 9:49:13 pm on 7/3/2012
 
Marcus
This is my second season with "Aries" 1976 Mark III. The engine began overheating last week and I replaced the failed impeller which had all rubber wheels totally stripped. I was unable to remove all the broken pieces in the system (removed all hoses and flushed them out). The engine continues to overheat. I don't know where the cover plate is but suspect it should be removed/cleaned. Suggestions appreciated.
Tom

Tom Ellis
Aries ‘76 C&C 27
The Blue Mountains, ON



[Our Forum software is older-generation and does not give good feedback when it's digesting a post. Please give it a minute before clicking 'Submit' a second time. Duplicate post is now deleted. - Admin]
  Re: water pump impeller (sony2000)
Posted: 2:01:57 pm on 7/3/2012 Modified: Never
 
If the impellor is chewed up, then the cam or the cam screw may be doing the chewing. You can get a new and larger cam from Moyer that may help with extra cooling as well.
  Re: water pump impeller (carriden)
Posted: 1:03:08 pm on 7/4/2012 Modified: Never
 
Hey there Tom,
Sorry to hear that you are still having cooling problems.  Trouble-shooting this can require a few steps in order to narrow down the nature of the problem.  Has Aries always been a fresh-water boat?  Is there any possibility of salt-water corrosion in the cooling jacket?  But first, some basics:

1.  Since you do not state otherwise, I presume that you are now getting a reasonable flow of water out of the engine exhaust port on the stern.  If so, this indicates that the water pump is indeed working and pressurizing the cooling system.  If not, then you are simply not getting cooling water into the system in the first place.

2.  You mentioned that the rubber impeller blades had been chewed off and presumably disappeared into the engine.  It is possible that one of these pieces is blocking the flow through the cooling jacket, possibly at the 'T' fitting.  Once the water exits the water pump, a hose conducts it to the 'T' fitting in the water jacket side plate, on the starboard side of the engine.  If this fitting is blocked, then water cannot make it into the engine block proper.

3.  In a similar vein, if the thermostat is stuck shut, then the water cannot flow out of the cooling jacket.  This means that is also blocked from entering through the 'T' fitting into the engine block.  Instead, it flows through the bypass in the thermostat housing directly into the exhaust manifold and from there through the muffler and out the exhaust port in the stern, without providing any cooling.

So, if you are in fact getting reasonable amounts of water out of the exhaust port, I would start with the following steps:
1.  First, remove the thermostat from its housing, close things up and try the engine again.  If it starts cooling properly, then the thermostat needs to be cleaned or replaced.  The thermostat housing sits on top of the block at the front of the engine, with one hose coming into it from the 'T' fitting and one going out and across the front of the engine to the exhaust manifold.  The thermostat can be cleaned by soaking it in vinegar for up to 24 hours, then brushing off all of the accumulated crud.  You can then put it in a pot of water and heat the water up to verify that the thermostat actually opens when hot.  You can use a cooking thermometer to verify at what temperature it actually opens.

2.  If step 1 did not solve the problem, then you could try removing the water jacket side plate from the starboard side of the engine and check that the outlet of the ‘T’ fitting is in fact clear and allowing water to flow through.  Be gentle and patient in undoing the bolts of the side plate.  If necessary, use penetrating oil and heat to help free them up.  When replacing the plate, torque the bolts to a snug fit, somewhere around 25 ft-pounds.

If the above two steps do not restore effective cooling, then you may need to power-flush the water jacket.  This is a much more complicated procedure which is described quite thoroughly in the Moyer manual for the Atomic 4.  
Try these steps and let us know how they work out.  Remember that older ladies like our nautical mistresses require patience and gentle persuasion.

P.S.  I think that David makes an excellent point about the Moyer water pump cover vs. the regular Speed-Seal cover.  I have read the same sort of comments elsewhere.

Marcus from Carriden

Mk III, Hull #847
Oakville, Ontario

  Re: water pump impeller (Capt’n Tom)
Posted: 5:44:01 pm on 7/4/2012 Modified: Never
 
Marcus, thanks for your detailed reply/suggestions. I have just returned home after another frustrating exchange with Aries. I checked the new impeller and it looks fine. I have removed the thermostat and tightened the alternator belt which was loose. She is still overheating and very little water is exiting the exhaust pipe when the engine is operating.
I will follow your instructions tomorrow moning. I plan to remove the alterrnator to access the hose between the alternator and the engine block. I will check that hose for blockage.
Should I consider removing the side plate to check for blockage?
Tom

Tom Ellis
Aries ‘76 C&C 27
The Blue Mountains, ON

  Re: water pump impeller (admin)
Posted: 10:19:32 pm on 7/4/2012 Modified: Never
 
Marcus, love it. How'd you like to turn that into a page for Black Arts on the general subject of troubleshooting a cooling problem?

- Admin


  Re: water pump impeller: Update (Capt’n Tom)
Posted: 9:20:51 pm on 7/5/2012 Modified: Never
 
Marcus, This morning rotated alternator to allow access to side plate. Successfully removed the side plate after applying "releasall lubricant" and carefully wrenching/ratchetting off the 8 bolts. Did not find any large broken impeller pieces but did vacuum out much gritty residue from the chamber. Cleaned off the inside of the plate and cleaned out the "T" connection. No large chunks found. I have been replacing the hoses and clamps as I continue.
Tomorrow I plan to reinstall the side plate and reconnect hoses and alternator/belt.
Question: Is the length of the inlet hose from the seacock to the water pump significant? mine is 3 feet long but only travels a vertical distance of 6 inches. Should this hose be shorter?
Tom

Tom Ellis
Aries ‘76 C&C 27
The Blue Mountains, ON