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  Topic Review (Newest First)
08-20-2007 03:43 PM
starnesent wow im learning more than i wanted to know -
but for others that are lurking for cooling related info i pass along this informative article link i "borrowed" from Northeaster water related thread
08-20-2007 03:07 PM
starnesent thanks for the good pics NOLA - ive the service manual for this A-4 & it has the open pump impeller pictured as yours is shown.
the vanes appear to be in the similar direction.
i wish the pump on this A 4 was easily seen - but its in a close quartered sail boat & yup it can be felt, but not seen.
ive gotten news from Don at moyer about the FWC kit still needing the old raw water pump in the system to pump raw water thru the cooling tank for adequate cooling to be achieved. So since i have to tackle the existing pump fix -

im going with the advice to stay with the raw water set up as its original & was working.
im just going to bite the bullet & take another trip over there & tackle the blind removal of that pump.

[I will try taking the impeller cover off first. but since it can not be seen that may not work out well enough.but i will try]

im a bit handicapped & have limited motor skills as a result of strokes [yup its a bummer] i can do it,but it just takes longer.
on a good note ive long arms to reach back there. but the large hands get in the way a little. yup whats a little skin & blood in the bilge (?) it will rinse out

the strainer is external on this boat (as far as i could find)
& i keep it clean & can blow by mouth thru the hoses to the pump.
& when i open the sea **** a nice flow comes up there.

im a bit concerned with the location of the external water strainer as its mounted (for easy access in the side boat box)
about even with the top of the engine block. so wat er must flow up from the sea **** - above the water line & then be pulled back down to the water pump.
that is the way it has been since she bought the boat around
the mid 90's & has been inspected as well as serviced by real boat professionals in the past.

im pretty sure it IS the impeller as this has never been replaced since she bought the boat. there is no signs of leakage or noise. so im hoping its only an impellor change.

If not - then i will order that new wonder MMI pump from moyer & have it nice & new.

* i might just order it before driving the 375 miles over to the boat.
a new pump installed & then take the old pump home to my shop for easy rebuild on my bench.

the boat isnt likely to be used for any real sailing as she has not sailed it yet in the time she has had it - we only motored between marinas to dock the floating apartment.

it is set up to sail with all the sails & rigging. but for some reason she dont sail.

i know i dont need to,so thats my excuse. ive only run rivers -
id not turn down an opportunity to go on a motor sailer -
but sail only is a little too limiting & small boats in the ocean do not inspire confidence in me as im unskilled & know nothing of sailing.
08-15-2007 10:44 AM
NOLAsailing The A4 raw water pump rarely fails. Check the impeller, the flow to the pump when you have the cover off the water pump (may indicate an issue with the external strainer or the seacock and associated hoses), and the internal water strainer.

If you haven't checked it yet, my money is on the impeller. Get a new impeller and gasket from Moyer Marine first - replacing the impeller annually is normal maintenance, so you might as well do it when the cover is off. Before you take the impeller out, be sure to photograph it or draw a diagram to show which way the vanes are oriented.

Just so you know what you should be looking at, the photos below are of an impeller in a water pump with the cover off and the straining basket of a water filter. They're from a Yanmar diesel, but the A4 parts will look the same.


Filter basket
08-14-2007 11:34 PM
starnesent sorry i thought i wrote it out better.
i did buy the proper Marine T Stat. yup its new & correct - many informed me that auto T stats are very different **& i agree that is easy to see}

i also tried it without the T Stat -

the pump brought a little water up to the end of the T stat housing but not enough pressure/flow to continue.

yup i replaced the hoses in hopes it might help.
& blew [by mouth pressure] to check for any blockages - (couldnt check through the pump as i didnt have a way to try that & thought that may not be a great idea to blow the wrong way thru it)

im sure guessing it needs an impeller -

but wow what a pain to even change hoses & tune up [arrgh]
i can only stand so much of the boat mech projects.

its near Seattle & im from North Idaho - so to work on it i drive over & sleep on it & crawl in & over it working on that wonderful piece of stuff every trip over there.
the sister is supposed to maintain stuff [its hers for over 10 years] but even maintaining battery fluids are neglected.
she keeps the teak oiled & anything inside thats pretty. while the rest sits unattended until im invited over.
nope i dont sail. she has not sailed it yet either.
it has been motored about marinas on occasion. but its main duty is floating temporary use as an apartment/hotel to visit.
yup its ready to sail but not motored because of the lack of cooling.

thats my next project to first be sure its the pump before i order a new one.
and then install it.

Then i will rebuild the old one & set it in there for a spare in case someone -
some day wants to sail (?)

im reasonably sure the RAW water pump has failed.
but hope to find an easy way of getting the cooling done.
thats my question about the FWC.
will the right FWC kit work without having to mess with the old RAW water pump?

im hoping the old pump can just be disconnected & the FWC system plumbed into the T stat housing & out the exhaust as the old RAW water went.
there is ample room to access the flywheel end of the engine its head & Exhaust manifold & im hoping room for the FWC holding tank on the wall right alongside for easy setup & use.
(yup im a lazyboy kind of guy) looking for the easy way to fix it & spend some more of the sisters $$ to fix a pump that could be replaced for around 200 - yup its only money -

[her money]
my knuckles

(& yes id like to have it done by someone else)
If only someone in the Puget Sound area might be interested in a dock call (?) Port Orchard (?) $$ (?)
i will meet them & open the gate & hand them tools and all with a smile

the block,head & exhaust manifold look to be in great shape. no water in the oil. no oil or water leaks in or around the engine. the bidge below the motor stays nice & clean when run at the dock
also when ive run it about the sound.
[nope i dont sail either] -only motor boats
(i dont even pretend to know how to sail) im a river boat person - im familiar with outboard jet boats & have run many hours/days with a couple out board jet units here at home but mostly on rivers in AK (yup i was a guide fer a bit)

im familiar with outboards -
but the A-4 is a simple & good design easy to see & understand,
but hard to fix in a close quartered sailboat hull. no room to crawl inside & a little too heavy/big to slide out into the cabin -
so it must be fixed in place in order to keep the pretty wood intact & the carpet nice & clean -
Very important stuff to the sister it being purty

*im 46 & the sister is -
[well gurls dont like the age known,
lets just say that she is a little older than i]
she tells me im the technical one & she is the pretty one - yup
thats accurate - ppl say she is pretty
08-14-2007 06:13 PM
rpn59 Hello,
to add to the last post: the older A-4's had passages cast into the cover plate on the water pump side of the motor and are known to scale and cause flow problems. Universal changed this and added a steel plate with a directional valve to shoot the water aft, Moyer sells these. It's not a hard project but you will have to remove the pump to bypass and bypass to t-stat lines. the alternator and bracket. I was able to get mine off without removing the starter, had to, the bolt heads were wasted. You got the right idea, take it one item at a time up stream. Oh, I highly recommend the FWC I have one in my '77 Ranger and inside of the engine and manifold was impressively not deteriorated.

Ahh, how old is your sister???
08-14-2007 05:35 PM
NOLAsailing This is a new thermostat right? Try removing the thermostat altogether (this is OK, the early A4's didn't even have one) and see if this improves the water flow.

If you are getting good flow to the thermostat, then the pump is probably fine. Check the other connections - the crossover tube between the head and the manifold and the water outlet on the manifold are common trouble spots.

If this is a raw water cooled A4, then there is a good possibility it has built up enough scale and sedimentary deposits to cause a blockage. The best way to fix this is with an acid flush. Run a 1:3 water and muriatic acid solution through the engine and then flush well with fresh water. If you can identify the blockage, you can soak the offending part in a stronger solution.
08-14-2007 02:57 PM
A-4 no water thru cooling -

yup ive a sister with a sailboat - and
yup im the fixer - even tho i prefer river runners - oh well.

its a 77 Islander with the atomic 4 gas engine & until last fall
it always worked fine.
i noticed a no flow [no water out exhaust] shut it off & began my research. the pump shows no signs of leakage & no rattles
or clunks - checked water in valve & lines. 1st cleaned valve
& replaced lines as the old looked it & were hard.
then a new t Stat replacement as water came that far but stopped (so i was hoping it was a faulty t stat) nope even without a T stat water wouldnt lift into the head : O shucks

the motor starts easy & looks nice & clean as does the outside of the water pump. [just dont pump] so im searching for an easy way out of having to change out the pump as im
6'6" & 235# & there is not much space for a mans hands to access that fine pump under all that other sail boat stuff ##

i know ppl that have FWC kits on their boats
[but they are big boats]

i see moyer has a FWC kit that appears easy to install & am in hopes it might work & actually replace the need for the salt/raw water pump & its old raw water intake.

im totally new to sail boat stuff & inboards for that matter.
i only know what ive read & learned by doing tune ups on this A-4 & a couple Volvo & chevy engines in motor boats -
[both of which were FWC closed system cooled]

so i guess im in need of instruction,directions & opinions
of whats needed to get this A-4 cooling again -
i got it starting & running great - just no water flowing ~ ~ ~

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