[C320-list] Another Perkins M30 Overheating Help Thread

[Dan Winsor]

Great news!! I hope the trip is saved and the remaining heat spike
disappears with the dock lines.
Dan

On Wed, Jun 14, 2023, 21:50 Jeff Smith via C320-list <
c320-list at lists.catalina320.com> wrote:

> Paul,
>
> Glad the system is working. One note - the diesel guys who helped me with
> my fuel issue said you lose 100 - 150 RPMs when tied up to the dock under
> load. So, your 2,950 was the equivalent of about 3,100 RPMs. I believe
> 3,600 RPM is wide open throttle for the M30. 75% of this would be 2,700,
> which is the recommended throttle level (according to several of my diesel
> head friend). So, if you were running an effective RPM load of 3,100, that
> puts you at 86% of WOT; I am not surprised the cooling system can’t keep
> up.
>
> I hope the fix continues at 2,700.
>
> Cheers,
> Jeff, #121
>
> On Wed, Jun 14, 2023 at 8:48 PM Paul Hetherington via C320-list <
> c320-list at lists.catalina320.com> wrote:
>
> > Thanks Dan.  We did try a bypass loop which didn't seem to help, but the
> > real issue seems to be that we hadn't purged the coolant system properly.
> > After flushing out the bubbles in the heating system we achieved the
> > following results (these are all under load at the dock).
> >
> > 2700 for 15 minutes stabilized at 185
> > 2850 for 15 minutes stabilized at 190
> > 2950 for 10 minutes heated up to 205 and was still going up when shut
> down
> > - not no overheat alarm!
> > 2000 for 10 minutes cooled down to 170
> > 2700 for 15 minutes stabilized at 185
> >
> > Not sure why it shot up at 2950, but our normal cruising is 2700 so until
> > we get a chance to do a full day of testing I am going on record as
> saying
> > the cooling system purge has helped.  We should have tried that much
> sooner
> > in our steps, but now we know.  For those wondering we used this from
> > Amazon:
> >
> >
> https://www.amazon.ca/dp/B01I40ZQWE?psc=1&ref=ppx_yo2ov_dt_b_product_details
> > The red fitting and the angle extension worked perfectly.  Best $30
> spent.
> >
> > Thanks to all for your very useful comments.
> >
> > Cheers,
> > - Paul.
> > ----------------------------------------------------------------
> > Paul Hetherington
> > Seasun 1994, Hull #155
> >
> > On Sat, Jun 10, 2023 at 10:14 AM Dan Winsor via C320-list <
> > c320-list at lists.catalina320.com> wrote:
> >
> > > I believe it is possible to get an air trap in the heater hoses to/
> from
> > > hot water tank. Do you think a temp short bypass loop is worth a try?
> > >
> > > On Sat, Jun 10, 2023, 10:51 Dave Hupe via C320-list <
> > > c320-list at lists.catalina320.com> wrote:
> > >
> > > > Don't  believe it is possible to "remove the raw water hose from the
> > > > exhaust elbow and run it overboard". It is a very short rubber nipple
> > > > attached to the exhaust elbow that is part of the rear rubber boot
> > > > connected to the rear of the heat exchanger tank/tube.
> > > > Dave Hupe
> > > > 1994  C320 #32
> > > > Holland,  MI
> > > > Sent from Yahoo Mail on Android
> > > >
> > > >   On Fri, Jun 9, 2023 at 9:18 PM, Dan Winsor via C320-list<
> > > > c320-list at lists.catalina320.com> wrote:   Hey all, this is a good
> one.
> > > > So.... now that we have confirmed fresh water
> > > > flow via clear hose section (great idea), let's focus on heat
> transfer.
> > > The
> > > > fresh water gains heat from circulating around the cylinders and
> dumps
> > > heat
> > > > by transferring to the raw water via the heat exchanger and the hot
> > water
> > > > heater via a coil located within. Those two circuits are parallel
> flow
> > > and
> > > > the hot water heater will get less flow due to smaller hose size.
> Does
> > > the
> > > > hot water heater get hot?
> > > > The engine heat exchanger is the primary heat dump of course.
> Although
> > I
> > > > have not had cause to open mine, I assume it to be a shell and tube
> > type
> > > > exchanger where raw water runs thru tubes from the fwd end to the aft
> > end
> > > > of the exchanger and the tubes are surrounded by fresh water being
> > > > circulated by your new engine water pump. The radiator cap being on
> top
> > > of
> > > > the exchanger shell insures that if the water level is near to the
> top
> > > then
> > > > the likelihood of airbound condition is minimal. The expansion tank
> > being
> > > > even higher pretty much guarantees it. Have you run with cap removed
> > and
> > > > seen flow thru the shell?
> > > > The wet exhaust is a good indication of raw water flow but can be
> > > somewhat
> > > > hard to differentiate good flow from low, especially with the pulses
> > from
> > > > the muffler. I would second the suggestion to resort to a contact
> > > > thermometer and start tracing the heat. I frequently grip the hose
> > > leaving
> > > > the raw water pump (cool to touch) and the hose entering the exhaust
> > > elbow
> > > > (quite warm) during my engine testing prior to launch.
> > > > Here are some additional suggestions....
> > > > 1. monitor the expansion tank and verify that level rises as engine
> > heats
> > > > and returns to prior level as engine cools. this will verify proper
> > > > operation of the radiator cap and the plumping between the cap and
> the
> > > > tank. should eliminate air concerns.
> > > > 2. when eng temp starts to climb, try running hot water and see if
> that
> > > > stabilizes or slows the rate of increase.
> > > > 3. remove the raw water hose from the exhaust elbow and run it
> > overboard.
> > > > Cob some plug on the elbow where the hose was attached. This will
> > > minimize
> > > > back pressure on the raw water pump and create more flow thru the
> tubes
> > > > thereby transferring more heat. This will also eliminate the exhaust
> > line
> > > > from being a cause. Of course exhaust flow will be louder and get
> > hotter
> > > so
> > > > don't run that way too long.
> > > > 4. remove the large rubber end caps at one or both end of the heat
> > > > exchanger and clean the inside of the tubes with a bottle brush.
> fouled
> > > > tubes cant transfer heat well.
> > > > 5. verify indicated eng water temp with contact thermometer.
> > > > Sorry if I repeated any testing you have already done. I also have
> the
> > > > perkins and have a vested interest in your issue. Lets solve this
> thing
> > > and
> > > > save your trip!
> > > > Dan Winsor
> > > > Lucky Devil #109
> > > > Mattapoisett, MA
> > > >
> > > > On Fri, Jun 9, 2023 at 1:20 PM Paul Hetherington via C320-list <
> > > > c320-list at lists.catalina320.com> wrote:
> > > >
> > > > > Jeff and Dave thanks for your comments.  Thanks for sticking with
> me
> > on
> > > > > this.
> > > > >
> > > > > Dave, you are correct we are in Salt Water and have replaced the
> > > exhaust
> > > > > elbow.  It was relatively inexpensive and easy to do so it was high
> > on
> > > > the
> > > > > list.
> > > > >
> > > > > Jeff, we may very well have air in the system it sounds like.
> After
> > > > other
> > > > > fixes we may not have been focusing on getting it all out well
> > enough,
> > > > > giving us the impression other fixes didn't work?  Going to play
> with
> > > > ways
> > > > > to eliminate it.  I'm not sure I understand the funnel method you
> > > > mention,
> > > > > but I am doing some research.  Also looking into whether a pressure
> > > > tester
> > > > > would be of value.  Dave mentioned 7psi.  Gonna chase that down.
> > > > >
> > > > > We did think perhaps we were over propped (good suggestion), but
> > after
> > > > > working with the outfit that built our prop up here in Naniamo (he
> > was
> > > > very
> > > > > helpful) it actually appears we may be under propped which is
> > resulting
> > > > in
> > > > > our not achieving expected speeds and thus wanting to push the revs
> > up.
> > > > We
> > > > > are working with that as separate issue and will be re-pitching
> > after a
> > > > > haul out in 2 weeks.  Hopefully that doesn't exasperat our
> > overheating
> > > > > issue, but at least we will be able to achieve a higher speed at
> the
> > > > lower
> > > > > rpms we are currently forced to operate under.
> > > > >
> > > > > Will report back.
> > > > > ----------------------------------------------------------------
> > > > > Paul Hetherington
> > > > > Seasun, 1994, Hull #155
> > > > >
> > > > > On Fri, Jun 9, 2023 at 8:48 AM Jeff Smith via C320-list <
> > > > > c320-list at lists.catalina320.com> wrote:
> > > > >
> > > > > > You might try running the engine without the cap on (apologies if
> > > this
> > > > > has
> > > > > > been suggested). It sounds like air in the coolant. There is
> also a
> > > > > > no-spill funnel that you can use with coolant to make sure there
> is
> > > no
> > > > > > trapped air. This involves filling the funnel with coolant and
> > > running
> > > > > the
> > > > > > engine and letting air bubble out. It might be getting into the
> > > system
> > > > > > through the cap.
> > > > > >
> > > > > > Is it also possible you are over-propped? I know you just
> > installed a
> > > > new
> > > > > > prop and the problems also just started. Either too much pitch or
> > > > size? I
> > > > > > am sure, based on the list of stuff you have replaced, that this
> is
> > > not
> > > > > an
> > > > > > issue. But, I have a max prop with adjustable pitch, and the
> > previous
> > > > > owner
> > > > > > (or me the last time I serviced it) set the pitch too low.
> > > > > >
> > > > > > Good luck. Let us know if you figure it out.
> > > > > >
> > > > > > Jeff Smith, #121
> > > > > >
> > > > > >
> > > > > >
> > > > > > On Fri, Jun 9, 2023 at 9:54 AM Dave Hupe via C320-list <
> > > > > > c320-list at lists.catalina320.com> wrote:
> > > > > >
> > > > > > > Looks based on your photos like some minor coolant leak around
> > the
> > > > > > > "radiator cap" neck on the heat exchanger tank. The cap looks
> > > > > > > original/rusty. So, wouldn’t hurt to replace it (7psi is what
> is
> > > > > spec'd).
> > > > > > > However, without seeing a trail of coolant leakage there, I am
> > not
> > > > sure
> > > > > > > that is your problem.
> > > > > > > I have heard about blockage in the exhaust elbow causing
> > > overheating.
> > > > > Any
> > > > > > > consideration of that?  I replaced my entire heat exchanger
> tank
> > > > > because
> > > > > > > the "radiator cap" neck on the tank had a piece cracked off
> where
> > > the
> > > > > cap
> > > > > > > should seal.  I had to remove my exhaust elbow attached to the
> > tank
> > > > and
> > > > > > > remount it on the new tank.  I carefully inspected my elbow and
> > it
> > > > was
> > > > > > very
> > > > > > > clean and seemed fine to reuse.  My boat has always been in
> > > > > > freshwater.  I
> > > > > > > don't see on the hull roster or your posts where you are
> located
> > > > > > > (saltwater??). That can make a significant difference related
> to
> > > > items
> > > > > > like
> > > > > > > this.
> > > > > > > Dave Hupe
> > > > > > > 1994 C320 #32
> > > > > > >
> > > > > > > Sent from Yahoo Mail on Android
> > > > > > >
> > > > > > >  On Fri, Jun 9, 2023 at 1:42 AM, Paul Hetherington via
> C320-list<
> > > > > > > c320-list at lists.catalina320.com> wrote:  So still trying
> various
> > > > > > > suggestions here and have ordered a fresh water
> > > > > > > pump.  But we put a clear hose on the fresh water loop today
> and
> > > it's
> > > > > > very
> > > > > > > obviously circulating water.
> > > > > > >
> > > > > > > We thought we had maybe fixed the overheating after really
> > running
> > > at
> > > > > > high
> > > > > > > revs the other day for testing of the prop (dislodged
> something?)
> > > so
> > > > > did
> > > > > > > some measurements/testing.  Unfortunately the temp climbed to
> 200
> > > > after
> > > > > > > about 30 minutes at 2700.  It dropped back down to 180 after 20
> > min
> > > > at
> > > > > > > 2000, and then climbed back to 185 after 30 minutes at 2500.
> Not
> > > > sure
> > > > > if
> > > > > > > it had plateaued because we had to come in.  But clearly still
> > > have a
> > > > > > > problem.
> > > > > > >
> > > > > > > Any chance a small leak in the rad cap could cause this?  Here
> > are
> > > > some
> > > > > > > pics.  We can't see  a leak, or water coming out but it looks
> > > > corroded
> > > > > > and
> > > > > > > we are trying anything at this point.  What is the best way to
> > test
> > > > > this
> > > > > > > out?
> > > > > > >
> > > > > > > Pics here:  https://photos.app.goo.gl/E83NV9cPXe6JFXXZ8
> > > > > > >
> > > > > > > We are getting pretty discouraged at this point.  The boat is
> > > usable,
> > > > > but
> > > > > > > the month long journey we have planned for this summer is going
> > to
> > > be
> > > > > > tough
> > > > > > > with 4 knots through the water.  Especially because some of the
> > > > passes
> > > > > up
> > > > > > > here can be 8 knots (really have to time it!).
> > > > > > >
> > > > > > > Thanks, Paul.
> > > > > > >
> > > > > > >
> ----------------------------------------------------------------
> > > > > > > Paul Hetherington
> > > > > > > Seasun, 1994, Hull #155
> > > > > > >
> > > > > > >
> > > > > > > On Mon, May 29, 2023 at 7:27 PM Paul Hetherington <
> paul at heth.ca>
> > > > > wrote:
> > > > > > >
> > > > > > > > Some good thoughts here. Thanks to all.  Will be trying a few
> > > > things.
> > > > > > > >
> > > > > > > > One thing that has come up, how would we best confirm the
> > non-raw
> > > > (so
> > > > > > > > fresh) water pump is working well?  There is no impeller
> that I
> > > > know
> > > > > > of,
> > > > > > > so
> > > > > > > > not entirely sure how the water is 'pushed' around the
> circuit.
> > > It
> > > > > > would
> > > > > > > > stand to reason that if this water isn't moving well then the
> > > > cooling
> > > > > > > > transfer won't be efficient and the temp would rise.  I'm
> just
> > > not
> > > > > sure
> > > > > > > how
> > > > > > > > to best test this.
> > > > > > > >
> > > > > > > > Cheers.
> > > > > > > >
> > > > > > > >
> > ----------------------------------------------------------------
> > > > > > > > Paul Hetherington
> > > > > > > > Hull 155, 1994 Seasun.
> > > > > > > >
> > > > > > > >
> > > > > > > > On Mon, May 29, 2023 at 1:08 PM Dan Winsor via C320-list <
> > > > > > > > c320-list at lists.catalina320.com> wrote:
> > > > > > > >
> > > > > > > >> Here's my two cents worth...
> > > > > > > >> If the engine can't transfer its heat to the raw water then
> > the
> > > > raw
> > > > > > > water
> > > > > > > >> would be cold when it enters the exhaust elbow. If that's
> the
> > > case
> > > > > > then
> > > > > > > >> swap out your new water pump. I don't believe in
> coincidences
> > > like
> > > > > > that.
> > > > > > > >> Dan Winsor
> > > > > > > >> Lucky Devil #109
> > > > > > > >>
> > > > > > > >> On Mon, May 29, 2023, 15:41 P.F. Ross via C320-list <
> > > > > > > >> c320-list at lists.catalina320.com> wrote:
> > > > > > > >>
> > > > > > > >> > Paul,
> > > > > > > >> >
> > > > > > > >> > Your experience sounds very much like mine.  I run at 190
> at
> > > > 2700
> > > > > > rpm
> > > > > > > >> > cruise (I have an Autoprop) and have done all the things
> you
> > > > have,
> > > > > > > >> except
> > > > > > > >> > for doing the temp testing with a non contact thermometer.
> > It
> > > > has
> > > > > > > been
> > > > > > > >> > this way for many years and over those same many years
> > > replacing
> > > > > the
> > > > > > > >> temp
> > > > > > > >> > sender has been on my list.  I figure it is the only
> thing I
> > > > have
> > > > > > not
> > > > > > > >> done.
> > > > > > > >> >
> > > > > > > >> > I watch the temp gauge like a hawk, but it has always held
> > > > steady
> > > > > at
> > > > > > > 190
> > > > > > > >> > except for once when I sucked a plastic bag into the raw
> > water
> > > > > > intake.
> > > > > > > >> So
> > > > > > > >> > at least I know my temp gauge moves!
> > > > > > > >> >
> > > > > > > >> > Frank Ross
> > > > > > > >> > Beta Wave #206
> > > > > > > >> > Naples, FL  34102
> > > > > > > >> >
> > > > > > > >> > On Mon, May 29, 2023 at 2:26 PM Dave Hupe via C320-list <
> > > > > > > >> > c320-list at lists.catalina320.com> wrote:
> > > > > > > >> >
> > > > > > > >> > >
> > > > > > > >> > >
> > > https://www.parts4engines.com/perkins-perama-m30-water-pump/
> > > > > > > >> > > This would be the engine water pump.
> > > > > > > >> > > Dave Hupe
> > > > > > > >> > > 1994 C320 #32
> > > > > > > >> > >
> > > > > > > >> > > Sent from Yahoo Mail on Android
> > > > > > > >> > >
> > > > > > > >> > >  On Mon, May 29, 2023 at 3:02 PM, Paul Hetherington via
> > > > > C320-list<
> > > > > > > >> > > c320-list at lists.catalina320.com> wrote:  Yes our M30 is
> > > > running
> > > > > > > hot.
> > > > > > > >> > > 2500 rpm = 190, much over that and it pushes
> > > > > > > >> > > over 200.  Haven't had the guts to push it right into
> > > > triggering
> > > > > > the
> > > > > > > >> > > overheating alarm (203? - not totally sure it's
> > > functioning).
> > > > > But
> > > > > > > we
> > > > > > > >> > used
> > > > > > > >> > > to be able to run at 2700 with no overheating (185-190)
> > and
> > > > now
> > > > > it
> > > > > > > >> heats
> > > > > > > >> > up
> > > > > > > >> > > very quickly.
> > > > > > > >> > >
> > > > > > > >> > > I am pretty sure I have read all the previous threads
> and
> > > > tried
> > > > > > many
> > > > > > > >> of
> > > > > > > >> > the
> > > > > > > >> > > suggestions but we are still stuck, so posting our
> > detailed
> > > > > > approach
> > > > > > > >> is
> > > > > > > >> > > only to clarify it to myself, but hoping to get some
> > > > > insight/ideas
> > > > > > > >> from
> > > > > > > >> > > your experience.
> > > > > > > >> > >
> > > > > > > >> > > Here is what we have tried:
> > > > > > > >> > >
> > > > > > > >> > >  - Checked the raw water intake and all was clear.
> > > > > > > >> > >  - Removed hose between seacock and water filter and
> > > confirmed
> > > > > > good
> > > > > > > >> > water
> > > > > > > >> > >  intake flow through seacock
> > > > > > > >> > >  - Diver conformed no obstruction from below at the
> > entrance
> > > > of
> > > > > > the
> > > > > > > >> > >  seakcock
> > > > > > > >> > >  - Topped up the coolant
> > > > > > > >> > >  - Replaced the impeller
> > > > > > > >> > >  - Replaced the thermostat (Even though the old
> thermostat
> > > was
> > > > > > > >> working
> > > > > > > >> > >  fine when I tested both of them in boiling water)
> > > > > > > >> > >  - Took out the heat changer and cleaned in a bath of
> > > muriatic
> > > > > > acid.
> > > > > > > >> It
> > > > > > > >> > >  was then very clear.  It was not that clogged up to
> begin
> > > > with
> > > > > > > >> though
> > > > > > > >> > >  - Replaced the exhaust elbow (after ordering one with
> > > current
> > > > > > > >> > downstream
> > > > > > > >> > >  tube diameter)
> > > > > > > >> > >  - Replaced the raw water hoses between the intake
> > seacock,
> > > > > > between
> > > > > > > >> the
> > > > > > > >> > >  raw water filter and the water pump with new reinforced
> > > hoses
> > > > > to
> > > > > > > >> make
> > > > > > > >> > > sure
> > > > > > > >> > >  that they are not collapsing
> > > > > > > >> > >  - Kept testing the engine in forward gear, tied to the
> > > dock,
> > > > > and
> > > > > > > >> > >  measured temperature with heat gun all over engine
> block,
> > > to
> > > > > > > >> confirm it
> > > > > > > >> > >  wasn't a gauge issue.
> > > > > > > >> > >  - When engine was ran at 2500 rpm or higher, measuring
> > > > > > temperatures
> > > > > > > >> > >  between 195 and 200 around the coolant pump
> > > > > > > >> > >  - Always seemed to have good water flow coming out of
> the
> > > > boat
> > > > > > > >> > >
> > > > > > > >> > > Right around the time we started to have overheating
> > issues
> > > > two
> > > > > > > other
> > > > > > > >> > > events happened that may or may not be related.  We
> switch
> > > > from
> > > > > a
> > > > > > > >> tired
> > > > > > > >> > and
> > > > > > > >> > > chipped 2 blade prop to a 3 blade Campbell Sailer prop
> AND
> > > the
> > > > > > water
> > > > > > > >> pump
> > > > > > > >> > > was leaking so we replaced it with this one from
> > > > parts4engines:
> > > > > > > >> > >
> > > > > https://www.parts4engines.com/perkins-perama-m30-raw-water-pump/
> > > > > > > >> > >
> > > > > > > >> > > Any help is appreciated.
> > > > > > > >> > >
> > > > > > > >> > > Cheers.
> > > > > > > >> > >
> > > > > > > >> > >
> > > > ----------------------------------------------------------------
> > > > > > > >> > > Paul Hetherington
> > > > > > > >> > > Hull 155, 1994 C320
> > > > > > > >> > >
> > > > > > > >> > >
> > > > > > > >> >
> > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > > >
> > >
> >
>