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Sebastian
 
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Default Universal 18 with low RPM, black smoke, runs hot (over 200) after many hours

Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs (always,
although it ranges between 1750 and 2000 at full throttle), and always
give off some black smoke. Additionally, it appears that there may be
a tiny bit of black oil leaking behind the transon of the boat, but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend
some easy things to check/fix. I've heard black smoke means injectors,
but could that also cause the low RPMs?

Thanks!
  #2   Report Post  
Dan Best
 
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Default Universal 18 with low RPM, black smoke, runs hot (over 200) aftermany hours

Hi Sebastian,
Someone else will have to help you w/ re. the black smoke/oil, but if
you're boat has fresh water colling, pull and open up the heat
exchanger. Frequently, a scale builds up in the raw water side that
over time, both reduces the flow of raw water and acts as an insulator,
inhibiting the heat transfer. Put it in a bucket and fill the heat
exchanger with straight Lime Away (available in the cleaning section of
most grocery stores) or similar product. When the foaming/fizzing
stops, flush with water and you've likely fixed the problem for a buck
(the stuff is really cheap).

If you've got raw water cooling, this same scale can build up blocking
the passages in the engine block. This is a bit more involved to clear
out. Some people use a mild or very mild acid solution (diluted muratic
or acetic), but I suspect the same product would work here too.

Good luck - Dan Best

Sebastian wrote:
Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs (always,
although it ranges between 1750 and 2000 at full throttle), and always
give off some black smoke. Additionally, it appears that there may be
a tiny bit of black oil leaking behind the transon of the boat, but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend
some easy things to check/fix. I've heard black smoke means injectors,
but could that also cause the low RPMs?

Thanks!


--
Dan Best - (707) 431-1662, Healdsburg, CA 95448
B-2/75 1977-1979
Tayana 37 #192, "Tricia Jean"
http://rangerbest.home.comcast.net/TriciaJean.JPG

  #3   Report Post  
Dan Best
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) aftermany hours

Hi Sebastian,
Someone else will have to help you w/ re. the black smoke/oil, but if
you're boat has fresh water colling, pull and open up the heat
exchanger. Frequently, a scale builds up in the raw water side that
over time, both reduces the flow of raw water and acts as an insulator,
inhibiting the heat transfer. Put it in a bucket and fill the heat
exchanger with straight Lime Away (available in the cleaning section of
most grocery stores) or similar product. When the foaming/fizzing
stops, flush with water and you've likely fixed the problem for a buck
(the stuff is really cheap).

If you've got raw water cooling, this same scale can build up blocking
the passages in the engine block. This is a bit more involved to clear
out. Some people use a mild or very mild acid solution (diluted muratic
or acetic), but I suspect the same product would work here too.

Good luck - Dan Best

Sebastian wrote:
Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs (always,
although it ranges between 1750 and 2000 at full throttle), and always
give off some black smoke. Additionally, it appears that there may be
a tiny bit of black oil leaking behind the transon of the boat, but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend
some easy things to check/fix. I've heard black smoke means injectors,
but could that also cause the low RPMs?

Thanks!


--
Dan Best - (707) 431-1662, Healdsburg, CA 95448
B-2/75 1977-1979
Tayana 37 #192, "Tricia Jean"
http://rangerbest.home.comcast.net/TriciaJean.JPG

  #4   Report Post  
Leanne
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) after many hours

It looks like you are pushing too hard making it smoke. I would
check the engine manual and see and check maximum sustained RPM.
If the boat is new to you, someone may have put on a propeller
that has too much pitch and it is working the engine hard.

Leanne
s/v Fundy

"Sebastian" wrote in message
om...
Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs

(always,
although it ranges between 1750 and 2000 at full throttle), and

always
give off some black smoke. Additionally, it appears that there

may be
a tiny bit of black oil leaking behind the transon of the boat,

but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots

in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone

recommend
some easy things to check/fix. I've heard black smoke means

injectors,
but could that also cause the low RPMs?

Thanks!



  #5   Report Post  
Leanne
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) after many hours

It looks like you are pushing too hard making it smoke. I would
check the engine manual and see and check maximum sustained RPM.
If the boat is new to you, someone may have put on a propeller
that has too much pitch and it is working the engine hard.

Leanne
s/v Fundy

"Sebastian" wrote in message
om...
Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs

(always,
although it ranges between 1750 and 2000 at full throttle), and

always
give off some black smoke. Additionally, it appears that there

may be
a tiny bit of black oil leaking behind the transon of the boat,

but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots

in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone

recommend
some easy things to check/fix. I've heard black smoke means

injectors,
but could that also cause the low RPMs?

Thanks!





  #6   Report Post  
Larry W4CSC
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) after many hours

Sounds to me like it's trying to turn way too much screw at way too
much pitch. How fast will it run in neutral with no load? Does it
smoke like hell with no load?

Overloaded diesels, especially simple, naturally-aspirated diesels,
smoke like hell, ugly clouds of black smoke caused by unnatural
burning in a cylinder that's pressing too hard back on the fire above
it, producing lamp black (carbon).....soot! As it will run out of
oxygen on each burn because the load is choking the hell out of it and
it can't breathe, unburned fuel oil is also unceremoniously dumped out
the stack into the waterbox....and waterway.

Just my silly opinion from years of diesel ownership...(c;
It's only 18 HP, right?


On 8 Mar 2004 15:37:41 -0800, (Sebastian)
wrote:

Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs (always,
although it ranges between 1750 and 2000 at full throttle), and always
give off some black smoke. Additionally, it appears that there may be
a tiny bit of black oil leaking behind the transon of the boat, but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend
some easy things to check/fix. I've heard black smoke means injectors,
but could that also cause the low RPMs?

Thanks!



Larry W4CSC
POWER is our friend!
  #7   Report Post  
Larry W4CSC
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) after many hours

Sounds to me like it's trying to turn way too much screw at way too
much pitch. How fast will it run in neutral with no load? Does it
smoke like hell with no load?

Overloaded diesels, especially simple, naturally-aspirated diesels,
smoke like hell, ugly clouds of black smoke caused by unnatural
burning in a cylinder that's pressing too hard back on the fire above
it, producing lamp black (carbon).....soot! As it will run out of
oxygen on each burn because the load is choking the hell out of it and
it can't breathe, unburned fuel oil is also unceremoniously dumped out
the stack into the waterbox....and waterway.

Just my silly opinion from years of diesel ownership...(c;
It's only 18 HP, right?


On 8 Mar 2004 15:37:41 -0800, (Sebastian)
wrote:

Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs (always,
although it ranges between 1750 and 2000 at full throttle), and always
give off some black smoke. Additionally, it appears that there may be
a tiny bit of black oil leaking behind the transon of the boat, but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend
some easy things to check/fix. I've heard black smoke means injectors,
but could that also cause the low RPMs?

Thanks!



Larry W4CSC
POWER is our friend!
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Lloyd Sumpter
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) after many hours

On Mon, 08 Mar 2004 15:37:41 +0000, Sebastian wrote:

Our 1986 Catalina 27 with Universal 18 diesel tends to run hot (although not
immediately, takes many hours), has low RPMs (always, although it ranges between
1750 and 2000 at full throttle), and always give off some black smoke.
Additionally, it appears that there may be a tiny bit of black oil leaking
behind the transon of the boat, but not a lot. Finally, we get a maximum speed
of 4 1/2 or 5 knots in still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend some easy
things to check/fix. I've heard black smoke means injectors, but could that also
cause the low RPMs?

Thanks!


I'm QUITE familiar with Universal diesels, having messed with one for 15 years
before replacing it myself. As others have said, sounds very much like too much
prop. Try full-throttle at idle: what does the tach say? Also, you should
calibrate the tach if you're going to be doing any tests - a "hand tach" is a
valuable investment for a wonky diesel.

That engine should reach 3000 rpm full-throttle in neutral ("high idle"). It
should also reach close to 3000 (say at least 2700-2800) at full throttle under
load ("WOT"). I'd guess it should have about a 14x7 prop (14" dia, 7" pitch),
at most. It should be stamped on the prop (usually 14x7x1RH)

Other things to check: How easy is it to turn the shaft manually when in
neutral? Does the shaft turn while under sail? If not, maybe it's jamming,
causing too much load.

Then again, there could be a problem with the engine. Is it hard to start? Is
there smoke when running in neutral? It's a pretty simple engine: have the
injectors and high-pressure pump checked, then compression. Hope it's the
injectors - the other problems are major $$.

Yes, with the proper prop you should get hull speed with that engine, cruising
at 5 or so at 2400rpm, hitting 6.5 WOT.

Lloyd Sumpter
"Far Cove" Catalina 36 - brand-new M25XPB

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Lloyd Sumpter
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) after many hours

On Mon, 08 Mar 2004 15:37:41 +0000, Sebastian wrote:

Our 1986 Catalina 27 with Universal 18 diesel tends to run hot (although not
immediately, takes many hours), has low RPMs (always, although it ranges between
1750 and 2000 at full throttle), and always give off some black smoke.
Additionally, it appears that there may be a tiny bit of black oil leaking
behind the transon of the boat, but not a lot. Finally, we get a maximum speed
of 4 1/2 or 5 knots in still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend some easy
things to check/fix. I've heard black smoke means injectors, but could that also
cause the low RPMs?

Thanks!


I'm QUITE familiar with Universal diesels, having messed with one for 15 years
before replacing it myself. As others have said, sounds very much like too much
prop. Try full-throttle at idle: what does the tach say? Also, you should
calibrate the tach if you're going to be doing any tests - a "hand tach" is a
valuable investment for a wonky diesel.

That engine should reach 3000 rpm full-throttle in neutral ("high idle"). It
should also reach close to 3000 (say at least 2700-2800) at full throttle under
load ("WOT"). I'd guess it should have about a 14x7 prop (14" dia, 7" pitch),
at most. It should be stamped on the prop (usually 14x7x1RH)

Other things to check: How easy is it to turn the shaft manually when in
neutral? Does the shaft turn while under sail? If not, maybe it's jamming,
causing too much load.

Then again, there could be a problem with the engine. Is it hard to start? Is
there smoke when running in neutral? It's a pretty simple engine: have the
injectors and high-pressure pump checked, then compression. Hope it's the
injectors - the other problems are major $$.

Yes, with the proper prop you should get hull speed with that engine, cruising
at 5 or so at 2400rpm, hitting 6.5 WOT.

Lloyd Sumpter
"Far Cove" Catalina 36 - brand-new M25XPB

  #10   Report Post  
Matt Colie
 
Posts: n/a
Default Universal 18 with low RPM, black smoke, runs hot (over 200) aftermany hours

Sabastian,
First don't put a real @ddress out on the usenet anymore. The spambots
will take over your inbox.

The subject at hand.
I saw the thread start and did not have time to jump in early, but no
matter. Lloyd gave you a really good start and most of the information
in the thread is pretty good.

You give no clue what machanical ability you have available. But, don't
go messing with the injection pump until you have to.

I like his plan a lot, (like he said)
run it up in neutral it should get to 3k
If it doesn't, or if it smokes a bunch doing that - pull injectors first
(cheapest-easiest thing) and get them checked. One injector with a bad
spray pattern will cause all manner of grief.

Good Luck Guy
Matt Colie - 40+years at taking care of someone's engine.

Sebastian wrote:

Our 1986 Catalina 27 with Universal 18 diesel tends to run hot
(although not immediately, takes many hours), has low RPMs (always,
although it ranges between 1750 and 2000 at full throttle), and always
give off some black smoke. Additionally, it appears that there may be
a tiny bit of black oil leaking behind the transon of the boat, but
not a lot. Finally, we get a maximum speed of 4 1/2 or 5 knots in
still water, which seems to be too little...

I am quite new to diesels, so know very little. Can someone recommend
some easy things to check/fix. I've heard black smoke means injectors,
but could that also cause the low RPMs?

Thanks!


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