Universal diesel multiple sudden symptoms

Jun 11, 2004
1,621
Oday 31 Redondo Beach
This is a bit out there but at 75 degrees the sea water temperature at Dana Point is about 5 degrees higher than normal for this time of year. I know when the sea water temps are up my engine heats up faster. That doesn't affect your other symptoms but is just something to consider in the mix.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
The elbow was new in July 2011.
About 350 engine hours ago.
Still looks new outside (pic taken just now), but I had opened up the side cap and hello it's stuffed with salt and junk.
I'll have it off shortly and scrape out, or replace. $180 at Toad.
2 hoses and the input pipe. Shouldn't kill me. Uh huh.
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May 17, 2004
5,032
Beneteau Oceanis 37 Havre de Grace
The elbow was new in July 2011.
About 350 engine hours ago.
Still looks new outside (pic taken just now), but I had opened up the side cap and hello it's stuffed with salt and junk.
I'll have it off shortly and scrape out, or replace. $180 at Toad.
2 hoses and the input pipe. Shouldn't kill me. Uh huh.
View attachment 154982
So any thoughts on why the elbow clogged in just 7 years? From the anecdotes I've seen that wouldn't be too bad for a Yanmar, but the Universal design seems to be more resilient. Much time idling?
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
So any thoughts on why the elbow clogged in just 7 years? From the anecdotes I've seen that wouldn't be too bad for a Yanmar, but the Universal design seems to be more resilient. Much time idling?
Nope. But generally run at 2200 rpm which is on the low end of rec cruise range. I like getting .3 gph. And that's 5.5 knots.
Might have to up it, depending on how big a pain fixing it will be :)
 
Jan 27, 2008
3,045
ODay 35 Beaufort, NC
Make a new exhaust system from schedule 80 pipe. Use a T fitting for water injection. Those elbows from Yanmar stink in comparison. My original exhaust was welded pipe with a water injection tube welded in. Lasted for 20 years. Then I used an injection elbow and had nothing but trouble . Replaced it with schedule 80 pipe, way better.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
Well that wasn't it.
I was wrong.
Took off elbow. Clear. Ran water through the jacket and the exhaust path. Jets. No obstruction. Turned water up, no backup. Free flow.
Pic shows thin black layer that's it.

Cleaned air filter. Was saturated with oil from breather. But would a diesel heat up like it did with clogged air? Maybe the bogging but heat? Gas yeah but diesel....

Also checked HX. Clear. Full water flow through both sides. There's nothing wrong with the cooling system or exhaust.

Took out 3 quarts of coolant to rem elbow and flange. Rated capacity.
Fresh water pump is 3 years old.
Raw side great raw flow out the back.

Spun the prop shaft on neutral. Free.

Just had bottom and prop cleaned, so am eager to test. 1 week for gasket delivery.

I busted the flange gasket so can't run it till my order comes in. BTW that gasket breaks when you remove /replace the flange. Luckily I hadn't put coolant back in yet. Just enough left in the rear of the manifold to show me the leak when I put flange/elbow back on.

I'm guessing it was a combination: light tube worms on the prop, high ocean-water temps now, clogged air filter.

Maybe @mainesail the Universal guru knows why M18 motor suddenly wouldn't reach past 2200rpm, and was heating fast. A phenomenon which has never happened in the 7 years I've owned the boat.
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weinie

.
Sep 6, 2010
1,297
Jeanneau 349 port washington, ny
Your problem is fuel. Your engine isn't getting it but you want to think it has something to do with the cooling system.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
Your problem is fuel. Your engine isn't getting it but you want to think it has something to do with the cooling system.
Racor clear. Just light Chablis in there. Filter recent. Took hose off just before secondary spin on, hose shot fuel into the coffee can when lift pump on. Secondary has always been new-clean when I changed it.
There's no smoke.
If lacking fuel it would have to be the injector pump or injectors. The injectors are gold so must be original 1984.
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weinie

.
Sep 6, 2010
1,297
Jeanneau 349 port washington, ny
You need to change the filter element. Looking at the fuel water separator bowl means nada.
You also need to check the lift pump filter and check for a pickup screen on the fuel intake in the tank as well as replacing the secondary filter.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
You need to change the filter element. Looking at the fuel water separator bowl means nada.
You also need to check the lift pump filter and check for a pickup screen on the fuel intake in the tank as well as replacing the secondary filter.
Thanks but I just explained that the filters are recent, and tested fuel flow is good. Fuel flow from that lift pump, which is behind the Racor in line so the fuel is filtered, is drastically more than this little 577cc motor could ever consume.
The secondary fuel filter is highly unlikely to be clogged, given its recent installation and history of cleanliness when changed.
But you never know, filter might be faulty.
 

weinie

.
Sep 6, 2010
1,297
Jeanneau 349 port washington, ny
You could check the most likely causes first or you could start tearing the engine apart replacing injectors and the fuel pump. Your boat, your rules. Keep us updated.
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
You could check the most likely causes first or you could start tearing the engine apart replacing injectors and the fuel pump. Your boat, your rules. Keep us updated.
Which I've done, apparently.
Not first rodeo. I've posted this problem because its cause is elusive.
 
Last edited:
Jan 27, 2008
3,045
ODay 35 Beaufort, NC
How about the fresh water pump? At over 30 years old maybe that is losing efficiency?
 
Dec 29, 2008
805
Treworgy 65' LOA Custom Steel Pilothouse Staysail Ketch St. Croix, Virgin Islands
Prop + batteries = low rpm in gear
Batteries = not quite as low out of gear
Les, please explain. How do the batteries come into play? Assuming a diesel with a mechanical lift pump. Doesn't need any electrical to run at all, so I'm not following how batteries would be a factor one way or the other.

Brian
 
Oct 9, 2008
1,739
Bristol 29.9 Dana Point
Les, please explain. How do the batteries come into play? Assuming a diesel with a mechanical lift pump. Doesn't need any electrical to run at all, so I'm not following how batteries would be a factor one way or the other.

Brian
It's not the batteries.
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
Les, please explain. How do the batteries come into play? Assuming a diesel with a mechanical lift pump. Doesn't need any electrical to run at all, so I'm not following how batteries would be a factor one way or the other.

Brian
Load on the alternator to recharge them. At 90A it’s typically 2hp loss. If batteries are way down you’ll be in bulk with a full field from the regulator, and full load from alternator
 
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