Engine won't start

[KennyBene]

I would appreciate some advice- my Universal MX 25XP won't start (1990 C30). Turns over but does not seem to have adequate compression to start. All filters new and clean and fuel is getting to the injectors.
With the air filter removed, on cranking smoke, fumes and vaorpized fuel is coming out of the intake.
Mechanic suspects valve issues or worse but people are telling me the exhaust elbow might be the problem.
The engine did start and run normally 3x this season with normal discharge from the stern outlet but the engine does not develop much power (owned for 3 seasons and power has never felt like it should).
Any thoughts on what the problem might be?

Thanks in advance for any insights.

 

[Don S/V ILLusion]

If you ascribe to the theory that it is smart to start with the easy (read - cheap) stuff first, check the exhaust elbow and have the injectors checked.

 

[Brad Woodward]

I had that problem when I first got my boat. Turned out it would start after 30 min of cranking. Had to keep the water lift muffler drain valve open to keep water from getting into the exhaust ports. My glow plug switch was bad. Put in a new one and it started wright away. Later when I had another problem and it would start but had low power it was a very small leak on one of the fuel injector tubes fitting was loose and had a slight diesel leak. So it could be injectors if it was running rough or low power but could be the glow plugs may not be getting hot if it isn't starting. A simple volt meter can check for voltage at the switch first, if you have that check the plugs if they are hot start looking at an injector problem. Pump and or injectors.

 

[centerline]

With the air filter removed, on cranking smoke, fumes and vaorpized fuel is coming out of the intake..

this does kinda indicate valve train or timing issues. but more likely a blown head gasket...
it could very easily be a bad valve or valve seat. if you lost a tip from a nozzle, it is very easy for it to damage a valve as it passes or attempts to pass out of the cylinder.

1 bad injector or cylinder wont usually keep an engine from running, but a head gasket blown between two cylinders could.... and it would also explain the blow back out of the intake...

 

[Anonymous 121765]

I like what Don suggested. I do know that some exhaust ells by design can & will clog.
Centerline had a good thought on problems. I really liked his take on a blown head gasket.
If a blown gasket, check your oil for a milky residue on your dip tube. If diesel oil black, that's not the culprit.

Your post of intake blowback suggests to me your exhaust ell may be clogged not letting exhaust exit.

Another item to always remember, is to NEVER crank your engine beyond six seconds at a time when starting/cranking your motor. This can & will cause an opposite exhaust suction condition back to your motor, if your discharge is below the water line or your muffler box is full with exhaust water.

CR

 

[Stu Jackson]

It is rare for exhaust "elbows" to get clogged on Universals, simply because they are completely unlike the exhaust "elbows" many skippers on this forum with Yanmars are used to. The "elbow" on Universal engines consists of a simple injection nipple on the hot gas exhaust riser, a 1 1/2" pipe from the back of the engine to the waterlift muffler.

To check it, simply take off the water injection hose and look inside. In 16 years with our boat and reading these forums and helping to build our C34 engine information, I have not heard of ONE connection being plugged. Never. What happens is that the exhaust riser corrodes from the mixture of the hot gas and the hot water. That's why Catalina and Catalina Direct sell replacements and why many skippers build their own risers.

http://www.c34.org/wiki/index.php?title=Adjusting_Valves

You might have other issues, since we're not there and dependent on your report, that is what we can offer.

 

[Anonymous 121765]

Stu,

DUH, Good call.

What I was referring to was the highpoint 180° anti siphon fitting (not mixing ell).
My friend's boat has a 25XP with a mixing ell. These are normally not a problem. However, on his muffler box exhaust hose to a high point, the PO installed a Yanmar fitting. They are notorious to clogging simply by their baffle design. This was what I was referring to. A mixing ell would not backpressure thru the air intake.

I guess my typing was going faster than my brain was thinking. Spank me when I'm bad pal.

CR

 

[KennyBene]

Thank you all for the valuable (and valued) input.

Since yesterday's post I went back to the boat and pulled off the valve cover. While everything seemed to be working properly when cranking- everything under the cover was rusted and looked dry- as if little or no oil is reaching these parts. The head comes off tomorrow and maybe we'll find the problem but it's looking more and more like there are lower engine issues and I should start thinking about repowering with a rebuilt 25. $cary thought...

I am on Long Island (Northport) and would be interested if asnyone has good/bad stories to share regarding repowering this boat.

 

[jrowan]

Just curious if you had your mechanic check to make sure that your glow plugs are working & getting power. My Universal starts immediately when the key is turned (knock on wood) but it will not start at all, if it does not get at least 30 full seconds of glow plug pre-heating before turning the engine over. Good luck & let us know what the culprit is.

 

[Stu Jackson]

Excessive glow plug time? Check the wiring, sounds wrong. Then do this:

http://www.c34.org/wiki/index.php?title=Faster,_More_Efficient_Glow_Plug_Heating_with_a_Solenoid