Universal M25xp won’t start

[Zingman]

Greetings!
Gremlins have been residing in my electrical system for a while now and I thought I was well on my way to purge them but THEY’RE BAAAACCK! I have a 1987 Catalina 34 with the 23hp M25XP diesel. This past summer it began to have an intermittent start issue. Mechanic hires to replace starter button, wiring, solenoid & fuse. Still had intermittent trouble starting. Next swapped out starter. That improved things dramatically. Then starting became difficult again. Determined that one of 4 batteries was bad. Replaced battery, started fine. Couple days later the engine wouldn’t start and needed a jump. Alternator tested fine, good voltage to solenoid & starter. In the end I determined the original onboard Promariner charger had failed and the combo of inadequate run time or undersized alternator resulted in deAd or dying batteries.

So I have been working to upgrade the charging system and while at the dock have been maintaining the 2 banks of deep cycle batteries (1 set GRp 27, 1 set GRP 24) with a plug in 12v charger. Weekly visits to run engine and all seemed fine. Planning the upgrades along the way. I even took the boat out yesterday and dropped a few crab pots!

Upon return today to go retrieve dinner the engine would not start!! I had the switch to ALL, turned the key, heard the buzzer, held the glow plug for 15 secs, upon depressing (no pun) the starter button the buzzer quit but the engine won’t turn over. Now when the key is turned the buzzer does not sound but the fuel pump does run. Batteries show full charge.

Strange behavior is the needle on the fuel gauge pegs to the right and vibrates along with the fuel pump!

Any thoughts will be greatly appreciated!!

Bill Z

[DeepFrz]

What is the battery voltage when you press the start button?

[jimbunyard]

Sounds like multiple ground problems to me.


Without seeing and knowing the condition of the system overall, a good place to start is with cleaning and tightening all connections associated with the problem circuitry.


Check all battery cables for the same relative 'suppleness'. If one (or more) cable is noticeably stiffer than the others, it could be internally corroded and need replacing. They can sometimes pass 12 volts but fail to pass enough amps to do the job...

[Lepke]

In trouble shooting starting issues, I have run into problems where owners used standard auto battery cables. Corrosion can creep up the cable and before it fails completely, the high demand of starting will often burn thru the corrosion but the lower amps of charging will not get thru. Leaving weak batteries. Cutting thru the cables, I found green corrosion all the length of the cables.
As jimbunyard said: a good start is cleaning all contact points and connections including the grounds. When it fails to start, try jumping the starter solenoid. If you have jumper cables, try going direct from the battery to the starter.
Check the voltage at the starter when cranking.

[Wotname]

Welcome aboard CF, Zingman.

[Tetepare]

The starter key has to be all the way over to warm the plugs. If dirt gets in the switch it will still buzz but not get the the point of warming plugs. You can hear a slight difference in buzzer pitch when all the way over.



If your muffler is flooded the engine won’t start. Drain the muffler.

[wyb2]

Originally Posted by Zingman

... Now when the key is turned the buzzer does not sound but the fuel pump does run...

Just a data point - on our '85 C36, someone put a 24v buzzer on our 12v panel. No idea why. The result it that sometimes it buzzes when the key is on (and engine is stopped), and sometimes it doesn't. No rhyme or reason, not an indicator of battery voltage or likelihood to start or anything, just purely random.

[Stu Jackson]

Zingman, you are very welcome to join us at our Catalina 34 website, in addition to this fine forum here.

Here's just one of many up your alley:

CRITICAL UPGRADES - DO THESE OR ELSE!!!

Look around in the rest of the Critical Upgrades and also the "101 Topics."

Like this one:

Engines 101 - The BIGGEST & BEST collection of M25 Series Universal Engine Information on the Internet, plus some M35, too

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

Good luck.

[mogulskibum]

My 25xp had starting issues until I:
1. Replaced the glow plugs; replacements are less $5 each if you buy them from a kubota dealer.
2. Wired a larger wire to connect the glow plugs - this involved putting in a relay rather than running that much current through a long run to a small switch and back again.
3. Let the glow plugs heat for at least 30 seconds if you're starting a cold engine. Even longer if the weather is cold.

[Stu Jackson]

Originally Posted by mogulskibum

My 25xp had starting issues until I:
1. Replaced the glow plugs; replacements are less $5 each if you buy them from a kubota dealer.
2. Wired a larger wire to connect the glow plugs - this involved putting in a relay rather than running that much current through a long run to a small switch and back again.
3. Let the glow plugs heat for at least 30 seconds if you're starting a cold engine. Even longer if the weather is cold.

Good idea.

Zingman, it's right there in the C34 tech wiki:

Glow Plug Solenoid or Relay Installation for faster starting

[Boatyarddog]

Originally Posted by mogulskibum

My 25xp had starting issues until I:
1. Replaced the glow plugs; replacements are less $5 each if you buy them from a kubota dealer.
2. Wired a larger wire to connect the glow plugs - this involved putting in a relay rather than running that much current through a long run to a small switch and back again.
3. Let the glow plugs heat for at least 30 seconds if you're starting a cold engine. Even longer if the weather is cold.

Older Catalinas are notorious for undersized battery cables, and excessively long runs to the starter.
Remember that battery grounds go bad as well.
Moving the battery switch closer to the starter helps, this may involve moving battery's as well, as they are usually mounted under the nav. table.
High current loads can be run using relays, so you don't have to use big guage wires to power the glow plugs as mentioned above.
Connections and condition of cables is most important.

[boeing1]

if you have a disconnect plug from engine to start panel possible corrosion in plug, known problem with disconnect plugs, if no plug on your installation check both start and glow plug switch if you need to depress both switches to start possible one of them is inter-mite,

[mogulskibum]

Originally Posted by Boatyarddog

Older Catalinas are notorious for undersized battery cables, and excessively long runs to the starter.
Remember that battery grounds go bad as well.
Moving the battery switch closer to the starter helps, this may involve moving battery's as well, as they are usually mounted under the nav. table.
High current loads can be run using relays, so you don't have to use big guage wires to power the glow plugs as mentioned above.
Connections and condition of cables is most important.

It's not just Catalina, I have yet to buy any boat where I thought the battery cables were adequately sized for their length. I'm sure there are some manufacturers who do a good job, but it's definitely not unusual...

[Mike Banks]

I think your alternator is not getting excited initially--so it is not charging the battery. I suspect the voltage regulator is faulty or is short-scircuited if the red warning light is not appearing.

[RSB333]

Please clarify - does the engine turn over but fail to catch, or do you get no cranking from the starter. I have a similar situation, (no crank when batteries are fully charged) and have been checking all the connections, replaced the starter and solenoid, key switch, etc. Still having intermittent problem.
RSB