Universal M25 - Weak cranking

[Buster007]

New to us boat. Catalina 30
Fresh battery.
Warm temps
After having Glow Plugs on for 15-20 seconds we hit the starter button. Appears like a weak battery barely turning her over. BUT, occasionally she will turn over like normal and start right up.
Run for 20 minutes and shut off.
Try to restart and weak battery symptoms again. Barely will turn over and wont start. But we know its not the battery.
Whats next? Ground wire? It does look rusty and crusty where its connected to the engine block.

[keepondancin]

Check and clean ALL connections

[Lepke]

Possible bad contact or ground, but probably in the starter solenoid. Because a starter draws high amps, most starter solenoids have a heavy copper disk that makes contact with the contacts to the starter and battery cable. Each time the starter is used, the disk turns a little. Because of the high amps, the contacts and disk get burnt and pitted a little. Eventually there will be areas on the disk that have deep burns and pits while other areas are less damaged. That's why sometimes the starter turns fast and other times it drags.
If you're ambitious, take the solenoid apart and file or sand the contacts and disk to make like new.

[Michael Cobbe]

One thing to check is a loose solenoid

[Buster007]

[QUOTE=Lepke;3223710]Possible bad contact or ground, but probably in the starter solenoid. Because a starter draws high amps, most starter solenoids have a heavy

Ok. I noticed that there seems to be a new solenoid recently installed.

[Buster007]

Here it is

[Maine Sail]

Originally Posted by Buster007

Here it is

That's not the starter solenoid, the starter solenoid is mounted to the starter motor. It is most likely a solenoid/relay for the glow plugs to avoid the high-amp glow plug draw from running through the teeny-tiny panel harness wires...

[Buster007]

Originally Posted by Maine Sail

That's not the starter solenoid, the starter solenoid is mounted to the starter motor. It is most likely a solenoid/relay for the glow plugs to avoid the high-amp glow plug draw from running through the teeny-tiny panel harness wires...

ahh ok thanks and I see the diagram now. today i will clean the engine ground and other connections, and if no luck go over the starter solenoid..

I have one 'starting' battery under the bunk and 2 house batteries under the nav desk. They both have a 1-2-all selector switches, however they both energize both the starter and house circuits! That doesnt make sense. Nor does the bilge pump wired directly to the starting battery.

[Tetepare]

There are two common problems with the C30 that could cause this, beyond batteries, etc.


First, the key switch to warm the glowplugs. It has a tendency to get dirty and not fully engage. When the key is "on" you should hear the buzzer, and when all the way over to warm the plugs you'll hear a drop in volume. Too often, it's dirty and won't get to the "warming" engagement; you have to listen for the drop in volume, not just a buzzer. The solution is to remove the key and spray WD40 or similar into the switch, then work it back and forth with the key to loosen things up.


The second is the POS instrument panel. POS is American vernacular for "not blue water." Electrical connections are poorly secured and can be intermittent or just fall off. Every year I have to pull the panel out and reconnect some wire or another.


So I'd start with the above first, as in my experience that's 95% of problems like this.

[wheelerwbrian]

Check the length of the run for the power and see if there is a voltage drop. Catalina 30s, some of them, were wired with the battery power going to the control panel and then back to the starter. The fix is to put a solenoid in the circuit, so that the control panel closes the solenoid and the starter is energized from a shorter run with larger cables.

There are diagrams online for this upgrade. I did it and it fixed the same problem.

[Scrimshaw4]

Depending on the age of the boat another problem with the earlier 30's is the wiring harness connection from the panel to the engine. On earlier models the connection was in the bilge just aft of the transmission and was very susceptible to corrosion. If that's the case, contact Catalina and they will put you in touch with the company that makes a replacement harness with a different connection location.

[wheelerwbrian]

Originally Posted by Scrimshaw4

Depending on the age of the boat another problem with the earlier 30's is the wiring harness connection from the panel to the engine. On earlier models the connection was in the bilge just aft of the transmission and was very susceptible to corrosion. If that's the case, contact Catalina and they will put you in touch with the company that makes a replacement harness with a different connection location.

concur on this - if the friction fit plug is still there, replace with a term strip.

[neflier]

I just went through this same problem on my C30 and it appears to be fixed. I cleaned the positive and negative battery leads and that did not fix the problem. As mentioned earlier, make sure the plastic engine harness plugs have been replaced with terminal strips. Mine was already converted. Also ensure the alternator output connects to the + battery lead on the starter by a short cable, and not routed back to the key switch and then back to the + battery lead. I needed to make this change. There were burn marks on the ring terminal insulation at the key switch. At the recommendation of the technical support at Catalina Direct, I also changed the key switch and start push button. After making these three changes (reroute alternator output, key and start switches), my slow cranking problem has not returned. I also purchased, but have not yet installed, a new starter. The tech support at Catalina Direct said they sell a lot of start and key switched, and not that many starters.

See the link below for more details on the changes needed for the engine harness:

https://catalina30.com/TechLib/Wirin...deInfoPkg1.pdf