Universal m-18 won’t start sometimes

[sailing11]

Hello,
I have a Catalina 27 with a universal m-18 diesel motor in it. I replaced the glow plug switch about 6 months ago as the previous one was pretty sticky and wouldn’t disengage anymore

Now I have a separate hut possibly related problem: Today I ran the motor for 90 mins while cruising and got to the dock and shut it off for 10 mins. I tried to start it up again and nothing happened. No motor turning over or grumbling - no anything. I waited a minute and tried again and it started right up no problem. This has happened to be a few times now. I’m wondering if my starter switch could need a replacement?

After only sitting for 10 mins after being ran for so long, the glow plugs should not need to be used so I don’t think it’s a glow plug problem but I’m not sure.

Any thoughts?


Thanks,
Pete

 

[jviss]

Do you have a wiring diagram? My Westerbeke standard wiring is such that the starter circuit isn't energized unless the glow plug button is depressed, even if glow isn't necessary.

Other than that, probably your starter switch.

Do you have electrical troubleshooting skills, and a volt meter?

 

[sailing11]

Yeah I have a multimeter. Also I had the glow plug switch engaged when I tried to start it and it did it go. I’m pretty sure it’s not the glow plug switch l. I guess maybe there’s a poor connection. I have the wiring diagram as well

 

[jviss]

I assume you have a car-style keyswitch, like OFF-ON-START. Is that so?

Is anything energized when the switch is "ON," like gauges, gauge lights, etc.?

 

[sailing11]

I have a key switch that I turn over. This makes a buzzing sound so it is def minutely working. Then I hold the glownplug switch in and once that is warm, I pull the starter switch out which starts the motor

 

[Stu Jackson]

I guess maybe there’s a poor connection.

You're right, that's what it is. Check the ground lug on the bell housing first, that's usually the culprit. Good luck.

 

[jviss]

You're right, that's what it is. Check the ground lug on the bell housing first, that's usually the culprit. Good luck.

Well, I'm glad that's settled! Thanks, Stu, for sorting this out. Nothing more to see here.

 

[Stu Jackson]

Pete, some of the info here could be of assistance to you, too.

Critical Upgrades http://c34.org/bbs/index.php/topic,5078.0.html

 

[jviss]

Maybe I'm missing something, but I looked at that page, and I can't find anything about this particular problem, or the M18, or the Catalina 27. Maybe you can point it out?

I must confess, that I enjoy this forum, and I think it's poor form when someone asks a question, or for help debugging something, to immediately direct them to a link off-site. I can see when it's a question of where someone might find information - like, "what's a good source of C34 info?" But to just squelch discussion here with a response that says "go to this other site" is rude.

 

[LeslieTroyer]

@jviss what your missing is the commonality many of the universals have in common. The M18 starting circuit is the same as the M25 on the 30,34&36. And is actually the same starter and engine panel. Wiring and parts did change thru the years but is consistent winthin a fixed time frame.

From the details above it sounds like some parts have been swapped out, pull to engage the starter is a new one for me. Some years the glow plugs had to be on to power the starting circuit, many owners changed this. I think they did this so the lift pump was running.

 

[jviss]

pull to engage the starter is a new one for me

Yea, me too. So much for all that commonality they have in common.

On my C36 the lift pump ran with power on at the keyswitch. No glow plugs necessary to crank. I've only ever seen the started circuit energized by the glow circuit on Westerbekes.

I was going to suggest a step-by-step troubleshooting process for the OP. At the end of the day, it seems the starter solenoid is not being energized, or it's just no good.

 

[sailing11]

Thanks for your help. I took off the the ground on the bell housing and took a wire brush to it, although slightly corroded it looked fine. I wiggled all of the wires that I could and nothing looked out of ordinary. Also took a wire brush to the battery terminal wires. Assembled back together and it started no problem. Fingers crossed it keeps starting but if it doesn’t then I guess I’ll have to dig deeper and look at changing some of the wiring based on the website Stu referred to

 

[jviss]

Stu was probably right about the ground. I hate that ground arrangement, but it seems all Universals are done that way. Mine (M25) was almost right under the heat exchanger, and always ended up getting some salt water on it.

I recommend assembly of the ground with some dielectric grease, and then once tightened well, paint it! Seriously, everything on a marine engine should be painted.

 

[LeslieTroyer]

I had occasional start problems cleaned up everything, even replaced the starter while sailing, for no help. - turned out to be a bad battery cable, between the switch and starter.

In investigating the start circuit I discovered that the starter solenoid pulls 32A while engaging the bendix then 10A to hold it out there. That’s a lot of current running up to the engine panel and back to the starter, also a lot of amps for the small push on connector. Luckily it’s for a short duration. I added a 60/40 relay before the solenoid and it seems to improve starting operation. Note: this is a common fix for Yanmar engines.

 

[jviss]

Wow! I had no idea the solenoid coil would require so much current. Might want to install a solenoid solenoid! Is that what you meant by 60/40 relay?

 

[LeslieTroyer]

60/40 represents the amp capacity of the relay normally open and normally closed contacts.

Edit: the solenoid is more than providing power to the starter, it also pushes the starter gear onto the flywheel then provides power to the starter. Most car starter rely on the spinning action of the gear to move it into position.

 

[odaydokay]

Do you hear the fuel pump running? Simple, I know but worth checking. Happened to me; bad pump ground wire connection.

 

[sailing11]

Will the fuel pump be activated when I turn the key over or is it only activated when u pull the start switch?

 

[sailing11]

I had occasional start problems cleaned up everything, even replaced the starter while sailing, for no help. - turned out to be a bad battery cable, between the switch and starter.

In investigating the start circuit I discovered that the starter solenoid pulls 32A while engaging the bendix then 10A to hold it out there. That’s a lot of current running up to the engine panel and back to the starter, also a lot of amps for the small push on connector. Luckily it’s for a short duration. I added a 60/40 relay before the solenoid and it seems to improve starting operation. Note: this is a common fix for Yanmar engines.

Well it didn’t start again. But then did when I waited a minute or two and tried again. When it doesn’t start, I am getting a “clicking” noise when I pull the start switch but that’s it. Seems like it could be a lot of things. So far the connections on the battery look ok, as do the connections to the solenoid and the ground. I wiggled all the wires I could find all all seem to have a good connection. Any idea how to tell if it’s a bad wire ?

 

[sailing11]

Yea, me too. So much for all that commonality they have in common.

On my C36 the lift pump ran with power on at the keyswitch. No glow plugs necessary to crank. I've only ever seen the started circuit energized by the glow circuit on Westerbekes.

I was going to suggest a step-by-step troubleshooting process for the OP. At the end of the day, it seems the starter solenoid is not being energized, or it's just no good.

It happened again. Any ideas on how to troubleshoot this ?