Jinma Key Switch replacement From NAPA?

[greg_g]

Interesting choice. Unless I missed the fact that your tractor has a cab - and given the all the time my tractors spent in the rain - I think I'd have chosen the marine grade switch.

//greg//

 

[TruChaos]

Interesting choice. Unless I missed the fact that your tractor has a cab - and given the all the time my tractors spent in the rain - I think I'd have chosen the marine grade switch. //greg//

I considered it but when I priced the marine switch is was a bit more expensive and I never work in the rain and the tractor is parked in a garage. So, water isn't an issue.

I'm convinced that if the Jinma switch works, anything will. : )

 

[greg_g]

I'm convinced that if the Jinma switch works, anything will.

Well that's the whole point. Jinma switches usually work fine - until they get wet.

//greg//

 

[TruChaos]

UPDATE

I really like the new Cole Hersee switch and I highly recommend it. It's also a very easy installation as it fits the existing key plate after the flat is rounded out with a rat tail file.

Pro:

1) Much higher quality than the factory Jinma and Wesco Ford switch

2) Start without glow plugs

3) Start with glow plugs but not during cranking

4) Start with glow plugs while cranking

5) Real key, not a generic one key fits all key cylinder

6) Only minor fitting required (remove key plate flat)

7) Switch has screw terminals like the factory switch so no need to cut the factory terminals from the wire harness.


I've been a manager of a series of electrical engineering labs for over 20 years and I've spent a lot of time observing how electrical devices/components fail. There is no reason to believe the Cole Hersee switch will have a problem with water as long as it's not exposed to salt water. It's designed for a fresh water marine environment. The switch is designed with drain holes so it cannot hold water if water should find it's way into the housing. It's the trapped water which causes the real problems with energized contact erosion.

Con:

Price is slightly higher than the Ford switch but is still an excellent value

 

[Swampy]

I replaced my Jinma switch with a Cole Hersee M924. It was a lot easier than I thought it would be. I looked at the Hersee specs and saw the switch is a lower current unit but allows glow plug heating while starting (unlike the Jinma factory unit) so I installed a 40 amp relay. The Hersee switch is far better quality than the Jinma and the Wesco Ford switch. I initially bought a Ford switch but realized it wasn't much of an improvement over the original.

This conversion only requires one connector to be cut off the existing wiring. Since both the Jinma and Hersee switches use screw terminals very little change required.

Here's a circuit diagram of the conversion.

Do I need two(2) relay switches, on your diagram you show two wires connecting to a relay switch(es). One ammeter to glow plugs and I'm not sure what. I bought the Hersee M924 but now do I need one or two relay switches and what actual wires will be connected? Thanks for your input.
Swampy

 

[greg_g]

Actually, you may not need any. Depends upon whether or not your glow plug circuit is fused. Besides, I personally disagree with the configuration that particular wiring diagram presents.

Early Jinmas did not have a pre-heat fuse, hence some owner decisions to add an aftermarket relay or breaker. Determine if you have a glow plug fuse first, then we'll go from there. Old Jinmas had one 30A system fuse, newer ones had that plus a 30A pre-heat fuse.

//greg//

 

[Swampy]

Greg,
Thank you for the reply. Yes I have a fuse for the glow plugs I believe. Top down in fuse "box" is:
30A Ammeter
10A Regulator
20A Front Lamp
20A Rear Working Light
7.5A Flasher
10A Horn
30A Preheat

I am thinking the Preheat is for the glow plugs. Is this correct?
Looking forward to more information if you don't mind.
Thanks again,
Swampy

 

[greg_g]

Correct. The Cole-Hersee website no longer lists the M924 as a current product. So before "more information" could be forthcoming, I'd have to know more about which switch you're going to use to replace the Jinma original. Once the post positions on the rear of the switch are determined, then we can talk about which wires go where.

What you'll be shopping for is a 4 position switch. Look for one that's water-resistant, but - unless your tractor never sees a roof - the expensive marine grade switches are overkill. But you're eventually going to get caught in the rain, so a water resistant switch is a plus. It must be a 4 position switch (off/on-acc/preheat/start) because of the glow plugs. It should also have no less than 4 post/connectors on the back. If it's got more, no biggy - they just go unused.

A glow plug relay is a benefit, but not a must. If you don't have a hard starting diesel, let's not go there. If you do, I can add it to the discussion.

//greg//

 

[Swampy]

I have purchased already from elecDirect.com a Cole Hersee Co. M-924 switch. On the invoice the description states: 3-position:OFF-RUN(Push to Choke)-Battery/Start 6 Brass screws

As I look at the back of the switch the screws on the back appear to be labeled as follows:
BAT
MAG
MAG
CH
IGN
ST

Hope this information is helpful.
Again thanks,
Swampy

 

[greg_g]

Nope, it's actually a 4 position. The "push" function counts as #4. But are you positive it's a M924? The M stands for "marine", but the markings on the back are aeronautical (airplane switch):
M = Magneto (both times) you probably won't use these
ST = starter solenoid (via the clutch interlock switch)
BAT = 12v from the ammeter
CH = Choke - but it will do just fine connected to the glow plug wire
IGN = ignition. Basically just the ON-ACC position to power things like the instrument panel and battery charging when the engine is running.

//greg//