Onan Generators

[Trojan]

I did not find a number to call for a manual for my generator on the Onan web sight. I was down to the boat and ckecked out the glowplug today. The glowplug measured 1.2 ohms. From the panel on the genset to the glowplug the voltage red 11.99 volts. From the remote switch to the glowplug the voltage read zero. I checked the switch, it was bad. I guess that explains the hard starting.
Now if I can only get a manual I will be all set. I hope.


BILL

[Nonchalant1]

Try Cummins-N-Power (Onan's new owner) at their HQ in Minnesota at (763) 574-5000. If they don't have it, I can get you the Onan service dept where I ordered my old manuals here in Illinois.

[Beckytek]

Here is the number I call for parts from Onan,
Central Parts Warehouse
1549 Bobali Dr
Harrisburg, Pa. 17104
717-986-9062

[Trojan]

Thanks Guys. I will give them a call.

BILL

[Will]

Bill,

I expect to pull the old Onan 7.5 kw out of the boat over the next 2-3 weeks. Do you still want the manuals? If so, I'll send them to you as soon as it's out of the boat.

Will

[Trojan]

I Sure do Will. I also got your e-mail pictures, Looks good. I went to the boat Tuesday. Must of had a senior moment I forgot the camera.


BILL

[Will]

Bill

Ok, I'll send them to you.

I responded to the e-mail address indicated on an earlier Generator thread of yours but sent no photos. Since I never got an email reply, I'm wondering if I have your correct email address.

Will

[Trojan]

WillI have been using my laptop and I can recieve email I just can't send it yet. If I get on my old computer I can send email OK. Your pictures of your radar tower came through just fine.



Bill.

[Trojan]

I found out what was wrong. The wire that feeds the 12v to the glowplug relay was eaten in half. I cut and spliced it. It works fine now. Tomorrow I will change out the complete wire. It had been spliced in 4 places. Not good. I also said I only have one glowplug but I was wrong. It has 2 plugs and a air heater. I just could not see them without standing on my head. Someone in a real early thread said it only had one so I did not look for the second one. I also found out that the generator can be rewired for 220 volts AC. Cool. The things you learn when you start digging.



Bill

[spartonboat1]

Very interesting thread!!! At least to a limited number of us with MDJE's.

I have the exact model above, the MDJE 7.5Kw, 2268B as a 1972 model. Bench rebuilt and runs great. Too noisy for most I suspect, but an the sound is an acquired taste. I was the one (culprit?) I suspect who indicated that only one cylinder was helped and to expect lots of smoke, until the unaided cyl heated up. So a major mea culpa on that info on my part. I could have sworn that a very experienced Onan tech told me that only one cyl was aided. I double checked my typed notes based on my phone conversation with him, and the notes clearly indicate that only one cyl (#1) is aided. Very curious.

My curiosity is now very high to locate both the glow plugs and check if they both function. The Operators Manual and Parts Catalog schematics/diagrams only indicate a single plug, and then not at the installed location, but only as a separate reference.

However I did find a schematic #612-4792 that clearly calls out a BOM with 2 glow plugs (2 cyl) or 4 glow plugs (4 cyl), called out as HR's #1-5. The circuit diagram that the Manifold Heater Solenoid provides 12v+ (B+) to HR1 (Manifold Heater), and HR2 (glow plug 1) and HR3 (glow plug 2).

Frankly, until this post, I was not aware that glow plugs were installed, but I did know that the manifold heater was present. I had a hard starting issue, but the tech said that one/half of the heater plate in the manifold was open/burned out, and that installing a new heater plate (I call it the toaster oven) cured my started situation.

However, the hard starting was still somewhat intermittent, until I had some bad fuel get into the fuel filters. After all the genny fuel filters were changed out, the starting became very consistent. I rarely fails to start even down into the low 30's. But The manual is clear that lifting the pre-heat switch for one minute is required.

Manuals I have for this unit are:
>Operators Manual and Parts Catalog- MDJE Series, book #968-325,
>Technical Bulletin #T-021, Installation of Onan Marine Electric Generating Sets, Aug 1971,
>Control-Gen Set (Wiring Diagram) Schematic/Bill of Material #612-4792, update note 12-20-77
>Onan Parts and Service Centers March 1972 #F-115

I have a digital camera and could shoot some pages, or I also have an HP Scanner and could scan in some (all) of the catalogs pages.

To quote Queen, I've got egg on my face, such a disgrace...