$3150 to service Onan 7k and replace ignition coils!

So the good news is I have a better understanding of this thing for next time I have to pull it out again.

This was one of the biggest silver linings to my generator work. I now know the thing very well. I can yank my genny in under 30 minutes now.

Steve

Caterpillar wanted 3,000.00 and change to change coolant, change hoses and belts and thermostats.
There is ll kinds of room around our engine to boot. Twenty years ago even ten years ago, maybe I could d it myself. One factor may be that they know many/most RVers are not able to o this fairly simple work themselves so they charge what they can get.
But...These places work on the big trucks and the charges are covered by companies that charge off the work as expense. Technicians do not get but a fraction of the 150.00 to 200.00 an hour or whatever the rate is.
The companies have a lot of business expense to cover, of course it is charged off on taxes. I have no idea or where the middle ground on all this is but for Individuals these kind of charges are hard for many of us to bear.
In Tucson at the Cat shop we had batteries and dipstick replaced. I don't remember how much but it was reasonable. Biggest cost was they had to get the batteries from a Golf Cart shop. Quoted one price but charged them/us a lot more when they found out it was for an RV. I can't remember their name but would recommend them. Pulling that generator appears to be a bear of a job.
I am going to change the coolant to prevent any of those problems if I find a shop around here that has a reasonable rate. No thought by Freightliner to make dropping the generator easy. Still there may be a couple o tricks to simplify the job. We use to have some Techs from Freightliner, Cat and Cummins here.
Have not seen any posts by them in ages.

Double post - sorry

bounder39zman wrote:
OK..fault code 47 is an ignition fault code. the control board is not "seeing" one or the other ignition coils. could be as simple as a unplugged wire, or a bad coil. I have had shop towels or paper towels get sucked up into the air intake, and dislodge wire off coil. So looks like you probably have bad coil, disconnected wire to coil, or possibly bad control board.. And , from experience, dont lay shop towels or paper towels near air intake....

So the good news is I have a better understanding of this thing for next time I have to pull it out again. The bad news is I'm going to have to pull it out again...

Got it out last night, then this morning replaced the coils, set the magneto gap, checked the spark plugs & belt and then put everything back in.

Started up fine. Ran smooth for 40 minutes, shut down. Would not start up. Waited about 15 minutes, started but not easily - took a few seconds as could tell it was trying to "catch." Then shut down with the same code 47.

I understand I should change the control board next - do you have an idea why this would be the problem?

OK..fault code 47 is an ignition fault code. the control board is not "seeing" one or the other ignition coils. could be as simple as a unplugged wire, or a bad coil. I have had shop towels or paper towels get sucked up into the air intake, and dislodge wire off coil. So looks like you probably have bad coil, disconnected wire to coil, or possibly bad control board.. And , from experience, dont lay shop towels or paper towels near air intake....

Part you called fan shroud, I referred to as flywheel cover. either term ok. Might give Careco Gen Serv, in Fort Mill, SC, only 1-1/2 to 2 hrs from you a call. I need to look up code 47, don't remember specifics of that code,

Not too far from you, a couple hours drive, is Appalachee RV Center in Auburn, GA. I have used them for lots of stuff, and while not cheap, it will be fixed right the first time. They repaired my generator that needed slip rings and something else I don't remember right now. It works better now than it ever did. Call them 770-868-0999.

bounder39zman wrote:
couple of things: the 4BGE Maillemaker refers to is a great generator, I have owned several, and still have one mounted on a cart for a "portable" genset. But it has nothing in common with your RVQG (7HGJAB I assume). Your set has 2 magneto/coils, one for each cylinder,a triggered by magnets on flywheel.
to access them you have to remove genset from coach, lift engine-gen assembly off of base tray, turn on back to expose bottom of set. Then remove flywheel-belt cover to access magneto/coils. There is no ignition module, per se... the magnetos are controlled by main control module. $50 is ok price for coils, the main control board is $400+, depending on spec of genset. The hydraulic lift table is a very useful item, and you need some lifting equipment or couple strong friends to pick up the engine/gen assembly up from the base tray.
I would like to know the fault code the gen is giving you when it shuts off.
I have surveyed a number of Cummins/Onan dealers in SE US, they typically have labor rate of $150-160 hr
R&R of set from Tiffin should require 2-3 hrs at most, replacing coils, and drive belt while "in there" and bench test run about 3-4 hrs in a well equipped shop that has experience working on these sets

Wow I wish I could have found a shop to only charge me that many hours for labor. Thanks for that tip of needing to lift the engine / gen assembly; looking at the service manual it's not immediately apparent.

I looked like I could tip the unit on it's back and remove the fan shroud to get access to the coils.

The code it gives me is 47, consistently. It's the only one I get.

I picked up an HF hydraulic table and plan to take the genset out this afternoon...

couple of things: the 4BGE Maillemaker refers to is a great generator, I have owned several, and still have one mounted on a cart for a "portable" genset. But it has nothing in common with your RVQG (7HGJAB I assume). Your set has 2 magneto/coils, one for each cylinder,a triggered by magnets on flywheel.
to access them you have to remove genset from coach, lift engine-gen assembly off of base tray, turn on back to expose bottom of set. Then remove flywheel-belt cover to access magneto/coils. There is no ignition module, per se... the magnetos are controlled by main control module. $50 is ok price for coils, the main control board is $400+, depending on spec of genset. The hydraulic lift table is a very useful item, and you need some lifting equipment or couple strong friends to pick up the engine/gen assembly up from the base tray.
I would like to know the fault code the gen is giving you when it shuts off.
I have surveyed a number of Cummins/Onan dealers in SE US, they typically have labor rate of $150-160 hr
R&R of set from Tiffin should require 2-3 hrs at most, replacing coils, and drive belt while "in there" and bench test run about 3-4 hrs in a well equipped shop that has experience working on these sets

That said, I purchased one of these 500 lb. Capacity Hydraulic Table Carts when I had to drop my gas tank to have it welded, and at the same time, replaced the fuel pump. This thing made the job quite safe as I didn't have any help with the process.

Thanks for that link, Rick! That thing looks PERFECT! I wish I had known about that before I got started. In fact I'm tempted to buy one even though I don't need it right now! :) that table jack would be just the thing for lowering the genny out of my RV.

Steve- you are awesome. Thank you so much for pointing me in that direction, and for your other advice as well.

I have a friend who knows a guy who has a shop with a forklift, and they're going to help me get this thing out. Conceptually I think I know what has to happen, and I'll get on over to the Smokstak forum and start asking more.

DW and I were talking about it last night and we could drop the $3k on this but in principle it just doesn't seem right for us. If it were $1500 I'd probably have said go but this is crazy.

No prob, Mark. Before I finally bit the bullet on figuring out my Onan the genny was kind of a magical "black box" to me that I was afraid to poke at. Now that I've done it, after spending 6 months dinking around trying to diagnose things I wish I had just bitten the bullet earlier and pulled the thing and found the replacement parts and just started replacing stuff. Like I said above - if you can find non-Onan replacement parts it gets really cheap to simply replace rather than trying to troubleshoot.

I don't know if the Onan 7K is like my Onan 4BGE but here is a word of caution: When you go to take out the ignition control module on the 4BGE, it will not come out unless you rotate the motor crankshaft until a short cooling fin comes up and lines up with the ICM. You have to look in there with a flashlight after you loosen up the ICM. Watch for the short fin to come up - only then is there enough room to pull the ICM out.

Are you sure you can't get to the coil without pulling the genset out? I replaced my coil several years ago for less than $100. The hardest part was removing the shroud and some of the other sht metal surrounds. Once removed the coil replacement was easy. It was a half day job including removal of the mouse nest under the shroud on top of the engine, it is a wonder that it did not catch on fire.

On my 4BGE, the coil is mounted on a bracket on the top-back side of the genny. It's possible, now that I know how it goes together, that I could do it without pulling the genny. Especially when I put down my RV jacks to lift the RV, and then put in jackstands under the frame (for safety) , and then tilt down the genny on it's swing-down tray (in my RV). I found it very hard to get the shroud bolts back in after removing because the shrouds flex (they are just sheet metal) and it was super hard to get the holes to light up with the threaded holes again. All this problem went away when I had the genny out and on my workbench.

Plus in my RV the genny is down low to the ground and so you have to work on your knees while trying to be hunched over reaching around the genny. It's a very uncomfortable position to work in.

Like I said, now that I know how to do it, I could probably replace everything again without pulling the genny. But, it's also so easy to pull the genny out that I might do it anyway just to make it easier to work on it. I can probably pull my genny in 20 minutes now. If I had that fancy jack cart that Rick mentioned above I could do it even faster.

But no, you don't have to pull the genny to replace many things on it.

Steve