Onan generator BGE.......Spark Plug replacement difficulty

[bigbob70]

I'm trying to replace both spark plugs on my Onan generator BGE model 8663....

I can't seem to get to the rear plug....HELP...

Thanks in advance


edit by staff - changed message icon to topic solved

 

[darsben]

Sometimes you have to remove the unit to get to the rear plug.

 

[Gary RV_Wizard]

Plug access (or not) is largely a matter of how the Onan is installed in a particular coach body, but rarely is it easy on the BGE. Rumor has it that many don't ever get the rear plug changed.

 

[KandT]

Plug access (or not) is largely a matter of how the Onan is installed in a particular coach body, but rarely is it easy on the BGE. Rumor has it that many don't ever get the rear plug changed.

To Gary's point, there comes a time in nearly every project I do myself where I ask myself "Am I about to do more harm than good here?"  It took 45 years but now sometimes I leave working equipment alone.

 

[bigbob70]

Thanks for the replies....My generator looks like with the removal of a few bolts and the disconnecting of some electrical leads, fuel line etc that it should drop straight down with the assistance of a floor jack...Mine doesn't appear to be the type of generator that slides out but rather drops down...

If I can get it 6-8" lower I should be able to get to that rear plug....I'm sort of conflicted as to whether it's worth the trouble or should I do it for the experience in case the starter or coil goes haywire....

Whoever designed that rear plug must have had a warped sense of humor....

 

[Roy M]

You ever tried to change them in a V-8 Monza or Maverick? ;D  Don't blame Onan, the coach builder is the villain here. At one time I serviced rv generators, the other techs were either scared of electricity or lacked the patience. Some of them were a real bear to access.

 

[NY_Dutch]

Take a good look at the mounting setup. On our previous motorhome, I was able to service the top and back side of the generator by putting a raised bottle jack on a few boards under the front edge. After removing the front support bolts and just loosening the rear bolts, I used the jack to swing the generator down enough for access without disconnecting anything. On our current motorhome, there's enough clearance at the top of our BGE that I can reach the rear plug, etc., without removing anything.

 

[bigbob70]

Thanks Dutch.....I was thinking of that very thing but wasn't sure it could be done that way until your post....Yeah, it looks like you can loosen the rear bolts then remove a couple of side bolts etc then lower the outer edge of the generator via floor or bottle jack just enough to gain access to the rear plug after disconnecting the front metal straps....

That's the way I'll go about it after the new plugs get here....

 

[NY_Dutch]

Great! Just check that there's enough slack in the wiring and fuel line to allow for the tilt. Mine was ok, but check yours to be sure there's no surprises.

 

[John Hilley]

Is it running smoothly? How many hours on it? Maybe it doesn't need to be changed.

 

[jubileee]

  I use to run 25+ small gas engines on pumps on my semi tankers. I had only two things ever go wrong with spark plugs. Electrode burn off and carbon buildup. Electrode burn off to an unacceptable gap took about 2500-3000 hours. Carbon buildup varied engine to engine. We usually did a carbon clean up if engine was running rough to clean valves and plugs. This consisted of misting water into carb intake while engine is running wide open for a few minutes.

 

[bigbob70]

Thanks for the input....Probably the smart thing to do is ignore the rear plug... I'd almost take a bet that it is fine but I want to get to it anyway...It'd bug me if I let it go not knowing for sure it's condition...I'm assuming if the consensus is to let it go then the previous owner or owners may have done just that which makes me want to find out if that plug has ever been changed...

Wish me luck...

 

[NY_Dutch]

I changed the plugs in my BGE at about 1600 hours just for my own peace of mind, Bob. At $2 a piece, it seemed like cheap insurance.

 

[bigbob70]

Dutch....That's exactly the reason I decided to tackle that rear plug and thanks to a previous post of yours as one who actually did the job I now feel encouraged to do the same...

I may regret saying this but it doesn't look that difficult....I'll post how the job went when I get it all done...

 

[John Canfield]

Please take some pictures - you might be able to help others down the road with the same situation.

 

[bigbob70]

Sorry, I didn't take pictures ....All one has to do is loosen the 4 bolts about half way on the backside of the generator then remove the two bolts on the right side....After that I placed the floor jack in position and took the weight off the two front metal support straps then removed the straps...

Once all that was done I lowered the floor jack and the generator tilted down on the one side which gave me enough room to get to the rear plug....I still had to feel my way to the plug but at least I had the room necessary to do that...

Just as I suspected that rear plug was never changed as evidenced by green engine paint still on that plug...

Once the plug was replaced I raised the floor jack but I was a bit off center so the bolts on the right side didn't line up...With the help of a bottle jack I got everything into position and tightened it all up....

Thanks to Dutch's post as one who actually did that job before...... I then knew how to go about replacing that rear plug...

It's not that difficult as proven by the fact that I did it...One note...Before you lower the generator make sure you have slack in the electrical and fuel line ...In my case all I had to do was remove a clamp which gave me the needed slack

 

[ChasA]

Congratulations Bob.

 

[Gizmo100]

Nice work...And thanks for sharing.

 

[NY_Dutch]

Glad to see it worked out so well for you, Bob!