Surging Onan 16

[thehorse 221]

Well the 416h has been helping move a lot of snow in little increments but nothing major. I have noticed that the engine definitely has an up and down cadence to it. It surges up and down. Nothing major but enough for me to make a post. I've checked to make sure the plug wires were on but not much else. It's just to cold to muck with in the non heated garage. Any suggestions? I could be imagining things but it may have a puff of smoke on the surge when warming up and choked, maybe 10 seconds worth. Any insight would be appreciated.

[varosd 1,185]

I think the most common issues is the Onan carbs  getting dirty..I would pull the top off the carb, check the float and remove needle valves and clean all ports.  I'm sure you run hi test/ethanol free gas.  my 416-H did the same thing about 2 months ago and after carb cleaning she runs great. only other thing could be governor.

[cheesegrader 433]

Onan surge is usually a fuel delivery problem.

A good carb cleaning works most of the time, but consider old fuel lines, weak fuel pump, and clogged fuel shut-off valve as well.

[Ed Kennell 35,735]

Since it's too cold to do the carb cleaning now, I would give her a good dose of Sea Foam for now and if the symptoms persist,  follow Dons advice when it  warms up.

I cleaned the carb on my 520  3 times  before the surging finally went away.

[thehorse 221]

Thanks,

I was thinking the exact same things. I'm out of seafood so ill pick up some tomorrow. I'll let you know how things progress.

Len

Stay warm all!

[Tankman 3,515]

My '90 520-8 used to surge. Doesn't since I started adding Berrymans to the fuel.

 

I use Berrymans, 1 oz per gallon and it does keep fuel line and carb clean. No more surging  

 

You can find Berrymans in most auto supply stores. Good stuff and inexpensive.

 

 

[Wheel Horse Collector 47]

I had one that surged I took the carb completely apart, blew it out, put It back together and I haven't had a problem since. So I would take the carb apart and give it a complete cleaning

[Theroundhousernr 589]

Thanks,

I was thinking the exact same things. I'm out of seafood so ill pick up some tomorrow. I'll let you know how things progress.

Len

Stay warm all!

All great suggestion. Just try to keep the seafood out of the onan. Especially shellfish, really tends to clog things up      Sorry, cracked me up this morning.

[Ed Kennell 35,735]

Enough Roundhouse.....clam up

[thehorse 221]

Again with the spell check.....Should have noticed something fishy. Not sure if its a FLUKE or what but usually leaves me crabby when it does this.

[jackhammer 544]

 

 

You guys are cracking me up

[boovuc 1,090]

Wow!

[squonk 38,905]

I don't think you can use a FLUKE to fix the carb! Use it on the gauges and lights!  

[nylyon-(Admin) 7,120]

On my 416, there's a bowl plug which can be removed.  When you remove that you have access to the main jet.  You can then very quickly and easily spray carb cleaner directly into the jet and it'll clean that and the float bowl.  It's a quick and easy job and doesn't require removing the carb or top of the carb.  Takes a few minutes and it fixed the surging on mine.

[Ed Kennell 35,735]

I hope you get her running  better  Horse.  I'd hate to see you out there FLOUNDERING around in this new snow that's coming.  

[AMC RULES 36,945]

On my 416, there's a bowl plug which can be removed.  When you remove that you have access to the main jet.  You can then very quickly and easily spray carb cleaner directly into the jet and it'll clean that and the float bowl.  It's a quick and easy job and doesn't require removing the carb or top of the carb.  Takes a few minutes and it fixed the surging on mine.

 

 

Quick and easy...

exactly where is this bowl plug located? 

[nylyon-(Admin) 7,120]

The 416 is snowed in at the moment, so I can't look.  But if I remember correctly (and we all know about my memory ) its on the front of the carb as sitting on the seat.  Or could be on the back? but it's definitely at the bottom of the bowl.

[thehorse 221]

Do you have a pic of plug location?

I like easy. I would PERCH myself up to look around and find it but a pic would be awesome.

Thanks

[nylyon-(Admin) 7,120]

Sorry, wish that I did.  I know it's there, you need to remove the entire air cleaner housing, but it's there on my 1994 416.  As mentioned in the prior post, I believe it's in the front as sitting on the seat.

[AMC RULES 36,945]

Do you have a pic of plug location?

I like easy. I would PERCH myself up to look around and find it but a pic would be awesome.

Thanks

 

Ditto...    

but, my little arms are so weary. 

[1977.d-160 1]

Throwing this out there as I've heard (not witnessed) it being a cause of similar symptoms:  check the governor spring.  Sometimes when they age there isn't enough tension and that can cause 'rev surging'.  Hope that helps - good luck!  <insert clever oceanic pun here>

[thehorse 221]

I will check the spring. Sounds plausible to me. Thanks.

[Damien Walker 223]

Late to the party as always.....but my 518H is sturgeon too! (couldn't miss that one). I've cleaned the carb but probably not the main jet...if it requires access via the bowl plug. I shall investigate over the weekend.

[Bak106 8]

Anyone know what size oil plug is on the kt17qs?  Cannot find any info! Middle of oils change and cannot not find mine