Onan generator carburator at prvparts.com

[cbilodeau]

Originally Posted by BFlinn181

...
Changing to a single weight oil should be fine for Florida and the desert, but starting it in a Montreal winter might be an issue.
....

I leave Montreal let say on Dec 16 and plan to be at my destination in south Florida on the 19. If on Dec 16 the weater is too cold I will simply not start the generator since my heating is all LP.
If ever I am in a bad situation where I will need to start the generator, I read that I should simply start the generator without a load for a few minutes so that the engine would be at idle until it warms up. I should not use it on the road if it's too cold but only when parked. So instead of changing my oil twice during the trip (nobody would do that anyway), I will simply try to be careful.

Originally Posted by BFlinn181

I couldn't find evidence of your definitive statement, "This oil(straight 30w) has no detergent" There are many myths and old beliefs repeated on the internet. The idea that a small engine with no oil filter should only use non-detergent oil is one of these old myths.

Maybe it is a myth. But I see people on the web that say they worked for 25 years in a garden tractor -generator repair shop and they always use 30SAE. They says that these engine are anyway always used in hot temperature.

BTW, Onan also seems to be saying SAE 30 is the way to go for this engine at temperature higher than 100F.

I understand a 15W40 can appear as a 15 at low temperature and as a 40 at high temperature but still when I look at graphs for this small engine application on the web they show the specific temperature range for each oil and the 15W40 graph goes lower than straight SAE 30 oil. So it is possible that the detergent or the mixture or the additives have some issues in small engines on very hot temperature? I don't know but on some websites many people working on very old car claim that the old engines have leaking oil in the air filter with 10W30 and they fix it with SAE 30.

I don't want to contredict you. You have a lot more knowledge than I do. I will try SAE 30 and see next summer (august and september) if it fixed my problem I will report on IRV2.com. I will go that way not because it is the best next step but simply because it is the cheapest.

P.S.: Some people working in tractor garden shop say that the only situations where they don't use SAE30 is for the tools that run at high speed right from startup. The reason is that SAE30 at lower temperature should be run at idle until the engine is hot.

See this graph for Briggs & Stratton small engines :


They say that a mower would consume more 10W30 oil at temperature above 80F. And for my generator Onan in the operator manual does not recommend 10W30 above 80F either. We have a hint here, if it consumes more oil, it probably explain why above 100F last summer it leaked so much in my air filter. If I recall the temperature was 47C-51C which is 116F-121F. My engine could not be at a lower temperature than 116F if it was 116F outside.

Conclusion: 10W30 is no good above 80F and I had 116F to 121F. That is 40F over.

[cbilodeau]

See this chart here for a small John Deere engine:

It says that SAE30 can go up to 50C (122F) while 10W30 goes to 40C (104F). In the desert the temperature went at 121F.

[cbilodeau]

Base on my readings I came to a conclusion. This conclusion is only mine and no expert said anything about it yet.


Here are some facts before I give my new conclusion:

1 - Normally it is not a bad idea to change the oil of an engine at leat twice per year. At spring it is more important since a oil at cold get thicker. This is why they say we should never store oil in a cold garage. But nobody recommends to change the oil twice a year for a small engine to my knowledge.

2 - If we use SAE30 the engine get no detergent and can get cloggeg more easily. If we use 15W40 we get detergent and the engine stays clean.

3 - If we run at high outdoor temperature SAE30 is the best oil. Otherwise 15W40 is very good up to 100F.



My new conclusion:

One could decide to use 15W40 for half a year (when temperature is < 104F) and SAE30 for the hottest period of the year when he could encounter more than 104F outdoor temperature.

In my case, I have 5 children. We can travel only 3 to 4 full months. This is mi-december to mi-january in the winter and july-august-september in the summer. In the winter we go Florida which is not so hot and 15W40 should be ok. It means I would put 15W40 or 10W30 or 10W40 on october 1st when I come back from my summer trip and would put SAE30 in april when the snow is gone.

Why would I do that? My Operator's manual says I have to "Remove Cylinder Heads and Clean combustion chambers" every 500 hours. Newer version of this manual say "Clean Cylinder Heads of Deposits" every 1000 hours. If I want to avoid this cleaning I guess that having 15W40 for half of the running hours could help me out. I suppose the engeneer went for the worst case scenario where people use only SAE30 straight.

P.S.: If this solution is too expensive, one could decide to switch his oil and reuse it next winter. Oil can last 150 hours. If we write on the cans the number of hours we should be ok.

[BFlinn181]

Cylinder head deposits are caused by incomplete combustion of gasoline. Oil with detergent has nothing to do with these deposits or the reduction of them. Oil stays in the crankcase and the rings are supposed to prevent oil from getting into the top of the cylinders.

[cbilodeau]

Originally Posted by BFlinn181

Cylinder head deposits are caused by incomplete combustion of gasoline. Oil with detergent has nothing to do with these deposits or the reduction of them. Oil stays in the crankcase and the rings are supposed to prevent oil from getting into the top of the cylinders.

I see. It is simple logic that make sense. Should we bother today with the cleaning of the cylinder head with the gasoline they sell?

I still think the oil alternate scenario is useful to keep the rest of the engine from clogging.

BTW: I read that Non-Detergent is usually a standard in straight SAE 30. Older engine and small engine do not have such close machining when they were built so they say it is why SAE30 is just fine.

Some pictures of SAE30 bottle saying non-detergent:

[BFlinn181]

The steady rpm speed of a generator, the fact it's a carbureted engine instead of computerized fuel injection, all contribute to the reason cylinder head removal and cleaning is recommended after 500-1000 hours of use.

[cbilodeau]

Originally Posted by BFlinn181

The steady rpm speed of a generator, the fact it's a carbureted engine instead of computerized fuel injection, all contribute to the reason cylinder head removal and cleaning is recommended after 500-1000 hours of use.

I suppose there are some "non recommended" little bottle we can buy to avoid this?

Otherwise is this a big DIY job?

I ask the question because so far everybody around my motorhome had a genset working except me. But if mine can do its job I should accumulate hours rapidly. I had so much problems those 3 years: worn gas pipe over the gas tank, then electric gas pump, then two major oil leaks into carburator and finally carburator broken by my bad manipulation being a newbie at engine.

[cbilodeau]

Twinboat,

I really don't mind what people think about me in my real life and in my virtual life. My only consideration is to get to my goal.

I have reached my goal with my thread. I will know better my genset and most RVist are newbie like me and they have to be able to manage it correctly.

Anyway, what I want to tell you is that we should not tell publicly that we will not post on someone since it will stop newbies from asking questions.

The real "ennemies" for our wallets are the garagists, the Camping World bills, the expensive suppliers, the towing truckers. They all want our money and our lack of expertise is their best friend. The more we work together the better we fight this war.

I will keep posting what I learn so that everybody can share. Nothing will stop me. I will post on your posts and without any bad thinking.

We are in the same camp.

BTW: I will get my gasket, the supplier knows the community is reading and he shipped it immediatly with a tracking number. Thanks to you. We are strong together.

[Patti Jean]

Cbilodeau,
30 weight Pennzoil will work well in your Onan. I have owned a 1999HR V10 with a BGM onan 5500 since 2011. I use Pennz Platinum 5w30 in the V10, and regular Pennz 30w in the gen. Pennz 30w is a detergent oil. If carbon buildup is a concern, the best thing you can do for the V10 and the Onan BGM is to use 87 octane tier 4 gas. I have an aux. 6 gallon tank for my generator plumbed with a Y valve (switchable to either aux. tank or motorhome tank) to run off of occasionly with Seafoam added (1 pint to 6 gal) to help keep the carbon clear in the generator.

[cbilodeau]

Originally Posted by taxiboo

Cbilodeau,
30 weight Pennzoil will work well in your Onan. I have owned a 1999HR V10 with a BGM onan 5500 since 2011. I use Pennz Platinum 5w30 in the V10, and regular Pennz 30w in the gen. Pennz 30w is a detergent oil. If carbon buildup is a concern, the best thing you can do for the V10 and the Onan BGM is to use 87 octane tier 4 gas. I have an aux. 6 gallon tank for my generator plumbed with a Y valve (switchable to either aux. tank or motorhome tank) to run off of occasionly with Seafoam added (1 pint to 6 gal) to help keep the carbon clear in the generator.

Top Tier gasoline
On wikipedia read this text.
Another article here.

I knew nothing about Top Tier. Everybody should know about it. I will print the wikipedia gas station list (click the link above) and keep it in my glove box for my cars and my motorhome.

During our trips we move a lot and most of the time we fill at Costco and they are Top Tier certified. I get 2% reduction with my costco credit card and Costco on gasbuddy.com is normally the cheaspest in each town we go.

They say that to be certified a cie must have all its stations and all its gasoline grade to be Top Tier.

Thank you for this good information.

V10 oil 5W30 vs 5W20
Ford now recommend 5W20 for the V10 so this is what I use. The lower we can go, the longer the engine could last and 20 is lower than 30. Gives also less friction. I buy full synthetic at Walmart, they have the cheapest to my knowledge. I am no expert at oil, I am giving what I have read.

I use synthetic all the time because it create less friction which is better for an engine we want to keep for a long time.

Seafoam
I will install a plug to connect a hose to an external gas tank to be able to use Seafoam like you do. I suppose once or twice a year.

SAE 30 in your generator
Do you have any feedback to give about cold temperature with the straight SAE 30 oil in your generator? Starting in cold weather? Do you wait for warm-up before you put a load?

Thanks

[Patti Jean]

I run my generator about once a month, all thru the year. 30w oil has never given me a starting problem in the cold winter months --- and it does get really cold in Oklahoma in the winter. I switch it over to the aux tank when doing the generator exercise. Start it and run for about 5 minutes and then load both the ac units for about an hour. Also run the RV engine for about the same time. It may be somewhat harder to crank the Gen further north. This works well for me, and I have never had any problems with the Gen or the chassis engine. The seafoam is a good fuel stabilizer and it and the tier 4 gas really seems to keep the fuel system/ carbon buildup problems at bay. I only run the aux tank for exercise for the Gen. Also I pull the plug in the bottom of the gen muffler about once a year while exerciseing the Gen to blow the carbon buildup out of the exhaust system. BTW the manual for the 1999 ford v10 calls for 5w30. The later models went to 5w20.

[BFlinn181]

Periodically running a generator under load is good exercise for the engine and the brushes of the generator. Idling a truck engine without load is a very bad idea. Unless the engine gets up to operating temperature, condensation will collect in the oil and remain when turned off again. Many discussions can be found on the forum about not running the engine at all is much better treatment of the engine.

[Patti Jean]

B Flinn
You make a very good point about condensation. I always run the chassis motor till the exhaust is hot all the way to the end of the tailpipe, and no drip. For me there are other considerations also. I run the dash air, move the trans thru all the gears, and use the brakes to keep everything moving and lubricated. During this time I also drive the coach about 20 miles. I have it parked at home so this is an easier task for me. I hate to leave it unused and not moving from November thru March.

[cbilodeau]

Originally Posted by taxiboo

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BTW the manual for the 1999 ford v10 calls for 5w30. The later models went to 5w20.

TSB 02-1-9 changed the recommendation for the F53 oil engine. Here is the PDF, or here or here. About 5W20 they say: This oil is an improved formulation to improve fuel economy.

Thank you for the feedback for the winter use of the generator. I will go SAE 30 and use Sea Foam like you do.