803a Oil Leak after new seal ?

[paine]

I have an 803a that I picked out in 2017. I had to do a few things to get her up to snuff as it was an G-planet buy.

One of the issues that I thought I had taken care of was the front main seal.

I recently had a 5 day outage and the old girl was weeping some oil from the same darn seal. SO should I just try replacing the seal again, or maybe try the old trick of just recessing the seal into the gear cover a few MM in effort to give it a new sealing surface on the crank?

Is this a common problem? Do you think I have an underlying issue causing the leak?

Seal in question is #8 in the diagram.

 

[87cr250r]

Normally, a wire spacer is put behind the seal to get it off the groove in the shaft. Seals typically sit in a step in their housing so they can't be pushed in further. I would be surprised if the groove were so bad it would cause significant leakage immediately with a new seal. I would look very carefully at everything around the seal or suspect a faulty installation. Make sure there isn't any radial play in the crank.

 

[Guyfang]

I have repaired a lot of these engines. The front main seal is something I have never seen leak. Not once. I am sure it happens, but never seen it. So like mentioned above, I would look at the seal, to ensure you installed it correctly.

 

[paine]

Well she only has 400ish hours so I highly doubt the shaft has a groove from the seal. I bought the replacement seal from GMG and it was said to be an Onan part, but it looked different from the one I removed.

Hopefully it’s not play in the crank shaft!
That would be lame, but seeing as Guy said it is not common, that has me a little concerned.

Currently running the rig again right now, another rare outage, I’ll see how much it leaks in the AM.

Actually ordered another seal from GMG today, figured if I am going to disassemble it far enough to move the seal I may as well replace it and hope for the best. I’ll have to check for radial play in the crank while I am at it. But this is where Guy never seeing the issue is a good thing, seems unlikely to be the culprit.
My OCD doesn’t like oil leaks on my equipment!
My buddy has a parts 803 laying around, I was considering just yanking the front cover and using it on mine with the super slight chance that my cover has a slightly oversized bore for the seal in question.

Anyway. Thanks for the replies! I’ll update if I find something.

 

[Light in the Dark]

Its a pain in the ass to change out the $8 seal, but they can dry crack or just be faulty at the time of manufacture. I believe they are prone to fatigue with heat/cold cycles too. Not a bad part to have on the shelf. I've probably had to swap out 3 or so over the years, so definitely not a high failure rate item.

 

[87cr250r]

If you have dimensions I can get a part number for a Viton seal that won't dry out and crack.

 

[GopherHill]

When you change the seal, use crocus cloth or very fine emery cloth to lightly cross hatch the surface where the seal rides.

 

[Ray70]

2 other things, the seal should have a spring inside the lip on the inside, look at the old one to see if the spring somehow got knocked off.
The other thing I have seen is that the crank seals that come with the gasket kits from China are a tad too small on the OD and don't press into the t-gear cover very tightly and can leak. Supposedly you have an Onan seal, but just something to look out for when you go back in.

 

[paine]

Its a pain in the ass to change out the $8 seal, but they can dry crack or just be faulty at the time of manufacture. I believe they are prone to fatigue with heat/cold cycles too. Not a bad part to have on the shelf. I've probably had to swap out 3 or so over the years, so definitely not a high failure rate item.

Well, I guess it’s good to know that I am not the only one with a front main seal failure, but sad that I have to do it twice, because you’re not wrong, it is a time consuming process.

If you have dimensions I can get a part number for a Viton seal that won't dry out and crack.

I’ll try and remember to take some measurements of the new seal and front cover ID before I get too far into it, thanks. Like Light In The Dark said, wouldn’t be a bad idea to have one on the shelf.

When you change the seal, use crocus cloth or very fine emery cloth to lightly cross hatch the surface where the seal rides.

Noted, thanks!

2 other things, the seal should have a spring inside the lip on the inside, look at the old one to see if the spring somehow got knocked off.

The other thing I have seen is that the crank seals that come with the gasket kits from China are a tad too small on the OD and don't press into the t-gear cover very tightly and can leak. Supposedly you have an Onan seal, but just something to look out for when you go back in.

Thanks, I’ll take a close look at the “old” and new seal before I reassemble.

I hope the new part ends up NOT a Chinese part!

Maybe I’ll use a little sealant on the outside of the seal.





Thanks for all the help and ideas, I would rather not have to replace this same

seal once again!

 

[Light in the Dark]

I got mine from DP Equip in the Carolinas, worked well: https://www.ebay.com/itm/152849299868

 

[87cr250r]

Darn, I can almost make out the dimensions from that picture.

 

[Guyfang]

Seal tech data.

	CROSS-SECTIONAL SHAPE STYLE	SINGLE LIP
	ACCOMMODATED SHAFT DIAMETER	1 29/50 INCHES NOMINAL
	SEAL WIDTH	0 7/25 INCHES NOMINAL
	HOUSING BORE DIAMETER	2 17/100 INCHES NOMINAL
	CONSTRUCTION	SOLID
	PROPRIETARY CHARACTERISTICS	PACS

 

[87cr250r]

40x55x7 ok.

There are two options in Viton.


HMS5 is rubber covered single lip and HMSA10 is double lip

The single lip style is SKF part number 692464

The double lip style is SKF # 692466

 

[paine]

40x55x7 ok.

There are two options in Viton.


HMS5 is rubber covered single lip and HMSA10 is double lip

The single lip style is SKF part number 692464

The double lip style is SKF # 692466

Nice, now I just have to decide if I want to be the guinie pig and try a new seal lol.

 

[87cr250r]

If an 8mm wide seal will fit there is a CRW1 style which is a single lip with metal outer ring. These would be less expensive. SKF part number is 15821

 

[paine]

40x55x7 ok.

There are two options in Viton.


HMS5 is rubber covered single lip and HMSA10 is double lip

The single lip style is SKF part number 692464

The double lip style is SKF # 692466

Well, looks like I may be trying one of the seals that you found to be the same size.

I found two seal options one from GMG @ $40 shipped and one from eBay @ $15 shipped, so seeing as greenmountaingenerators.com listed the brand as Onan, I spent the extra money expecting an OE. Onan part. Well it was the same exact part that is on eBay for $14, same brand. eBay seal that I assume is a China made part as it says “designed in USA” on the box.

now to source the SKF seals that you found and see how it goes.


20 min later-ish update… ordered both SKF seals from summitracing.com, they are a special order and may take a few weeks.

 

[Farmitall]

Well, looks like I may be trying one of the seals that you found to be the same size.

I found two seal options one from GMG @ $40 shipped and one from eBay @ $15 shipped, so seeing as greenmountaingenerators.com listed the brand as Onan, I spent the extra money expecting an OE. Onan part. Well it was the same exact part that is on eBay for $14, same brand. eBay seal that I assume is a China made part as it says “designed in USA” on the box.

now to source the SKF seals that you found and see how it goes.


20 min later-ish update… ordered both SKF seals from summitracing.com, they are a special order and may take a few weeks.

Send back the the $40 seal to greenmountain and get a refund.

 

[paine]

Send back the the $40 seal to greenmountain and get a refund.

Yeah, I’ll call them up tomorrow, it’s both deceiving and a ripoff !

 

[jamawieb]

Its rare for them to leak but when they do, you have to get the new seal positioned exactly where the original seal was located. The crank will get paint and rust on the outside edge and if you don't recess it far enough the rust or paint will cut into the new seal. I learned after the 1st time I replaced and had a leak.

 

[paine]

I’ll be avoiding www.greenmountaingenerators.com
from here on out, check out this awesome customer service!!
This is copied from my email to GMG regarding the aftermarket (overpriced) seal:

“
Hi, I ordered a seal for my 803a that was listed as a Onan part. Unfortunately it is an aftermarket seal, I would like to return it as I have already sourced an OEM part. Thanks.

Please give me a call if needed”

GMG response:

“I'm sorry, but not really. The part we shipped fits fine. This was ordered from a supplier and they do not accept returns for small special orders.
GMG”


Can’t make this stuff up! I know it’s only $40, but with that kind of customer service response, I am going be talking with my credit card holder.