John Deere - Briggs & Stratton Oil leak

[Neil B 1997 JD]

Hello -

I am new to this forum, so I hope I don稚 screw up my first post here. I own a 1997 John Deere Sabre Tractor, model 1646 Hydro. The Sabre line was one that JD built and marketed through some of the big box stores back then, I bought mine from Sears. It has a 16 HP Briggs & Stratton Vanguard engine (Model #28Q777, Type #0662-A1). Over all it has been a pretty good tractor for me with not many issues. I have always done all the maintenance on it and have even removed and repaired the hydro drive twice! I have never done any engine work on it though, beside change the oil. I have twice taken it to somebody for engine work.

Over the past couple of years, the engine has developed an oil leak that has reached the point I need to deal with it. Since the mowing season is done here in northern Indiana, I have decided I want to try to deal with this issue myself and have come here to this forum in hopes you all can guide me through this process. From what I can visually see it looks like maybe there is 2 leaks, one appears to be around where the oil fill tube connects to the engine. I am not sure how those 2 parts come together (press fit or threaded) but I doubt if that issue will be too difficult to fix. The other leak seems to be coming from under the engine. The underside of the tractor is just covered with oil and gunk. It appears the oil is leaking out the bottom of the engine and being slung all over the underside. My plan at this point is to remove the engine from the tractor and then try to determine where that oil is leaking from on the bottom. So I guess that is my first question, where do you think that bottom leak is occurring?



Don't have any pictures of the bottom of the engine.

Thanks,
Neil

 

[beenthere]

:welcome: to TBN

Hope we can give you a hand...
First I'd do, is put the engine model # into a search, and see if an engine manual with parts breakdown comes up..
Remove the engine and get it up where it is easy to work on.
https://www.partstree.com/models/28q777-0662-e1-briggs-stratton-vertical-engine/

Pics are good.. could not open the one attachment in your post. Try getting pics into .jpg format and uploading them with the "Go Advanced" button.

 

[Peter 315]

Most likely the crankshaft seal........

 

[MossRoad]

You could clean the engine very well while it's still in the tractor, then add some dye to the crankcase oil that shows up under black light. Run the tractor for a while, then shine the black light on it in a darkened garage or shed. It shows you where the leak is coming from.

You can usually find that dye and a compatible flashlight at auto-parts stores.

Good luck. :thumbsup:

 

[tomplum]

One thing to pay attention to is that the sump bolts aren't coming loose on these. A simple box end 1/2 wrench will do. Just simply check the few that you can get at to confirm that they are snug or not. The lower dipstick seal can actually leak a bit of oil if let go.

 

[Richard001]

Neil said:

I have twice taken it to somebody for engine work.

What work was done on the engine?

I have a 10HP B&S engine on an J.C. Penny tractor. The 16HP engine you have looks that same as my 10hp. Not saying it's the same, but has similar features. OH OK didn't see that at first. Your engine has OHV, while my engine is a flathead.

Some time ago, I removed the engine and did a rebuild on it. It also was leaking oil but it was coming out from the gasket area between the crankcase the the sump. At that time I also honed the cylinder, put in new rings and lapped the valves.

From your description, I would guess that, like someone already said, your oil on the bottom of the frame is most likely from a leaking main seal. If the seal is bad, you will want to check the bearing jurnal on the sump for wear.

As far as the oil leak at the fill tube, most likely it needs this: Seal-Dipstick Tube

Also make sure that the fill tube is anchored properly.

Richard

 

[Neil B 1997 JD]

Thanks for your responses. I think I fixed the picture link above. My initial thought has been the main seal as well and that is going to be the first thing that I look at once the engine is off the tractor, hopefully this weekend.

The work that I had done on engine before was replacing the head gasket and adjusting the valves.

I'll let you all know how removing the engine goes.

Neil

 

[oldnslo]

Some models of Briggs have a cover on the oil pump on the bottom of the engine. This cover is sealed by an O-ring that over time gets hard and takes a set which then allow them to leak. You have to pull the engine but very easy fix.

 

[Neil B 1997 JD]

So, I have made some progress. I removed the engine and have moved it down into my basement workshop so that I can more easily work on it. This allowed me to move the tractor back into my storage shed so that now I can get both cars in the garage. So I have looked the engine over pretty well and I think that it looks like the oil has been coming from the right front of the engine sump (right front as your sitting on the tractor), at least that seems to be where most of the oil is on the engine and the tractor frame (see pictures, keep in mind that these pictures were taken after I had cleaned much of the oil off).





I think the oil was maybe getting down into the frame of the tractor and seeping through that frame member (it's kind of U shaped) and then dripping onto the belts and that's what has caused all the oil getting under the tractor. It doesn't really look like to me that the main seal is leaking. I don't have a picture of the underside of the engine, but it looks pretty clean to me (for a 22 year old tractor). Also, the area of the tractor where the engine sits is fairly clean as well.



So maybe all I need to do is replace the sump gasket? Any thoughts? Is there anything else I should be looking at? Anything else that I should replace while I have easy access to the engine?

Thanks for your help!

Neil

 

[tomplum]

So you have a pattern of oil above the sump as well. Air cooled engines can be tricky that way. Even your leak from your drain and dipstick tubes can migrate to places you didn't think could. If you feel that the sump gasket is leaking, you need to know if the sump bolts had come loose. If they had, it makes these difficult to reseal and stay that way. Many of these did that.