The rear main seal on my HG42 leaked so bad that it would leave a trail of oil when operated. Finally the clutch stuck to the flywheel, so I pulled the whole thing apart. Installed a new rear main seal, clutch disc and TO bearing. Also replaced the pan gasket. Put everything back together - and it leaks in the same way. Parked in my shop, engine at idle, it will leave a puddle of oil the size of your hand on the floor in 5 minutes.
1XK3 motor runs fine, no blow-by from the oil filler or exhaust. Has good oil pressure and no unusual noises.
Any thoughts on what is wrong? I know the previous owner pulled the head off and re-used the head gasket, but I can't see that causing a massive oil leak at the rear main seal.
Which rear main seal are you using?
Quote from: Jethrow on May 04, 2015, 01:50:20 PM
Which rear main seal are you using?
Provided by Zimmerman's. Timkin package. Identical to the one removed.
The rear seal runs on a lip on the back side of the flywheel. Did you check the seal for fit on the flywheel before you installed it. That lip can wear over time and some times they are turned down and an under sized seal used. That is the only thing I can think of that might be your problem.
I removed a National 38220 from my IXB-3 and attempted to replace it with a Timken 455189 seal from Zimmermans. The result is about a .1" gap all around between the seal and the crankshaft journal. I ordered a National 38220 from NAPA to see if that makes a difference.
Jethrow
That sound about right. There should be a lip on the back side of the flywheel that goes over the end of the crankshaft. That lip fills that .1" gap.
Does your flywheel have that lip??
I wonder if there is a difference in that seal diameter between an IXK-3 and IXB-3, and an IXB-5? Just wondering if that seal from Zimmerman's is for an IXB-5 ? I really don't know.
When you had the flywheel off did you notice if there were two pins about 5/8" diameter in the flange that the flywheel bolts thread into. There are six holes in the flywheel/crankshaft, two of them should have these pins, the other four have the bolts that secure the flywheel to the crankshaft. If one of the pins is missing there would be a direct path from the crankcase thru the crank & flywheel to the clutch housing.
Scott R.
Ray, yes the flywheel does have a lip. I greased the seal side of the lip and bolted it back to the crank. Can't tell what the clearance is now. I'll have to wait until it's back together and running. This motor is planned for a test stand so it will be a while. I still need to drill the cap bolts for safety wire.
The flywheel is pretty dinged up. Don't know if I can just knock down the nicks with a flap wheel or if it need to be refaced. Thanks for the help.
Wow! Ring gear welded to the flywheel in eight places! I think that's what they call "overkill". Gonna make it tough to replace if it the teeth get chewed up.
Scott R.
Thanks for all the input, guys.
The seal I used is indeed a Timkin 455189.
My flywheel has no "lip" as illustrated in the picture. The seal area on the backside of the flywheel was polished smooth, except of a rough area maybe 1/8" or so where I suspect the lip should be. I polished that before putting the flywheel back on, although I did not remove any metal. in terms of making it undersize.
Both dowel pins were in place.
So now I have a dilemma.... what to do? The crawler isn't practical to use with it leaking oil like it does. And I suspect the clutch disc will soon be soaked........ and we know what happens then.
I don't mind taking the whole thing apart again, if it can be fixed.
Any suggestions at this point??
If your flywheel does not have the "lip" that is facing "up" in the picture above I would say you need a new flywheel. That lip is the surface that the seal, seals against.
(http://i1297.photobucket.com/albums/ag37/Lowspeedlife/Mobile%20Uploads/2015-05/4F554B80-D199-42AC-96AD-1FB906A7BAC5_zpswymrmcdu.jpg) (http://s1297.photobucket.com/user/Lowspeedlife/media/Mobile%20Uploads/2015-05/4F554B80-D199-42AC-96AD-1FB906A7BAC5_zpswymrmcdu.jpg.html)
In this very crude drawing I hope you can see that the "lip" on the back of the flywheel fits over the back of the crank shaft, if the "lip" has been removed, there is nothing for the seal to rub against to prevent the oil from slinging out. In that case a new flywheel would be the repair.
Scott R.
VW used a similar system and they had an O ring where the flywheel slid onto the crank, and a paper gasket on the end of the crank to keep oil from leaking out of the dowel pin holes. Could that be happening? Did you check the seal diamer on the flywheel lip before installation? Are there any oil galley plugs inside the bellhousing?
I misunderstood what you mean by the term "lip". My flywheel is identical to the one illustrated and does have a lip. I understand how the seal works, and apparently it isn't working properly in my case.
Good point about checking for other leak paths in the bellhousing and on the dowel pins, although I don't believe there will be anything found.
One question - when I installed the seal, I gently tapped it into place with a rubber mallet and block of wood. The face of the seal I took out was flush with the front of the crankshaft. The seal installed was about 1/8" deeper, i.e. behind the face of the crankshaft where it bolts to the flywheel. I am thinking that maybe the seal interfaces with the rough area at the end of the flywheel lip, and therefore doesn't seal properly. The shop manual doesn't specify if the seal is seated or just tapped in until flush with the crankshaft face. Thoughts?
My Hercules engine manual states that the seal body should extend 5/64" past the bore in the bellhousing. That would have to be measured from the back side of the bellhousing. Not easy to do with the bellhousing installed. So one would need to measure the length of the bore and the seal width and figure out how far in from the front the seal should be.
The manual states that this dimension is important!
Quote from: Robert Barbour on May 06, 2015, 03:19:18 PM
My Hercules engine manual states that the seal body should extend 5/64" past the bore in the bellhousing. That would have to be measured from the back side of the bellhousing. Not easy to do with the bellhousing installed. So one would need to measure the length of the bore and the seal width and figure out how far in from the front the seal should be.
The manual states that this dimension is important!
Thanks Robert. I spoke with Landis Zimmerman today about my dilemma.... he said the seal should be flush with the front of the bore and that there is no place in the bore for the seal to "seat", which I definitely felt when tapping it in. Maybe I pushed it right up to the back flange on the crankshaft. I agree that measuring, as you have stated, can be done.
So it will all come apart again and I'll keep the group advised of what the outcome is.
My manual is dated Sept 1952!! That was when Hercules still existed and supplied seals!! Today we get seals that are matched to the id and od of the old seals, not original seals from Hercules. Therefore the seal lip may not be in the exact same place relative to the front and back of the seal body. In the manual the diagram shows the seal back from the front face. However if Landis said it should be even that is what I would do. I rebuilt one 4 years ago and got the Parts from Landis and all work well. I don't remember exactly what I did!! I have another parts engine which is in pieces, I will look at it over the weekend and see how things look.
Looking through my parts I found a NOS bellhousing dated 6/14/7 , which I think is 1957, after OC 3 production ended, but while the 4 cylinder OC 4 was still in production.
This housing has never been used and has an unused seal in it, of the old leather type. The seal is flush with the front and back of the housing as it is with in a few thou of the same width. I measured the housing at .605 inches and the seal at .585 inches. The leather would contact the rotating surface for at lease the center half of the seal, a much larger area than a modern seal would.
Good info. Thanks for checking. The new style seal has a very small contact area. I will take everything apart again and report back to the forum what is found. I also will be looking for an alternative leak path while everything's apart. Maybe it isn't the seal.... perhaps something else.
Can you get a leather seal? They are much better for many applications such as this.
That is a good question Blake! I can not give an opinion on Leather seals as I have never seen a new one. All I have seen are on old equipment that has not run in a long time. That would be a good question to ask Landis, if they are still available he would likely know.
Leather seals are better for applications such as in crawler tractors as they are much tougher and can take more abuse than plastic or rubber seals. They do, however, always seep a very slight amount.
Chicago Rawhide seals were originally made from leather and were until recent times.
if it is leaking as bad as you say I would check your crankshaft for slop as well as end play and I would dial it to make sure the end is not bent as all of those can take a new seal out almost instantly. then I would look at that surface where the seal rides for irregularitys or grooves. I have had to use speedy sleeves on bad surfaces before. tip if you are to install a speedy sleeve use an electric pan and submerge in oil at 400 degrees for an hour before slipping it on. btw seal and speedy sleeve are matched set.
Quote from: eliwhitney907 on May 15, 2015, 12:35:26 AM
if it is leaking as bad as you say I would check your crankshaft for slop as well as end play and I would dial it to make sure the end is not bent as all of those can take a new seal out almost instantly. then I would look at that surface where the seal rides for irregularitys or grooves. I have had to use speedy sleeves on bad surfaces before. tip if you are to install a speedy sleeve use an electric pan and submerge in oil at 400 degrees for an hour before slipping it on. btw seal and speedy sleeve are matched set.
I've used speedy sleeves on small block chevy cranks, at the timing gear end.....but where would you get one for this application?
How does one check the crank for slop while in place? Thanks for the tips... this is a little out of my experience range.
You can check it for end play. If the thrust bearing is loose the mains probably are too, and a seal wont last long. If that is the case, the seal should have worked for a while, so thats probably not it. Only taking it apart will tell.
I looked at some of those pictures and that the seal matches to the flywheel is actually good as if it came to it you could replace the flywheel and have a brand new surface for your seal.
I am new to these herc engines but every time I have ever had to replace a seal there was always something either up-stream or down-stream effecting things. I always see a leaking seal as evidence of some other problem and start hunting.. again im new to these hercs. good luck and hopefully you get the leak to stop.
oh to answer your question when you have the flywheel off if I judge the pictures right there should be a gap between the bell housing and the crank. I would put a small pry in there and just see if it "klunks" when you exert a little force on the pry. it probably wont as if it did you woulda heard it when you had it running but it is an easy test. it is probably not bent either but we had the very end of a lugger crankshaft installed on a tug boat bend right at the flywheel when they hit a log. we went through a few seals before we figured it out.