Oil coming out fuel pump

[Olrecker]

Pull the head back off and get some 220-grit wet/dry sandpaper and a very good true flat surface like a tempered glass panel. Lay the paper on the flat surface and hold it. Place the gasket surface of the head on the sandpaper and slowly scrub it around to sand the gasket surface. Look at the gasket surface and you will see the results of high and low spots.

Sand it until it is nice and level all across. The old head gasket should be fine unless it lost some face material, if so, replace it. Reinstall the head and torque the bolts down equally in three steps to spec. Button it back up and adjust everything and run it to see if problem is resolved.

The next possible issue is the crank case breather has failed. It is rare, but it can happen.

I pulled thre head and sanded it for 1.5hrs. All by hand on tempered glass. It’s mostly smooth, except area outside bolt pattern that is pitted a bit but nice inside. Used 220 (5 sheets) w duct tape on the corners and one sheet of 600. Seemed to work better with some penetrating oil on the paper but shortened the life of paper and tape. I kept alternating the direction. All polished smooth. Waiting on new head gasket, old one separated

 

[slomo]

I pulled thre head and sanded it for 1.5hrs.

Takes less than 4 minutes. Give it a couple swipes. You will see how bad the head is warped. Start out with standard 150 grit. Get it flat with that. Then progress up a bit in grit. Last one I did was non wet/dry type paper.

 

[Olrecker]

Maybe the 220 was too light to start with but there was some residual gasket material I missed initially so that may have clogged the first piece but it was low on one side so I kept going until it was even except for the pitting which may have been mouse urine, not sure

 

[slomo]

What I've found is the wet/dry paper clogs quick on aluminum material. The plain OG wood type sanding paper worked better at 150 grit initial. That grit level isn't rough looking or feeling on the head gasket surface. I clean that up with 400 a few laps and call it good. Remember to turn the head as you lap/polish/rotate. So lap out on 150 and clean up at 400 grit. Works for me anyway.

 

[riceski@gmail.com]

Thanks for reading. I have a JD LA105 with a 19.5 single cylinder OHV. Replaced the head gasket, common cause, the mower starts and runs great but after a minute or two it starts bleeding oil out the fuel pump and breather tube. Wispy smoke when I pull the dip stick too. I adjusted the valves after the head gasket, took the fly wheel off and checked the valve which looked fine but there was no hole for oil to return to the crankcase. I am hesitant to tear it down for rings because it runs great otherwise. The mower has 180hrs. Anything else that can build pressure like that? Oil is slightly low from having come out and no fuel smell

I have seen bad rings do this as well.

 

[VRR.DYNDNS>BIZ]

With the breather hose blowing off of the air intake makes me wonder if the orifice in the air intake is clogged. Some of those engine in were the breather hose connects to the air cleaner elbow has a dome shaped insert that presses into the air intake and which the breather hose actually presses over to hold it in place. Sometimes when the breather hose comes off the orifice will come out with the Hose. If for some reason the hole in that dome insert is plugged would also cause your issues.

The breather may be not performing the check valve function, thus crankcase can be under pressure. I feel this system, its flow or head gasket is where the issue is but also the valve cover seal if bad can vent in as can any other gasket to crankcase vent in to defeat vacumn.

 

[grumpyunk]

Did you check the pattern pretty soon after starting to move the head around on the abrasive? Likely you would see an area on the side towards the pushrod chamber that was not getting shiny right away. Other areas possible. Either way, if you checked after removing the gasket remains and carbon on the head, you likely would have seen shiny areas where the head contacted and some area that still had not contacted the abrasive. The idea is to get full contact on all head areas which indicates the surface is flat(as flat as what's under the sandpaper).
Good luck.
tom

 

[Olrecker]

Did you check the pattern pretty soon after starting to move the head around on the abrasive? Likely you would see an area on the side towards the pushrod chamber that was not getting shiny right away. Other areas possible. Either way, if you checked after removing the gasket remains and carbon on the head, you likely would have seen shiny areas where the head contacted and some area that still had not contacted the abrasive. The idea is to get full contact on all head areas which indicates the surface is flat(as flat as what's under the sandpaper).
Good luck.
tom

I did and you are correct, the side with the pushrod chamber was still not shiny. I finished sanding until all that was left was some pitting outside of the bolt pattern. I thought mouse urine may have done that as it is caustic to aluminum. I plan on blowing off the head with an air compressor. I have the nee gasket and I was going to reassemble everything, including resetting valve clearance

 

[Olrecker]

No luck with new head gasket. Still doing the same bubbling out fuel pump.

 

[Red Good]

Got a pic of the fuel pump ? One side should receive the pulse from case pressure differential and the other side should only have gas in the chamber . Maybe the diaphragm is leaking side to side ?