About 3 months ago I was on a cross country trip on my 18 FLSB and she started puking oil through the air cleaner, maybe about 1/2qt every 400 miles. A little more than twice my usual oil usage. Had it checked at Battle Born Harley in Carson City,NV and they really didn’t see anything obvious short of diving deeper and checking compression and leak down, which they couldn’t do on the day I was in because of limited staff. So changed oil back to Syn3 from Amsoil hoping maybe bike just didn’t like Amsoil for some reason. Nope; similar oil usage. Tech’s advice was to the effect of as long as you keep oil in it, you wouldn’t hurt the engine any more than it was already hurt.
Long story short, continued the trip but did stay more on the interstate than backroads just in case something would catastrophically go wrong, which it didn’t. Get home and into local shop and compression a little low on front cylinder and leak down not good on either through the rings. Tearing down motor, and they’re not sure why but the rings weren’t sealing as they should. No signs of sumping or overheating. Ended up needing to rebuild. Stayed with the 107 but did upgrade to a SE torque cam and the upgraded 2020 oil pump
My question is how many early M8 Softails out there have ended up having major engine issues similar to mine?

 

What you were experiencing I would think was sumping, which is pretty rare for the Softails with the dual counter balancers. Were you experiencing a loss of power? It may be that your oil pump just wasn’t scavenging enough, but not so much as to produce full on sumping. Some members have said that they never fill the oil tank above the halfway mark. They have encountered the same issue you did and leaving the oil level below the halfway mark is what cured it. What they should have done at Battle Born is drained the flywheel sump to see how much oil was accumulated in it. Maybe they did and you just didn’t mention it or they didn’t tell you.

I think you have done things that will take care of the issue if it was related to scavenging, mainly installing the latest oil pump. I would keep the oil level below the halfway mark just as a precaution.

For the most part, issues with the M8’s are not prevalent. The pre 2019 touring models had problems with sumping, so much so that the MOCO redesigned the oil pump a number of times. Transferring oil from the transmission to the primary was also a problem with the touring models. This still happens at times, but it is not a major problem anymore. Again, this isn’t a Softail issue. The other thing that has been a problem is the compensator ramps failure. This has been addressed by aftermarket companies by making them from better compound alloy metals. I’m not sure it is something that was widespread, it may have just been a bad run when the ramps were being manufactured. The bad thing is that a ramp disintegrating can wipe out the engine cases. I personally change this on my bikes as a precaution, I can’t say it is absolutely necessary.

Good luck with your new build.

 

When I got home, I did pull the crank position sensor. Maybe 3 or four drops came out at most. There could have been a small amount of power loss but it was minimal.
And cold I would barely have oil on the stick. Maybe about 1/4 to 1/2 way when hot

 

I had some engine issues with my 2018 M8 Softail. It was sumping oil. During an extended ride the engine would run so hot I could barely keep my foot or leg near the bottom of the motor. It would also lose power and sometimes shut down and run on one cylinder. It was repaired under warranty with an updated oil pump. I used it as an opportunity to do a stage II upgrade and only had to pay the cost of the cam. No problems since the upgrade.

In addition to your oil pump upgrade, you might want to address the crankcase pressure by venting the dipstick or the transmission cover.

 

2019 Softail Slim. +58,000 miles. No engine issues.
Engine is stock with the exception of

• exhaust
• Screamin' Eagle High-Flow Air Cleaner Kit
• a canned Dynojet Power Vision tune

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