Hi Everyone,
This is the story of a problem that has plagued me for 3 engines now, so I'm probably going to ramble. I've cut it down to what I think are just the pertinent facts, but I can expand upon this to whatever length anyone who's interested would like.

I purchased a Sohn OMP bypass and an epitrochoid shaped, dual reservoir tank to feed both the OMP and my windshield washers. Since I did that, I have gone through 3 engines. I have never been able to figure out what I'm doing wrong. I replaced the first engine on warranty (80k kms), the second less than 10k kms later, and finally this one is giving up. I've always been careful about how it's driven, kept up to date on all servicing, check fluids, blah blah blah. I remember running the 2 stroke tank dry exactly once (on engine 2), and it could not have been for long, as I check it every time I gas up. So at most I ran it for a tank of gas without oil running through the OMP (bad, obviously), but probably less than that. After replacing the second engine I decided I would also premix, but run a little bit lower than normal ratios, as I'm doing both premixing and have the sohn, so it felt like overkill.

I figured out a couple years ago that my 3rd engine is also low compression, and have since stored the 8 and only driven it during the summer, and very infrequently at that. The other day, I went to use my washer fluid and it sprayed oil all over the windshield. Since it's driven so infrequently I thought I must have messed up and put oil in the wrong tank. So I got it home, cleaned the windshield and waited for the day I could take off the tank and clean it out.

Once I found some time, I set about the task of removing the reservoir and cleaning it out. So I take off the hoses, drain the fluids, and then grab some degreaser and submerge the tank in a bucket to get all the oil out. Afterwards, I figure I'll rinse it out with a hose, and let it dry for a couple days. While doing that I notice that despite only filling one side of the reservoir, there is water coming out the other. So I take it inside, and try to inspect it a little better. Noticing some odd markings on the wall that separates the tanks, I go and grab an LED light and stick the bright end in the oil side. Sure enough some light starts shining through what appears to be a crack in the wall. It's pictured below, but is a little weird to try and see, so I tried to highlight it a bit.

So the gist of this is, I think what's been happening is that over time the washer fluid has been leaking from the one side to the other. Meaning that I've likely been running washer fluid through the OMP for years. Slowly but surely destroying my seals. The only reason this final engine has lasted longer, is because I've been pre-mixing.


I know this is basically a "look at this idiot" thread, but I've honestly been entirely shaken by this as a car person. I had given up hope on ever recovering the love I had for this car. I love driving and working on cars, but I can't be rebuilding or replacing an engine every 25k kms. I felt like I had done everything wrong so egregiously that I couldn't be trusted with a rotary, maybe even with any vehicle modifications. Finally figuring out that this would be difficult for anyone to find has restored a bit of my confidence. I made a mistake by not inspecting the tank as thoroughly as I should have when I first got it, certainly. I shouldn't have put the sohn back on engine 2, let alone onto engine 3. But I couldn't really narrow it down to one specific mod (diy ecu tuning via Kane webinar, full exhaust, intake, sohn). I thought maybe my subsequent tuning on each engine that was the problem since I was flying solo on the actual tuning and it didn't make sense that it was the sohn, as it was always filled and seemed to be consuming oil.

Anyways, now the plan is that I'm rebuilding my engine so I can continue to enjoy my 8 for years to come. Maybe a supercharger if that junkyard eaton M90 guy ever updates his thread.

 

Yikes. Glad you figured it out!
What make of tank was it, so nobody makes the same mistake?

 

I hesitate to answer that question, as I don't want to disparage either the person who sold it to me (second hand) or the maker unduly. I omitted it for the sake of not stirring up a hornets nest.

I have no idea what caused this defect, and would not want to speculate. The opening appears to be jagged, like a crack or a puncture, possibly erosion (I don't know if washer fluid is corrosive to aluminum)

 

Unbelievable, glad you diagnosed it as soon as you did, that’s not your fault there was a hole in something you purchased. I would throw it in the trash and plan to have two separate tanks for fluids.

 

Thanks for posting this. "Aha" moments are wonderful, even when you kick yourself for not seeing it before.

 

Yeah, I know it's a tough find, but I'm still a little sore about losing 2 engines without figuring it out.

As for the reservoir, I'm going to see if I can't cut a hole in the one side and mount a clear plate to check what actually happens when they're both filled. I want to see what really happens, because as of right now I don't actually know how they would mix. Would the heavier washer fluid slowly seep into the bottom of the oil? Would the oil slowly seep into the washer fluid? Basically I want to figure out how this fails. Then I'll chuck it. I think it's likely a good idea to go with separate tanks for anyone going sohn for 2 reasons. First, no chance of failure like this. Second, even with the tubes on the side for level checking they were a pain to check because you couldn't really see anything in them without using a flashlight behind them. That second one is mostly a knock on the aluminum construction. I'll be trying to find one of the kits with 2 plastic tanks, so I can see the levels at a glance from now on.

No problem, this community has always been quick to help me, so it only feels right to return the favour. Plus, people here "get it" about these kinds of solves. Everybody has had something akin to this. A problem they couldn't find, finally solved.

 

The washer fluid, which is probably mostly water, even the sub-zero stuff, will definitely seek the lowest level and displace the oil above itself. So your tank's oil drain was likely getting the leaked washer fluid almost exclusively.

I would pull apart the oil pump also, just to make sure there is no corrosion that could cause further problems. Or, better just find a good used one.

 

your definitely not an idiot, but it only confirms what I’ve been posting and receiving return fire on about people choosing this route over just straight up premixing or adding premix in addition to regular OMP use. Because eating engines is going to be the end result if things don't go as were thought or intended.

I’ll probably even get some return flack on this post by the usual dive bombers about how this is a unique situation and so on. In reality, it’s exactly what I’ve been saying; you’re tinkering with the lid lock on Pandora’s box.
.

 

This is where logic took me as well, but I'm unsure of what that actually looks like when they are at comparable levels. What happens when you turn one of those oil/water drip toys on its side? As for an OMP inspection/replacement, I believe I have a spare OMP I bought from 9k years ago, so that will be installed when I get around to fixing everything up.

 

I have actually had this thought as well, and it's part of why it smarts so much to have this be the problem. I like everything about the Sohn in theory. Feeding 2 stroke oil makes more sense than engine oil. However, it does increase the number of things to check, the complexity of the solution, for what may be minimal gains. The argument/rumor that Mazda didn't go to a separate reservoir for usability reasons is at least somewhat convincing. I think anyone making the claim that one is objectively better than the other is likely basing it on logic or anecdote, rather than hard numbers.

That being said, I don't know if I'll ditch it entirely, but I am going to consider it. I do appreciate you trying to lead me to water, though.

 

Turbocharging is much safer, though. Many fewer points of potential failure. Engines NEVER get eaten. No sir.

 

I will spill the beans and tell you that is a ryan rotary "cofs" tank. Cofs seems to stand for clean oil feed system... so clean, that it washes engines off the face of Earth. Sold in/from UK for a hefty price of $420 + shipping + import tax. Could be an isolated case, could be the norm, could be just british engineering or lack thereof. I did kinda see it happening once I saw two tanks stashed on top of each other, but come on that should just be welded well enough.

 

Water and alcohol is corrosive to aluminum that isn't anodized. That is an issue in E10+ fuel systems as well.
all it takes to leak water is a pinhole leak in a weld.
Basically that's why I'm not a fan of more than one tank joined together where they can mix...

What did you do with the rebuild? I would make sure I used Mazda seals...

 

This is not true. I bought it from a forum member in the states, and unless he told me it was from a different vendor (and actually more storied one with regards to this forum), it is decidedly not from Ryan Rotary . I would delete that comment because you are wrong and a less than generous person could be construe it as libel.

I didn't have it rebuilt when I replaced the engines, both of them were replaced with Mazda Remans. Part of why I didn't put this all together was that around the first failure remans were in that weird spot where it was a roll of the dice if you got a good one. I figured the first reman grenaded because I'd heard it happens from time to time.

I figured this out after I had basically resigned my car to either being parted out, selling it, or waiting for some point where I have the ability to do an LF/GX swap from Keisler. It's been in that limbo for a few years now because I couldn't sell it as anything but a project in good conscience, and the amount I'd get for that would be less than less than what I could get for just a handful of the parts that are on it. Now that I have renewed interest and the go ahead from the SO, I'm probably going to contact Steve Wallace down in Vancouver to rebuild this one or buy/trade for one of his built engines. That's a little ways off though.

 

I've been having second thoughts on installing my new Sohn bundle on my new engine in part because of yours and others recent discussions about it, and Kyle at The Rotary Doctor expressing skepticism in a conversation we had.

I initially thought it was a good idea (and still do) in theory, but over the years doubt has crept in.

I don't think I'm going to install it during the warranty period.
I'm going to monitor the compression numbers as the mileage accumulates.
I'm going to hold onto it until then and maybe install it in a few years to see if there's any appreciable difference in the numbers afterwards.

If I'm able.

 

Is Steve Wallace in Vancouver a professional rebuilder that makes a living off it, or a side job?
If he has a business please lmk or link it in the rebuilders thread and I'll add him to the list.
Thanks.

I spent 3 years in the same situation with my LY undecided what to do.
I knew the engine was likely not salvageable enough for a decent rebuild after driving it for 2+ years with a failing engine.
It's in good shape otherwise and I felt it was worth more than I likely would've received for a shell offer, and no way I was parting it out.

I decided to be patient and wait for a new unicorn engine and lucked out.
Another year of unavailability and I would've likely let it go.

I haven't been checking to see if they're available yet, afaIk it's a supply chain issue and not that Mazda quit making them.

 

I know Steve is a professional engine rebuilder of some sort, but I'm unsure of whether he's still doing it as a business, or just because it's what he likes doing. I was looking to trade him for a motor a couple years ago after my buddy got a rebuild that Steve built and was selling. He's local enough to me that I can just drive down and get it done. The only other place is forcefed and somebody out in alberta, which are decidedly more of a pain in the *** or don't return inquiries.

It does look like mazdatrix offers remans, but the way they're listed on the website makes it seem like they're special order

 

Pineapple is a fairly close option as well...

 

I believe a good rebuild from Pineapple is now around $4400.
Well worth it if you research the process.

I was bugging the hell out of Rob at Pineapple once a month for updates on new engines with no success until Rob Babicki contacted me.
He claimed he had the last new factory Renesis engine in the U.S. bought from Pineapple.
Rob confirmed he bought it and is standing behind the 3 year warranty.

We had many email discussions prior to that about skepticism that advertised 'new' engines were actually new.

I would recommend them if anyone asked based on those interactions alone.

https://www.rx8club.com/series-i-tec...racing-273792/

Also see the note at the bottom of the header in the rebuilders thread from Kevin at Rotary Ressurection concerning owner expectations about rebuilds.

https://www.rx8club.com/series-i-tec...ilders-265177/

 

I’ve initiated contact with Steve recently to have a replacement engine built. He’s responding so must still be in the game. Local to me as well. I thought ForceFed was more interested in very high power custom builds so never contacted them. Leary of south of the border shipping issues so avoided Pineapple Racing but, could be an option. Wolfe Langley Mazda quoted $6,600 for a reman. They wouldn’t say what is new in the reman engine. I’m hoping to be a year away from purchase time.

 

Try contacting Rob at Pineapple about any issues shipping to Canada.
He's usually very responsive.
If you don't hear back from him, there's your answer.

 

'Steve from Vancouver' reminds me of an old Rick Dees radio bit I heard many years ago,
'Hans from Stuttgart' about him trying to get his BMW repaired.

I wish I could find it, I've tried, but it probably was lost in the ether.

He's at the dealership where a service manager is telling him their mechanic, Hans from Stuttgart says the part for his beemer has to be ordered from the factory in Germany and will take 2 weeks.

He asks to talk to Hans.
Hans comes out to talk to him and his voice is a heavily stereotypical African American.

Paraphrasing from ancient memory;
Hans: "Whatchoo need man?"

Dees: "What's wrong with my car?"

Hans: "You needs a Frusengladje switch man, we ain't got one here."

Long comical discussion ensues...

Dees: "Would $500 to buy your girlfriend something nice help?

Hans: "Lookee here, I found a Frusengladje switch under this pile of rags."

 

Let me know what you end up paying, if you don't mind. I'd love to have a rough idea. I'm sort of the same with Pineapple, even though I know they're great. I have the motor in my car and a "spare" that I want to either send both for rebuild, or parley the both of them into a slight discount on a good rebuild.