I do beat on it. Second tranny second diff. Nothing like the redline buzzer to go with the starbuck espresso in the morning. BTW road course fuel mileage for me can range from 6 to 8 mpg (this was 10 yrs ago though). I

 

I'll answer this question because I have one of the very few fd's that had the original engine last over 100k using the the water cleaning method. Water steaming works, but I think some people are confused about what the cleaning is actually doing inside a rotary engine.

The cleaning does more for softening the carbon so the compression seals can continue to move freely and make max compression however, the steam isn't powerfull enough to remove the thick baked on carbon that's on the rotor face unless you do it excessively (like poman did). It's possible poman's excessive cleaning and final seafoam treatment caused a big carbon chunk to finally break away from the rotor face and damage the engine. I'm sure youv'e heard the numerious complaints of rotary's flooding. Sticking seals is the number 1 cause of this. You get too much carbon build-up in between the seals and they get stuck which lowers your compression. Back when my car had over 90k on it, I let it sit up in winter for 3 months without starting it. I finally went out in 35 degree weather and did 3 cold starts in under 3mins to see if I could make it flood. It didn't and fired up every time. When I blew the engine at 108k I opened it to find lots of carbon on the rotors but very little in the seal grooves.

Bottom line: If you want to do steam cleaning it's ok on occasion regardless of mileage. Doing it excessively is only safe if you start with a new or newly rebuilt engine thats virtually carbon free because now your slowing the carbon building process. Excessive cleanings on hi mileage engines can be dangerious since you don't want large chunks to breaks off. Oh yea, I always let the AWS do it's thing at 1st start-up. I know it's main design is to accelerate the warm up of the cat but it does have an additional advantage. It helps burn away the excessive gas that gets injected into the engine at cold start. When you blip the throttle to cancle the feature, all your really doing is allowing the excessive gas to stick to the rotor face. This allows for more carbon to build-up. Creating extra carbon is something you don't really want to do in these engine. Anyone saying that the AWS feature will harm the engine doesn't know what their talking about as my engine is proff with no unusual bearing wear.

 

^^Interesting, thanks for posting your experience.

Btw my idle AFRs are in the low 14s upon initial startup, no AWS needed. 870cc top feed primaries.

 

For some reason, I don't think the seafoam would have hurt anything. Although, as previously stated it's not really designed to be added to oil and driven very far. Usually, like ATF, it can be added to oil before an oil change (idled for 20 mins) to help break up gunk in the oil pan. Problem that DOES exist is breaking up too much gunk and stuffing up the oil pickup. Seen this happen in land rovers a few times... they are gunky turds - especially mine.

I've used seafoam several times in the past - but never on a rotary. It's a detergent that when ingested through an intake vacuum, then let sit, can really clean up a gunky top-end on a piston motor. Sticky intake valves etc... Even if your OMP passed some into the combustion chamber I really doubt it would have caused detonation... Definitely do as the rest have advised:

Change oil/plugs. Do a compression test. Check vacuum lines twice.

Good luck.

 

Missed this first read...

Sounds very possible; however, I hope this isn't the case.

 

Rear was 65 psi with even pulses. Front was 95 psi. Vacuum is 420-430 mmHg.

 

this was a piston compression tester? get it done on a legit rotary tester.

those compression #s don't really jibe with the vacuum.

 

Hey Rich do u guys have one? If so can u guys walk with it at the meet?
Khris

 

Hi Khris,

I will bring it to the Carlisi meet with me but I won't have time to do too many compression checks. If you're interested in having one done PM me

 

I'm curious, what eventually failed on that motor....soft (coolant) seal?

 

Coolant seal will not cause low compression.

From the readings provided, I would say that you have a chipped apex seal on the rear rotor that has caused just a slight amount of damage to the rotor housing. This will bring all the readings down for each rotor face.

Here is a customer's build with very similar readings/symptoms, the car still ran, he actually drove it to the shop. http://www.banzai-racing.com/2008_cu..._breakdown.htm

Failure was one chipped seal

 

Nothing better than having post come straight from the horses mouth. You guys along w/ Rich and Ihor are a great asset to this forum

 

No worries about gunk in an FD oil pan. Whenever I change it's half gas and 1/2 oil

 

Yep I burn about 5 or 6 gallons in a 25 minute session probably averaging about 80 to 90 mph I'm not sure what that adds up to but I'd say getting 5 mpg at the track is about average.

 

If this was related to my post, I never suggested they did. I just wondered what eventually failed on that poster's OEM engine.

 

Those readings along with the lumpy exhaust note (<---just remembered this from your original post) don't bode well. I'll bet if you closely watch the vacuum at idle it has a regular fluctuation

 

I get 15 road and 5 best on track

 

Back when I used to road race with my BNRs (I *really* need to get back on track this year) I would get right around 7 mpg.

 

Rich understood what I was saying, if you are getting 11mpg on the street you are romping on the car pretty much non-stop. In summer temps it really isnt that suprising you chipped a seal, I still dont think the blame falls on the seafoam. Either way, good luck in whatever direction you take, if you stay with the rotary get stronger more forgiving seals.

 

...... or get a simple water injection setup. I think if every 300+ rwhp had this you'd see almost zero blown motors.

 

im not seafoam expert but arent you suppose to suck it up through a vacuum hose into the UIM? ive used it before and had no problems... why would you mix it with your oil??

 

from seafoam's website: i wasn't sure about adding it to the oil system either, but it sounds like they think its alright. 100 percent petroleum product.

 

LOL because I have an Aquamist system that I bought 6 years ago and never installed. That might have saved the motor?

This was not a hot summer day. Temperature was 72F, air intake was 29C, coolant temp was 85C. Knock number was high though 89 when it's normally 25. boost on the PFC was 0.8bar. The plugs were brand new 9s all around.

I still think it's the seafoam being injected through the oil injector. This motor is a Malloy reman with mostly new internals 5 years old with 29K on it. 95 psi on the front is pretty good considering the age and abuse.

 

Oh, you're absolutely right Fritz. Was just tossing out info about what it's used for in "other" cars.

 

Considering the seafoam is basically the only part that is abnormal, I suppose this is where the research can/should be done.

Is it [likely] an additive such as seafoam would cause detonation in a rotary? I do know they don't fair well when detonation is a factor.

The odd part is that 8oz was added to the oil, which will make it's way to the combustion chamber, but in very small amounts. Would a very small amount diluted in oil still cause detonation?

- I know if you had the answer we wouldn't be here. I'm just kind of thinking out loud.

Best of luck.