Okay guys... so here is my story and reason for considering an engine cleaning procedure. In a nut shell, I bought the car about a month ago, the car had a reman installed with what is now approx: 16k miles. The secondary turbo was not working due to a vacuum leak which the seller I believed had mistaken for what he had told me was a slipping clutch. Due to the nature of how the secondary turbo would spool up intermittently I could see how somone would easily mistake it for a clutch that is beginning to slip. On top of that, the car had a clogged ndownpipe that was causing considerable water temp issues. It was at this point, and after inspecting the sparkplugs, that I decided the engine could use a good internal combustion cleaning.

On to my little experiment, so far I am finished with phase one...

I did two compression tests today, both were done on a warm engine approx 10 to 15 minutes after shut down...


These were my base line compression tests: (Oil has approx 2,500 miles of use)
-Test 1: Rear rotor 101 psi, Front rotor 106 psi (Vacuum 17 inches)
-Test 2: Rear rotor 100 psi, Front rotor 108 psi (Vacuum 17 inches)

Following the base line readings, I did a steam clean of the engine. I decided to go with the steam cleaning method versus sea foam primarily due to the fact that I have not read enough testimonials / experiences with this product and its effects on the engine long term.

My steam cleaning method was as follows: I used half a gallon of distilled water that was hooked up to the nipple on the UIM that runs to the pressure release valve (the black OEM bov). With my friend holding the jug of water and me in the drivers seat, he dropped the vacuum line and instantly the RPMS on the car will drop and the car will nearly stall (I kept the RPMS @ around 4k, periodically redlining the motor.) I did this until there was no more water left in the jug and kept revving the engine for roughly 10 more minutes.

I let the car idle and it seemed stable so I shut the car down, let it cool for 15 minutes and did my second compression test.

These were the compression numbers and vaccume following the Steam cleaning method.
-Test 1: Rear rotor 111 psi, Front rotor 120 psi (Vacuum 19 inches)
-Test 2: Rear rotor 110 psi, Front rotor 120 psi (Vacuum 19 inches) - This was done an hour after the initial compression test

So... following the steam cleaning method, the compression on both rotors increased by a minimum of 10 psi and the vacuum increased by 2 inches.

Following this process, I changed my oil with the usual royal purple 20w40 but I added a little twist (ZDDplus) addative...

I will be doing another compression test in 500 miles...
spoolage is online now Report Post Reply With Quote

 

wow cool. Thats very awesome. maybe do another compression test in a week to see if the compression hasnt dropped.

 

I will be doing one every 500 miles till I hit 3,000 miles, then I will do another steam clean and do more compression tests.

I need to have enough samples that this can be somewhat statistically viable. I did a ton of pre oil change, pre ZDDP compression tests as well. I am trying to see if this zddp discussion really has any positive effects.

I am logging my car, taking vacuum readings and monitoring compression @ 500 mile intervals. I am looking for any positive changes that could be related to using ZDDp.

I did 6 compression tests on the last oil change to get a mean score for the front + rear rotors.

I will do 6 more on this oil change ( w/ zddplus ) in the mix...

I just wish I had a wideband =((

 

You also need to report the cranking rpms for each test because they will affect the readings. The FSM has an adjustment table. Recording water temperature (and oil temperature if you have a sensor) would not hurt either.

 

All that is being logged via datalogic

 

So were the cranking rpms the same for both tests? Also, were the idle rpms the same for both vacuum readings?

 

results?

 

what kinda compression tester are u using? poormans or mazda?

 

It sounds a lot like you are doing the same treatment written/suggested by Rotary Resurrection on their website. Here is the procedure they suggest:


http://www.rotaryresurrection.com/3r...injection.html


WATER INJECTION TREATMENT FOR ALL ROTARY ENGINES

When talking about rotary engines, carbon buildup is a common problem brought up. I have a writeup elsewhere in the tech section of internal engine damage pics, showing the effects of carbon buildup. A good way to combat this harmful effect is to inject water into a running engine as a matter of maintenance (note that I am not referring to water injection as a method to assist tuning and combat detonation, but rather as a maintenance procedure). By allowing an idling engine to injest a small amount of water, it hits the rotor faces and turns to steam, cleaning off carbon as it does. The more regularly you perform the maintenance, the cleaner your engine will remain. The procedure (I believe) was originally brought to light by Rob @ Pineapple racing, so please note that I’m not trying to take credit for this, only spreading the information for use by individuals.

Note that this should in no way harm an engine in good health. Water doesn’t combust, but it doesn’t harm any internals or sensors such as plugs or 02 sensors either. The engine will misfire and stumble during the time water is injected, this is normal. You will have to apply throttle to keep the engine above 3000rpm during the injection.

To perform this, I use a gallon jug of water and a long vacuum hose, say 3 feet. Though this is different for nearly every year and model, the underlying goal is to find 1 or 2 vacuum nipples on the intake manifolds after throttle body, preferably on the lower intake manifold so that the water can run straight down into the block. You want to feed both front and rear rotors evenly…generally you have 4 intake runners, 2 for the front, 2 for the back. Some engines have one nipple that can feed both (s4 turbos, for example, have one above the BAC valve that is evenly split between F and R primary runners). Some engines (fd’s and s5 na’s for example) have 2 separate nipples that can be teed together externally (vacuum hose and tee) to evenly feed both rotors.

With the engine running, remove the vacuum cap or lines that used to cover the nipple you’re using. You might have to apply throttle, so the engine doesn’t die due to a vacuum leak. Insert your hose(s) onto the nipples, and bend the hose somewhere in the middle by hand so that it seals off the air intake. Now, dip the end of the hose into the water at the bottom of the jug. Either grab the throttle linkage and rev the engine up, or have an assistant hold the throttle for you, above 3500 or so. Release your crimp on the hose, letting the engine vacuum suck water in. The engine will begin to shake and misfire, apply throttle as necessary to hold 3-4krpm and keep the engine from dying.

Expect a lot of steam from the exhaust. This is normal. I let the engine drink the whole gallon at once. When it’s done, it’ll begin to clear up slowly, and you can gradually let off the throttle and replace the original vacuum hoses/caps.

 

Hey spoolage, any updates?

 

been wanting to try this on my car for awhile now, good to hear somebody else has tried with excellent results.

 

It would be great if someone could point out two good vaccum source's that lead to each rotor. On the LIM a lot of the nipples are not vaccum sources. On the UIM, I was thinking of just using the nipple on the left for my boost gauge and the nipple on the right for the stock bov and hope the water divides evenly between both rotors.

 

Great results. What engine rpm were the comp tests performed at?

Keen to see results of the next tests. Keep us updated.

 

Yeah! A higher compression might increase the value of the motor im pulling substantially. Can someone post a pic of which nipples to connect to?

 

The small ones on the turbo side of the Plenum, next to the runners

 

^^^umm, could you still post a pic, just because I think I know what you are talking about but not too sure.

 

Its the two on the passenger side of the UIM one is connected to the stock BOV(ABV) line and the other is usually capped off.

 

This sounds great. I will do this regularly one I've built my new engine Even in 2500km my old engine built up a fair bit of carbon.

I'd be interested to see how effective the steam is... would be good to get the rotor up to operating temp (but external to an engine) and dump water onto it and see how easily the carbon comes off.