Why you MUST Pre-Mix.

RX-8888 · April 06, 2009, 11:18:48 PM

OK, most of the Jury is in on this one...
There are 2-3 issues that are causing engine failures in Series I RX-8\'s.

1. Carbon
2. Apex Seal Failure.
3. Damaged Side Seal.

1. Carbon Builds up because owners drive their cars at 3000-3500 RPM all the time, you must red-line a day (when engine is hot). Carbon can cause a sticking Apex Seal and Cause poor compressions.
There is a De-Carboning Technique that can help....can...

2. The MOP (Metering Oil Pump) is fatally flawed on the Series I RX-8, it only supplies oil (not enough also) to the corners of the Apex Seal..NOT THE MIDDLE, so over time the centre of the Apex Seal wears a concave face into the seal...causing blow back...bad compressions.

3. Some engines are breaking a side seal which does a lot of damage.

If your engine is OVER 50,000 miles the damage is already done, if you have a low mileage RX-8 I strongly urge you to ADD a Pre-mix to your FUEL TANK at a rate of 4 mils per litre of fuel...every time you fill up.
That is a 2 Cylinder good quality Synthetic BIKE OIL.

RX-8888 · April 06, 2009, 11:27:19 PM

OR add Pre-Mix is you have a new engine...

Will66 · April 06, 2009, 11:49:25 PM

Good advice, I\'ve just had a new motor fitted after a catastrophic failure of mine with little or no warning.

As for issue two, I don\'t believe the MOP is entirely to blame, however I think it\'s the oil feed to the oil injectors on the rear rotor, a lot of the engines that fail, mine included fail with loss of compression on the rear rotor. I\'ll be using protec R on my new engine to prevent just this problem. The R3 Engine has three oil injection ports, whereas the older motor has only two, I think the R3 motor will not suffer from these problems.

Gavin_RX8 · April 07, 2009, 11:37:12 PM

By 2 cylinder, do we mean 2 -stroke bike oil? As in what would be used in older scooters and 125\'s?

nicktyler · April 08, 2009, 08:45:28 AM

So am I to understand that as my car hs got 51000 miles on it it has been scrap for the last 1000 miles as "the damage is allready done" regardless of how it is performing?

Pre-mixing soundls like very good advice but as my car is over the limit do you have any practicle advice apart from gutted? Like should I have the engine pulled apart and have the apex seal replaced before everything blows, or is this just as costly as waiting and getting a full replacement?

I don\'t mean to sound short but I feel left a little empty and shunned by this claim as I am 1k over the get lost, too late mileage.

Also in an earlier thread on this forum you state the limit as 30000 miles and 2ml oil per litre of fuel. Thats a big difference

BlitzBoy · April 08, 2009, 08:50:43 AM

I think most of the failures I have seen is from granny driving by looking at the rx8 engines on Reworx garage floor, I think you will be ok Nick so long as you regularly rev the things out, plenty of 8s last over 100k.
Reworx say its mostly carbon build up from driving the 8s incorrectly (short shifting) and not reving them like they are suppossed to

nicktyler · April 08, 2009, 09:33:15 AM

Thanks for the reply Blitzboy. I feel a bit better now.

I certainly do rev it regularly and keep the oil topped up and fresh. Geff at Reworx did my last service at 50000 and seemed quite happy that it was in a good condition and drove well. I have it booked in for a hi flow cat and exhaust soon.

I am a full member of the RX8OC but for some reason thought this forum was all about rx7\'s. I will get on the members list soon as I can.

Glad to hear that will is back on the mean streets of Pompey as last I heard was a CEL and a bleak outlook.

RX-8888 · April 08, 2009, 09:56:57 AM

Quote from: Gavin_RX8;597060By 2 cylinder, do we mean 2 -stroke bike oil? As in what would be used in older scooters and 125\'s?

Yes, a good quality 2 stoke oil that mixes with Fuel.
I use Amsoil Saber Pro..it is 100% sythetic...

DO NOT USE CASTOR BASE OILS or Upper Cylinder Lubricants or TCW3 Marine 2 Stroke oils.

RX-8888 · April 08, 2009, 10:02:43 AM

Quote from: nicktyler;597093So am I to understand that as my car hs got 51000 miles on it it has been scrap for the last 1000 miles as "the damage is allready done" regardless of how it is performing?

Pre-mixing soundls like very good advice but as my car is over the limit do you have any practicle advice apart from gutted? Like should I have the engine pulled apart and have the apex seal replaced before everything blows, or is this just as costly as waiting and getting a full replacement?

I don\'t mean to sound short but I feel left a little empty and shunned by this claim as I am 1k over the get lost, too late mileage.

Also in an earlier thread on this forum you state the limit as 30000 miles and 2ml oil per litre of fuel. Thats a big difference

Sorry, I can\'t help that you are over or at a high mileage.

If you are the original owner approach Mazda Europe or your dealer for assistance.

Get a compression test done, if the results are good, then you can pre-mix and IMO it will help and you could extend life of your seals.

2 mils per litre is a minimum, I am now doing 4 mils per litre.

Really, if your engine is gone, you are better off having a full rebuild, you really can not just replace the Apex Seals as you might as well do a full rebuild , the extra cost is minimal or the same.

AMH · April 08, 2009, 10:09:47 AM

Quote from: nicktyler;597103I am a full member of the RX8OC but for some reason thought this forum was all about rx7\'s. I will get on the members list soon as I can.

No we love all things rotary. :Thumbs-up

I agree that when I spoke to my dealer about what to do to try and stop my engine going pop he said two things - keep the oil topped up and use the revs! They have an elderly RX-8 owner who actually gets them to take it out for a good blast every now and then!

I also thought I had to be careful about not going over 5k revs until she was warmed up because unlike the R3 the old 8\'s don\'t have any sort of limiter to prevent damage - but apparently they do! They just advertise this as a new feature on the R3.

I\'ve driven my car properly since it was new - always varying the revs and red lining most journeys. I honestly think she runs better now that ever - I just hope it stays that way as us Bankers can\'t afford a new car or an engine rebuild!

Gavin_RX8 · April 08, 2009, 10:09:56 AM

Based on what i\'m reading, i think i shal be experimenting with pre-mix albeit in small quantities at first, also going to switch to that oil that was developed especially for the rotory....cant remember what its called at the mo but its not much more expensive than the one i was using.

RX-8888 · April 08, 2009, 10:13:26 AM

Quote from: BlitzBoy;597095I think most of the failures I have seen is from granny driving by looking at the rx8 engines on Reworx garage floor, I think you will be ok Nick so long as you regularly rev the things out, plenty of 8s last over 100k.
Reworx say its mostly carbon build up from driving the 8s incorrectly (short shifting) and not reving them like they are suppossed to

While that is partly true, slow revving will produce carbon build up which kills the engine, you can not nanny a rotary.

The parts that is not correct is the Series 1 RX-8 MOP is Flawed, it does not lubricate the middle of the Apex Seal...this is a fact, why do you think Mazda added a 3rd injector in the middle of the Apex seal to lubricate in the new RX-8?, because they thought it was a good idea?.

Pre- mixing is the ONLY way to lubricate this area of the seal.

The highest RX-8 I have actually seen (I know the South African owner) was just over 200,000 KMs or 120,000 miles, his engine has just been rebuilt.
He is a rep and on road ALL the time and drives Long distances, Ideal conditions for a rotary.

If you do not red-line your engine at least once a day (when hot) you will have Carbon issues WELL before 100K, it just won\'t make that mileage.

Approx, 30% of all RX-8\'s in the US have had their engines renewed.
Some are on their 3rd.

RX-8888 · April 08, 2009, 10:19:36 AM

Look I am not trying to frighten anyone, knowledge is good, please use the Internet and look through the US Forums a little....

I own the Luxury version of the R3, you guys don\'t get it in the UK, it is the exact same engine as the R3 with the extra nozzle and two Electric Metering Oil Pumps, and I still pre-mix. 4 mils now per litre.

You will improve your engines compressions, better performance, lubricate all seals better and peace of mind.

RX-8888 · April 08, 2009, 10:21:57 AM

Quote from: AMH;597113No we love all things rotary. :Thumbs-up

I agree that when I spoke to my dealer about what to do to try and stop my engine going pop he said two things - keep the oil topped up and use the revs! They have an elderly RX-8 owner who actually gets them to take it out for a good blast every now and then!

I also thought I had to be careful about not going over 5k revs until she was warmed up because unlike the R3 the old 8\'s don\'t have any sort of limiter to prevent damage - but apparently they do! They just advertise this as a new feature on the R3.

I\'ve driven my car properly since it was new - always varying the revs and red lining most journeys. I honestly think she runs better now that ever - I just hope it stays that way as us Bankers can\'t afford a new car or an engine rebuild!

Shows how much your dealer really knows?

AMH · April 08, 2009, 10:25:02 AM

Quote from: Gavin_RX8;597114also going to switch to that oil that was developed especially for the rotory....cant remember what its called at the mo but its not much more expensive than the one i was using.

Oh no - not the great oil debate! :Giggle There is plenty of info about that on here Gavin so have a good read.

Quote from: RX-8888;597117If you do not red-line your engine at least once a day (when hot) you will have Carbon issues WELL before 100K, it just won\'t make that mileage.

I totaly agree with you on that one - definately the advise from my dealer (although some of us don\'t drive our rotaries every day - can\'t afford the petrol!) I don\'t need an excuse to open her up. At least twice a week I do a good 20 mile run and red line at least a couple of times each journey - part of the fun of owning a rotary!