Mazda Rotary Club

Cars by Model Type => 3rd generation RX-7's => Topic started by: Hi RX7 on October 13, 2008, 08:11:25 PM

Title: Engine re-build frequency.
Post by: Hi RX7 on October 13, 2008, 08:11:25 PM
Just browsing through a number of recent threads I have noticed that the frequency of engine re-builds is quite high. So I was wondering what the average time/mileage is for RX7 owners on this forum. For instance mine went within my first year of ownership and from other threads/postings there seems to be at least another six cars off the road at the moment in need of a re-build so what is the full figure?
Title: Engine re-build frequency.
Post by: karl_tate on October 13, 2008, 09:09:12 PM
IMO i think that there is far too many variables to put a timeline on a engine.
Title: Engine re-build frequency.
Post by: m1tch on October 13, 2008, 09:11:50 PM
2nd gen = average 100-125k
3rd gen = average 75k

More boost = lower engine life
Title: Engine re-build frequency.
Post by: Rzla on October 13, 2008, 09:48:50 PM
Quote from: m1tch;544557More boost = lower engine life

So true ... the same applies for a piston engine.
Those who think tuning a piston engine doesn\'t make it less reliable are kidding themselves.
Any type of engine you tune is susceptible to engine failure, except the cost of rebuilding a skyling gtr lump is 3 times the cost of a rotary rebuild.
It depends what routes you take to keep the car safe, ie water injection/ignition amps etc.
Title: Engine re-build frequency.
Post by: BenLewisMav on October 13, 2008, 09:55:09 PM
I hope thats 75,000kms..
Of course David you don\'t hear so much about the ones still running fine with no problems, so keep that in mind lol :D
Title: Engine re-build frequency.
Post by: dthebuk on October 13, 2008, 10:05:38 PM
Quote from: BenLewisMav;544584I hope thats 75,000kms..

pretty sure its miles
Title: Engine re-build frequency.
Post by: Rzla on October 13, 2008, 10:11:37 PM
Quote from: BenLewisMav;544584I hope thats 75,000kms..
Of course David you don\'t hear so much about the ones still running fine with no problems, so keep that in mind lol :D

Exactly who is going to put up posts about how well their engines are running?
You have to put it all into perspective, people will obviously post when the engine is not running well, to find out what the problem is etc ... but that does not mean more run bad than run well. It is quite the opposite.
Title: Engine re-build frequency.
Post by: m1tch on October 13, 2008, 10:17:55 PM
My FC is at 81k miles with compression ratings of 7 all round :)

(http://i93.photobucket.com/albums/l49/m1tch_2006/rotarywh6.jpg)
Title: Engine re-build frequency.
Post by: Hi RX7 on October 13, 2008, 10:56:18 PM
Just to get things into proportion it would be a good idea to find people who have run their cars for long periods without incident/re-build and this thread is in no way knocking the reliability of the rotary its just to really get a picture at this moment in time as to how many are off the road due to major engine failure. From my own point of view I would love to keep the rotary in my RX7 for as long as possible and although my mind is made up regarding the next move engine wise I was just checking to see if say someone was really unlucky and had perhaps had to re-build more than say twice in five years.
Title: Engine re-build frequency.
Post by: BenLewisMav on October 13, 2008, 11:11:29 PM
Quote from: Rzla;544593Exactly who is going to put up posts about how well their engines are running?
You have to put it all into perspective, people will obviously post when the engine is not running well, to find out what the problem is etc ... but that does not mean more run bad than run well. It is quite the opposite.

Yeah that\'s precisely what I was saying (I\'m not sure if you misread it? We kinda said the same thing!)..
Title: Engine re-build frequency.
Post by: BenLewisMav on October 13, 2008, 11:19:00 PM
Quote from: David Wiltshire;544606Just to get things into proportion it would be a good idea to find people who have run their cars for long periods without incident/re-build and this thread is in no way knocking the reliability of the rotary its just to really get a picture at this moment in time as to how many are off the road due to major engine failure. From my own point of view I would love to keep the rotary in my RX7 for as long as possible and although my mind is made up regarding the next move engine wise I was just checking to see if say someone was really unlucky and had perhaps had to re-build more than say twice in five years.

I agree, it would be interesting to know, i think two important things to also record would be;
1) What was the cause? (i.e. Was it actually anything to do with being a rotary? A clogged fuel filter, dodgy plugs, failing Walbro Fuel pump or overboosting doesnt count)
2) Was it standard?

-And I think 50,000-60,000miles is a fairer, more realistic figure for an FD, FC mileage can vary greatly (possibly due to the much more different types of owners that FC\'s attract -sorry for any generalisation!)
Title: Engine re-build frequency.
Post by: SmbFD3S on October 13, 2008, 11:33:08 PM
At 61,000 miles on UK FD and original engine running 1 bar and runs really well (touches wood) :D
 
Am rebuilding it from end of this month however while it is running well and hopefully wont cost as much :)
Title: Engine re-build frequency.
Post by: clarky350 on October 14, 2008, 12:40:05 AM
Hi I owned a 420bhp single turbo ,nailed it every where for three years , loved it to bits .Never failed me once ,sold it so sad will have to have one again some day.
ps my mate blew his slow cossie up three time in one year, and my other mate spent £3500 in one year fixing his y reg 328 .
Good memory bmw mate crying out for jesus to save him on the way to pub while I nailed rex through the gears great times.
cars owned.
nissan 94 gtr
nissan 200 x2
wrx
rex the best by far
Title: Engine re-build frequency.
Post by: Nik da Greek on October 14, 2008, 01:08:43 AM
My 2p\'s worth would be to agree with what was alluded to above, which is that it might be of more use to enquire why engines have gone pop rather than how often. The best built engine in the world will go off bang pretty quick if its run on low-octane bilge from Sainsburys pumps and modified with filters, de-cat and no re-mapping, but is that a fair assessment of the longevity of the engine?

In actual fact, it was abject cretinism that killed my engine, before I owned the car. The guy I bought it from had run it on standard unleaded (not even Super, let alone Optimax!) and it had a decat exhaust and standard ECU. It used to boost spike like a b@st@rd, and he blew up an apex seal whilst showing off to his mate with his heavy right boot. At that point, the car had done about 80,000 miles on its original engine, and probably didn\'t deserve to meet such a stupid owner!

I\'m sure it would\'ve needed rebuilding by now anyway, but who knows how much longer it\'d have lasted if it hadn\'t been murdered by Moron Boy? For what it\'s worth, the rebuilt engine has outlived the car (which I crashed to death last year) and is still going strong in my current FD something like 30 000 miles later. I don\'t think something as highly strung as a rotary turbo engine has a bad reliability record, tbh, when you appreciate the level of tune they\'re in. Maybe that\'s because I cut my teeth on two-stroke bikes like 250LCs where you needed the reflexes of a striking cobra to get the clutch in at the first sign of "nipping up". One YPVS 350 I had was like riding a hand grenade with the pin out, you knew it was gonna blow, it was just a question of when!
Title: Engine re-build frequency.
Post by: BenLewisMav on October 14, 2008, 02:13:44 AM
Quote from: BenLewisMav;544613I agree, it would be interesting to know, i think two important things to also record would be;
1) What was the cause? (i.e. Was it actually anything to do with being a rotary? A clogged fuel filter, dodgy plugs, failing Walbro Fuel pump or overboosting doesnt count)
2) Was it standard?

3) Was it an original engine?
4) If not, who did the rebuild? (potentially hot water there, but the I\'m sure a reputable engine builder will stand by their work, and any alleviating circumstance would already be explained in question 1.)
Title: Engine re-build frequency.
Post by: BenLewisMav on October 14, 2008, 02:31:04 AM
5) State of porting

.....
Tempted to try start a new thread as a sticky, I think it will become clear what each model\'s weakness are, and hopefully put some myths to rest (aswell as honor the dead!).
Apart from the Model Engine (i.e. 13B-REW, 13BT, etc), State of tune (i.e. STAGE 2 -see below), and the mileage, is there anything else?

State(s) of tune:
|  Stock  |
|  Stage 1: Air Filter, Cat-Back Exhaust  |  
|  Stage 2: De-Cat, Boost Increase, ECU, Intercooler  |  
|  Stage 3: Small-Med Single Turbo Kit (<450hp) |
|  Stage 4: Large Single Turbo (>450hp)  |
Title: Engine re-build frequency.
Post by: Rzla on October 14, 2008, 09:18:33 AM
Quote from: BenLewisMav;544611Yeah that\'s precisely what I was saying (I\'m not sure if you misread it? We kinda said the same thing!)..

I gathered that was what you meant.
I was just adding to it to back up your point and emphasise it lol.
 
Very true with what everyone is saying with regards to what caused the failure.
Using lower octane fuel when your car is mapped for higher RON fuel is your own fault, overboosting is not a fault of the engine ( if a piston engine overboosted it would cause it problems too).
They are just two very small examples. A pipe coming off and blowing the engine is not the cause of engine etc.
Title: Engine re-build frequency.
Post by: FDAsh on October 14, 2008, 03:15:54 PM
As said previously it depends on the treatment of the car. Mine has just gone in to WGT for a rebuild, suspected side seal failure or chipped apex. Told Pip about the rear main bearing I had to replace when I had the car in Germany:

(http://www.corsasport.co.uk/carimages/7661/Image108.jpg)

Apparently that\'s a classic sign of running an engine with no oil in it, so it seems I\'m paying for a previous owner\'s neglect. Still, she got me all the way back from Ingolstadt with the seal problem, so the engines aren\'t as fragile as people make out. I think £3k is a reasonable price for rebuilding an 8-9k revving engine personally. It\'s something I accepted and planned for from day one of ownership, so now the time is here I\'m ready for it. Hopefully year two of ownership will be less problematic.
Title: Engine re-build frequency.
Post by: REVIT93RX7 on October 14, 2008, 05:19:30 PM
Mine had 84,373 miles before the coolant seal failed.  In the process of doing a new motor.  All new fresh parts.  We shall see how she goes.
Title: Engine re-build frequency.
Post by: Hi RX7 on October 14, 2008, 06:24:38 PM
Am I right in thinking then that everyone (if there are any) with a standard engine has got at least 50K miles without a re-build?
Title: Engine re-build frequency.
Post by: FDAsh on October 14, 2008, 06:51:38 PM
I\'d imagine the vast majority have, provided they are properly maintained.
Title: Engine re-build frequency.
Post by: adib on October 14, 2008, 07:23:01 PM
ive had mine 4 years, and its still ok and i drive it every day to work :driving
Title: Engine re-build frequency.
Post by: Hi RX7 on October 14, 2008, 07:24:14 PM
Is it stock spec?
Title: Engine re-build frequency.
Post by: adib on October 15, 2008, 09:54:47 PM
no but still running twin turbos
Title: Engine re-build frequency.
Post by: Hi RX7 on October 15, 2008, 10:20:33 PM
Thats a long time although I\'m no expert, now that my engine has been rebuilt and tuned at Re-Worx I have to say it\'s running really nicely and my confidence in the Rotary engine has been restored if I could get 4 years without a re-build which by the standard of the work done to date could be then I will be well pleased.
Title: Engine re-build frequency.
Post by: karl_tate on October 15, 2008, 11:21:56 PM
mine had done an indicated 50k on what i now think is a untouched engine, which had a single turbo running high boost when it was imported so i have no idea how long it had been on there. the turbo will of also contributed to the failure on stock ports.
Title: Engine re-build frequency.
Post by: adib on October 16, 2008, 08:02:35 PM
keep waiting for it to go pop, but it still keeps going.
was going to pull engine out this year and replace water seals but i mite just leave it and see how long it lasts