hey guys
im looking at buying my self an rx7.iv had a 200sx s14a for a year or so now and want something different. i have been to look at a few but 2 b honest dont realy know what im looking for and i dont want to buy one and it die straight after i get it. i was just wondering if you could give me some pointers on what to look for wen buying one thanx shaun:3Confused
Will depend on budget, and what you are expecting from car, stock or modified.
I have a X members car sat here at my house, he sadly pasted away and has a very clear highly moded car his family want to sell.
I have it to show and sell, but all negotiations are to be done with the family, as I want nothing in it for me, this is just a favor to an old departed friend.
wellim looking for around the 3500 to 4000 mark i just want to kno wat things i need to look out 4 wen buying one and problems that i can check thanx sean
As with any car, try to get one with as much documented history as you can. Oil should have been changed with mineral or semi synthetic every 3 to 4000 miles
Avoid a high milage one (over 100,000 miles) as it\'ll prob need a rebuild soon. No cambelt to worry about though! Lol! Also avoid adverts that say "Vicar never took her above 4000RPM" etc etc words to that avail because apparentley never reving them the full streach as it were is bad for them! :3Confused Something about oil.
Obviousley Check the oil level! But more so with these engines than any other as they consume oil as part of their design.
Also check coolant level! Overheating can be just as bad for these engines as no oil in em!
Check there is no damage to the turbo casing or its heatsheild. E.g cracks
Check the wipers work on all settings if it\'s an FC! (FC boys know what im on about! Lol!)
I think the ECU gives out error codes but i couldnt tell you anything about that. Someone else will fill you in if you ask or alternativley try searching on it.
Oh and make sure to do a test drive and rev right through 3000 4000 500 6000 rpm because somewhere in about there you can get a flat spot. It should be totaly smooth and linear! (after the boost kicks in obviousley!) A lot of the time its an electrical ground problem but there are other causes and its a pain in the arse to nail it down to one or the others. And besides there\'s plenty of RX-7s without that problem.
Steer clear of highley modified ones unless your sure they have been set up right!
Think that covers the major bases.
Good luck and happy hunting!
Check it starts easily from Hot and Cold (difficulty starting from Hot is a sign that the engine is loosing compression. Can\'t remember from cold-start problems are...)
Check for any smoke etc from the exhaust (a little bit on startup is OK, but should go after a second or two)
Check it\'s got a Cat 1 alarm (and check the cert if you can! mine had a \'cat 1\' alarm, which turned out to be 15 yrs old :/)
If its a fresh import (or nearly fresh import) check whether it\'s on Enlish or Jap tyres - if its Jap, you\'ll want to budget to get them swapped asap!
Also, have a dig through the forums, especially the \'General Queries / Hints and Tips on buyin a Rotary\' forum :)
Even in the current market just about anything under 4k has a fair chance of needing work in the near future imo.
With a good reputable full rebuild costing around the 5k mark then anything under that is taking a chance unless you have an expert with you.
Although you could get a 3k bargain and it could give you 30k of trouble free miles, Unlikely but peolpe are letting them go at crazy prices recently
I wrote this on a different forum some time ago, should be of some help:
Buying your first rotary can be a bit of a scary business. When I bought my S6 RX-7 I bought from Jimmys Rotary Specialist with a 1 year warranty and a new rebuilt engine. Thankfully I didn’t need to use the warranty but it’s always nice to have for a safety net.
There are a few things to watch out for when looking round and test driving FD3S RX-7’s. This is just a few specific I can think of, obviously there are all the normal ones to look for like evidence of a crash etc.:
Testing the turbo’s. If the car is a standard sequential-twin-turbo you should see the first turbo spooling up around 3000 to 3500rpm showing 10psi on the gauge then at about 4000rpm the second turbo will start to spool and a drop in pressure will be seen to about 8psi then at about 4500rpm the gauge should read 10psi all the way to the red line. If you do this test in 3rd gear be careful as by the time you hit the red-line you’re going to be doing the best part of 160km/h…..!
It’s very easy to fit a turbo pressure gauge to an FD3S RX-7 as on the plenum there is a spare nipple with a black plastic cover over it, simply connect to this.
If the car has been modified to have a non-sequential-twin-turbo set up the turbo’s will spool up together (like a single turbo) producing a different boost pattern to the one above.
The turbo\'s are controlled via many vacuum hoses which have become affectionately knows as ‘The Rats Nest’ which when you look at it will become very obvious. The temperature under the bonnet get’s quite high and as a consequence the vacuum hoses over time will get very brittle snap or crack causing varying different boost problems. Have a good look at these pipes the standard pipes are black, many people (including myself) when replacing will used colour silicone pipes.
Have a look at the cooling fluid, there are 3 places to check, and this must be done before test drive. Firstly have a look under the radiator cap located central of the engine bay, hopefully the water should be a couple of inches below the cap. Next look in the AST (Air Separation Tank, it says not to open, but as long as the car is cold not a problem) this is located at the from of the engine bay just off centre to the right, this should be full. Thirdly in the far left of the engine bay is a plastic coolant container, this is an overflow chamber and will fill up and empty of the engine warms and cools. A useful test to perform is to start the engine with the centre radiator cap removed, this is commonly called a Champaign bubble test. Basically your looking for bubble coming up through the water, a few is okay, but if the water look like champaign bubbling and overflows probably a sign of a water seal on the way out. Time for a rebuild….!
It’s best when arranging to go for a test drive to ask if the car can be cold for when you arrive. Starting an RX-7 from cold should be easy…….Start the car out of gear without pressing the accelerator, if you can. This will cause the car to start and hopefully tick over (until warmed up) at about 2000rpm, Mazda did this to facilitate warning the car up faster, some people like this, others not, personal preference. The car should after a few minutes reduce the tick over speed to around 800rpm. After the test drive let the car cool down for a few minutes with the engine running, this allows oil to be continually pumped to the turbo’s stopping overheating of the turbo’s. After about 30 mins or so with the engine off try restarting the engine, as the car will still be warm it should start and idle almost immediately at about 800rpm.
When first starting the car don’t be surprised to see smoke from the tail pipe, this tends to be from the residual oil in the rotor chambers. RX-7 have oil metering pumps which inject oil into the rotor housing to keep the tips from excessive wear. Some oil will remain in the rotor housing and upon start-up will get burn producing the smoke. This smoke should go away.
During the test drive try accelerating smoothly through the rev range (not foot to floor) hopefully the car will accelerate smoothly as well. However you may notice a slight hesitation at around 3000rpm, to date there is no definite answer to this problem. Sometimes fitting an earthing kit can help, fitting a different CPU like an Apexi Power FC can help, but no definite answer. When accelerating the car should not smoke.
If you decide that the car looks and drives good it might be worth paying to have a compression test done. Having a compression test done on a rotary car is different from a piston engine and requires a different bit of kit. The compression test will test each rotor in turn and provide 3 reading for each rotor. You looking for a value above 7kg/cm2, for each rotor chamber. If the values for a given rotor vary by more than 1kg/cm2 it may need a rebuild.
Once you have purchased you car you need to be prepared to change the oil every 5000km and always use mineral oil. Using semi-synthetic or fully synthetic will cause deposit build-up on the inside of the rotor housing due to the rotary engine injecting oil as talk about earlier.
If you need any further help don’t hesitate to ask.
Cheers,
James.
thanx for your help guys i have found a rx and has been compression tested as follows
1st cylinder
6.8 94psi
6.8 94psi
6.3 90psi
2nd cylinder
7.0 100psi
6.9 99psi
6.8 97psi
its claimed to have had a engine rebuild 20k ago. does this sound like a good engine or is it going to last my 5 mins thanx shaun
rebuilt by RXmotors just to add company based in dorset
Your looking for a compression value per chamber of around 7kg/cm2
As stated in post above
7kg/cm2 = 99.6 psi/6.86 bar
All the chambers on the engine above are pretty much bang on that
If the values were different by more than 1kg/cm2 then it may need a rebuild \'as stated above\'
A value drop of 1kg/cm2 would be:
6kg/cm2 = 85.3 psi/5.88 bar
None of the chambers on that engine are anywhere near this!
Hope this helps!
To add
The largest difference is between 94 psi and 90 psi
94 psi = 6.61 kg/cm2/6.48 bar
90 psi = 6.33 kg/cm2/6.21 bar
As you can see, this is only a 0.30 kg/cm2 difference
All sounds good
so is this engine in good working order and probaly has had a rebuild as stated thanx shaun
Quote from: Shaunyboi40;553403thanx for your help guys i have found a rx and has been compression tested as follows
1st cylinder
6.8 94psi
6.8 94psi
6.3 90psi
2nd cylinder
7.0 100psi
6.9 99psi
6.8 97psi
its claimed to have had a engine rebuild 20k ago. does this sound like a good engine or is it going to last my 5 mins thanx shaun
Sounds like a heavily modded rex, its got two cylinders :D
on a serious note. Id we worried about the front rotor as there is quite a difference in the compression between the 3 cambers. ( not sure how big a difference is bad)
apart from that its not to bad
A difference of over 1kg/cm2 is when you would need to be cautious!
The chambers are pretty much identical in difference to almost all compression test figures on the FD3S.