Well, u shud look at the FAQ section...i'll explain anyway eventho im not yet a RX7 owner but im sure is a true admirer of the Legendary Great 7...about buying the car u shud look out for the engine..well this is the answer:
1. Check for proper turbo operation. Problems with the secondary turbo are common. On a test drive with a warm engine at full throttle, the second turbo should kick in with the punch of a jet aircraft's afterburner. Though Mazda didn't install a boost gauge, it's easy to hook up a temporary gauge to the intake manifold. The dial should read 10 psi, then drop to 8 psi at 4500 rpm, then quickly recover to 10 psi. Turbo housings are difficult to obtain, which means that pooped-out turbos can't be rebuilt and must be replaced with new turbos — a pricey proposition.
2. Inspect vacuum lines and wiring. Malfunctioning turbos may also be caused by problems with the RX-7's complex array of vacuum lines and solenoid valves. High under-hood temperatures from the turbos often cause the lines to harden and break, and the solenoids to fail. Ditto for engine-bay wiring and electrical connections.
3. Perform a compression check. Rotary engines require special test equipment available at a dealer or rotary specialist. But a check is especially important as these engines often need rebuilding after only 50,000 or 60,000 miles because the aluminum engine housing warps and/or seals fail and allow coolant to enter the rotor chambers.
4. Examine the cooling system. Rotary engines run hotter than piston engines, and the turbos only add to the heat generation. Proper engine cooling is critical, and if the needle on the temperature gauge rises to "Hot" even once, the engine's probably cooked. On a cold engine, the coolant level should be full and the coolant should be green with no signs of oil. White smoke or the sweet smell of coolant from the tailpipe indicates trouble. The electric fans — there are two — frequently come apart, perhaps launching a blade into the radiator. And the cooling system's plastic air separator often splits, dumping out coolant.
5. Read the service history. The records should show oil-change intervals of no longer than 2000 to 3000 miles. Gasoline residue is more likely to contaminate the oil of a rotary engine than a piston engine, and the oil breaks down more quickly because it's used to cool the turbos, so frequent changes are a must. Oil consumption of a quart per 1500 miles is normal. Oil pressure at idle should be at least 20 psi.
6. Check gearbox for smooth shifting. The manual transmission is generally strong, but a damaged 5th-gear synchro is not uncommon on these RX-7s. Note any crunching when going into 5th gear.
7. Listen for suspension clunks. Noises from the aft end of the car may come from one or more of a dozen deteriorated bushings in the rear suspension, while clunks at the front probably come from an upper A-arm bushing. Any can be replaced with upgraded bushings
Quoted by Alchemis
next is the maintenance and the problems:
Basically, maintenance of RE is nothing... very EASY... nothing to be worried off. for a stock car the suggestion is always get a mineral oil only RM50 per 4 litre. and a Mazda oil filter that's around RM 25 to RM 30 per piece....
most important of this lesson... change them every 3000 miles, or 5000 KM THE MOST....
some of the RE folks might say go synthetic, there's a big discussion and argument in the RX7club.com regarding this topic... Logically speaking, our car pumps oil into the engine for lubrication.. it's being burnt.... if the oil burns un-clean... then you'll have alot of dust and deposits. if it's high grade synthetic.. u don't get it burn... i don't know where the oil goes then :)
i know if i use mineral.. it gets evaporated.... so.. i need to top up about 500 ML every half year :) that's not a significant oil lost :) it's normal.
Gear boxes....we're talking about gear box oils, rear axel oils and linkages. if you don't know the history of the gear box oil or the LSD oil, change it once u get the car.... it should last you up to at least 2 years if you're not racing ur car constantly.
how much ? go ask a foreman... gear box oil... usually sell in 1 litre form... you'll need maybe 4 bottles ? and LSD need 2 bottles... and price is depending on what brand u use.
linkages..... as you know, they are wrapped in a rubber piece... greeses are applied inside. once the rubber piece gave up.... time to change the linkages... it'll get worn... you'll be having difficulty getting a right wheel allignment or noises when you drive through rough roads. cross your fingers, this don't happen to you :)
Radiator...... there has been people saying use Water Wetter + de-mineralized water + coolant (25 % only). it does help a little.... but not a significant cash involved.... change them once a year.... it should help your engine to be rust free... and clog free.... this set you off for around RM 50 to RM 80.....
the rest..... brake pads normal question.. finish then change lor.... no need to ask kua :)
i think at the moment that's what i have in my mind for begineers.... i hope some other member could come and post more FAQ for intermediate drivers in term of electronics etc.. what is required in the car... what to do .. what not to do.. what to be careful :)
Quoted by Alchemis
and finally is it a reliable car:
it really depends...some 7's are bulletproof but some 7's breaks down too...it really depends how much pampering and care u give to the car...the more money u spend on cooling parts and engine stuff...the more reliable it is basically...
so there it is...ur 3 questions answered :) cheerz
